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Sample records for classical age-period-cohort approach

  1. Time trends in exposure of cattle to bovine spongiform encephalopathy and cohort effect in France and Italy: value of the classical Age-Period-Cohort approach

    Directory of Open Access Journals (Sweden)

    Ru Giuseppe

    2009-09-01

    Full Text Available Abstract Background The Age-Period-Cohort (APC analysis is routinely used for time trend analysis of cancer incidence or mortality rates, but in veterinary epidemiology, there are still only a few examples of this application. APC models were recently used to model the French epidemic assuming that the time trend for BSE was mainly due to a cohort effect in relation to the control measures that may have modified the BSE exposure of cohorts over time. We used a categorical APC analysis which did not require any functional form for the effect of the variables, and examined second differences to estimate the variation of the BSE trend. We also reanalysed the French epidemic and performed a simultaneous analysis of Italian data using more appropriate birth cohort categories for comparison. Results We used data from the exhaustive surveillance carried out in France and Italy between 2001 and 2007, and comparatively described the trend of the epidemic in both countries. At the end, the shape and irregularities of the trends were discussed in light of the main control measures adopted to control the disease. In Italy a decrease in the epidemic became apparent from 1996, following the application of rendering standards for the processing of specific risk material (SRM. For the French epidemic, the pattern of second differences in the birth cohorts confirmed the beginning of the decrease from 1995, just after the implementation of the meat and bone meal (MBM ban for all ruminants (1994. Conclusion The APC analysis proved to be highly suitable for the study of the trend in BSE epidemics and was helpful in understanding the effects of management and control of the disease. Additionally, such an approach may help in the implementation of changes in BSE regulations.

  2. A Novel Approach for Analysis of the Log-Linear Age-Period-Cohort Model: Application to Lung Cancer Incidence

    Directory of Open Access Journals (Sweden)

    Tengiz Mdzinarishvili

    2009-12-01

    Full Text Available A simple, computationally efficient procedure for analyses of the time period and birth cohort effects on the distribution of the age-specific incidence rates of cancers is proposed. Assuming that cohort effects for neighboring cohorts are almost equal and using the Log-Linear Age-Period-Cohort Model, this procedure allows one to evaluate temporal trends and birth cohort variations of any type of cancer without prior knowledge of the hazard function. This procedure was used to estimate the influence of time period and birth cohort effects on the distribution of the age-specific incidence rates of first primary, microscopically confirmed lung cancer (LC cases from the SEER9 database. It was shown that since 1975, the time period effect coefficients for men increase up to 1980 and then decrease until 2004. For women, these coefficients increase from 1975 up to 1990 and then remain nearly constant. The LC birth cohort effect coefficients for men and women increase from the cohort of 1890–94 until the cohort of 1925–29, then decrease until the cohort of 1950–54 and then remain almost unchanged. Overall, LC incidence rates, adjusted by period and cohort effects, increase up to the age of about 72–75, turn over, and then fall after the age of 75–78. The peak of the adjusted rates in men is around the age of 77–78, while in women, it is around the age of 72–73. Therefore, these results suggest that the age distribution of the incidence rates in men and women fall at old ages.

  3. Bayesian Age-Period-Cohort Modeling and Prediction - BAMP

    Directory of Open Access Journals (Sweden)

    Volker J. Schmid

    2007-10-01

    Full Text Available The software package BAMP provides a method of analyzing incidence or mortality data on the Lexis diagram, using a Bayesian version of an age-period-cohort model. A hierarchical model is assumed with a binomial model in the first-stage. As smoothing priors for the age, period and cohort parameters random walks of first and second order, with and without an additional unstructured component are available. Unstructured heterogeneity can also be included in the model. In order to evaluate the model fit, posterior deviance, DIC and predictive deviances are computed. By projecting the random walk prior into the future, future death rates can be predicted.

  4. Age-period-cohort modelling of breast cancer incidence in the Nordic countries

    DEFF Research Database (Denmark)

    Rostgaard, K; Vaeth, M; Holst, H;

    2001-01-01

    The Nordic countries have experienced a steady increase in breast cancer incidence throughout the past 35 years. We analysed the incidence in Denmark, Finland, Norway and Sweden during the period 1958 to 1992 using age-period-cohort models and taking the systematic mammography screening into acco...... been exposed to an increasing load of cohort borne breast cancer risk factors not experienced to the same extent by Norwegian women, whereas they were seemingly subjected to the same period effects.......The Nordic countries have experienced a steady increase in breast cancer incidence throughout the past 35 years. We analysed the incidence in Denmark, Finland, Norway and Sweden during the period 1958 to 1992 using age-period-cohort models and taking the systematic mammography screening into...... in breast cancer incidence seen in the Nordic countries. The widespread practice of neglecting the period effects in age-period-cohort analysis of time trends in breast cancer incidence therefore probably needs reconsideration. A key finding was that Danish women born in the 20th century seem to have...

  5. Inference and forecasting in the age-period-cohort model with unknown exposure with an application to mesothelioma mortality

    OpenAIRE

    Martinez-Miranda, M. D.; Nielsen, B; J.P. Nielsen

    2014-01-01

    It is of considerable interest to forecast future mesothelioma mortality. No measures for exposure are available so it is not straight forward to apply a dose-response model. It is proposed to model the counts of deaths directly using a Poisson regression with an age-period-cohort structure, but without offset. Traditionally the age-period-cohort is viewed to suffer from an identification problem. It is shown how to re-parameterize the model in terms of freely varying parameters, so as to avo...

  6. Temporal Trends of Suicide Mortality in Mainland China: Results from the Age-Period-Cohort Framework.

    Science.gov (United States)

    Wang, Zhenkun; Wang, Jinyao; Bao, Junzhe; Gao, Xudong; Yu, Chuanhua; Xiang, Huiyun

    2016-01-01

    The aim of this study is to explore the long-term trends of suicide mortality in China. We implemented the age-period-cohort (APC) framework, using data from the Global Burden of Disease Study 2013. Our results showed that the net drift of suicide mortality was -4.727% (95% CI: -4.821% to -4.634%) per year for men and -6.633% (95% CI: -6.751% to -6.515%) per year for women, and the local drift values were below 0 in all age groups (p risk increased rapidly to peak at the life stage of 20-24 years old and 15-24 years old for men and women, respectively, and then showed a decelerated decline, followed by a rise thereafter after 54 years old for men and a slight one after 69 years old for women. The estimated period and cohort RRs were found to show similar monotonic downward patterns (significantly with p pesticides and rodenticides might be the special reasons behind these trends we observed in this study. PMID:27527195

  7. Clarifying hierarchical age-period-cohort models: A rejoinder to Bell and Jones.

    Science.gov (United States)

    Reither, Eric N; Land, Kenneth C; Jeon, Sun Y; Powers, Daniel A; Masters, Ryan K; Zheng, Hui; Hardy, Melissa A; Keyes, Katherine M; Fu, Qiang; Hanson, Heidi A; Smith, Ken R; Utz, Rebecca L; Yang, Y Claire

    2015-11-01

    Previously, Reither et al. (2015) demonstrated that hierarchical age-period-cohort (HAPC) models perform well when basic assumptions are satisfied. To contest this finding, Bell and Jones (2015) invent a data generating process (DGP) that borrows age, period and cohort effects from different equations in Reither et al. (2015). When HAPC models applied to data simulated from this DGP fail to recover the patterning of APC effects, B&J reiterate their view that these models provide "misleading evidence dressed up as science." Despite such strong words, B&J show no curiosity about their own simulated data--and therefore once again misapply HAPC models to data that violate important assumptions. In this response, we illustrate how a careful analyst could have used simple descriptive plots and model selection statistics to verify that (a) period effects are not present in these data, and (b) age and cohort effects are conflated. By accounting for the characteristics of B&J's artificial data structure, we successfully recover the "true" DGP through an appropriately specified model. We conclude that B&Js main contribution to science is to remind analysts that APC models will fail in the presence of exact algebraic effects (i.e., effects with no random/stochastic components), and when collinear temporal dimensions are included without taking special care in the modeling process. The expanded list of coauthors on this commentary represents an emerging consensus among APC scholars that B&J's essential strategy--testing HAPC models with data simulated from contrived DGPs that violate important assumptions--is not a productive way to advance the discussion about innovative APC methods in epidemiology and the social sciences. PMID:26277370

  8. Increasing thyroid cancer incidence in Canada, 1970–1996: time trends and age-period-cohort effects

    OpenAIRE

    Liu, S; Semenciw, R; Ugnat, A-M; Mao, Y.(State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing, China)

    2001-01-01

    We examined time trends in thyroid cancer incidence in Canada by age, time period and birth cohort between 1970 and 1996. Age-specific incidence rates by time period and birth cohort were calculated and age-period-cohort modelling used to estimate effects underlying the observed trends. Overall age-adjusted incidence rates of thyroid cancer doubled, from 3.3 and 1.1 per 100 000 in 1970–72 to 6.8 and 2.2 per 100 000 in 1994–96, among females and males respectively. Almost all the increase betw...

  9. Trends in environmental lead exposure and troubled youth, 1960-1995: an age-period-cohort-characteristic analysis.

    Science.gov (United States)

    McCall, Patricia L; Land, Kenneth C

    2004-06-01

    Beginning in the mid-1980s and extending into the early 1990s, the United States experienced a wave of increased youth violence and teenage pregnancy. Nevin (2000) proffers a cohort-based explanation that these trends can be attributed to corresponding trends in gasoline lead exposure during the youths' early years. He contends that the increased consumption of adversely impacted their intelligence levels (IQs). This decreased their intellectual ability, resulted in poor decisions made during their teen and young adult years, and in turn, led to disproportionally high level of criminal involvement and unwed pregnancies among this cohort. The present study evaluates Nevin's causal model by testing the connection between trends in lead exposure and youthful problem behavior with age-period-cohort-characteristic (APCC) models. Our research finds no support for this cohort explanation. PMID:15216841

  10. Time Trends of Italian Former Smokers 1980–2009 and 2010–2030 Projections Using a Bayesian Age Period Cohort Model

    Directory of Open Access Journals (Sweden)

    Giulia Carreras

    2013-12-01

    Full Text Available This study aimed to describe past time trends of the prevalence of former smokers in Italy and to estimate prevalence projections using a Bayesian approach. An age-period-cohort (APC analysis has been carried out in order to investigate the effect of the age, period and birth cohort on the prevalence of former smokers during 1980–2009. A Bayesian APC model with an autoregressive structure for the age, period and cohort parameters has been used to estimate future trends. Results showed that awareness of harm from smoking occurred at younger ages with each advancing cohort, and that women were more likely to attempt to stop smoking during pregnancies and breastfeeding, whereas men attempted to quit only when smoking-related diseases became evident. Projections of future trend recorded a further increase in the number of former smokers in future decades, showing an estimate of the “end of smoking” around years 2060 and 2055 in men and women, respectively. The application of the APC analysis to study the prevalence of former smokers turned out to be a useful method for the evaluation of past smoking trends, reflecting the effects of tobacco control policies on time and generations, and to make projections of future trend.

  11. Evidence for cervical cancer mortality with screening program in Taiwan, 1981–2010: age-period-cohort model

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    Su Shih-Yung

    2013-01-01

    Full Text Available Abstract Background Cervical cancer is the most common cancer experienced by women worldwide; however, screening techniques are very effective for reducing the risk of death. The national cervical cancer screening program was implemented in Taiwan in 1995. The objective of this study was to examine and provide evidence of the cervical cancer mortality trends for the periods before and after the screening program was implemented. Methods Data from 1981 to 2010 of the causes of death registered were obtained from the Department of Health, Taiwan. Age-standardized mortality rates, age-specific rates, and age-period-cohort models that employed the sequential method were used to assess temporal changes that occurred between 1981 and 2010, with 1995 used as the separating year. Results The results showed that for both time periods of 1981 to 1995 and 1996 to 2010, age and period had significant effects, whereas the birth cohort effects were insignificant. For patients between 80 and 84 years of age, the mortality rate for 1981 to 1995 and 1996 to 2010 was 48.34 and 68.08. The cervical cancer mortality rate for 1996 to 2010 was 1.0 for patients between 75 and 79 years of age and 1.4 for patients between 80 and 84 years of age compared to that for 1981 to 1995. Regarding the period effect, the mortality trend decreased 2-fold from 1996 to 2010. Conclusions The results of this study indicate a decline in cervical cancer mortality trends after the screening program involving Papanicolaou tests was implemented in 1995. However, the positive effects of the screening program were not observed in elderly women because of treatment delays during the initial implementation of the screening program.

  12. Secular Trends of Breast Cancer in China, South Korea, Japan and the United States: Application of the Age-Period-Cohort Analysis

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    Zhenkun Wang

    2015-12-01

    Full Text Available To describe the temporal trends of breast cancer mortality in East Asia and to better understand the causes of these trends, we analyzed the independent effects of chronological age, time period and birth cohort on breast cancer mortality trends using age-period-cohort (APC analysis. We chose three main countries in East Asia, namely China, South Korea, and Japan, which have reported death status to the WHO Mortality Database, and used the United States as a comparison population. Our study shows that in general, breast cancer mortality rates in females increased in all three East Asian countries throughout the study period. By APC analysis, we confirmed that there is, in fact, a difference in age-specific mortality rate patterns between the Eastern and the Western countries, which is presumably caused by the two-disease model. While the cause of the decrease from approximately the 1950s generation is still in question, we believe that increasing general awareness and improvements in the health-care system have made a significant contribution to it. Although the age and cohort effects are relatively strong, the period effect may be a more critical factor in the mortality trend, mainly reflecting the increase in exposures to carcinogens and behavioral risk factors.

  13. Incidence trend of nasopharyngeal carcinoma from 1987 to 2011 in Sihui County, Guangdong Province, South China:an age-period-cohort analysis

    Institute of Scientific and Technical Information of China (English)

    Li-Fang Zhang; Yan-Hua Li; Shang-Hang Xie; Wei Ling; Sui-Hong Chen; Qing Liu; Qi-Hong Huang; Su-Mei Cao

    2015-01-01

    Introduction:In the past several decades, declining incidences of nasopharyngeal carcinoma (NPC) have been observed in Chinese populations in Hong Kong, Taiwan, Los Angeles, and Singapore. A previous study indicated that the incidence of NPC in Sihui County, South China remained stable until 2002, but whether age, diagnosis period, and birth cohort affect the incidence of NPC remains unknown. Methods:Age-standardized rates (ASRs) of NPC incidence based on the world standard population were examined in both males and females in Sihui County from 1987 to 2011. Joinpoint regression analysis was conducted to quantify the changes in incidence trends. A Poisson regression age-period-cohort model was used to assess the effects of age, diagnosis period, and birth cohort on the risk of NPC. Results:The ASRs of NPC incidence during the study period were 30.29/100,000 for males and 13.09/100,000 for females. The incidence of NPC remained stable at a non-significant average annual percent change of 0.2%for males and−1.6%for females throughout the entire period. A significantly increased estimated annual percent change of 6.8%(95%confidence interval, 0.1%–14.0%) was observed from 2003 to 2009 for males. The relative risk of NPC increased with advancing age up to 50–59 and decreased at ages>60 years. The period effect curves on NPC were nearly flat for males and females. The birth cohort effect curve for males showed an increase from the 1922 cohort to the 1957 cohort and a decrease thereafter. In females, there was an undulating increase in the relative risk from the 1922 cohort to the 1972 cohort. Conclusions:The incidence trends for NPC remained generally stable in Sihui from 1987 to 2011, with an increase from 2003 to 2009. The relative risks of NPC increased in younger females.

  14. CLASSIC APPROACH TO BUSINESS COACHING

    OpenAIRE

    Żukowska, Joanna

    2011-01-01

    The purpose of this paper is to present business coaching in a classical way. An overview of coaching definitions will be provided. Attention will be drawn to coaching components and varieties. Moreover, a brief description of coach competences and tools supporting their work will be offered. Joanna Żukowska

  15. Three Approaches to Classical Thermal Field Theory

    OpenAIRE

    Gozzi, E.; Penco, R.

    2010-01-01

    In this paper we study three different functional approaches to classical thermal field theory, which turn out to be the classical counterparts of three well-known different formulations of quantum thermal field theory: the Closed-Time Path (CTP) formalism, the Thermofield Dynamics (TFD) and the Matsubara approach.

  16. Three approaches to classical thermal field theory

    Science.gov (United States)

    Gozzi, E.; Penco, R.

    2011-04-01

    In this paper we study three different functional approaches to classical thermal field theory, which turn out to be the classical counterparts of three well-known different formulations of quantum thermal field theory: the closed-time path (CTP) formalism, the thermofield dynamics (TFD) and the Matsubara approach.

  17. A modern approach to classical mechanics

    CERN Document Server

    Iro, Harald

    2002-01-01

    The approach to classical mechanics adopted in this book includes and stresses recent developments in nonlinear dynamical systems. The concepts necessary to formulate and understand chaotic behavior are presented. Besides the conventional topics (such as oscillators, the Kepler problem, spinning tops and the two centers problem) studied in the frame of Newtonian, Lagrangian, and Hamiltonian mechanics, nonintegrable systems (the Hénon-Heiles system, motion in a Coulomb force field together with a homogeneous magnetic field, the restricted three-body problem) are also discussed. The question of the integrability (of planetary motion, for example) leads finally to the KAM-theorem. This book is the result of lectures on 'Classical Mechanics' as the first part of a basic course in Theoretical Physics. These lectures were given by the author to undergraduate students in their second year at the Johannes Kepler University Linz, Austria. The book is also addressed to lecturers in this field and to physicists who wa...

  18. Análisis edad-periodo-cohorte de la mortalidad por accidentes de tráfico en España Age-period-cohort analysis of traffic accident mortality in Spain

    Directory of Open Access Journals (Sweden)

    Carmen Saiz-Sánchez

    1999-05-01

    Full Text Available OBJETIVO. Estudiar la evolución de la mortalidad por accidentes de tráfico en España y su posible aplicación a un modelo edad-periodo-cohorte, así como el efecto que pueden tener algunas medidas de seguridad vial seleccionadas. MATERIAL Y MÉTODOS. Se obtuvieron las tasas de mortalidad por accidentes de tráfico y las tasas en intervalos quinquenales de edad para cada sexo, lo que permite su estudio como tasas específicas de edad por cohortes de nacimiento. Para determinar la asociación entre las medidas de seguridad vial seleccionadas y la mortalidad se han construido modelos de regresión de Poisson. RESULTADOS. Se observaron dos ondas evolutivas en la mortalidad por accidentes de tráfico. Respecto a la edad, no podemos hablar de un efecto claro; tampoco se encontró un efecto cohorte ni para varones ni para mujeres. En relación con las medidas de seguridad vial, se discutió la consistencia que guardaban los modelos seleccionados con los resultados gráficos, y se obtuvo que el uso obligatorio del casco y de las luces de cruce en motocicletas se ha asociado significativamente a la reducción de la mortalidad (RR 0.73, pOBJECTIVE. To study the evolution of traffic accidents mortality in Spain and its possible application to an age-period-cohort analysis, as well as the effect of selected road safety measures. MATERIAL AND METHODS. Road accidents rates of mortality were obtained, and five-year interval age rates for each sex, which allows the study of specific rates of age by birth cohorts. To determine the association between the selected road safety measures and mortality, Poisson regression models were adjusted. RESULTS. Two waves emerge in the evolution of traffic accidents. There was no clear effect with respect to age, nor was there a cohort effect for men or women. As to the road safety measures, we discuss the consistency between the selected models and graphic results. The compulsory use of helmet and of crossing lights is

  19. Classical stochastic approach to cosmology revisited

    Indian Academy of Sciences (India)

    Moncy V John; C Sivakumar; K Babu Joseph

    2003-01-01

    The classical stochastic model of cosmology recently developed by us is reconsidered. In that approach the parameter defined by the equation of state = wρ was taken to be fluctuating with mean zero and we compared the theoretical probability distribution function (PDF) for the Hubble parameter with observational data corresponding to a universe with matter and vacuum energy. Even though qualitative agreement between the two was obtained, an attempt is herein made to introduce a more realistic assumption for the mean ofwand use it for the calculations. In the present theory the mean values of both and are taken to be nonzero. The theoretical and observational PDFs are compared for different epochs and values of the Hubble parameter. The corresponding values of the diffusion constant obtained are approximately constant. We use the scatter in the observed redshift-magnitude data of Type Ia supernova to place limits on the stochastic variation in expansion rate and consequently, on the stochastic variation of the equation of state.

  20. Functional Approach to Classical Yang-Mills Theories

    CERN Document Server

    Carta, P

    2002-01-01

    Sometime ago it was shown that the operatorial approach to classical mechanics, pioneered in the 30's by Koopman and von Neumann, can have a functional version. In this talk we will extend this functional approach to the case of classical field theories and in particular to the Yang-Mills ones. We shall show that the issues of gauge-fixing and Faddeev-Popov determinant arise also in this classical formalism.

  1. Simple classical approach to spin resonance phenomena

    DEFF Research Database (Denmark)

    Gordon, R A

    1977-01-01

    A simple classical method of describing spin resonance in terms of the average power absorbed by a spin system is discussed. The method has several advantages over more conventional treatments, and a number of important spin resonance phenomena, not normally considered at the introductory level...

  2. Prostate cancer mortality trends in Argentina 1986-2006: an age-period-cohort and joinpoint analysis Tendencias en la mortalidad por cáncer de próstata en Argentina 1986-2006: análisis joinpoint y de edad-período-cohorte

    OpenAIRE

    Camila Niclis; Sonia A. Pou; Rubén H. Bengió; Alberto R. Osella; María del Pilar Díaz

    2011-01-01

    The aim of this study was to give an overview of the magnitude, variation by age and time trends in the rates of prostate cancer mortality in Córdoba province and in Argentina as a whole from 1986 to 2006. Mortality data were provided by the Córdoba Ministry of Health and the World Health Organization cancer mortality database. Prostate cancer mortality time trends were analyzed using joinpoint analysis and age-period-cohort models. In Argentina prostate cancer age-standardized mortality rate...

  3. A "Classic Papers" Approach to Teaching Undergraduate Organometallic Chemistry

    Science.gov (United States)

    Duncan, Andrew P.; Johnson, Adam R.

    2007-01-01

    We have structured an upper-level undergraduate course in organometallic chemistry on a selection of "classic" publications in the field. This approach offers students a richly contextual introduction to many of the fundamental tenets of the discipline. After a brief introduction to the field led by the faculty, the students themselves are…

  4. Scattering approach to classical quasi-1D transport

    OpenAIRE

    Kogan, Eugene

    1996-01-01

    General dynamical transport of classical particles in disordered quasi-1D samples is viewed in the framework of scattering approach. Simple equation for the transfer-matrix is obtained within this unified picture. In the case of diffusive transport the solution of this equation exactly coincides with the solution of diffusion equation.

  5. Classical approach to H2+-H(1s) collisions

    International Nuclear Information System (INIS)

    Collisions between H2+ ion projectiles with H targets have been investigated in the 2.5-1000 keV energy range by means of classical-trajectory Monte Carlo calculations. It has been possible to simulate classically a dynamical H2+ molecule and, therefore, the approach includes all the Coulomb interactions between the five classical particles. Particular attention is paid to the description of the H2+ ion projectile, initially in its first vibration (v=0) ground state, and to the identification of the various reaction products after collision. Total cross sections for all the possible reaction channels are calculated, and are found in fair agreement with recent experimental data in the 20-100 keV energy range. Final n-state distributions for the hydrogen fragments are also determined

  6. Classical and Modern Approaches Used for Viral Hepatitis Diagnosis

    OpenAIRE

    Heiat, Mohammad; Ranjbar, Reza; Alavian, Seyed Moayed

    2014-01-01

    Context: Viral hepatitis diagnosis is an important issue in the treatment procedure of this infection. Late diagnosis and delayed treatment of viral hepatitis infections can lead to irreversible liver damages and occurrence of liver cirrhosis and hepatocellular carcinoma. A variety of laboratory methods including old and new technologies are being applied to detect hepatitis viruses. Here we have tried to review, categorize, compare and illustrate the classical and modern approaches used for ...

  7. Methodology Approaches Regarding Classic versus Mobile Enterprise Application Development

    OpenAIRE

    Vasile-Daniel PAVALOAIA

    2013-01-01

    In the nowadays enterprise computerized context, there is a trend that shifts the business ap-plications to the new mobile environments. In the light of this information, it is highly important to be knowledgeable about the software development methodologies available in order to make the right choice when it comes to developing a mobile application. The current research aims to presenting the methodological approaches regarding the development cycle of classic enterprise software versus mobi...

  8. Hybrid quantum-classical approach to correlated materials

    Science.gov (United States)

    Bauer, Bela; Wecker, Dave; Millis, Andrew J.; Hastings, Matthew B.; Troyer, Matthias

    Recent improvements in control of quantum systems make it seem feasible to finally build a programmable general-purpose quantum computer within a decade. While it has been shown that such a quantum computer can in principle solve certain small electronic structure problems and idealized model Hamiltonians, the highly relevant problem of directly solving a complex correlated material appears to require a prohibitive amount of resources. Here, we show that by using a hybrid quantum-classical algorithm that incorporates the power of a small quantum computer into a framework of classical embedding algorithms, the electronic structure of complex correlated materials can be efficiently tackled using a quantum computer. In our approach, the quantum computer solves a small effective quantum impurity problem that is self-consistently determined via a feedback loop between the quantum and classical computation. Use of a quantum computer enables much larger and more accurate simulations than with any known classical algorithm, and will allow many open questions in quantum materials to be resolved once a small quantum computer with around one hundred logical qubits becomes available.

  9. Geometric aspects in extended approach of equilibrium classical fluctuation theory

    Science.gov (United States)

    Velazquez, L.

    2011-11-01

    Previously, an extended approach of equilibrium classical fluctuation theory was developed compatible with the existence of anomalous response functions, e.g. states with negative heat capacities. Now, the geometric aspects associated with this new framework are analyzed. The analysis starts from the so-called reparametrization invariance: a special symmetry of distribution functions dp (I|θ) employed in classical equilibrium statistical mechanics that allows us to express the thermo-statistical relations in the same mathematical appearance in different coordinate representations. The existence of reparametrization invariance can be related to three different geometric frameworks: (1) a non-Riemannian formulation for classical fluctuation theory based on the concept of reparametrization dualities; (2) a Riemannian formulation defined on the manifold {P} of control parameters θ, where the main theorems of inference theory appear as dual counterparts of general fluctuation theorems, and Boltzmann-Gibbs distributions ωBG(I|θ) = exp(-θiIi)/Z(θ) admit a geometric generalization; and finally, (3) a Riemannian formulation defined on the manifold {M}_{\\theta } of macroscopic observables I, which appears as a counterpart approach of inference geometry.

  10. Path integral approach to electron scattering in classical electromagnetic potential

    Science.gov (United States)

    Chuang, Xu; Feng, Feng; Ying-Jun, Li

    2016-05-01

    As is known to all, the electron scattering in classical electromagnetic potential is one of the most widespread applications of quantum theory. Nevertheless, many discussions about electron scattering are based upon single-particle Schrodinger equation or Dirac equation in quantum mechanics rather than the method of quantum field theory. In this paper, by using the path integral approach of quantum field theory, we perturbatively evaluate the scattering amplitude up to the second order for the electron scattering by the classical electromagnetic potential. The results we derive are convenient to apply to all sorts of potential forms. Furthermore, by means of the obtained results, we give explicit calculations for the one-dimensional electric potential. Project supported by the National Natural Science Foundation of China (Grant Nos. 11374360, 11405266, and 11505285) and the National Basic Research Program of China (Grant No. 2013CBA01504).

  11. Materialism across the lifespan : An age-period-cohort analysis

    NARCIS (Netherlands)

    Jaspers, Esther; Pieters, Rik

    2016-01-01

    This research examined the development of materialism across the lifespan. Two initial studies revealed that: 1) lay beliefs were that materialism declines with age; and 2) previous research findings also implied a modest, negative relationship between age and materialism. Yet, previous research has

  12. Information dynamics and open systems classical and quantum approach

    CERN Document Server

    Ingarden, R S; Ohya, M

    1997-01-01

    This book aims to present an information-theoretical approach to thermodynamics and its generalisations On the one hand, it generalises the concept of `information thermodynamics' to that of `information dynamics' in order to stress applications outside thermal phenomena On the other hand, it is a synthesis of the dynamics of state change and the theory of complexity, which provide a common framework to treat both physical and nonphysical systems together Both classical and quantum systems are discussed, and two appendices are included to explain principal definitions and some important aspects of the theory of Hilbert spaces and operator algebras The concept of higher-order temperatures is explained and applied to biological and linguistic systems The theory of open systems is presented in a new, much more general form Audience This volume is intended mainly for theoretical and mathematical physicists, but also for mathematicians, experimental physicists, physical chemists, theoretical biologists, communicat...

  13. Methodology Approaches Regarding Classic versus Mobile Enterprise Application Development

    Directory of Open Access Journals (Sweden)

    Vasile-Daniel PAVALOAIA

    2013-01-01

    Full Text Available In the nowadays enterprise computerized context, there is a trend that shifts the business ap-plications to the new mobile environments. In the light of this information, it is highly important to be knowledgeable about the software development methodologies available in order to make the right choice when it comes to developing a mobile application. The current research aims to presenting the methodological approaches regarding the development cycle of classic enterprise software versus mobile apps. In the first part of the paper a brief literature review regarding the mobile apps is made, for the purpose of justifying the current research theme. The most consistent part of the article puts face-to-face the “classical” and the new development methodologies adapted to the requirements of the new mobile environment trends. The paper also presents the challenges and limitations of mobile applications as well as few of the future trends in the researched domain.

  14. A Unified Algebraic Approach to Classical Yang-Baxter Equation

    OpenAIRE

    Bai, Chengming

    2007-01-01

    In this paper, the different operator forms of classical Yang-Baxter equation are given in the tensor expression through a unified algebraic method. It is closely related to left-symmetric algebras which play an important role in many fields in mathematics and mathematical physics. By studying the relations between left-symmetric algebras and classical Yang-Baxter equation, we can construct left-symmetric algebras from certain classical r-matrices and conversely, there is a natural classical ...

  15. A real options approach to a classical capacity expansion problem

    Directory of Open Access Journals (Sweden)

    Antonio G. N. Novaes

    2005-08-01

    Full Text Available Some authors, considering deterministic or stochastic demand patterns and different forecasting formulations, have studied the classical problem of optimally meeting a growing demand for capacity, over an infinite horizon. With this approach, only investment costs discounted with a predefined interest rate are considered in the analysis. Adding other expenditures and revenues, managers usually estimate the discounted cash flow of the project, and assume the organization will follow a predetermined plan when investing, regardless of how events unfold in the future. The real options approach, on the other hand, introduces the possibility of incorporating other decision alternatives in the economic analysis, such as the option of waiting or postponing, abandoning, switching, etc. In this paper we first review the classical capacity expansion models. Then, the concepts and properties of the real options approach, with emphasis on the Black-Scholes equation, are briefly discussed. Finally, an application example is presented and discussed.Alguns autores vêm estudando o problema clássico de atender otimamente a demanda por capacidade crescente ao longo de um horizonte infinito, considerando, para isso, formas determinísticas ou estocásticas de expansão da demanda, bem como diferentes formulações de previsão. Com esse enfoque, somente os custos de investimento, descontados a uma taxa predefinida de juros, são considerados na análise. Adicionando outros desembolsos e receitas, os administradores usualmente estimam o fluxo de caixa descontado do projeto, admitindo que a empresa seguirá um plano predeterminado, independentemente da forma como os eventos se desenrolarão no futuro. O enfoque de opções reais, por outro lado, introduz a possibilidade de incorporar outras alternativas de decisão na análise econômica, tais como a opção de esperar ou postergar, abandonar, trocar, etc. Neste artigo se faz, em primeiro lugar, uma revisão dos

  16. Numerical approaches to complex quantum, semiclassical and classical systems

    International Nuclear Information System (INIS)

    In this work we analyse the capabilities of several numerical techniques for the description of different physical systems. Thereby, the considered systems range from quantum over semiclassical to classical and from few- to many-particle systems. In chapter 1 we investigate the behaviour of a single quantum particle in the presence of an external disordered background (static potentials). Starting from the quantum percolation problem, we address the fundamental question of a disorder induced (Anderson-) transition from extended to localised single-particle eigenstates. Distinguishing isolating from conducting states by applying a local distribution approach for the local density of states (LDOS), we detect the quantum percolation threshold in two- and three-dimensions. Extending the quantum percolation model to a quantum random resistor model, we comment on the possible relevance of our results to the influence of disorder on the conductivity in graphene sheets. For the calculation of the LDOS as well as for the Chebyshev expansion of the time evolution operator, the kernel polynomial method (KPM) is the key numerical technique. In chapter 2 we examine how a single quantum particle is influenced by retarded bosonic fields that are inherent to the system. Within the Holstein model, these bosonic degrees of freedom (phonons) give rise to an infinite dimensional Hilbert space, posing a true many-particle problem. Constituting a minimal model for polaron formation, the Holstein model allows us to study the optical absorption and activated transport in polaronic systems. Using a two-dimensional variant of the KPM, we calculate for the first time quasi-exactly the optical absorption and dc-conductivity as a function of temperature. In chapter 3 we come back to the time evolution of a quantum particle in an external, static potential and investigate the capability of semiclassical approximations to it. We address basic quantum effects as tunneling, interference and

  17. Numerical approaches to complex quantum, semiclassical and classical systems

    Energy Technology Data Exchange (ETDEWEB)

    Schubert, Gerald

    2008-11-03

    In this work we analyse the capabilities of several numerical techniques for the description of different physical systems. Thereby, the considered systems range from quantum over semiclassical to classical and from few- to many-particle systems. In chapter 1 we investigate the behaviour of a single quantum particle in the presence of an external disordered background (static potentials). Starting from the quantum percolation problem, we address the fundamental question of a disorder induced (Anderson-) transition from extended to localised single-particle eigenstates. Distinguishing isolating from conducting states by applying a local distribution approach for the local density of states (LDOS), we detect the quantum percolation threshold in two- and three-dimensions. Extending the quantum percolation model to a quantum random resistor model, we comment on the possible relevance of our results to the influence of disorder on the conductivity in graphene sheets. For the calculation of the LDOS as well as for the Chebyshev expansion of the time evolution operator, the kernel polynomial method (KPM) is the key numerical technique. In chapter 2 we examine how a single quantum particle is influenced by retarded bosonic fields that are inherent to the system. Within the Holstein model, these bosonic degrees of freedom (phonons) give rise to an infinite dimensional Hilbert space, posing a true many-particle problem. Constituting a minimal model for polaron formation, the Holstein model allows us to study the optical absorption and activated transport in polaronic systems. Using a two-dimensional variant of the KPM, we calculate for the first time quasi-exactly the optical absorption and dc-conductivity as a function of temperature. In chapter 3 we come back to the time evolution of a quantum particle in an external, static potential and investigate the capability of semiclassical approximations to it. We address basic quantum effects as tunneling, interference and

  18. Modern versus Tradition: Are There Two Different Approaches to Reading of the Confucian Classics?

    Science.gov (United States)

    Cheng, Chung-yi

    2016-01-01

    How to read the Confucian Classics today? Scholars with philosophical training usually emphasize that the philosophical approach, in comparison with the classicist and historical ones, is the best way to read the Confucian Classics, for it can dig out as much intellectual resources as possible from the classical texts in order to show their modern…

  19. AN ECLECTIC APPROACH TO THE EDUCATION OF THE CLASSICAL GUITAR

    OpenAIRE

    Muhittin OZDEMIR; A. Aylin CAN

    2014-01-01

    The purpose of this study was to examine whether teaching activities aimed to improve musical knowledge and skills of students, who took classical guitar lessons in individual instrument education classes, had an effect on the success of students’ performances. The study group of the research consisted of first year, second year and third year guitar students who took classical guitar courses within individual instrument education classes at Karadeniz Technical University, in the Music Educat...

  20. A classical approach to higher-derivative gravity

    International Nuclear Information System (INIS)

    Two classical routes towards higher-derivative gravity theory are described. The first one is a geometrical route, starting from first principles. The second route is a formal one, and is based on a recent theorem by Castagnino et.al. [J. Math. Phys. 28 (1987) 1854]. A cosmological solution of the higher-derivative field equations is exhibited which in a classical framework singles out this gravitation theory. (author)

  1. A Classical Approach to Multichromophoric Resonance Energy Transfer

    CERN Document Server

    Duque, Sebastian; Pachon, Leonardo A

    2014-01-01

    Enhanced rates in multichromophoric resonance energy transfer are shown to be well described by a classical theory based on classical electrodynamics. In a coupling configuration between $N_A$ acceptors and $N_D$ donors, the theory correctly predicts an enhancement of the energy transfer rate dependent on the total number of donor-acceptor pairs, $N_A N_D$. As an example, the theory, applied to the transfer rate in LH II, gives results in excellent agreement with experiment.

  2. Laban Movement Analysis Approach to Classical Ballet Pedagogy

    Science.gov (United States)

    Whittier, Cadence

    2006-01-01

    As a Certified Laban Movement Analyst and a classically trained ballet dancer, I consistently weave the Laban Movement Analysis/Bartenieff Fundamentals (LMA/BF) theories and philosophies into the ballet class. This integration assists in: (1) Identifying the qualitative movement elements both in the art of ballet and in the students' dancing…

  3. AN ECLECTIC APPROACH TO THE EDUCATION OF THE CLASSICAL GUITAR

    Directory of Open Access Journals (Sweden)

    Muhittin OZDEMIR

    2014-08-01

    Full Text Available The purpose of this study was to examine whether teaching activities aimed to improve musical knowledge and skills of students, who took classical guitar lessons in individual instrument education classes, had an effect on the success of students’ performances. The study group of the research consisted of first year, second year and third year guitar students who took classical guitar courses within individual instrument education classes at Karadeniz Technical University, in the Music Education branch of Fine Arts Education Department in the academic year of 2012-2013. The research was designed according to the model of experimental design with the control groups for pretests and posttests. After reviewing the equivalency of guitar students, experimental (N=7 and control (N=7 groups were selected with the help of the impartial assignment method. In research, while the experimental group was introduced with special guitar education lessons prepared according to the systematic education model, for two successive periods of five weeks each; the traditional teaching method was employed for the control group. Pretests and posttests were administered two both groups. Based on the results, it can be said that classical guitar performance successes of students in experimental group have increased to a greater degree than those in control group after the treatment. In conclusion, it was found that the special guitar education program, which aimed to increase musical and technical knowledge and skills in playing classical guitar, was significantly more effective and improving than the traditional teaching methods.

  4. Historical approach to Turkish folk and classical music

    Directory of Open Access Journals (Sweden)

    Fatma Adile Baser

    2006-08-01

    Full Text Available Turkish Classical Music, especially with the success at the Ottoman period, is a music of a civilization. It became a common language in all geographies and people that Turks made contacts with in various ways. Turkish civilization does not deny what she learned from Persians and Arabs, but she managed to use them to improve herself and developing better by adding the information to herself. This shows her power of creating civilization. One of the main signs of this three-continent-spread culture is of course Turkish Classical Music. İt is seen that collective awareness and mind which forms Turkish Classical Music, first recovered the common points, coming from the roots, between Turkish “boy” clans then considered the musical specialities of other societies that share same climate, geography, or some cultural values with Turks. In this manner, the music developed, came to the point that we say “classic”, in which societies and nations found themselves within, by climbing over the identity of being a particular group’s or society’s music. This study is directed towards to recover the main components which gives Turkish Classical Music its character in the process of development by looking beyond the history. In this point the relationship between Turkish Classical and Folk Music is presented.The main path to Muslim Turkishness in the art and political area – Oguz Turkishness is emphasized and their understanding and behaviour before and after Islam is discussed from the music side. Second mainland of Turks, Anatolia is again discussed under another title by the means of Seljuks, Anatolian Seljuks and Beyliks periods; reflections of Oguz “bey” understanding in music is told. The effects of the sufi understanding which came to Anatolia over Horasan on music and the Anatolian Turkishness’ role over sufi understanding is considered, Ahi organization which is said to be a semi religious foundation of Turkish style mentioned by

  5. Historical approach to Turkish folk and classical music

    Directory of Open Access Journals (Sweden)

    Fatma Âdile Başer

    2006-08-01

    Full Text Available Turkish Classical Music, especially with the success at the Ottoman period, is a music of a civilization. It became a common language in all geographies and people that Turks made contacts with in various ways. Turkish civilization does not deny what she learned from Persians and Arabs, but she managed to use them to improve herself and developing better by adding the information to herself. This shows her power of creating civilization. One of the main signs of this three-continent-spread culture is of course Turkish Classical Music. İt is seen that collective awareness and mind which forms Turkish Classical Music, first recovered the common points, coming from the roots, between Turkish “boy” clans then considered the musical specialities of other societies that share same climate, geography, or some cultural values with Turks. In this manner, the music developed, came to the point that we say “classic”, in which societies and nations found themselves within, by climbing over the identity of being a particular group’s or society’s music. This study is directed towards to recover the main components which gives Turkish Classical Music its character in the process of development by looking beyond the history. In this point the relationship between Turkish Classical and Folk Music is presented.The main path to Muslim Turkishness in the art and political area – Oguz Turkishness is emphasized and their understanding and behaviour before and after Islam is discussed from the music side. Second mainland of Turks, Anatolia is again discussed under another title by the means of Seljuks, Anatolian Seljuks and Beyliks periods; reflections of Oguz “bey” understanding in music is told. The effects of the sufi understanding which came to Anatolia over Horasan on music and the Anatolian Turkishness’ role over sufi understanding is considered, Ahi organization which is said to be a semi religious foundation of Turkish style mentioned by

  6. Hybrid quantum-classical approach to correlated materials

    OpenAIRE

    Bauer, Bela; Wecker, Dave; Millis, Andrew J.; Hastings, Matthew B.; Troyer, M.

    2015-01-01

    Recent improvements in control of quantum systems make it seem feasible to finally build a quantum computer within a decade. While it has been shown that such a quantum computer can in principle solve certain small electronic structure problems and idealized model Hamiltonians, the highly relevant problem of directly solving a complex correlated material appears to require a prohibitive amount of resources. Here, we show that by using a hybrid quantum-classical algorithm that incorporates the...

  7. A decoupling approach to classical data transmission over quantum channels

    DEFF Research Database (Denmark)

    Dupont-Dupuis, Fréderic; Szehr, Oleg; Tomamichel, Marco

    2014-01-01

    Most coding theorems in quantum Shannon theory can be proven using the decoupling technique. To send data through a channel, one guarantees that the environment gets no information about it. Uhlmann's theorem then ensures that the receiver must be able to decode. While a wide range of problems can......, which ensures that the environment is only classically correlated with the sent data. Our techniques naturally yield a generalization of the Holevo-Schumacher-Westmoreland theorem to the one-shot scenario, where a quantum channel can be applied only once....

  8. Worldline approach to semi-classical conformal blocks

    CERN Document Server

    Hijano, Eliot; Snively, River

    2015-01-01

    We extend recent results on semi-classical conformal blocks in 2d CFT and their relation to 3D gravity via the AdS/CFT correspondence. We consider four-point functions with two heavy and two light external operators, along with the exchange of a light operator. By explicit computation, we establish precise agreement between these CFT objects and a simple picture of particle worldlines joined by cubic vertices propagating in asymptotically AdS$_3$ geometries (conical defects or BTZ black holes). We provide a simple argument that explains this agreement.

  9. A semi-classical approach to radiation problems

    International Nuclear Information System (INIS)

    The article is mainly devoted to a detailed exposition of the method of solution of problems in magnetic resonance by transformations to rotating co-ordinate frames. The well-known method of transformation to a frame rotating at constant angular velocity has been extended to embrace modulated rotations, thereby allowing the elimination of oscillating fields of any strength. A detailed analysis of the Bloch-Siegert problem is given to illustrate the application of the techniques. Since the original work was carried out in relation to the study of excited atoms, the question naturally arose, how to deal with spontaneous emission. A general discussion of this question is given, and a technique is described which allows spontaneous emission to be included in semi-classical calculations of cycles of optical pumping. (Auth.)

  10. A Synthetic Approach to the Transfer Matrix Method in Classical and Quantum Physics

    Science.gov (United States)

    Pujol, O.; Perez, J. P.

    2007-01-01

    The aim of this paper is to propose a synthetic approach to the transfer matrix method in classical and quantum physics. This method is an efficient tool to deal with complicated physical systems of practical importance in geometrical light or charged particle optics, classical electronics, mechanics, electromagnetics and quantum physics. Teaching…

  11. Cleaning graphene: A first quantum/classical molecular dynamics approach

    Science.gov (United States)

    Delfour, L.; Davydova, A.; Despiau-Pujo, E.; Cunge, G.; Graves, D. B.; Magaud, L.

    2016-03-01

    Graphene outstanding properties created a huge interest in the condensed matter community and unprecedented fundings at the international scale in the hope of application developments. Recently, there have been several reports of incomplete removal of the polymer resists used to transfer as-grown graphene from one substrate to another, resulting in altered graphene transport properties. Finding a large-scale solution to clean graphene from adsorbed residues is highly desirable and one promising possibility would be to use hydrogen plasmas. In this spirit, we couple here quantum and classical molecular dynamics simulations to explore the kinetic energy ranges required by atomic hydrogen to selectively etch a simple residue—a CH3 group—without irreversibly damaging the graphene. For incident energies in the 2-15 eV range, the CH3 radical can be etched by forming a volatile CH4 compound which leaves the surface, either in the CH4 form or breaking into CH3 + H fragments, without further defect formation. At this energy, adsorption of H atoms on graphene is possible and further annealing will be required to recover pristine graphene.

  12. Rabbit Models of Ocular Diseases: New Relevance for Classical Approaches.

    Science.gov (United States)

    Zernii, Evgeni Y; Baksheeva, Viktoriia E; Iomdina, Elena N; Averina, Olga A; Permyakov, Sergei E; Philippov, Pavel P; Zamyatnin, Andrey A; Senin, Ivan I

    2016-01-01

    Over 100 million individuals are affected by irreversible visual impairments and blindness worldwide, while ocular diseases remain a challenging problem despite significant advances in modern ophthalmology. Development of novel drugs and drug delivery mechanisms, as well as advanced ophthalmological techniques requires experimental models including animals, capable of developing ocular diseases with similar etiology and pathology, suitable for future trials of new therapeutic approaches. Although experimental ophthalmology and visual research are traditionally performed on rodent models, these animals are often unsuitable for pre-clinical drug efficacy and safety studies, as well as for testing novel drug delivery approaches, e.g. controlled release of pharmaceuticals using intra-ocular implants. Therefore, rabbit models of ocular diseases are particularly useful in this context, since rabbits can be easily handled, while sharing more common anatomical and biochemical features with humans compared to rodents, including longer life span and larger eye size. This review provides a brief description of clinical, morphological and mechanistic aspects of the most common ocular diseases (dry eye syndrome, glaucoma, age-related macular degeneration, light-induced retinopathies, cataract and uveitis) and summarizes the diversity of current strategies for their experimental modeling in rabbits. Several applications of some of these models in ocular pharmacology and eye care strategies are also discussed. PMID:26553163

  13. Semi-classical approach to quantum black holes

    CERN Document Server

    Spallucci, Euro

    2014-01-01

    In this Chapter we would like to review a "~phenomenological~" approach taking into account the most fundamental feature of string theory or, more in general, of quantum gravity, whatever its origin, which is the existence of a minimal length in the space-time fabric. This length is generally identified with the Planck length, or the string length, but it could be also much longer down to the TeV region. A simple and effective way to keep track of the effects the minimal length in black hole geometries is to solve the Einstein equations with an energy momentum tensor describing non point-like matter. The immediate consequence is the absence of any curvature singularity. Where textbook solutions of the Einstein equations loose any physical meaning because of infinite tidal forces, we find a de Sitter vacuum core of high, but finite, energy density and pressure. An additional improvement regards the final stage of the black hole evaporation leading to a vanishing Hawking temperature even in the neutral, non-rot...

  14. A coupled-trajectory quantum-classical approach to decoherence in non-adiabatic processes

    CERN Document Server

    Min, Seung Kyu; Gross, E K U

    2015-01-01

    We present a novel quantum-classical approach to non-adiabatic dynamics, deduced from the coupled electronic and nuclear equations in the framework of the exact factorization of the electron-nuclear wave function. The method is based on the quasi-classical interpretation of the nuclear wave function, whose phase is related to the classical momentum and whose density is represented in terms of classical trajectories. In this approximation, electronic decoherence is naturally induced as effect of the coupling to the nuclei and correctly reproduces the expected quantum behaviour. Moreover, the splitting of the nuclear wave packet is captured as consequence of the correct approximation of the time-dependent potential of the theory. This new approach offers a clear improvement over Ehrenfest-like dynamics. The theoretical derivation presented in the Letter is supported by numerical results that are compared to quantum mechanical calculations.

  15. Does classical liberalism imply an evolutionary approach to policy-making?

    OpenAIRE

    Schnellenbach, Jan

    2014-01-01

    This paper argues that an evolutionary approach to policy-making, which emphasizes openness to change and political variety, is particularly compatible with the central tenets of classical liberalism. The chief reasons are that classical liberalism acknowledges the ubiquity of uncertainty, as well as heterogeneity in preferences and beliefs, and generally embraces gradual social and economic change that arises from accidental variation rather than deliberate, large-scale planning. In contrast...

  16. A synthetic approach to the transfer matrix method in classical and quantum physics

    International Nuclear Information System (INIS)

    The aim of this paper is to propose a synthetic approach to the transfer matrix method in classical and quantum physics. This method is an efficient tool to deal with complicated physical systems of practical importance in geometrical light or charged particle optics, classical electronics, mechanics, electromagnetics and quantum physics. Teaching would benefit by using the abcd-matrix which in addition is easy to implement on a personal computer

  17. A synthetic approach to the transfer matrix method in classical and quantum physics

    Science.gov (United States)

    Pujol, O.; Pérez, J. P.

    2007-07-01

    The aim of this paper is to propose a synthetic approach to the transfer matrix method in classical and quantum physics. This method is an efficient tool to deal with complicated physical systems of practical importance in geometrical light or charged particle optics, classical electronics, mechanics, electromagnetics and quantum physics. Teaching would benefit by using the abcd-matrix which in addition is easy to implement on a personal computer.

  18. Coupled-Trajectory Quantum-Classical Approach to Electronic Decoherence in Nonadiabatic Processes

    Science.gov (United States)

    Min, Seung Kyu; Agostini, Federica; Gross, E. K. U.

    2015-08-01

    We present a novel quantum-classical approach to nonadiabatic dynamics, deduced from the coupled electronic and nuclear equations in the framework of the exact factorization of the electron-nuclear wave function. The method is based on the quasiclassical interpretation of the nuclear wave function, whose phase is related to the classical momentum and whose density is represented in terms of classical trajectories. In this approximation, electronic decoherence is naturally induced as an effect of the coupling to the nuclei and correctly reproduces the expected quantum behavior. Moreover, the splitting of the nuclear wave packet is captured as a consequence of the correct approximation of the time-dependent potential of the theory. This new approach offers a clear improvement over Ehrenfest-like dynamics. The theoretical derivation presented in this Letter is supported by numerical results that are compared to quantum mechanical calculations.

  19. Cosmology with quantum matter and a classical gravitational field: the approach of configuration-space ensembles

    CERN Document Server

    Reginatto, Marcel

    2013-01-01

    I consider the formulation of hybrid cosmological models that consists of a classical gravitational field interacting with a quantized massive scalar field in the formalism of ensembles on configuration space. This is a viable approach that provides an alternative to semiclassical gravity. I discuss a particular, highly nonclassical solution in two approximations, minisuperspace and spherically-symmetric midisuperspace. In both cases, the coupling of the quantum scalar field and classical gravitational field leads to a cosmological model which has a quantized radius of the universe.

  20. SPRED: A machine learning approach for the identification of classical and non-classical secretory proteins in mammalian genomes

    International Nuclear Information System (INIS)

    Eukaryotic protein secretion generally occurs via the classical secretory pathway that traverses the ER and Golgi apparatus. Secreted proteins usually contain a signal sequence with all the essential information required to target them for secretion. However, some proteins like fibroblast growth factors (FGF-1, FGF-2), interleukins (IL-1 alpha, IL-1 beta), galectins and thioredoxin are exported by an alternative pathway. This is known as leaderless or non-classical secretion and works without a signal sequence. Most computational methods for the identification of secretory proteins use the signal peptide as indicator and are therefore not able to identify substrates of non-classical secretion. In this work, we report a random forest method, SPRED, to identify secretory proteins from protein sequences irrespective of N-terminal signal peptides, thus allowing also correct classification of non-classical secretory proteins. Training was performed on a dataset containing 600 extracellular proteins and 600 cytoplasmic and/or nuclear proteins. The algorithm was tested on 180 extracellular proteins and 1380 cytoplasmic and/or nuclear proteins. We obtained 85.92% accuracy from training and 82.18% accuracy from testing. Since SPRED does not use N-terminal signals, it can detect non-classical secreted proteins by filtering those secreted proteins with an N-terminal signal by using SignalP. SPRED predicted 15 out of 19 experimentally verified non-classical secretory proteins. By scanning the entire human proteome we identified 566 protein sequences potentially undergoing non-classical secretion. The dataset and standalone version of the SPRED software is available at (http://www.inb.uni-luebeck.de/tools-demos/spred/spred).

  1. Automatic processing of gamma ray spectra employing classical and modified Fourier transform approach

    International Nuclear Information System (INIS)

    This report describes methods for automatic processing of gamma ray spectra acquired with HPGe detectors. The processing incorporated both classical and signal processing approach. The classical method was used for smoothing, detecting significant peaks, finding peak envelope limits and a proposed method of finding peak limits, peak significance index, full width at half maximum, detecting doublets for further analysis. To facilitate application of signal processing to nuclear spectra, Madan et al. gave a new classification of signals and identified nuclear spectra as Type II signals, mathematically formalized modified Fourier transform and pioneered its application to process doublet envelopes acquired with modern spectrometers. It was extended to facilitate routine analysis of the spectra. A facility for energy and efficiency calibration was also included. The results obtained by analyzing observed gamma-ray spectra using the above approach compared favourably with those obtained with SAMPO and also those derived from table of radioisotopes. (author). 15 refs., 3 figs., 3 tabs

  2. Classical hybrid approaches on a transportation problem with gas emissions constraints

    OpenAIRE

    Pintea, Camelia-M.; Pop, Petrica C.; Hajdu-Macelaru, Mara

    2012-01-01

    In order to keep a green planet, in particular its important to limiting the pollution with gas emissions. In a specific capacitated fixed-charge transportation problem with fixed capacities for distribution centers and customers with particular demands, the objective is to keep the pollution factor in a given range while the total cost of the transportation is as low as possible. In order to solve this problem, we developed several hybrid variants of the nearest neighbor classical approach. ...

  3. Design and analysis of experiments classical and regression approaches with SAS

    CERN Document Server

    Onyiah, Leonard C

    2008-01-01

    Introductory Statistical Inference and Regression Analysis Elementary Statistical Inference Regression Analysis Experiments, the Completely Randomized Design (CRD)-Classical and Regression Approaches Experiments Experiments to Compare Treatments Some Basic Ideas Requirements of a Good Experiment One-Way Experimental Layout or the CRD: Design and Analysis Analysis of Experimental Data (Fixed Effects Model) Expected Values for the Sums of Squares The Analysis of Variance (ANOVA) Table Follow-Up Analysis to Check fo

  4. Semiclassical approach to mesoscopic systems. Classical trajectory correlations and wave interface

    Energy Technology Data Exchange (ETDEWEB)

    Waltner, Daniel [Regensburg Univ. (Germany). Institut fuer Theoretische Physik

    2012-07-01

    This volume describes mesoscopic systems with classically chaotic dynamics using semiclassical methods which combine elements of classical dynamics and quantum interference effects. Experiments and numerical studies show that Random Matrix Theory (RMT) explains physical properties of these systems well. This was conjectured more than 25 years ago by Bohigas, Giannoni and Schmit for the spectral properties. Since then, it has been a challenge to understand this connection analytically. The author offers his readers a clearly-written and up-to-date treatment of the topics covered. He extends previous semiclassical approaches that treated spectral and conductance properties. He shows that RMT results can in general only be obtained semiclassically when taking into account classical configurations not considered previously, for example those containing multiply traversed periodic orbits. Furthermore, semiclassics is capable of describing effects beyond RMT. In this context he studies the effect of a non-zero Ehrenfest time, which is the minimal time needed for an initially spatially localized wave packet to show interference. He derives its signature on several quantities characterizing mesoscopic systems, e. g. dc and ac conductance, dc conductance variance, n-pair correlation functions of scattering matrices and the gap in the density of states of Andreev billiards. (orig.)

  5. Cartan-Calculus and its Generalizations via a Path-Integral Approach to Classical Mechanics

    CERN Document Server

    Gozzi, E

    1997-01-01

    In this paper we review the recently proposed path-integral counterpart of the Koopman-von Neumann operatorial approach to classical Hamiltonian mechanics. We identify in particular the geometrical variables entering this formulation and show that they are essentially a basis of the cotangent bundle to the tangent bundle to phase-space. In this space we introduce an extended Poisson brackets structure which allows us to re-do all the usual Cartan calculus on symplectic manifolds via these brackets. We also briefly sketch how the Schouten-Nijenhuis, the Frölicher- Nijenhuis and the Nijenhuis-Richardson brackets look in our formalism.

  6. Experimental demonstration of a classical approach for flexible space structure control: NASA CSI testbeds

    Science.gov (United States)

    Bond, Wie

    1991-01-01

    The results of active control experiments performed for the Mini-Mast truss structure are presented. The primary research objectives were: (1) to develop active structural control concepts and/or techniques; (2) to verify the concept of robust non-minimum-phase compensation for a certain class of non-colocated structural control problems through ground experiments; (3) to verify a 'dipole' concept for persistent disturbance rejection control of flexible structures; and (4) to identify CSI (Control Structure Interaction) issues and areas of emphasis for the next generation of large flexible spacecraft. The classical SISO (Single Input and Single Output) control design approach was employed.

  7. On the relevance of assumptions associated with classical factor analytic approaches

    Directory of Open Access Journals (Sweden)

    Daniel eKasper

    2013-03-01

    Full Text Available A personal trait, for example a person's cognitive ability, represents a theoretical concept postulated to explain behavior. Interesting constructs are latent, that is, they cannot be observed. Latent variable modeling constitutes a methodology to deal with hypothetical constructs. Constructs are modeled as random variables and become components of a statistical model. As random variables, they possess a probability distribution in the population of reference. In applications, this distribution is typically assumed to be the normal distribution. The normality assumption may be reasonable in many cases, but there are situations where it cannot be justified. For example, this is true for criterion-referenced tests or for background characteristics of students in large scale assessment studies. Nevertheless, the normal procedures in combination with the classical factor analytic methods are frequently pursued, despite the effects of violating this ``implicit'' assumption are not clear in general.In a simulation study, we investigate whether classical factor analytic approaches can be instrumental in estimating the factorial structure and properties of the population distribution of a latent personal trait from educational test data, when violations of classical assumptions as the aforementioned are present. The results indicate that having a latent non-normal distribution clearly affects the estimation of the distribution of the factor scores and properties thereof. Thus, when the population distribution of a personal trait is assumed to be non-symmetric, we recommend avoiding those factor analytic approaches for estimation of a person's factor score, even though the number of extracted factors and the estimated loading matrix may not be strongly affected.An application to the Progress in International Reading Literacy Study (PIRLS is given. Comments on possible implications for the Programme for International Student Assessment (PISA complete the

  8. On the relevance of assumptions associated with classical factor analytic approaches.

    Science.gov (United States)

    Kasper, Daniel; Unlü, Ali

    2013-01-01

    A personal trait, for example a person's cognitive ability, represents a theoretical concept postulated to explain behavior. Interesting constructs are latent, that is, they cannot be observed. Latent variable modeling constitutes a methodology to deal with hypothetical constructs. Constructs are modeled as random variables and become components of a statistical model. As random variables, they possess a probability distribution in the population of reference. In applications, this distribution is typically assumed to be the normal distribution. The normality assumption may be reasonable in many cases, but there are situations where it cannot be justified. For example, this is true for criterion-referenced tests or for background characteristics of students in large scale assessment studies. Nevertheless, the normal procedures in combination with the classical factor analytic methods are frequently pursued, despite the effects of violating this "implicit" assumption are not clear in general. In a simulation study, we investigate whether classical factor analytic approaches can be instrumental in estimating the factorial structure and properties of the population distribution of a latent personal trait from educational test data, when violations of classical assumptions as the aforementioned are present. The results indicate that having a latent non-normal distribution clearly affects the estimation of the distribution of the factor scores and properties thereof. Thus, when the population distribution of a personal trait is assumed to be non-symmetric, we recommend avoiding those factor analytic approaches for estimation of a person's factor score, even though the number of extracted factors and the estimated loading matrix may not be strongly affected. An application to the Progress in International Reading Literacy Study (PIRLS) is given. Comments on possible implications for the Programme for International Student Assessment (PISA) complete the presentation. PMID

  9. Complementary approaches to diagnosing marine diseases: a union of the modern and the classic

    Science.gov (United States)

    Burge, Colleen A.; Friedman, Carolyn S.; Getchell, Rodman G.; House, Marcia; Lafferty, Kevin D.; Mydlarz, Laura D.; Prager, Katherine C.; Sutherland, Kathryn P.; Renault, Tristan; Kiryu, Ikunari; Vega-Thurber, Rebecca

    2016-01-01

    Linking marine epizootics to a specific aetiology is notoriously difficult. Recent diagnostic successes show that marine disease diagnosis requires both modern, cutting-edge technology (e.g. metagenomics, quantitative real-time PCR) and more classic methods (e.g. transect surveys, histopathology and cell culture). Here, we discuss how this combination of traditional and modern approaches is necessary for rapid and accurate identification of marine diseases, and emphasize how sole reliance on any one technology or technique may lead disease investigations astray. We present diagnostic approaches at different scales, from the macro (environment, community, population and organismal scales) to the micro (tissue, organ, cell and genomic scales). We use disease case studies from a broad range of taxa to illustrate diagnostic successes from combining traditional and modern diagnostic methods. Finally, we recognize the need for increased capacity of centralized databases, networks, data repositories and contingency plans for diagnosis and management of marine disease.

  10. Numerical study of chiral plasma instability within the classical statistical field theory approach

    Science.gov (United States)

    Buividovich, P. V.; Ulybyshev, M. V.

    2016-07-01

    We report on a numerical study of real-time dynamics of electromagnetically interacting chirally imbalanced lattice Dirac fermions within the classical statistical field theory approach. Namely, we perform exact simulations of the real-time quantum evolution of fermionic fields coupled to classical electromagnetic fields, which are in turn coupled to the vacuum expectation value of the fermionic electric current. We use Wilson-Dirac Hamiltonian for fermions, and noncompact action for the gauge field. In general, we observe that the backreaction of fermions on the electromagnetic field prevents the system from acquiring chirality imbalance. In the case of chirality pumping in parallel electric and magnetic fields, the electric field is screened by the produced on-shell fermions and the accumulation of chirality is hence stopped. In the case of evolution with initially present chirality imbalance, axial charge tends to transform to helicity of the electromagnetic field. By performing simulations on large lattices we show that in most cases this decay process is accompanied by the inverse cascade phenomenon, which transfers energy from short-wavelength to long-wavelength electromagnetic fields. In some simulations, however, we observe a very clear signature of inverse cascade for the helical magnetic fields that is not accompanied by the axial charge decay. This suggests that the relation between the inverse cascade and axial charge decay is not as straightforward as predicted by the simplest form of anomalous Maxwell equations.

  11. Time-calibrated phylogenomics of the classical swine fever viruses: genome-wide bayesian coalescent approach.

    Directory of Open Access Journals (Sweden)

    Taehyung Kwon

    Full Text Available The phylogeny of classical swine fever virus (CSFV, the causative agent of classical swine fever (CSF, has been investigated extensively. However, no evolutionary research has been performed using the whole CSFV genome. In this study, we used 37 published genome sequences to investigate the time-calibrated phylogenomics of CSFV. In phylogenomic trees based on Bayesian inference (BI and Maximum likelihood (ML, the 37 isolates were categorized into five genetic types (1.1, 1.2, 2.1, 2.3, and 3.4. Subgenotype 1.1 is divided into 3 groups and 1 unclassified isolate, 2.1 into 4 groups, 2.3 into 2 groups and 1 unclassified isolate, and subgenotype 1.2 and 3.4 consisted of one isolate each. We did not observe an apparent temporal or geographical relationship between isolates. Of the 14 genomic regions, NS4B showed the most powerful phylogenetic signal. Results of this evolutionary study using Bayesian coalescent approach indicate that CSFV has evolved at a rate of 13×.010-4 substitutions per site per year. The most recent common ancestor of CSFV appeared 2770.2 years ago, which was about 8000 years after pig domestication. The effective population size of CSFV underwent a slow increase until the 1950s, after which it has remained constant.

  12. Time-calibrated phylogenomics of the classical swine fever viruses: genome-wide bayesian coalescent approach.

    Science.gov (United States)

    Kwon, Taehyung; Yoon, Sook Hee; Kim, Kyu-Won; Caetano-Anolles, Kelsey; Cho, Seoae; Kim, Heebal

    2015-01-01

    The phylogeny of classical swine fever virus (CSFV), the causative agent of classical swine fever (CSF), has been investigated extensively. However, no evolutionary research has been performed using the whole CSFV genome. In this study, we used 37 published genome sequences to investigate the time-calibrated phylogenomics of CSFV. In phylogenomic trees based on Bayesian inference (BI) and Maximum likelihood (ML), the 37 isolates were categorized into five genetic types (1.1, 1.2, 2.1, 2.3, and 3.4). Subgenotype 1.1 is divided into 3 groups and 1 unclassified isolate, 2.1 into 4 groups, 2.3 into 2 groups and 1 unclassified isolate, and subgenotype 1.2 and 3.4 consisted of one isolate each. We did not observe an apparent temporal or geographical relationship between isolates. Of the 14 genomic regions, NS4B showed the most powerful phylogenetic signal. Results of this evolutionary study using Bayesian coalescent approach indicate that CSFV has evolved at a rate of 13×.010-4 substitutions per site per year. The most recent common ancestor of CSFV appeared 2770.2 years ago, which was about 8000 years after pig domestication. The effective population size of CSFV underwent a slow increase until the 1950s, after which it has remained constant. PMID:25815768

  13. An enhanced classical approach to graph isomorphism using continuous-time quantum walk

    International Nuclear Information System (INIS)

    Studies on graph isomorphism play an important role in graph research, and graph isomorphism algorithms have a wide range of applications in image matching, pattern recognition, computer vision, biochemistry and other fields. Previous research demonstrated that involving discrete-time quantum walk in the graph isomorphism algorithm could achieve complexity O(N7) for general graphs, since quantum walk could be utilized as a new toolbox for solving graph problems. We develop an enhanced classical approach to graph isomorphism using continuous-time quantum walk, which has lower complexity O(N5) and can effectively distinguish the graphs that are generally considered difficult. In addition, we define a graph similarity measure based on the proposed algorithm, which can be used for graph isomorphism and graph clustering. In the experiment, we test a wide variety of classes of graphs; the results show that the algorithm has a wide range of applications rather than being limited to a specific type of graph. (paper)

  14. A classical Master equation approach to modeling an artificial protein motor

    International Nuclear Information System (INIS)

    Inspired by biomolecular motors, as well as by theoretical concepts for chemically driven nanomotors, there is significant interest in constructing artificial molecular motors. One driving force is the opportunity to create well-controlled model systems that are simple enough to be modeled in detail. A remaining challenge is the fact that such models need to take into account processes on many different time scales. Here we describe use of a classical Master equation approach, integrated with input from Langevin and molecular dynamics modeling, to stochastically model an existing artificial molecular motor concept, the Tumbleweed, across many time scales. This enables us to study how interdependencies between motor processes, such as center-of-mass diffusion and track binding/unbinding, affect motor performance. Results from our model help guide the experimental realization of the proposed motor, and potentially lead to insights that apply to a wider class of molecular motors.

  15. Non-Kolmogorovian Approach to the Context-Dependent Systems Breaking the Classical Probability Law

    Science.gov (United States)

    Asano, Masanari; Basieva, Irina; Khrennikov, Andrei; Ohya, Masanori; Yamato, Ichiro

    2013-07-01

    There exist several phenomena breaking the classical probability laws. The systems related to such phenomena are context-dependent, so that they are adaptive to other systems. In this paper, we present a new mathematical formalism to compute the joint probability distribution for two event-systems by using concepts of the adaptive dynamics and quantum information theory, e.g., quantum channels and liftings. In physics the basic example of the context-dependent phenomena is the famous double-slit experiment. Recently similar examples have been found in biological and psychological sciences. Our approach is an extension of traditional quantum probability theory, and it is general enough to describe aforementioned contextual phenomena outside of quantum physics.

  16. Classical and quantum mechanics of complex Hamiltonian systems: An extended complex phase space approach

    Indian Academy of Sciences (India)

    R S Kaushal

    2009-08-01

    Certain aspects of classical and quantum mechanics of complex Hamiltonian systems in one dimension investigated within the framework of an extended complex phase space approach, characterized by the transformation = 1 + 2, = 1 + 2, are revisited. It is argued that Carl Bender inducted $\\mathcal{PT}$ symmetry in the studies of complex power potentials as a particular case of the present general framework in which two additional degrees of freedom are produced by extending each coordinate and momentum into complex planes. With a view to account for the subjective component of physical reality inherent in the collected data, e.g., using a Chevreul (hand-held) pendulum, a generalization of the Hamilton’s principle of least action is suggested.

  17. A New Wine Tasting Approach Based on Emotional Responses to Rapidly Recognize Classic European Wine Styles

    Directory of Open Access Journals (Sweden)

    Virgílio Loureiro

    2016-03-01

    Full Text Available Conventional tasting sheets are widely used to evaluate wine quality in wine tasting competitions. However, the higher scores are mostly obtained by international commercial wines, resulting in lower scores being awarded to the classic European wines. We hypothesize that this is due to the tasting methodology that fails to recognize this wine style. Therefore, the purpose of this work was to show the implementation of a new wine tasting approach to overcome this drawback. The proposed training technique is based on the emotional responses of the taster after smelling two wines of clearly opposite styles. The first wine is characterized by high aromatic intensity but low in-mouth intensity, perceived as disappointing to the taster, here defined as an “easy” wine. The second wine is characterized as a wine with low aromatic intensity but that provides an unexpectedly positive in-mouth experience, here defined as a “difficult” wine. These emotions are explained by the wine sensorial characteristics. The “easy” wine has an intense, simple smell with short persistence while the “difficult” wine has a low intensity, complex aroma, and long persistence. The first style corresponds to the international commercial wines most prized in international wine challenges. The second, frequently rejected by untrained tasters, is consistent with the “so called” classic European wines, and is characterized by light red or yellow straw colors, weak smell intensity, and aggressive mouth-feel. After no more than four training sessions and using the OIV tasting sheet, inexperienced tasters were able to score “difficult” wines equally as “easy” wines and understand their different attributes. In conclusion, this new tasting approach may be used by wine professionals to explain the characteristics of high quality wines that are not easily recognized by untrained consumers.

  18. On the hypothesis that quantum mechanism manifests classical mechanics: Numerical approach to the correspondence in search of quantum chaos

    International Nuclear Information System (INIS)

    Quantum manifestation of classical chaos has been one of the extensively studied subjects for more than a decade. Yet clear understanding of its nature still remains to be an open question partly due to the lack of a canonical definition of quantum chaos. The classical definition seems to be unsuitable in quantum mechanics partly because of the Heisenberg quantum uncertainty. In this regard, quantum chaos is somewhat misleading and needs to be clarified at the very fundamental level of physics. Since it is well known that quantum mechanics is more fundamental than classical mechanics, the quantum description of classically chaotic nature should be attainable in the limit of large quantum numbers. The focus of my research, therefore, lies on the correspondence principle for classically chaotic systems. The chaotic damped driven pendulum is mainly studied numerically using the split operator method that solves the time-dependent Schroedinger equation. For classically dissipative chaotic systems in which (multi)fractal strange attractors often emerge, several quantum dissipative mechanisms are also considered. For instance, Hoover's and Kubo-Fox-Keizer's approaches are studied with some computational analyses. But the notion of complex energy with non-Hermiticity is extensively applied. Moreover, the Wigner and Husimi distribution functions are examined with an equivalent classical distribution in phase-space, and dynamical properties of the wave packet in configuration and momentum spaces are also explored. The results indicate that quantum dynamics embraces classical dynamics although the classicalquantum correspondence fails to be observed in the classically chaotic regime. Even in the semi-classical limits, classically chaotic phenomena would eventually be suppressed by the quantum uncertainty

  19. On the hypothesis that quantum mechanism manifests classical mechanics: Numerical approach to the correspondence in search of quantum chaos

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sang-Bong

    1993-09-01

    Quantum manifestation of classical chaos has been one of the extensively studied subjects for more than a decade. Yet clear understanding of its nature still remains to be an open question partly due to the lack of a canonical definition of quantum chaos. The classical definition seems to be unsuitable in quantum mechanics partly because of the Heisenberg quantum uncertainty. In this regard, quantum chaos is somewhat misleading and needs to be clarified at the very fundamental level of physics. Since it is well known that quantum mechanics is more fundamental than classical mechanics, the quantum description of classically chaotic nature should be attainable in the limit of large quantum numbers. The focus of my research, therefore, lies on the correspondence principle for classically chaotic systems. The chaotic damped driven pendulum is mainly studied numerically using the split operator method that solves the time-dependent Schroedinger equation. For classically dissipative chaotic systems in which (multi)fractal strange attractors often emerge, several quantum dissipative mechanisms are also considered. For instance, Hoover`s and Kubo-Fox-Keizer`s approaches are studied with some computational analyses. But the notion of complex energy with non-Hermiticity is extensively applied. Moreover, the Wigner and Husimi distribution functions are examined with an equivalent classical distribution in phase-space, and dynamical properties of the wave packet in configuration and momentum spaces are also explored. The results indicate that quantum dynamics embraces classical dynamics although the classicalquantum correspondence fails to be observed in the classically chaotic regime. Even in the semi-classical limits, classically chaotic phenomena would eventually be suppressed by the quantum uncertainty.

  20. A formal derivation of the Gibbs entropy for classical systems following the Schroedinger quantum mechanical approach

    International Nuclear Information System (INIS)

    In the traditional statistical mechanics textbooks, the entropy concept is first introduced for the microcanonical ensemble and then extended to the canonical and grand-canonical cases. However, in the authors' experience, this procedure makes it difficult for the student to see the bigger picture and, although quite ingenuous, the subtleness of the demonstrations to pass from the microcanonical to the canonical and grand-canonical ensembles is hard to grasp. In the present work, we adapt the approach used by Schroedinger to introduce the entropy definition for quantum mechanical systems to derive a classical mechanical entropy definition, which is valid for all ensembles and is in complete agreement with the Gibbs entropy. Afterwards, we show how the specific probability densities for the microcanonical and canonical ensembles can be obtained from the system macrostate, the entropy definition and the second law of thermodynamics. After teaching the approach introduced in this paper for several years, we have found that it allows a better understanding of the statistical mechanics foundations. On the other hand, since it demands previous knowledge of thermodynamics and mathematical analysis, in our experience this approach is more adequate for final-year undergraduate and graduate physics students

  1. A formal derivation of the Gibbs entropy for classical systems following the Schroedinger quantum mechanical approach

    Energy Technology Data Exchange (ETDEWEB)

    Santillan, M [Cinvestav-IPN, Unidad Monterrey, Parque de Investigacion e Innovacion Tecnologica, Autopista Monterrey-Aeropuerto Km 10, 66600 Apodaca NL (Mexico); Zeron, E S [Departamento de Matematicas, Cinvestav-IPN, 07000 Mexico DF (Mexico); Rio-Correa, J L del [Departamento de Fisica, Universidad Autonoma Metropolitana Iztapalapa, 09340 Mexico DF (Mexico)], E-mail: msantillan@cinvestav.mx, E-mail: eszeron@math.cinvestav.mx, E-mail: jlrc@xanum.uam.mx

    2008-05-15

    In the traditional statistical mechanics textbooks, the entropy concept is first introduced for the microcanonical ensemble and then extended to the canonical and grand-canonical cases. However, in the authors' experience, this procedure makes it difficult for the student to see the bigger picture and, although quite ingenuous, the subtleness of the demonstrations to pass from the microcanonical to the canonical and grand-canonical ensembles is hard to grasp. In the present work, we adapt the approach used by Schroedinger to introduce the entropy definition for quantum mechanical systems to derive a classical mechanical entropy definition, which is valid for all ensembles and is in complete agreement with the Gibbs entropy. Afterwards, we show how the specific probability densities for the microcanonical and canonical ensembles can be obtained from the system macrostate, the entropy definition and the second law of thermodynamics. After teaching the approach introduced in this paper for several years, we have found that it allows a better understanding of the statistical mechanics foundations. On the other hand, since it demands previous knowledge of thermodynamics and mathematical analysis, in our experience this approach is more adequate for final-year undergraduate and graduate physics students.

  2. Path Integral Approach to 't Hooft's Derivation of Quantum from Classical Physics

    OpenAIRE

    Blasone, Massimo; Jizba, Petr; Kleinert, Hagen

    2004-01-01

    We present a path-integral formulation of 't Hooft's derivation of quantum from classical physics. The crucial ingredient of this formulation is Gozzi et al.'s supersymmetric path integral of classical mechanics. We quantize explicitly two simple classical systems: the planar mathematical pendulum and the Roessler dynamical system.

  3. Expansion and evaporation of hot nuclei. Comparison between semi-classical and quantal mean-field approaches

    International Nuclear Information System (INIS)

    A general discussion of the mean field dynamics of finite nuclei prepared under extreme conditions of temperature and pressure are presented. The prediction of semi-classical approximation is compared with complete quantum simulations. Many features of the dynamics are carefully studied such as the collective expansion, the evaporation process, the different time-scale... This study points out many quantitative differences between quantum and semi-classical approaches. Part of the differences are related to numerical features inherent in semi-classical simulations but most of them are a direct consequence of the non treatment of nuclei as quantal objects. In particular, it is shown that because of a too strong damping in semi-classical approaches the expansion of hot nuclei is quenched and the speed of the collective motion reduced. (author)

  4. Wigner measures approach to the classical limit of the Nelson model: Convergence of dynamics and ground state energy

    OpenAIRE

    AMMARI, Zied; Falconi, Marco

    2014-01-01

    We consider the classical limit of the Nelson model, a system of stable nucleons interacting with a meson field. We prove convergence of the quantum dynamics towards the evolution of the coupled Klein-Gordon-Schr\\"odinger equation. Also, we show that the ground state energy level of $N$ nucleons, when $N$ is large and the meson field approaches its classical value, is given by the infimum of the classical energy functional at a fixed density of particles. Our study relies on a recently elabor...

  5. Materialism across the life span: An age-period-cohort analysis.

    Science.gov (United States)

    Jaspers, Esther D T; Pieters, Rik G M

    2016-09-01

    This research examined the development of materialism across the life span. Two initial studies revealed that (a) lay beliefs were that materialism declines with age and (b) previous research findings also implied a modest, negative relationship between age and materialism. Yet, previous research has considered age only as a linear control variable, thereby precluding the possibility of more intricate relationships between age and materialism. Moreover, prior studies have relied on cross-sectional data and thus confound age and cohort effects. To improve on this, the main study used longitudinal data from 8 waves spanning 9 years of over 4,200 individuals (16 to 90 years) to examine age effects on materialism while controlling for cohort and period effects. Using a multivariate multilevel latent growth model, it found that materialism followed a curvilinear trajectory across the life span, with the lowest levels at middle age and higher levels before and after that. Thus, in contrast to lay beliefs, materialism increased in older age. Moreover, age effects on materialism differed markedly between 3 core themes of materialism: acquisition centrality, possession-defined success, and acquisition as the pursuit of happiness. In particular, acquisition centrality and possession-defined success were higher at younger and older age. Independent of these age effects, older birth cohorts were oriented more toward possession-defined success, whereas younger birth cohorts were oriented more toward acquisition centrality. The economic downturn since 2008 led to a decrease in acquisition as the pursuit of happiness and in desires for personal growth, but to an increase in desires for achievement. (PsycINFO Database Record PMID:27560768

  6. Age-Period-Cohort Analysis of Female Breast Cancer Mortality in Korea

    OpenAIRE

    Choi, Yunhee; Kim, Yeonju; Park, Sue K.; Shin, Hai-Rim; Yoo, Keun-Young

    2015-01-01

    Purpose Despite the low mortality rate of breast cancer among women in Korea, the breast cancer mortality rate has increased. The aim of this study was to examine trends in breast cancer mortality from 1983 to 2012 in Korea, assessing the importance of age, period, and birth cohort as risk factors. Materials and Methods Data on the annual number of deaths due to female breast cancer and on female population statistics from 1983 to 2012 were obtained from Statistics Korea. A log-linear Poisson...

  7. The Delphi Technique in nursing research - Part 1. The classical methodological approach and its main modifications

    Directory of Open Access Journals (Sweden)

    Dimitrios Theofanidis

    2011-04-01

    Full Text Available The Delphi Technique (DT is a research methodology that uses turns or rounds between the researcher and a group of experts, until a desired level of agreement or consensus between the members of the expert panel has been reached with regards to the question in hand. Despite its popular use in the social sciences' domain and its progressive adoption by nurse-researchers internationally, in Greece, there is a lack of its application; its comprehension, usage, and methodological merits are still in question within the Greek nursing research community. Aim: To provide a detailed presentation of the epistemological and practical value of the DT, through a series of four consecutive papers which expand on the following: i the classical methodological approach and its main modifications, ii the methodological reflections iii analysis and presentation of results, and iv the use and usefulness of the method in application to nursing research. The first of the four papers provides a description and a comparative assessment of the main variations of the DT. Results: A review of the literature elucidated three main sub-types of technique: the Classic or Conventional Delphi, the Policy Delphi and the Decision Delphi Technique. Nevertheless, due to many variations of the basic philosophy of the method and the many differentiations in its application, it is quite difficult to classify each study that used Delphi, with precision. The main methodological differences that can challenge the researcher are discussed and finally, examples that show the advantages and the usefulness of the individual Delphi techniques are given. Conclusions: Use of the DT in research has many advantages and it can become exceptionally useful once the content of the method and its practical applications are fully understood.

  8. Classical convergence versus Zipf rank approach: Evidence from China's local-level data

    Science.gov (United States)

    Tang, Pan; Zhang, Ying; Baaquie, Belal E.; Podobnik, Boris

    2016-02-01

    This paper applies Zipf rank approach to measure how long it will take for the individual economy to reach the final state of equilibrium by using local-level data of China's urban areas. The indicators, the gross domestic product (GDP) per capita and the market capitalization (MCAP) per capita of 150 major cities in China are used for analyzing their convergence. Besides, the power law relationship is examined for GDP and MCAP. Our findings show that, compared to the classical approaches: β-convergence and σ-convergence, the Zipf ranking predicts that, in approximately 16 years, all the major cities in China will reach comparable values of GDP per capita. However, the MCAP per capita tends to follow the periodic fluctuation of the economic cycle, while the mean-log derivation (MLD) confirms the results of our study. Moreover, GDP per capita and MCAP per capita follow a power law with an average value of α = 0.41 which is higher than α = 0.38 obtained based on a large number of countries around the world.

  9. Time-dependent variational approach in terms of squeezed coherent states: Implication to semi-classical approximation

    Science.gov (United States)

    Tsue, Yasuhiko

    1994-01-01

    A general framework for time-dependent variational approach in terms of squeezed coherent states is constructed with the aim of describing quantal systems by means of classical mechanics including higher order quantal effects with the aid of canonicity conditions developed in the time-dependent Hartree-Fock theory. The Maslov phase occurring in a semi-classical quantization rule is investigated in this framework. In the limit of a semi-classical approximation in this approach, it is definitely shown that the Maslov phase has a geometric nature analogous to the Berry phase. It is also indicated that this squeezed coherent state approach is a possible way to go beyond the usual WKB approximation.

  10. Experimental and modeling study of unsaturated solute flow in soils: from classical to discrete approaches

    Science.gov (United States)

    Gerke, K.

    2012-04-01

    Most dye staining experiments in natural soils result in highly heterogeneous flow patterns which are usually explained with presence of preferential flow paths or different kinds of flow instabilities. It is quite logic that soil structure is one of the main factors affecting infiltrations regimes, however the degree of flow stochasticity is not studied enough. In this contribution a substantial amount of large scale (2-4 m lateral excavations) field experiment data is considered (including forested hillslopes and agricultural fields) with special attention to sprinkling of two different staining substances with different dyeing mechanisms (common dye is visible both in adsorbed and in solution states; fluorescent dye - only in solution). The latter method allows an estimation of the flow stability (stochasticity). Most staining field experiments are supported by undisturbed sample collections (laboratory measurements for hydraulic conductivity, water retention curves, X-ray microtomography scans, grain size distributions, etc.). Preliminary results strongly support the evidence of stability of flow under similar precipitation and moisture conditions. Infiltration also correlated with soil structure and microproperties. Numerical modeling using classical approach (single-porosity coupled Richard's and advection-dispersion equations, random hydraulic properties based on log-normal experimentally obtained distribution) fails to describe experimentally obtained staining patterns. Multi-porosity models may provide better tools to account for different soil heterogeneities, but their parameters can not be obtained experimentally. Small scale solutions using pore-network or lattice-Botzmann methods based on microtomography scans are accurate, but computationally expensive (volumes around tens of cm3). Based on field observations a simple cellular automata approach to model staining patterns is developed and tested on experimental data. Our results are much better then

  11. Semi-classical approach of heavy ion physics at intermediate energies

    International Nuclear Information System (INIS)

    The study of heavy ion collisions at intermediate energies (10 to 100 MeV/A), can be undertaken by a semi-classical approach: the nuclear Vlasov equation. It is possible to decompose the one body distribution function over a suitable coherent state basis for dynamical studies. This method is applied for colliding slabs, and the results are compared with those of TDHF. With imposed spherical symmetry, the isoscalar monopole resonance, evaporation, formation of bubble nuclei and total evaporation, are obtained. The extension to three dimensions and to the Landau-Vlasov equation through the residual interaction included in the Uehling-Uhlenbeck collision term, permits a general study of the dynamical instability of highly excited nuclei. The application to heavy ion collisions gives a description of both the main mechanisms of reaction, and the ineffective fusion for the system 40Ar (35 MeV/A) + 27Al. Alpha particle multiplicities in correlation with evaporated residues in the experience 40Ar (27 MeV/A) + 27Al, have been extracted. From theoretical results, different scenari are proposed (entrance channel limitation and exit channel disintegration), in order to explain the disappearance of the fusion component observed for this system at energies above 32 MeV/A

  12. Reading the World's Classics Critically: A Keyword-Based Approach to Literary Analysis in Foreign Language Studies

    Science.gov (United States)

    García, Nuria Alonso; Caplan, Alison

    2014-01-01

    While there are a number of important critical pedagogies being proposed in the field of foreign language study, more attention should be given to providing concrete examples of how to apply these ideas in the classroom. This article offers a new approach to the textual analysis of literary classics through the keyword-based methodology originally…

  13. Simulation of chemical reactions in solution by a combination of classical and quantum mechanical approach

    Science.gov (United States)

    Onida, Giovanni; Andreoni, Wanda

    1995-09-01

    A classical trajectory mapping method was developed to study chemical reactions in solution and in enzymes. In this method, the trajectories were calculated on a classical potential surface and the free energy profile was obtained by mapping the classical surface to the quantum mechanical surface obtained by the semiempirical AM1 method. There is no need to perform expensive quantum mechanical calculations at each iteration step. This method was applied to proton transfer reactions both in aqueous solution and in papain. The results are encouraging, indicating the applicability of this hybrid method to chemical reactions both in solution and in enzymes.

  14. Teaching Statistics Using Classic Psychology Research: An Activities-Based Approach

    Science.gov (United States)

    Holmes, Karen Y.; Dodd, Brett A.

    2012-01-01

    In this article, we discuss a collection of active learning activities derived from classic psychology studies that illustrate the appropriate use of descriptive and inferential statistics. (Contains 2 tables.)

  15. Diversity of approaches to classic galactosemia around the world: a comparison of diagnosis, intervention, and outcomes

    OpenAIRE

    Jumbo-Lucioni, Patricia P.; Garber, Kathryn; Kiel, John; Baric, Ivo; Gerard T. Berry; Bosch, Annet; Burlina, Alberto; Chiesa, Ana; Pico, Maria Luz Couce; Estrada, Sylvia C.; Henderson, Howard; Leslie, Nancy; Longo, Nicola; Morris, Andrew A M; Ramirez-Farias, Carlett

    2012-01-01

    Without intervention, classic galactosemia is a potentially fatal disorder in infancy. With the benefit of early diagnosis and dietary restriction of galactose, the acute sequelae of classic galactosemia can be prevented or reversed. However, despite early and lifelong dietary treatment, many galactosemic patients go on to experience serious long-term complications including cognitive disability, speech problems, neurological and/or movement disorders and, in girls and women, ovarian dysfunct...

  16. Spectral Approach to Chaos and Quantum-Classical Correspondence in Quantum Mapas

    CERN Document Server

    García-Mata, I; Garcia-Mata, Ignacio; Saraceno, Marcos

    2005-01-01

    Correspondence in quantum chaotic systems is lost in short time scales. Introducing some noise we study the spectrum of the resulting coarse grained propagaor of density matrices. Some differen methods to compute the spectrum are reviewed. Moreover, the relationship between the eigenvalues of the coarse-grained superoperator and the classical Ruelle-Pollicott resonances is remarked. As a concequence, classical decay rates in quantum time dependent quantities appear.

  17. A relativistic microscopic approach and a semi-classical approach to high-energy meson-nucleus interactions

    International Nuclear Information System (INIS)

    An optical-potential model originally developed for low-energy (Tπ ≤ 300 MeV) pion-nucleus scattering in momentum space was extended to treat both kaon-nucleus and high-energy pion-nucleus elastic scattering (300 MeV ≤ Tπ ≤ 1 GeV). The optical model utilizes Lorentz covariantly normalized wave functions, full relativistic kinematics and a Klein-Gordon propagator in the Lippmann-Schwinger equation, finite range nucleon form factors plus various nuclear medium corrections. The fermi-averaging integration can be performed exactly. This work on the K+-12C and K+-40Ca elastic differential cross section at a kaon lab momentum of 800 MeV/c confirms a nucleon swelling effect. An enhancement in the two-body amplitude is needed to eliminate the discrepancy between the data and theory. For the high-energy pion-nucleus scattering problem, the optical model approach has been limited to light nuclei (A ≤ 90) and/or at low energy (Tπ ≤ 500 MeV). A simple but effective eikonal approximation for high-energy pion scattering was developed. Both the Coulomb interaction and the semi-classical Wallace corrections are included in the eikonal approximation. The same target wave functions and two-body amplitude are used in both the optical model and the eikonal calculation. Comparison of the results from both calculations shows that the fermi-averaging integration and various sources of non-locality are not important at high energies. The eikonal approximation gives very reliable results, especially for heavy nuclei (A ≥ 28). Predictions utilizing the eikonal approximation are made for elastic differential cross sections of π± on various target nuclei. Contributions from the Coulomb interaction and the Wallace corrections in this energy region are found to be important. Future prospects of studying high-energy pion scattering utilizing the eikonal approximation are discussed

  18. A Unified Approach to the Classical Statistical Analysis of Small Signals

    CERN Document Server

    Feldman, G J; Feldman, Gary J.; Cousins, Robert D.

    1998-01-01

    We give a classical confidence belt construction which unifies the treatment of upper confidence limits for null results and two-sided confidence intervals for non-null results. The unified treatment solves a problem (apparently not previously recognized) that the choice of upper limit or two-sided intervals leads to intervals which are not confidence intervals if the choice is based on the data. We apply the construction to two related problems which have recently been a battle-ground between classical and Bayesian statistics: Poisson processes with background, and Gaussian errors with a bounded physical region. In contrast with the usual classical construction for upper limits, our construction avoids unphysical confidence intervals. In contrast with some popular Bayesian intervals, our intervals eliminate conservatism (frequentist coverage greater than the stated confidence) in the Gaussian case and reduce it to a level dictated by discreteness in the Poisson case. We generalize the method in order to appl...

  19. Modelling of Classical and Rotary Inverted Pendulum Systems - A Generalized Approach

    Science.gov (United States)

    Jadlovský, Slávka; Sarnovský, Ján

    2013-01-01

    The purpose of this paper is to present the design and program implementation of a general procedure which yields the mathematical model for a classical or rotary inverted pendulum system with an arbitrary number of pendulum links. Lagrange equations of the second kind with an integrated Rayleigh dissipation function are employed in model design, and the energetic balance relations, derived for the base and all pendulum links in a generalized (n-link) classical and rotary inverted pendulum system, are implemented in form of symbolic MATLAB functions and a MATLAB GUI application. The validity and accuracy of motion equations generated by the application are demonstrated by evaluating the open-loop responses of simulation models of classical double and rotary single inverted pendulum.

  20. Time-Calibrated Phylogenomics of the Classical Swine Fever Viruses: Genome-Wide Bayesian Coalescent Approach

    OpenAIRE

    Kwon, Taehyung; Yoon, Sook Hee; Kim, Kyu-Won; Caetano-Anolles, Kelsey; Cho, Seoae; Kim, Heebal

    2015-01-01

    The phylogeny of classical swine fever virus (CSFV), the causative agent of classical swine fever (CSF), has been investigated extensively. However, no evolutionary research has been performed using the whole CSFV genome. In this study, we used 37 published genome sequences to investigate the time-calibrated phylogenomics of CSFV. In phylogenomic trees based on Bayesian inference (BI) and Maximum likelihood (ML), the 37 isolates were categorized into five genetic types (1.1, 1.2, 2.1, 2.3, an...

  1. Quantum-classical correspondence of a field induced KAM-type transition: A QTM approach

    Indian Academy of Sciences (India)

    P K Chattaraj; S Sengupta; S Giri

    2008-01-01

    A transition from regular to chaotic behaviour in the dynamics of a classical Henon-Heiles oscillator in the presence of an external field is shown to have a similar quantum signature when studied using the pertaining phase portraits and the associated Kolmogorov-Sinai-Lyapunov entropies obtained through the corresponding Bohmian trajectories.

  2. Geographic Clustering and Productivity: An Instrumental Variable Approach for Classical Composers

    DEFF Research Database (Denmark)

    Borowiecki, Karol

    2013-01-01

    It is difficult to estimate the impact of geographic clustering on productivity because of endogeneity issues. I use birthplace-cluster distance as an instrumental variable for the incidence of clustering of prominent classical composers born between 1750 and 1899. I find that geographic clustering...

  3. Hawking Radiation from a Vaidya Black Hole: A Semi-Classical Approach and Beyond

    CERN Document Server

    Siahaan, Haryanto M

    2008-01-01

    We derive the Hawking radiation for Vaidya black hole in the tunneling picture from the corresponding single particle action by the use of the radial null geodesic and the Hamilton-Jacobi method (beyond semi-classical approximation). Both results are then analyzed and compared.

  4. The Bread and Butter of Classical Organizational Approaches: The Time-and-Motion Study

    Science.gov (United States)

    Peterson, Dan W.

    2007-01-01

    The thought of learning about the principles of classical management and the machine metaphor of organizing can get many organizational communication students yawning just by seeing the subject in a syllabus. Abundant movie and television examples associated with the machine-like nature of workplace productivity are often used to demonstrate…

  5. A Link between Nano- and Classical Thermodynamics: Dissipation Analysis (The Entropy Generation Approach in Nano-Thermodynamics

    Directory of Open Access Journals (Sweden)

    Umberto Lucia

    2015-03-01

    Full Text Available The interest in designing nanosystems is continuously growing. Engineers apply a great number of optimization methods to design macroscopic systems. If these methods could be introduced into the design of small systems, a great improvement in nanotechnologies could be achieved. To do so, however, it is necessary to extend classical thermodynamic analysis to small systems, but irreversibility is also present in small systems, as the Loschmidt paradox highlighted. Here, the use of the recent improvement of the Gouy-Stodola theorem to complex systems (GSGL approach, based on the use of entropy generation, is suggested to obtain the extension of classical thermodynamics to nanothermodynamics. The result is a new approach to nanosystems which avoids the difficulties highlighted in the usual analysis of the small systems, such as the definition of temperature for nanosystems.

  6. Developing a New Integrated Model to improve the using of Classical Approach in Designing Management Information Systems

    OpenAIRE

    Mohammad M M Abu Omar; Khairul Anuar Abdullah

    2015-01-01

    Management information system (MIS) is used to solve management problems in the practical life, the designing and building of the management information systems is done by using one of the systems development methodologies. Classical approach is one of these methodologies which still suffer from some critical problems when it is used in designing and building the management information systems, it consumes more time and cost during its life cycle. This paper develops a new integrated model to...

  7. Projected equations of motion approach to hybrid quantum/classical dynamics in dielectric-metal composites

    CERN Document Server

    McMillan, Ryan J; Grüning, Myrta

    2016-01-01

    We introduce a hybrid method for dielectric-metal composites that describes the dynamics of the metallic system classically whilst retaining a quantum description of the dielectric. The time-dependent dipole moment of the classical system is mimicked by the introduction of projected equations of motion (PEOM) and the coupling between the two systems is achieved through an effective dipole-dipole interaction. To benchmark this method, we model a test system (semiconducting quantum dot-metal nanoparticle hybrid). We begin by examining the energy absorption rate, showing agreement between the PEOM method and the analytical rotating wave approximation (RWA) solution. We then investigate population inversion and show that the PEOM method provides an accurate model for the interaction under ultrashort pulse excitation where the traditional RWA breaks down.

  8. Online solving of economic dispatch problem using neural network approach and comparing it with classical method

    International Nuclear Information System (INIS)

    In this study, two methods for solving economic dispatch problems, namely Hopfield neural network and lambda iteration method are compared. Three sample of power system with 3, 6 and 20 units have been considered. The time required for CPU, for solving economic dispatch of these two systems has been calculated. It has been Shown that for on-line economic dispatch, Hopfield neural network is more efficient and the time required for Convergence is considerably smaller compared to classical methods. (author)

  9. Stabilizability of oscillatory systems: a classical approach supported by symbolic computation

    Directory of Open Access Journals (Sweden)

    Andrea Bacciotti

    1990-11-01

    Full Text Available In this paper we study the stabilization of planar single-input non-linear systems, whose linearization at the origin has purely immaginary eigenvalues. A classical recursive procedure based on polar coordinates transformation is applied to obtain some sufficient conditions. Then we focus on bilinear systems; a complete solution of the problem is given in this case. Explicit statements of the conditions are possible thanks to the use of symbolic computation packages.

  10. Classical r-matrix like approach to Frobenius manifolds, WDVV equations and flat metrics

    International Nuclear Information System (INIS)

    A general scheme for the construction of flat pencils of contravariant metrics and Frobenius manifolds as well as related solutions to Witten–Dijkgraaf–Verlinde–Verlinde associativity equations is formulated. The advantage is taken from the Rota–Baxter identity and some relation being counterpart of the modified Yang–Baxter identity from the classical r-matrix formalism. The scheme for the construction of Frobenius manifolds is illustrated on the algebras of formal Laurent series and meromorphic functions on Riemann sphere. (paper)

  11. A morphing approach to couple state-based peridynamics with classical continuum mechanics

    KAUST Repository

    Han, Fei

    2016-01-04

    A local/nonlocal coupling technique called the morphing method is developed to couple classical continuum mechanics with state-based peridynamics. State-based peridynamics, which enables the description of cracks that appear and propagate spontaneously, is applied to the key domain of a structure, where damage and fracture are considered to have non-negligible effects. In the rest of the structure, classical continuum mechanics is used to reduce computational costs and to simultaneously satisfy solution accuracy and boundary conditions. Both models are glued by the proposed morphing method in the transition region. The morphing method creates a balance between the stiffness tensors of classical continuum mechanics and the weighted coefficients of state-based peridynamics through the equivalent energy density of both models. Linearization of state-based peridynamics is derived by Taylor approximations based on vector operations. The discrete formulation of coupled models is also described. Two-dimensional numerical examples illustrate the validity and accuracy of the proposed technique. It is shown that the morphing method, originally developed for bond-based peridynamics, can be successfully extended to state-based peridynamics through the original developments presented here.

  12. Classical and numerical approaches to determining V-section band clamp axial stiffness

    Science.gov (United States)

    Barrans, Simon M.; Khodabakhshi, Goodarz; Muller, Matthias

    2014-12-01

    V-band clamp joints are used in a wide range of applications to connect circular flanges, for ducts, pipes and the turbocharger housing. Previous studies and research on V-bands are either purely empirical or analytical with limited applicability on the variety of V-band design and working conditions. In this paper models of the V-band are developed based on the classical theory of solid mechanics and the finite element method to study the behaviour of theV-bands under axial loading conditions. The good agreement between results from the developed FEA and the classical model support the suitability of the latter to modelV-band joints with diameters greater than 110mm under axial loading. The results from both models suggest that the axial stiffness for thisV-band cross section reaches a peak value for V-bands with radius of approximately 150 mmacross a wide range of coefficients of friction. Also, it is shown that the coefficient of friction and the wedge angle have a significant effect on the axial stiffness of V-bands.

  13. An Approach to Some Non-Classical Eigenvalue Problems of Structural Dynamics

    Directory of Open Access Journals (Sweden)

    Sandi Horea

    2015-12-01

    Full Text Available Two main shortcomings of common formulations, encountered in the literature concerning the linear problems of structural dynamics are revealed: the implicit, not discussed, postulation, of the use of Kelvin – Voigt constitutive laws (which is often infirmed by experience and the calculation difficulties involved by the attempts to use other constitutive laws. In order to overcome these two categories of shortcomings, the use of the bilateral Laplace – Carson transformation is adopted. Instead of the dependence on time, t, of a certain function f (t, the dependence of its image f# (p on the complex parameter p = χ + iω (ω: circular frequency will occur. This leads to the formulation of associated non-classical eigenvalue problems. The basic relations satisfied by the eigenvalues λr#(p and the eigenvectors vr#(p of dynamic systems are examined (among other, the property of orthogonality of eigenvectors is replaced by the property of pseudo-orthogonality. The case of points p = p’, where multiple eigenvalues occur and where, as a rule, chains of principal vectors are to be considered, is discussed. An illustrative case, concerning a non-classical eigenvalue problem, is presented. Plots of variation along the ω axis, for the real and imaginary components of eigenvalues and eigenvectors, are presented. A brief final discussion closes the paper.

  14. A New Approach to the Classical and Quantum Dynamics of Branes

    CERN Document Server

    Pavšič, Matej

    2016-01-01

    It is shown that the Dirac-nambu-Goto brane can be described as a point particle in an infinite dimensional brane space with a particular metric. This suggests a generalization to brane spaces with arbitrary metric, including the "flat" metric. Then quantization of such a system is straightforward: it is just like quantization of a bunch of non interacting particles. This leads us to a system of a continuous set of scalar fields. For a particular choice of the metric in the space of fields we find that the classical Dirac-Nambu-Goto brane theory arises as an effective theory of such an underlying quantum field theory. Quantization of branes is important for the brane world scenarios, and thus for "quantum gravity".

  15. A new approach to the classical and quantum dynamics of branes

    Science.gov (United States)

    Pavšič, Matej

    2016-07-01

    It is shown that the Dirac-Nambu-Goto brane can be described as a point particle in an infinite-dimensional brane space with a particular metric. This suggests a generalization to brane spaces with arbitrary metric, including the “flat” metric. Then quantization of such a system is straightforward: it is just like quantization of a bunch of noninteracting particles. This leads us to a system of a continuous set of scalar fields. For a particular choice of the metric in the space of fields we find that the classical Dirac-Nambu-Goto brane theory arises as an effective theory of such an underlying quantum field theory. Quantization of branes is important for the brane world scenarios, and thus for “quantum gravity.”

  16. Chandrasekhar limit: an elementary approach based on classical physics and quantum theory

    Science.gov (United States)

    Pinochet, Jorge; Van Sint Jan, Michael

    2016-05-01

    In a brief article published in 1931, Subrahmanyan Chandrasekhar made public an important astronomical discovery. In his article, the then young Indian astrophysicist introduced what is now known as the Chandrasekhar limit. This limit establishes the maximum mass of a stellar remnant beyond which the repulsion force between electrons due to the exclusion principle can no longer stop the gravitational collapse. In the present article, we create an elemental approximation to the Chandrasekhar limit, accessible to non-graduate science and engineering students. The article focuses especially on clarifying the origins of Chandrasekhar’s discovery and the underlying physical concepts. Throughout the article, only basic algebra is used as well as some general notions of classical physics and quantum theory.

  17. A new approach in classical electrodynamics to protect principle of causality

    Directory of Open Access Journals (Sweden)

    Biswaranjan Dikshit

    2014-03-01

    Full Text Available In classical electrodynamics, electromagnetic effects are calculated from solution of wave equation formed by combination of four Maxwell’s equations. However, along with retarded solution, this wave equation admits advanced solution in which case the effect happens before the cause. So, to preserve causality in natural events, the retarded solution is intentionally chosen and the advance part is just ignored. But, an equation or method cannot be called fundamental if it admits a wrong result (that violates principle of causality in addition to the correct result. Since it is the Maxwell’s form of equations that gives birth to this acausal advanced potential, we rewrite these equations in a different form using the recent theory of reaction at a distance (Biswaranjan Dikshit, Physics essays, 24(1, 4-9, 2011 so that the process of calculation does not generate any advanced effects. Thus, the long-standing causality problem in electrodynamics is solved.

  18. Mass and Heat Diffusion in Ternary Polymer Solutions: A Classical Irreversible Thermodynamics Approach

    CERN Document Server

    Es-haghi, S Shams

    2016-01-01

    Governing equations for evolution of concentration and temperature in three-component systems were derived in the framework of classical irreversible thermodynamics using Onsager variational principle and were presented for solvent/solvent/polymer and solvent/polymer/polymer systems. The derivation was developed from the Gibbs equation of equilibrium thermodynamics using the local equilibrium hypothesis, Onsager reciprocal relations and Prigogine theorem for systems in mechanical equilibrium. It was shown that the details of mass and heat diffusion phenomena in a ternary system are completely expressed by a 3x3 matrix whose entries are mass diffusion coefficients (4 entries), thermal diffusion coefficients (2 entries) and three entries that describe the evolution of heat in the system. The entries of the diffusion matrix are related to the elements of Onsager matrix that are bounded by some constraints to satisfy the positive definiteness of entropy production in the system. All the elements of diffusion matr...

  19. A Clifford Algebra Approach to the Classical Problem of a Charge in a Magnetic Monopole Field

    Science.gov (United States)

    Vaz, Jayme

    2013-05-01

    The motion of an electric charge in the field of a magnetic monopole is described by means of a Lagrangian model written in terms of the Clifford algebra of the physical space. The equations of motion are written in terms of a radial equation (involving r=| r|, where r( t) is the charge trajectory) and a rotor equation (written in terms of an unitary operator spinor R). The solution corresponding to the charge trajectory in the field of a magnetic monopole is given in parametric form. The model can be generalized in order to describe the motion of a charge in the field of a magnetic monopole and other additional central forces, and as an example, we discuss the classical ones involving linear and inverse square interactions.

  20. Adler-Gelfand-Dickey approach to classical W-algebras within the theory of Poisson vertex algebras

    OpenAIRE

    Sole, A.; Kac, V. G.; Valeri, D.

    2014-01-01

    We put the Adler-Gelfand-Dickey approach to classical W-algebras in the framework of Poisson vertex algebras. We show how to recover the bi-Poisson structure of the KP hierarchy, together with its generalizations and reduction to the N-th KdV hierarchy, using the formal distribution calculus and the lambda-bracket formalism. We apply the Lenard-Magri scheme to prove integrability of the corresponding hierarchies. We also give a simple proof of a theorem of Kupershmidt and Wilson in this frame...

  1. Social History of Medicine today – a classic approach beyond the turns of the turns

    Directory of Open Access Journals (Sweden)

    Alfons Labisch

    2015-06-01

    Full Text Available In the late 1960s, social history developed into an imperative approach in general historiography in Germany. Since the mid‐1970s, also social history of medicine has been developed into a comprehensive research approach. But in the 1990s, all of a sudden, social history of medicine vanished. The constructivist history of science, the linguistic‐ constructivist theories in humanities and micro‐historiographical approaches from general history prevailed. After the firstdecade of the 21st century, the innovative highlights of these developments exceeded. Just at this point, it is appropriate to ask for the genuine and permanent role of a social history of medicine. Seen from the peculiarity of medicine the social history of medicine has a genuine field of topics in the social environment of disease and health. These topics have to be treated with their own approaches and methods, derived from its reference disciplines sociology and economics.

  2. A hybrid classical-quantum approach for ultra-scaled confined nanostructures : modeling and simulation*

    Directory of Open Access Journals (Sweden)

    Pietra Paola

    2012-04-01

    Full Text Available We propose a hybrid classical-quantum model to study the motion of electrons in ultra-scaled confined nanostructures. The transport of charged particles, considered as one dimensional, is described by a quantum effective mass model in the active zone coupled directly to a drift-diffusion problem in the rest of the device. We explain how this hybrid model takes into account the peculiarities due to the strong confinement and we present numerical simulations for a simplified carbon nanotube. Nous proposons un modèle hybride classique-quantique pour décrire le mouvement des électrons dans des nanostructures très fortement confinées. Le transport des particules, consideré unidimensionel, est décrit par un modèle quantique avec masse effective dans la zone active couplé à un problème de dérive-diffusion dans le reste du domaine. Nous expliquons comment ce modèle hybride prend en compte les spécificités de ce très fort confinement et nous présentons des résultats numériques pour un nanotube de carbone simplifié.

  3. Infinite-dimensional Lie algebras, classical r-matrices, and Lax operators: Two approaches

    Science.gov (United States)

    Skrypnyk, T.

    2013-10-01

    For each finite-dimensional simple Lie algebra {g}, starting from a general {g}⊗ {g}-valued solutions r(u, v) of the generalized classical Yang-Baxter equation, we construct infinite-dimensional Lie algebras widetilde{{g}}-_r of {g}-valued meromorphic functions. We outline two ways of embedding of the Lie algebra widetilde{{g}}-_r into a larger Lie algebra with Kostant-Adler-Symmes decomposition. The first of them is an embedding of widetilde{{g}}-_r into Lie algebra widetilde{{g}}(u^{-1},u)) of formal Laurent power series. The second is an embedding of widetilde{{g}}-_r as a quasigraded Lie subalgebra into a quasigraded Lie algebra widetilde{{g}}_r: widetilde{{g}}_r=widetilde{{g}}-_r+widetilde{{g}}+_r, such that the Kostant-Adler-Symmes decomposition is consistent with a chosen quasigrading. We construct dual spaces widetilde{{g}}^*_r, (widetilde{{g}}^{± }_r)^* and explicit form of the Lax operators L(u), L±(u) as elements of these spaces. We develop a theory of integrable finite-dimensional hamiltonian systems and soliton hierarchies based on Lie algebras widetilde{{g}}_r, widetilde{{g}}^{± }_r. We consider examples of such systems and soliton equations and obtain the most general form of integrable tops, Kirchhoff-type integrable systems, and integrable Landau-Lifshitz-type equations corresponding to the Lie algebra {g}.

  4. Vibrationally enhanced associative photodesorption of H2 (D2) from Ru(0001). Quantum and classical approaches

    International Nuclear Information System (INIS)

    This thesis investigates the femtosecond laser induced associative photodesorption of hydrogen, H2, and deuterium, D2, from a ruthenium metal surface. One of the goals of the present thesis is to suggest, on the basis of theoretical simulations, strategies to control/enhance the photodesorption yield from Ru(0001). For this purpose, we suggest a hybrid scheme to control the reaction, where the adsorbate vibrations are initially excited by an infrared (IR) pulse, prior to the vis pulse. Both adiabatic and non-adiabatic representations for photoinduced desorption problems are employed here. The adiabatic representation is realized within the classical picture using Molecular Dynamics (MD) with electronic frictions. In a quantum mechanical description, non-adiabatic representations are employed within open-system density matrix theory. The time evolution of the desorption process is studied using a two-mode reduced dimensionality model with one vibrational coordinate and one translational coordinate of the adsorbate. The ground and excited electronic state potentials, and dipole function for the IR excitation are taken from first principles. The IR driven vibrational excitation of adsorbate modes with moderate efficiency is achieved by (modified) π-pulses or/and optimal control theory. The fluence dependence of the desorption reaction is computed by including the electronic temperature of the metal calculated from the two-temperature model. We then employed the IR+vis strategy in both models. Here, we found that vibrational excitation indeed promotes the desorption of hydrogen and deuterium. (orig.)

  5. A Markov Chain Approach for Defining the Fundamental Efficiency Limits of Classical and Bifacial Multi-junction Tandem Solar Cells

    CERN Document Server

    Alam, Muhammad A

    2016-01-01

    Bifacial tandem cells promise to reduce three fundamental losses (above-bandgap, below bandgap, and the uncollected light between panels) inherent in classical single junction PV systems. The successive filtering of light through the bandgap cascade, and requirement of current continuity make optimization of tandem cells difficult, accessible only to numerical solution through computer modeling. The challenge is even more complicated for bifacial design. In this paper, we use an elegantly simple Markov chain approach to show that the essential physics of optimization is intuitively obvious, and deeply insightful results can obtained analytically with a few lines of algebra. This powerful approach reproduces, as special cases, all the known results of traditional/bifacial tandem cells, and highlights the asymptotic efficiency gain of these technologies.

  6. Combining classical and molecular approaches elaborates on the complexity of mechanisms underpinning anterior regeneration.

    Science.gov (United States)

    Evans, Deborah J; Owlarn, Suthira; Tejada Romero, Belen; Chen, Chen; Aboobaker, A Aziz

    2011-01-01

    The current model of planarian anterior regeneration evokes the establishment of low levels of Wnt signalling at anterior wounds, promoting anterior polarity and subsequent elaboration of anterior fate through the action of the TALE class homeodomain PREP. The classical observation that decapitations positioned anteriorly will regenerate heads more rapidly than posteriorly positioned decapitations was among the first to lead to the proposal of gradients along an anteroposterior (AP) axis in a developmental context. An explicit understanding of this phenomenon is not included in the current model of anterior regeneration. This raises the question what the underlying molecular and cellular basis of this temporal gradient is, whether it can be explained by current models and whether understanding the gradient will shed light on regenerative events. Differences in anterior regeneration rate are established very early after amputation and this gradient is dependent on the activity of Hedgehog (Hh) signalling. Animals induced to produce two tails by either Smed-APC-1(RNAi) or Smed-ptc(RNAi) lose anterior fate but form previously described ectopic anterior brain structures. Later these animals form peri-pharyngeal brain structures, which in Smed-ptc(RNAi) grow out of the body establishing a new A/P axis. Combining double amputation and hydroxyurea treatment with RNAi experiments indicates that early ectopic brain structures are formed by uncommitted stem cells that have progressed through S-phase of the cell cycle at the time of amputation. Our results elaborate on the current simplistic model of both AP axis and brain regeneration. We find evidence of a gradient of hedgehog signalling that promotes posterior fate and temporarily inhibits anterior regeneration. Our data supports a model for anterior brain regeneration with distinct early and later phases of regeneration. Together these insights start to delineate the interplay between discrete existing, new, and then

  7. Combining classical and molecular approaches elaborates on the complexity of mechanisms underpinning anterior regeneration.

    Directory of Open Access Journals (Sweden)

    Deborah J Evans

    Full Text Available The current model of planarian anterior regeneration evokes the establishment of low levels of Wnt signalling at anterior wounds, promoting anterior polarity and subsequent elaboration of anterior fate through the action of the TALE class homeodomain PREP. The classical observation that decapitations positioned anteriorly will regenerate heads more rapidly than posteriorly positioned decapitations was among the first to lead to the proposal of gradients along an anteroposterior (AP axis in a developmental context. An explicit understanding of this phenomenon is not included in the current model of anterior regeneration. This raises the question what the underlying molecular and cellular basis of this temporal gradient is, whether it can be explained by current models and whether understanding the gradient will shed light on regenerative events. Differences in anterior regeneration rate are established very early after amputation and this gradient is dependent on the activity of Hedgehog (Hh signalling. Animals induced to produce two tails by either Smed-APC-1(RNAi or Smed-ptc(RNAi lose anterior fate but form previously described ectopic anterior brain structures. Later these animals form peri-pharyngeal brain structures, which in Smed-ptc(RNAi grow out of the body establishing a new A/P axis. Combining double amputation and hydroxyurea treatment with RNAi experiments indicates that early ectopic brain structures are formed by uncommitted stem cells that have progressed through S-phase of the cell cycle at the time of amputation. Our results elaborate on the current simplistic model of both AP axis and brain regeneration. We find evidence of a gradient of hedgehog signalling that promotes posterior fate and temporarily inhibits anterior regeneration. Our data supports a model for anterior brain regeneration with distinct early and later phases of regeneration. Together these insights start to delineate the interplay between discrete existing, new

  8. A Classical Fuzzy Approach for Software Effort Estimation on Machine Learning Technique

    CERN Document Server

    Malathi, S

    2011-01-01

    Software Cost Estimation with resounding reliability,productivity and development effort is a challenging and onerous task. This has incited the software community to give much needed thrust and delve into extensive research in software effort estimation for evolving sophisticated methods. Estimation by analogy is one of the expedient techniques in software effort estimation field. However, the methodology utilized for the estimation of software effort by analogy is not able to handle the categorical data in an explicit and precise manner. A new approach has been developed in this paper to estimate software effort for projects represented by categorical or numerical data using reasoning by analogy and fuzzy approach. The existing historical data sets, analyzed with fuzzy logic, produce accurate results in comparison to the data set analyzed with the earlier methodologies.

  9. Physical theatre as an approach to contemporary stagings of classical Greek tragedy

    OpenAIRE

    Moschochoriti, Rubini

    2009-01-01

    This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University. This PhD focuses on physical theatre techniques and practices in order to provide acting keys for directing ancient drama. More specifically, the work for stage put effort in the acting method, with which the chorus and the main characters can be approached. For that reason, the basic method adopted was that of J. Lecoq, and especially the ‘transference’ practice. Moreover, specific elemen...

  10. A Neo-Classical Supply-Based Approach to Land Prices

    OpenAIRE

    Barrie Needham

    1981-01-01

    Current interest in land-price theory is dominated by attempts to explain the structure of land prices and land uses in urban areas. Those theories, however, do not enable certain important political issues to be elucidated, in particular the relationship between produce price and land price. A different approach is therefore suggested, which considers the supply of land to consist of a supply of stocks of land differentiated by fertility, location, etc., the production function for an indust...

  11. Dynamical coupling of plasmons and molecular excitations by hybrid quantum/classical calculations: time-domain approach

    International Nuclear Information System (INIS)

    The presence of plasmonic material influences the optical properties of nearby molecules in untrivial ways due to the dynamical plasmon-molecule coupling. We combine quantum and classical calculation schemes to study this phenomenon in a hybrid system that consists of a Na2 molecule located in the gap between two Au/Ag nanoparticles. The molecule is treated quantum-mechanically with time-dependent density-functional theory, and the nanoparticles with quasistatic classical electrodynamics. The nanoparticle dimer has a plasmon resonance in the visible part of the electromagnetic spectrum, and the Na2 molecule has an electron-hole excitation in the same energy range. Due to the dynamical interaction of the two subsystems the plasmon and the molecular excitations couple, creating a hybridized molecular-plasmon excited state. This state has unique properties that yield e.g. enhanced photoabsorption compared to the freestanding Na2 molecule. The computational approach used enables decoupling of the mutual plasmon-molecule interaction, and our analysis verifies that it is not legitimate to neglect the backcoupling effect when describing the dynamical interaction between plasmonic material and nearby molecules. Time-resolved analysis shows nearly instantaneous formation of the coupled state, and provides an intuitive picture of the underlying physics. (paper)

  12. Dynamical coupling of plasmons and molecular excitations by hybrid quantum/classical calculations: time-domain approach

    Science.gov (United States)

    Sakko, Arto; Rossi, Tuomas P.; Nieminen, Risto M.

    2014-08-01

    The presence of plasmonic material influences the optical properties of nearby molecules in untrivial ways due to the dynamical plasmon-molecule coupling. We combine quantum and classical calculation schemes to study this phenomenon in a hybrid system that consists of a Na2 molecule located in the gap between two Au/Ag nanoparticles. The molecule is treated quantum-mechanically with time-dependent density-functional theory, and the nanoparticles with quasistatic classical electrodynamics. The nanoparticle dimer has a plasmon resonance in the visible part of the electromagnetic spectrum, and the Na2 molecule has an electron-hole excitation in the same energy range. Due to the dynamical interaction of the two subsystems the plasmon and the molecular excitations couple, creating a hybridized molecular-plasmon excited state. This state has unique properties that yield e.g. enhanced photoabsorption compared to the freestanding Na2 molecule. The computational approach used enables decoupling of the mutual plasmon-molecule interaction, and our analysis verifies that it is not legitimate to neglect the backcoupling effect when describing the dynamical interaction between plasmonic material and nearby molecules. Time-resolved analysis shows nearly instantaneous formation of the coupled state, and provides an intuitive picture of the underlying physics.

  13. Standard error in the Jacobson and Truax Reliable Change Index: the "classical approach" leads to poor estimates.

    Science.gov (United States)

    Temkin, Nancy R

    2004-10-01

    Different authors have used different estimates of variability in the denominator of the Reliable Change Index (RCI). Maassen attempts to clarify some of the differences and the assumptions underlying them. In particular he compares the 'classical' approach using an estimate S(Ed) supposedly based on measurement error alone with an estimate S(Diff) based on the variability of observed differences in a population that should have no true change. Maassen concludes that not only is S(Ed) based on classical theory, but it properly estimates variability due to measurement error and practice effect while S(Diff) overestimates variability by accounting twice for the variability due to practice. Simulations show Maassen to be wrong on both accounts. With an error rate nominally set to 10%, RCI estimates using S(Diff) wrongly declare change in 10.4% and 9.4% of simulated cases without true change while estimates using S(Ed) wrongly declare change in 17.5% and 12.3% of the simulated cases (p practice effects, SEd estimates the variability of change due to measurement error to be .34, when the true variability due to measurement error was .014. Neuropsychologists should not use SEd in the denominator of the RCI. PMID:15637781

  14. New Bounds for Old Algorithms: On the Average-Case Behavior of Classic Single-Source Shortest-Paths Approaches

    Science.gov (United States)

    Meyer, Ulrich; Negoescu, Andrei; Weichert, Volker

    Despite disillusioning worst-case behavior, classic algorithms for single-source shortest-paths (SSSP) like Bellman-Ford are still being used in practice, especially due to their simple data structures. However, surprisingly little is known about the average-case complexity of these approaches. We provide new theoretical and experimental results for the performance of classic label-correcting SSSP algorithms on graph classes with non-negative random edge weights. In particular, we prove a tight lower bound of Ω(n 2) for the running times of Bellman-Ford on a class of sparse graphs with O(n) nodes and edges; the best previous bound was Ω(n 4/3 - ɛ ). The same improvements are shown for Pallottino's algorithm. We also lift a lower bound for the approximate bucket implementation of Dijkstra's algorithm from Ω(n logn / loglogn) to Ω(n 1.2 - ɛ ). Furthermore, we provide an experimental evaluation of our new graph classes in comparison with previously used test inputs.

  15. A semi-classical approach for solving the time-dependent Schrödinger equation in inhomogeneous electromagnetic fields

    Science.gov (United States)

    Li, Jianxiong; Thumm, Uwe

    2016-05-01

    During the IR-streaked XUV photoemission from nanoparticles, the net IR electric field varies over the spatial extension of the target, an effect that for metallic particles is further enhanced by strong induced plasmonic polarization. This spatial dependence prevents the convenient use of ``Volkov states'' [solutions of the time-dependent Schrödinger equation for a free electron in a spatially homogeneous (cw) electromagnetic field] as approximate final states in quantum-mechanical photoemission calculations. To obtain the wave function of a free electron in a spatially inhomogeneous electromagnetic field, we propose a semi-classical approach based on time-dependent WKB theory. Generalizing ordinary Volkov states, this method provides a simple expression for modeling the final photoelectron state. We employ such generalized Volkov states to calculate the streaked photoelectron spectra from gold nanospheres and assess their accurary. Supported by the NSD-EPSCoR program, NSF, and the USDoE.

  16. Design of multifunctional compounds for cardiovascular disease: from natural scaffolds to "classical" multitarget approach.

    Science.gov (United States)

    Bisi, A; Gobbi, S; Belluti, F; Rampa, A

    2013-01-01

    Cardiovascular disease represents the main cause of death worldwide. Novel therapies to reduce elevated blood pressure and treat resistant hypertension, to consequently reduce the associated cardiovascular risk factors, are still required. Among the different strategies commonly used in medicinal chemistry to develop new molecules, the synthesis of multitarget/hybrid compounds combining two or more pharmacophore groups targeting simultaneously selected factors involved in cardiovascular diseases, has gained increasing interest. This review will focus on the most recent literature on multifunctional cardiovascular drugs, paying particular attention on hybrid compounds bearing natural scaffolds, considering that compounds derived from medicinal extracts are generally appealing for the medicinal chemist as they often bear the so-called "privileged structures". Moreover, taking into account many excellent reviews dealing with multitarget cardiovascular drugs published in the last few years, mainly devoted to RAAS inhibition and/or NO donors hybrid drugs, herein the most significant results obtained and the benefits and limitations of these approaches will be highlighted. PMID:23410171

  17. Correlated nuclear and electronic dynamics in photoionized systems studied by quantum and mixed quantum-classical approaches

    International Nuclear Information System (INIS)

    The advent of free electron lasers and high harmonic sources enables the investigation of electronic and nuclear dynamics of molecules and solids with atomic spatial resolution and femtosecond/attosecond time resolution, using bright and ultrashort laser pulses of frequency from terahertz to hard x-ray range. With the help of ultrashort laser pulses, the nuclear and electronic dynamics can be initiated, monitored and actively controlled at the typical time scale in the femtosecond to attosecond realm. Meanwhile, theoretical tools are required to describe the underlying mechanism. This doctoral thesis focuses on the development of theoretical tools based on full quantum mechanical multiconfiguration time-dependent Hartree (MCTDH) and mixed quantum classical approaches, which can be applied to describe the dynamical behavior of gas phase molecules and strongly correlated solids in the presence of ultrashort laser pulses. In the first part of this thesis, the focus is on the motion of electron holes in gas phase molecular ions created by extreme ultraviolet (XUV) photoionization and watched by spectroscopic approaches. The XUV photons create electron-hole in the valence orbitals of molecules by photoionization, the electron hole, as a positively charged quasi-particle, can then interact with the nuclei and the rest of electrons, leading to coupled non-Born-Oppenheimer dynamics. I present our study on electron-hole relaxation dynamics in valence ionized molecular ions of moderate size, using quantum wave packet and mixed quantum-classical approaches, using photoionized [H+(H2O)n]+ molecular ion as example. We have shown that the coupled motion of the electron-hole and the nuclei can be mapped out with femtosecond resolution by core-level x-ray transient absorption spectroscopy. Furthermore, in specific cases, the XUV photon can create a coherent electron hole, that can maintain its coherence to time scales of ∝ 1 picosecond. Employing XUV pump - IR probe spectroscopy

  18. An Approach to Source Code Conversion of Classical Programming Languages into Source Code of Quantum Programming Languages

    OpenAIRE

    Bojić, Alan

    2014-01-01

    Basic principles of quantum computer ensure more computing power than the principles of classical computers. Quantum computers use quantum mechanical effects such as entanglement and superposition to speed up computing processes compared to classical computers. If the quantum computers one day becomes a commercially available product, then it is very important to have a converter that will convert the source code of programming languages for classical computers into source code of programming...

  19. Classical antiparticles

    Energy Technology Data Exchange (ETDEWEB)

    Costella, J.P.; McKellar, B.H.J.; Rawlinson, A.A.

    1997-03-01

    We review how antiparticles may be introduced in classical relativistic mechanics, and emphasize that many of their paradoxical properties can be more transparently understood in the classical than in the quantum domain. (authors). 13 refs., 1 tab.

  20. How does socioeconomic development affect COPD mortality? An age-period-cohort analysis from a recently transitioned population in China.

    Directory of Open Access Journals (Sweden)

    Jing Chen

    Full Text Available BACKGROUND: Chronic obstructive pulmonary disease (COPD is a leading cause of death, particularly in developing countries. Little is known about the effects of economic development on COPD mortality, although economic development may potentially have positive and negative influences over the life course on COPD. We took advantage of a unique population whose rapid and recent economic development is marked by changes at clearly delineated and identifiable time points, and where few women smoke, to examine the effect of macro-level events on COPD mortality. METHODS: We used Poisson regression to decompose sex-specific COPD mortality rates in Hong Kong from 1981 to 2005 into the effects of age, period and cohort. RESULTS: COPD mortality declined strongly over generations for people born from the early to mid 20th century, which was particularly evident for the first generation to grow up in a more economically developed environment for both sexes. Population wide COPD mortality decreased when air quality improved and increased with increasing air pollution. COPD mortality increased with age, particularly after menopause among women. CONCLUSIONS: Economic development may reduce vulnerability to COPD by reducing long-lasting insults to the respiratory system, such as infections, poor nutrition and indoor air pollution. However, some of these gains may be offset if economic development results in increasing air pollution or increasing smoking.

  1. Classical Latent Profile Analysis of Academic Self-Concept Dimensions: Synergy of Person- and Variable-Centered Approaches to Theoretical Models of Self-Concept

    Science.gov (United States)

    Marsh, Herbert W.; Ludtke, Oliver; Trautwein, Ulrich; Morin, Alexandre J. S.

    2009-01-01

    In this investigation, we used a classic latent profile analysis (LPA), a person-centered approach, to identify groups of students who had similar profiles for multiple dimensions of academic self-concept (ASC) and related these LPA groups to a diverse set of correlates. Consistent with a priori predictions, we identified 5 LPA groups representing…

  2. The Ancient Greeks Speak to Us: A New Humanistic Approach to Classical Greek and Greek Culture for Secondary Schools. Teacher's Guide-Level Alpha.

    Science.gov (United States)

    Masciantonio, Rudolph; And Others

    A humanistic approach to the study of classical Greek and Greek culture at the secondary school level is detailed in this guide. References to the student programed text and other multisensory instructional materials used in the system focus on instructional objectives geared to students who are not necessarily college-bound. The standard Attic…

  3. A criticism to the classical technology innovation approach. A case study of greenhouse use in the Horticultural Belt of La Plata

    Directory of Open Access Journals (Sweden)

    Matías García

    2014-06-01

    Full Text Available This aim of this work is to critically analyze the classical technology adoption-diffusion approach. In order to do this, a general study of Rogers’s technology adoption approach is first performed. A case study is then carried out in which we describe and analyze the onset and expansion of the most important horticultural sector’s innovation: the use of greenhouse technology in the area of La Plata. Together with these two sections, we discuss how pertinent this innovation approach is and we show that Rogers’s model fails to explain small horticulturists’ behavior in the face of this technological landmark. Finally, a novel perspective is presented which may very well supplement this classical approach.

  4. Classical integrability

    Science.gov (United States)

    Torrielli, Alessandro

    2016-08-01

    We review some essential aspects of classically integrable systems. The detailed outline of the sections consists of: 1. Introduction and motivation, with historical remarks; 2. Liouville theorem and action-angle variables, with examples (harmonic oscillator, Kepler problem); 3. Algebraic tools: Lax pairs, monodromy and transfer matrices, classical r-matrices and exchange relations, non-ultralocal Poisson brackets, with examples (non-linear Schrödinger model, principal chiral field); 4. Features of classical r-matrices: Belavin–Drinfeld theorems, analyticity properties, and lift of the classical structures to quantum groups; 5. Classical inverse scattering method to solve integrable differential equations: soliton solutions, spectral properties and the Gel’fand–Levitan–Marchenko equation, with examples (KdV equation, Sine-Gordon model). Prepared for the Durham Young Researchers Integrability School, organised by the GATIS network. This is part of a collection of lecture notes.

  5. A broadened classical master equation approach for nonadiabatic dynamics at metal surfaces: Beyond the weak molecule-metal coupling limit.

    Science.gov (United States)

    Dou, Wenjie; Subotnik, Joseph E

    2016-01-14

    A broadened classical master equation (BCME) is proposed for modeling nonadiabatic dynamics for molecules near metal surfaces over a wide range of parameter values and with arbitrary initial conditions. Compared with a standard classical master equation-which is valid in the limit of weak molecule-metal couplings-this BCME should be valid for both weak and strong molecule-metal couplings. (The BCME can be mapped to a Fokker-Planck equation that captures level broadening correctly.) Finally, our BCME can be solved with a simple surface hopping algorithm; numerical tests of equilibrium and dynamical observables look very promising. PMID:26772563

  6. Kendall's Shape Statistics as a Classical Realization of Barbour-type Timeless Records Theory approach to Quantum Gravity

    CERN Document Server

    Anderson, Edward

    2013-01-01

    I already showed that Kendall's shape geometry work was the geometrical description of Barbour's relational mechanics' reduced configuration spaces (alias shape spaces). I now describe the extent to which Kendall's subsequent statistical application to such as the `standing stones problem' realizes further ideas along the lines of Barbour-type timeless records theories, albeit just at the classical level.

  7. Kendall's Shape Statistics as a Classical Realization of Barbour-type Timeless Records Theory approach to Quantum Gravity

    OpenAIRE

    Anderson, Edward

    2013-01-01

    I previously showed that Kendall's work on shape geometry is in fact also the geometrical description of Barbour's relational mechanics' reduced configuration spaces (alias shape spaces). I now describe the extent to which Kendall's subsequent statistical application to e.g. the `standing stones problem' realizes further ideas along the lines of Barbour-type timeless records theories, albeit just at the classical level.

  8. Classical Tunneling

    CERN Document Server

    Cohn, A G; Rabinowitz, Mario

    2003-01-01

    A classical representation of an extended body over barriers of height greater than the energy of the incident body is shown to have many features in common with quantum tunneling as the center-of-mass literally goes through the barrier. It is even classically possible to penetrate any finite barrier with a body of arbitrarily low energy if the body is sufficiently long. A distribution of body lengths around the de Broglie wavelength leads to reasonable agreement with the quantum transmission coefficient.

  9. Classical Tunneling

    OpenAIRE

    Cohn, Arthur; Rabinowitz, Mario

    2003-01-01

    A classical representation of an extended body over barriers of height greater than the energy of the incident body is shown to have many features in common with quantum tunneling as the center-of-mass literally goes through the barrier. It is even classically possible to penetrate any finite barrier with a body of arbitrarily low energy if the body is sufficiently long. A distribution of body lengths around the de Broglie wavelength leads to reasonable agreement with the quantum transmission...

  10. Classical Motion

    OpenAIRE

    Mould, Richard A

    2003-01-01

    Preciously given rules allow conscious systems to be included in quantum mechanical systems. There rules are derived from the empirical experience of an observer who witnesses a quantum mechanical interaction leading to the capture of a single particle. In the present paper it is shown that purely classical changes experienced by an observer are consistent with these rules. Three different interactions are considered, two of which combine classical and quantum mechanical changes. The previous...

  11. A Simple Approach to Distinguish Classic and Formaldehyde-Free Tannin Based Rigid Foams by ATR FT-IR

    Directory of Open Access Journals (Sweden)

    Gianluca Tondi

    2015-01-01

    Full Text Available Tannin based rigid foams (TBRFs have been produced with formaldehyde since 1994. Only recently several methods have been developed in order to produce these foams without using formaldehyde. TBRFs with and without formaldehyde are visually indistinguishable; therefore a method for determining the differences between these foams had to be found. The attenuated total reflectance infrared spectroscopy (ATR FT-IR investigation of the TBRFs presented in this paper allowed discrimination between the formaldehyde-containing (classic and formaldehyde-free TBRFs. The spectra of the formaldehyde-free TBRFs, indeed, present decreased band intensity related to the C–O stretching vibration of (i the methylol groups and (ii the furanic rings. This evidence served to prove the chemical difference between the two TBRFs and explained the slightly higher mechanical properties measured for the classic TBRFs.

  12. Reaction rate approach to dipolar relaxation in alkali halides: Adiabaticity versus classical, activated-tunneling, and quantal dipoles

    OpenAIRE

    Medrano, C; Georgiev, M.

    2007-01-01

    This paper is aimed at presenting a simple vibronic model for describing the dipolar reorientation in crystals by means of reaction rate theory. The Hamiltonian of an isolated dipole is simplified so as to render the problem solvable. Depending on the crossover splitting the dipoles may reorientate adiabatically with a high electron-transfer expectancy or exhibit low reorientation rates due to low expectancy. An important quantity to distinguish between adiabatic dipoles behaving classically ...

  13. Coupled Higgs field equation and Hamiltonian amplitude equation: Lie classical approach and (′/)-expansion method

    Indian Academy of Sciences (India)

    Sachin Kumar; K Singh; R K Gupta

    2012-07-01

    In this paper, coupled Higgs field equation are studied using the Lie classical method. Symmetry reductions and exact solutions are reported for Higgs equation and Hamiltonian amplitude equation. We also establish the travelling wave solutions involving parameters of the coupled Higgs equation and Hamiltonian amplitude equation using (′/)-expansion methodc, where = () satisfies a second-order linear ordinary differential equation (ODE). The travelling wave solutions expressed by hyperbolic, trigonometric and the rational functions are obtained.

  14. A supply side approach for estimating a Neo-classical fixed investment model for the South African economy

    OpenAIRE

    Ackerman Maarten

    2000-01-01

    Investment behaviour is influenced by a number of variables. A change in macro-econometric parameters can affect investment behaviour in a number of ways. The purpose of this study is to report the theory and estimation of an investment model for the South African economy. The model estimated in this study is mainly based on the neo-classical investment theory as part of the estimation of a consistent supply side, macro-econometric model for the South African economy. Equations for capital, f...

  15. Classical Motion

    CERN Document Server

    Mould, R A

    2003-01-01

    Preciously given rules allow conscious systems to be included in quantum mechanical systems. There rules are derived from the empirical experience of an observer who witnesses a quantum mechanical interaction leading to the capture of a single particle. In the present paper it is shown that purely classical changes experienced by an observer are consistent with these rules. Three different interactions are considered, two of which combine classical and quantum mechanical changes. The previously given rules support all of these cases. Key Words: brain states, conscious observer, detector, measurement, probability current, state reduction, von Neumann, wave collapse.

  16. Classical entanglement

    OpenAIRE

    Danforth, Douglas G.

    2001-01-01

    Classical systems can be entangled. Entanglement is defined by coincidence correlations. Quantum entanglement experiments can be mimicked by a mechanical system with a single conserved variable and 77.8% conditional efficiency. Experiments are replicated for four particle entanglement swapping and GHZ entanglement.

  17. Classical Mechanics

    OpenAIRE

    Gallavotti, Giovanni

    1999-01-01

    This is the English version of a friendly graduate course on Classical Mechanics, containing about 80% of the material I covered during the January-June 1999 semester at IFUG in the Mexican city of Leon. For the Spanish version, see physics/9906066

  18. Physics of classical electromagnetism

    CERN Document Server

    Fujimoto, Minoru

    2007-01-01

    The classical electromagnetism described by the Maxwell equations constitutes a fundamental law in contemporary physics. Even with the advent of sophisticated new materials, the principles of classical electromagnetism are still active in various applied areas in today’s advanced communication techniques. Physics of Classical Electromagnetism, by Minoru Fujimoto, is written with concise introductory arguments emphasizing the original field concept, with an aim at understanding objectives in modern information technology. Following basic discussions of electromagnetism with a modernized approach, this book will provide readers with an overview of current problems in high-frequency physics. To further the reader’s understanding of the concepts and applications discussed, each illustration within the book shows the location of all active charges, and the author has provided many worked-out examples throughout the book. Physics of Classical Electromagnetism is intended for students in physics and engineering ...

  19. Characterization of induced nanoplasmonic fields in time-resolved photoemission from gold nanospheres: a classical trajectory approach

    Science.gov (United States)

    Saydanzad, Erfan; Thumm, Uwe

    2016-05-01

    Attosecond time-resolved (XUV-pump, IR-probe) spectroscopy has been shown to be a powerful method for investigating the electron dynamics in atoms, and this technique is now being transferred to the investigation of electronic excitations, electron propagation, and collective electronic (plasmonic) effects in solids. Based on classical trajectory calculations, we simulated (i) the final photoelectron velocity distribution in order to provide observable velocity-map images for gold nanospheres of 10 and 100 nm diameter and (ii) streaked photoemission spectra. By analyzing our numerical results, we illustrate how spatio-temporal information about the sub-IR-cycle plasmonic and electronic dynamics is encoded in velocity-map images and streaked photoelectron spectra. Supported by the NE/KS NSF-EPSCOR program.

  20. Dynamical behaviours of the nonlinear atom-field interaction in the presence of classical gravity: f-deformation approach

    International Nuclear Information System (INIS)

    In this paper, we investigate the effects of a classical gravitational field on the dynamical behaviour of the nonlinear atom-field interaction within the framework of the f-deformed Jaynes-Cummings model. For this purpose, we first introduce a set of new atomic operators obeying an f-deformed su(2) algebraic structure to derive an effective Hamiltonian for the system under consideration. Then by solving the Schroedinger equation in the interaction picture and considering certain initial quantum states for the atomic and radiation subsystems, we analyse the influence of gravity on the temporal evolution of the atomic population inversion, atomic dipole squeezing, atomic momentum diffusion, photon counting statistics and deformed quadrature squeezing of the radiation field.

  1. Crises and Revolutions Philosophical approaches to their interdependence in the classic work of Rousseau, Kant, Tocqueville, Cassirer and Arendt

    Directory of Open Access Journals (Sweden)

    Roberto Aramayo

    2014-12-01

    Full Text Available http://dx.doi.org/10.5007/1677-2954.2014v13n2p303It is the sole topic of conversation throughout Europe. An economic crisis with an underlying crisis of values is devastating everything, while politics has nothing to say. An attempt was made to base the European Unión on a single currency, and the resulting traders’ Europeprevented the desired political project from bearing fruit. Instead of comparing different legal systems before creating a constitution for citizens, we have seen the birth of a new idolatry that is connected with a perverse fatalism. Only macroeconomic figures are considered to be important, while citizens have to suffer because of the actions of a few unscrupulous people who worship profit as well as having legalised usury.Given this situation it is necessary to take all types of precaution, and that is why it is a good idea to see what classical authors have to say. The Enlightenment seems to be a failed project that urgently needs to be restarted. It may be enormously useful to re-read Rousseau, as Cassirer did during the rise of Nazism so that it could be fought on the basis of the history of ideas. His discourse on inequality could not be more relevant now. And the same consideration applies to the genealogical study of the French revolution by Tocqueville. That was the revolution par excellence which Kant described as a symbol of the moral progress of mankind.

  2. Approach to the classical radiation biology. Ionizing radiation effects and repair mechanism of DNA double strand breaks

    International Nuclear Information System (INIS)

    Split-dose recovery has been observed under a variety of experimental conditions in many cell systems and believed to be the recovery of sublethal damage (SLD). It is considered to be one of the most widespread and important cellular responses in clinical radiotherapy. To study the molecular mechanism of this recovery, we analyzed the knockout mutants KU70-/-, RAD54-/-, and KU70-/-/ RAD54-/- of the chicken B-cell line, DT40. Rad54 participates in the homologous recombinational (HR) repair of DNA double-strand breaks (DSB), while Ku proteins are involved in non-homologous end-joining (NHEJ). Split-dose recovery was observed in the parent DT40 and KU70-/- cells. Moreover the split-dose survival enhancement had all of the characteristics of SLD recovery that had been demonstrated earlier: e.g., the reappearance of the shoulder of the survival curve with dose fractionation; repair at 25degC; and inhibition by the antibiotic actinomycin D. These results strongly suggest that SLD recovery is due to DSB repair via or mediated by HR, and that these breaks constitute SLD. The tonicity-sensitive potentially lethal damage (PLD) recovery was also found only in DT40 and KU70 -/- cells. Delayed-plating PLD recovery may be controlled by NHEJ repair that works through the cell cycle. These results lead to the conclusion that the repair of DSBs could explain the classical operational recovery phenomena. We have also investigated RBE/LET using those mutants. (author)

  3. Vibrationally enhanced associative photodesorption of H{sub 2} (D{sub 2}) from Ru(0001). Quantum and classical approaches

    Energy Technology Data Exchange (ETDEWEB)

    Vazhappilly, Tijo Joseph

    2008-04-15

    This thesis investigates the femtosecond laser induced associative photodesorption of hydrogen, H{sub 2}, and deuterium, D{sub 2}, from a ruthenium metal surface. One of the goals of the present thesis is to suggest, on the basis of theoretical simulations, strategies to control/enhance the photodesorption yield from Ru(0001). For this purpose, we suggest a hybrid scheme to control the reaction, where the adsorbate vibrations are initially excited by an infrared (IR) pulse, prior to the vis pulse. Both adiabatic and non-adiabatic representations for photoinduced desorption problems are employed here. The adiabatic representation is realized within the classical picture using Molecular Dynamics (MD) with electronic frictions. In a quantum mechanical description, non-adiabatic representations are employed within open-system density matrix theory. The time evolution of the desorption process is studied using a two-mode reduced dimensionality model with one vibrational coordinate and one translational coordinate of the adsorbate. The ground and excited electronic state potentials, and dipole function for the IR excitation are taken from first principles. The IR driven vibrational excitation of adsorbate modes with moderate efficiency is achieved by (modified) {pi}-pulses or/and optimal control theory. The fluence dependence of the desorption reaction is computed by including the electronic temperature of the metal calculated from the two-temperature model. We then employed the IR+vis strategy in both models. Here, we found that vibrational excitation indeed promotes the desorption of hydrogen and deuterium. (orig.)

  4. Quasi-classical trajectory approach to the stereo-dynamics of the reaction F+HO→HF+O

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Quasi-classical trajectory (QCT) calculations are employed for the reaction F + HO(0,0)→HF + O based on the adiabatic potential energy surface (PES) of the ground 3A″triplet state. The average rotational alignment factor as a function of collision energy and the four polarization dependent generalized differential cross sections have been calculated in the center-of-mass (CM) frame, separately. The distribution P(θr) of the angle between k and j′, the distribution P(θr) of dihedral angle denoting k-k′-j′ correlation, and the angular distribution P(θr, Φr) of product rotational vectors in the form of polar plots are calculated as well. The effect of Heavy-Light-Heavy (HLH) mass combination and atom F’s relatively strong absorbability to charges on the alignment and the orientation of product molecule HF rotational angular momentum vectors j′ is revealed.

  5. Approach to the classical radiation biology. Ionizing radiation effects and repair mechanism of DNA double strand breaks

    Energy Technology Data Exchange (ETDEWEB)

    Utsumi, Hiroshi [Kyoto Univ., Kumatori, Osaka (Japan). Research Reactor Inst

    2000-09-01

    Split-dose recovery has been observed under a variety of experimental conditions in many cell systems and believed to be the recovery of sublethal damage (SLD). It is considered to be one of the most widespread and important cellular responses in clinical radiotherapy. To study the molecular mechanism of this recovery, we analyzed the knockout mutants KU70{sup -/-}, RAD54{sup -/-}, and KU70{sup -/-}/ RAD54{sup -/-} of the chicken B-cell line, DT40. Rad54 participates in the homologous recombinational (HR) repair of DNA double-strand breaks (DSB), while Ku proteins are involved in non-homologous end-joining (NHEJ). Split-dose recovery was observed in the parent DT40 and KU70{sup -/-} cells. Moreover the split-dose survival enhancement had all of the characteristics of SLD recovery that had been demonstrated earlier: e.g., the reappearance of the shoulder of the survival curve with dose fractionation; repair at 25degC; and inhibition by the antibiotic actinomycin D. These results strongly suggest that SLD recovery is due to DSB repair via or mediated by HR, and that these breaks constitute SLD. The tonicity-sensitive potentially lethal damage (PLD) recovery was also found only in DT40 and KU70 {sup -/-} cells. Delayed-plating PLD recovery may be controlled by NHEJ repair that works through the cell cycle. These results lead to the conclusion that the repair of DSBs could explain the classical operational recovery phenomena. We have also investigated RBE/LET using those mutants. (author)

  6. Put the concert attendee in the spotlight: A user-centered design and development approach for classical concert applications

    NARCIS (Netherlands)

    Melenhorst, M.S.; Liem, C.C.S.

    2015-01-01

    As the importance of real-life use cases in the music information retrieval (MIR) field is increasing, so does the importance of understanding user needs. The development of innovative real-life applications that draw on MIR technology requires a user-centered design and development approach that as

  7. Classical tachyons

    International Nuclear Information System (INIS)

    A review of tachyons, with particular attention to their classical theory, is presented. The extension of Special Relativity to tachyons in two dimensional is first presented, an elegant model-theory which allows a better understanding also of ordinary physics. Then, the results are extended to the four-dimensional case (particular on tachyon mechanics) that can be derived without assuming the existence of Super-luminal reference-frames. Localizability and the unexpected apparent shape of tachyonic objects are discussed, and it is shown (on the basis of tachyon kinematics) how to solve the common causal paradoxes. In connection with General Relativity, particularly the problem of the apparent superluminal expansions in astrophysics is reviewed. The problem (still open) of the extension of relativitic theories to tachyons in four dimensions is tackled, and the electromagnetic theory of tachyons, a topic that can be relevant also for the experimental side, is reviewed. (Author)

  8. Archaeological, art-historical, and artistic approaches to classical antiquity. Viccy Coltman (ed., Making Sense of Greek Art, University of Exeter Press, 2012

    Directory of Open Access Journals (Sweden)

    Carol C. Mattusch

    2012-12-01

    Full Text Available Making sense of Greek Art is a Festschrift in memory of John Betts containing papers by ten of his students and colleagues. Their papers on Greek, Etruscan, Roman, and nineteenth-century topics reveal a wide range of methodologies. Two papers focus on subjects that might be covered in a course on Greek art and archaeology: one evaluates votive offerings in the sanctuary of Artemis Orthia at Sparta (Nicki Waugh; and the other compares archaeological and art-historical approaches to the study of Greek vases (Zosia Archibald. Three are concerned with Etruscan and Roman works: an Etruscan reinterpretation of a Greek myth (Vedia Izzet; Hellenistic and Roman versions of Aphrodite holding a mirror (Shelley Hales; and early Augustan uses of Archaistic art (Christopher H. Hallett. The other five papers illustrate the uses of classical artefacts during the nineteenth century: classical elements in Jacques-Louis David’s paintings (Ed Lilley; display of antiquities in the library of an English country house (Viccy Coltman; Tanagra figurines in paintings by Lawrence Alma-Tadema and Jean-Léon Gérôme (Genevieve Liveley; Alma-Tadema’s drawings for a theatrical production of Hypatia (Michael Liversidge; and plaster casts of the Elgin marbles exhibited in the Greek court of the Crystal Palace (Kate Nichols.

  9. Giant cystic meconium peritonitis presenting in a neonate with classic radiographic eggshell calcifications and treated with an elective surgical approach: a case report

    Directory of Open Access Journals (Sweden)

    Barthel Erik R

    2012-08-01

    Full Text Available Abstract Introduction Giant cystic meconium peritonitis is relatively rare. Patients often present with nonspecific physical findings such as distension and emesis. Plain abdominal films remain invaluable for identifying the characteristic calcifications seen with a meconium pseudocyst, and large eggshell calcifications are pathognomonic for the giant cystic subtype. Case presentation We present classic plain X-ray findings and an intraoperative image of a premature low birth weight two-day-old Hispanic male baby treated for giant cystic meconium peritonitis with a staged procedure involving peritoneal drainage, ostomy creation and closure. Conclusion Pediatric surgeons have a range of potential therapeutic approaches for giant cystic meconium peritonitis. A delay of definitive surgical management in the setting of massive abdominal soiling is a safe and acceptable strategy if adequate temporizing drainage is performed in the early perinatal period.

  10. CO2 intrusion in freshwater aquifers: Review of geochemical tracers and monitoring tools, classical uses and innovative approaches

    International Nuclear Information System (INIS)

    Highlights: • Review of applied geochemical methods for monitoring CO2 leak in fresh groundwater. • Application of multi-isotope approach for a powerful monitoring strategy. • Deciphering of chemical and isotopic signal associated with CO2 presence. • New perspectives on isotopic systematic not yet applied in the context of CCS. - Abstract: This review of applied geochemical methods for monitoring CO2 leakage focuses on shallow freshwater aquifers overlying CO2 storage areas. Geochemical tracer tools form a set of geochemical techniques, each of which is examined in this review and classified according to its sensitivity in CO2 detection. The purpose of any monitoring programme is to be able to provide sufficient information to enable site remediation in the case of unforeseen events and also to enable a satisfactory site closure strategy. Therefore, CO2 monitoring tools must be able to detect a precursor signal or an early warning signal of leakage associated with potentially minute geochemical modifications (i.e. associated with small amounts of CO2). We have classified the monitoring/tracing tools into two groups: (A) direct indicators of the CO2 itself, and (B) indirect indicators (i.e. reaction products) of the presence of CO2 that take into account displacement of the chemical equilibria under the conditions imposed by CO2 dissolution. Included in these tools are isotopic monitoring tools that are very sensitive to physico-chemical changes and can therefore provide early CO2 detection. These tools include carbon and oxygen isotope systematics that are conventionally used with respect to CO2 in the Carbon Capture and Storage (CCS) context. Finally, the review offers new perspectives on sensitive indirect detection methods using isotopes that are ‘non-traditional’ in the sense that they have not yet been applied to the field of CO2 geological storage. The complementarity of these geochemical methods provides a powerful monitoring strategy

  11. Estimating the probability of occurrence of earthquakes (M>6) in the Western part of the Corinth rift using fault-based and classical seismotectonic approaches.

    Science.gov (United States)

    Boiselet, Aurelien; Scotti, Oona; Lyon-Caen, Hélène

    2014-05-01

    The Corinth rift, Greece, is one of the regions with highest strain rates in the Euro-Mediterranean area and as such it has long been identified as a site of major importance for earthquake studies in Europe (20 years of research by the Corinth Rift Laboratory and 4 years of in-depth studies by the ANR-SISCOR project). This enhanced knowledge, acquired in particular, in the western part of the Gulf of Corinth, an area about 50 by 40 km, between the city of Patras to the west and the city of Aigion to the east, provides an excellent opportunity to compare fault-based and classical seismotectonic approaches currently used in seismic hazard assessment studies. A homogeneous earthquake catalogue was first constructed for the Greek territory based on two existing earthquake catalogues available for Greece (National Observatory of Athens and Thessaloniki). In spite of numerous documented damaging earthquakes, only a limited amount of macroseismic intensity data points are available in the existing databases for the damaging earthquakes affecting the west Corinth rift region. A re-interpretation of the macroseismic intensity field for numerous events was thus conducted, following an in-depth analysis of existing and newly found documentation (for details see Rovida et al. EGU2014-6346). In parallel, the construction of a comprehensive database of all relevant geological, geodetical and geophysical information (available in the literature and recently collected within the ANR-SISCOR project), allowed proposing rupture geometries for the different fault-systems identified in the study region. The combination of the new earthquake parameters and the newly defined fault geometries, together with the existing published paleoseismic data, allowed proposing a suite of rupture scenarios including the activation of multiple fault segments. The methodology used to achieve this goal consisted in setting up a logic tree that reflected the opinion of all the members of the ANR

  12. What was classical genetics?

    Science.gov (United States)

    Waters, C Kenneth

    2004-12-01

    I present an account of classical genetics to challenge theory-biased approaches in the philosophy of science. Philosophers typically assume that scientific knowledge is ultimately structured by explanatory reasoning and that research programs in well-established sciences are organized around efforts to fill out a central theory and extend its explanatory range. In the case of classical genetics, philosophers assume that the knowledge was structured by T. H. Morgan's theory of transmission and that research throughout the later 1920s, 30s, and 40s was organized around efforts to further validate, develop, and extend this theory, I show that classical genetics was structured by an integration of explanatory reasoning (associated with the transmission theory) and investigative strategies (such as the 'genetic approach'). The investigative strategies, which have been overlooked in historical and philosophical accounts, were as important as the so-called laws of Mendelian genetics. By the later 1920s, geneticists of the Morgan school were no longer organizing research around the goal of explaining inheritance patterns; rather, they were using genetics to investigate a range of biological phenomena that extended well beyond the explanatory domain of transmission theories. Theory-biased approaches in history and philosophy of science fail to reveal the overall structure of scientific knowledge and obscure the way it functions. PMID:15682554

  13. Absorption and emission spectral shapes of a prototype dye in water by combining classical/dynamical and quantum/static approaches.

    Science.gov (United States)

    Petrone, Alessio; Cerezo, Javier; Ferrer, Francisco J Avila; Donati, Greta; Improta, Roberto; Rega, Nadia; Santoro, Fabrizio

    2015-05-28

    We study the absorption and emission electronic spectra in an aqueous solution of N-methyl-6-oxyquinolinium betaine (MQ), an interesting dye characterized by a large change of polarity and H-bond ability between the ground (S0) and the excited (S1) states. To that end we compare alternative approaches based either on explicit solvent models and density functional theory (DFT)/molecular-mechanics (MM) calculations or on DFT calculations on clusters models embedded in a polarizable continuum (PCM). In the first approach (ClMD), the spectrum is computed according to the classical Franck-Condon principle, from the dispersion of the time-dependent (TD)-DFT vertical transitions at selected snapshots of molecular dynamics (MD) on the initial state. In the cluster model (Qst) the spectrum is simulated by computing the quantum vibronic structure, estimating the inhomogeneous broadening from state-specific TD-DFT/PCM solvent reorganization energies. While both approaches provide absorption and emission spectral shapes in nice agreement with experiment, the Stokes shift is perfectly reproduced by Qst calculations if S0 and S1 clusters are selected on the grounds of the MD trajectory. Furthermore, Qst spectra better fit the experimental line shape, mostly in absorption. Comparison of the predictions of the two approaches is very instructive: the positions of Qst and ClMD spectra are shifted due to the different solvent models and the ClMD spectra are narrower than the Qst ones, because MD underestimates the width of the vibrational density of states of the high-frequency modes coupled to the electronic transition. On the other hand, both Qst and ClMD approaches highlight that the solvent has multiple and potentially opposite effects on the spectral width, so that the broadening due to solute-solvent vibrations and electrostatic interaction with bulk solvent is (partially) counterbalanced by a narrowing of the contribution due to the solute vibrational modes. Qst analysis

  14. Randomness: quantum versus classical

    CERN Document Server

    Khrennikov, Andrei

    2015-01-01

    Recent tremendous development of quantum information theory led to a number of quantum technological projects, e.g., quantum random generators. This development stimulates a new wave of interest in quantum foundations. One of the most intriguing problems of quantum foundations is elaboration of a consistent and commonly accepted interpretation of quantum state. Closely related problem is clarification of the notion of quantum randomness and its interrelation with classical randomness. In this short review we shall discuss basics of classical theory of randomness (which by itself is very complex and characterized by diversity of approaches) and compare it with irreducible quantum randomness. The second part of this review is devoted to the information interpretation of quantum mechanics (QM) in the spirit of Zeilinger and Brukner (and QBism of Fuchs et al.) and physics in general (e.g., Wheeler's "it from bit") as well as digital philosophy of Chaitin (with historical coupling to ideas of Leibnitz). Finally, w...

  15. Classical Diophantine equations

    CERN Document Server

    1993-01-01

    The author had initiated a revision and translation of "Classical Diophantine Equations" prior to his death. Given the rapid advances in transcendence theory and diophantine approximation over recent years, one might fear that the present work, originally published in Russian in 1982, is mostly superseded. That is not so. A certain amount of updating had been prepared by the author himself before his untimely death. Some further revision was prepared by close colleagues. The first seven chapters provide a detailed, virtually exhaustive, discussion of the theory of lower bounds for linear forms in the logarithms of algebraic numbers and its applications to obtaining upper bounds for solutions to the eponymous classical diophantine equations. The detail may seem stark--- the author fears that the reader may react much as does the tourist on first seeing the centre Pompidou; notwithstanding that, Sprind zuk maintainsa pleasant and chatty approach, full of wise and interesting remarks. His emphases well warrant, ...

  16. A NOVEL APPROACH TO TRANSFORM CLASSICAL DATABASE TO USER FRIENDLY WEB DOCUMENT FOR MEDICAL APPLICATION IN PEER-TO-PEER ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    E. Anupriya,

    2010-11-01

    Full Text Available Due to the increasing popularity of the XML (eXtensible Markup Language as a common data standard for information interchange across Web, XML is commonly being used as an underlying data model for many applications to deal with the heterogeneity of data and nodes. This paper presents a novel approach to extract data from classical database systems like relational database systems, convert it into XML documents, and exchange XML documents among peer nodes in the network. Many hospitals have branches in different geographicallocations. The chief doctors need to travel to different locations and give consultation. If the peer hospital nodes are connected in peer-to-peer network, then the consultation can be provided from any peer hospital node even under emergencies. Peer-to-Peer network is implemented via Byzantine-Resilient Secure Multicast Routing in ultihop Wireless Networks (BSMR protocol enhanced with security. Also, we have considered and emulated a system for one such medical application in which the consultant can enter details like insulin dosage to be given or any pre or post sugar measurements need to be taken for any in patients available in the peer hospitals. The concerned duty doctor and nurses can carryout the task based on instruction in any peer hospital node. To make it easily readable,the information is presented in browser as a XML document.

  17. Decoherence and energy relaxation in the quantum-classical dynamics for charge transport in organic semiconducting crystals: An instantaneous decoherence correction approach

    International Nuclear Information System (INIS)

    We explore an instantaneous decoherence correction (IDC) approach for the decoherence and energy relaxation in the quantum-classical dynamics of charge transport in organic semiconducting crystals. These effects, originating from environmental fluctuations, are essential ingredients of the carrier dynamics. The IDC is carried out by measurement-like operations in the adiabatic representation. While decoherence is inherent in the IDC, energy relaxation is taken into account by considering the detailed balance through the introduction of energy-dependent reweighing factors, which could be either Boltzmann (IDC-BM) or Miller-Abrahams (IDC-MA) type. For a non-diagonal electron-phonon coupling model, it is shown that IDC tends to enhance diffusion while energy relaxation weakens this enhancement. As expected, both the IDC-BM and IDC-MA achieve a near-equilibrium distribution at finite temperatures in the diffusion process, while in the Ehrenfest dynamics the electronic system tends to infinite temperature limit. The resulting energy relaxation times with the two kinds of factors lie in different regimes and exhibit different dependences on temperature, decoherence time, and electron-phonon coupling strength, due to different dominant relaxation processes

  18. Classical dynamics a modern perspective

    CERN Document Server

    Sudarshan, Ennackal Chandy George

    2016-01-01

    Classical dynamics is traditionally treated as an early stage in the development of physics, a stage that has long been superseded by more ambitious theories. Here, in this book, classical dynamics is treated as a subject on its own as well as a research frontier. Incorporating insights gained over the past several decades, the essential principles of classical dynamics are presented, while demonstrating that a number of key results originally considered only in the context of quantum theory and particle physics, have their foundations in classical dynamics.Graduate students in physics and practicing physicists will welcome the present approach to classical dynamics that encompasses systems of particles, free and interacting fields, and coupled systems. Lie groups and Lie algebras are incorporated at a basic level and are used in describing space-time symmetry groups. There is an extensive discussion on constrained systems, Dirac brackets and their geometrical interpretation. The Lie-algebraic description of ...

  19. New insights into the nonadiabatic state population dynamics of model proton-coupled electron transfer reactions from the mixed quantum-classical Liouville approach

    International Nuclear Information System (INIS)

    In a previous study [F. A. Shakib and G. Hanna, J. Chem. Phys. 141, 044122 (2014)], we investigated a model proton-coupled electron transfer (PCET) reaction via the mixed quantum-classical Liouville (MQCL) approach and found that the trajectories spend the majority of their time on the mean of two coherently coupled adiabatic potential energy surfaces. This suggested a need for mean surface evolution to accurately simulate observables related to ultrafast PCET processes. In this study, we simulate the time-dependent populations of the three lowest adiabatic states in the ET-PT (i.e., electron transfer preceding proton transfer) version of the same PCET model via the MQCL approach and compare them to the exact quantum results and those obtained via the fewest switches surface hopping (FSSH) approach. We find that the MQCL population profiles are in good agreement with the exact quantum results and show a significant improvement over the FSSH results. All of the mean surfaces are shown to play a direct role in the dynamics of the state populations. Interestingly, our results indicate that the population transfer to the second-excited state can be mediated by dynamics on the mean of the ground and second-excited state surfaces, as part of a sequence of nonadiabatic transitions that bypasses the first-excited state surface altogether. This is made possible through nonadiabatic transitions between different mean surfaces, which is the manifestation of coherence transfer in MQCL dynamics. We also investigate the effect of the strength of the coupling between the proton/electron and the solvent coordinate on the state population dynamics. Drastic changes in the population dynamics are observed, which can be understood in terms of the changes in the potential energy surfaces and the nonadiabatic couplings. Finally, we investigate the state population dynamics in the PT-ET (i.e., proton transfer preceding electron transfer) and concerted versions of the model. The PT

  20. New insights into the nonadiabatic state population dynamics of model proton-coupled electron transfer reactions from the mixed quantum-classical Liouville approach

    Energy Technology Data Exchange (ETDEWEB)

    Shakib, Farnaz A.; Hanna, Gabriel, E-mail: gabriel.hanna@ualberta.ca [Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2 (Canada)

    2016-01-14

    In a previous study [F. A. Shakib and G. Hanna, J. Chem. Phys. 141, 044122 (2014)], we investigated a model proton-coupled electron transfer (PCET) reaction via the mixed quantum-classical Liouville (MQCL) approach and found that the trajectories spend the majority of their time on the mean of two coherently coupled adiabatic potential energy surfaces. This suggested a need for mean surface evolution to accurately simulate observables related to ultrafast PCET processes. In this study, we simulate the time-dependent populations of the three lowest adiabatic states in the ET-PT (i.e., electron transfer preceding proton transfer) version of the same PCET model via the MQCL approach and compare them to the exact quantum results and those obtained via the fewest switches surface hopping (FSSH) approach. We find that the MQCL population profiles are in good agreement with the exact quantum results and show a significant improvement over the FSSH results. All of the mean surfaces are shown to play a direct role in the dynamics of the state populations. Interestingly, our results indicate that the population transfer to the second-excited state can be mediated by dynamics on the mean of the ground and second-excited state surfaces, as part of a sequence of nonadiabatic transitions that bypasses the first-excited state surface altogether. This is made possible through nonadiabatic transitions between different mean surfaces, which is the manifestation of coherence transfer in MQCL dynamics. We also investigate the effect of the strength of the coupling between the proton/electron and the solvent coordinate on the state population dynamics. Drastic changes in the population dynamics are observed, which can be understood in terms of the changes in the potential energy surfaces and the nonadiabatic couplings. Finally, we investigate the state population dynamics in the PT-ET (i.e., proton transfer preceding electron transfer) and concerted versions of the model. The PT

  1. New insights into the nonadiabatic state population dynamics of model proton-coupled electron transfer reactions from the mixed quantum-classical Liouville approach

    Science.gov (United States)

    Shakib, Farnaz A.; Hanna, Gabriel

    2016-01-01

    In a previous study [F. A. Shakib and G. Hanna, J. Chem. Phys. 141, 044122 (2014)], we investigated a model proton-coupled electron transfer (PCET) reaction via the mixed quantum-classical Liouville (MQCL) approach and found that the trajectories spend the majority of their time on the mean of two coherently coupled adiabatic potential energy surfaces. This suggested a need for mean surface evolution to accurately simulate observables related to ultrafast PCET processes. In this study, we simulate the time-dependent populations of the three lowest adiabatic states in the ET-PT (i.e., electron transfer preceding proton transfer) version of the same PCET model via the MQCL approach and compare them to the exact quantum results and those obtained via the fewest switches surface hopping (FSSH) approach. We find that the MQCL population profiles are in good agreement with the exact quantum results and show a significant improvement over the FSSH results. All of the mean surfaces are shown to play a direct role in the dynamics of the state populations. Interestingly, our results indicate that the population transfer to the second-excited state can be mediated by dynamics on the mean of the ground and second-excited state surfaces, as part of a sequence of nonadiabatic transitions that bypasses the first-excited state surface altogether. This is made possible through nonadiabatic transitions between different mean surfaces, which is the manifestation of coherence transfer in MQCL dynamics. We also investigate the effect of the strength of the coupling between the proton/electron and the solvent coordinate on the state population dynamics. Drastic changes in the population dynamics are observed, which can be understood in terms of the changes in the potential energy surfaces and the nonadiabatic couplings. Finally, we investigate the state population dynamics in the PT-ET (i.e., proton transfer preceding electron transfer) and concerted versions of the model. The PT

  2. Simultaneous retrieval of aerosols and ocean properties: A classic inverse modeling approach. I. Analytic Jacobians from the linearized CAO-DISORT model

    International Nuclear Information System (INIS)

    In this paper and the sequel, we investigate the application of classic inverse methods based on iterative least-squares cost-function minimization to the simultaneous retrieval of aerosol and ocean properties from visible and near infrared spectral radiance measurements such as those from the SeaWiFS and MODIS instruments. Radiance measurements at the satellite are simulated directly using an accurate coupled atmosphere-ocean-discrete-ordinate radiative transfer (CAO-DISORT) code as the main component of the forward model. For this kind of cost-function inverse problem, we require the forward model to generate weighting functions (radiance partial derivatives) with respect to the aerosol and marine properties to be retrieved, and to other model parameters which are sources of error in the retrievals. In this paper, we report on the linearization of the CAO-DISORT model. This linearization provides a complete analytic differentiation of the coupled-media radiative transfer theory, and it allows the model to generate analytic weighting functions for any atmospheric or marine parameter. For high solar zenith angles, we give an implementation of the pseudo-spherical (P-S) approach to solar beam attenuation in the atmosphere in the linearized model. We summarize a number of performance enhancements such as the use of an exact single-scattering calculation to improve accuracy. We derive inherent optical property inputs for the linearized CAO-DISORT code for a simple 2-parameter bio-optical model for the marine environment coupled to a 2-parameter bimodal atmospheric aerosol medium

  3. Trends in AIDS Incidence in Individuals Aged 50 Years or Older in the City of Rio de Janeiro, Brazil, 1982–2011: An Age-Period-Cohort Analysis

    Directory of Open Access Journals (Sweden)

    Paulo Cavalcante Apratto Junior

    2014-07-01

    Full Text Available Objective: The aim of this study was to investigate the effects of three temporal components of AIDS incidence (i.e., age, period and cohort on individuals aged 50 or older living in Niteroi, Rio de Janeiro (Brazil. Methods: Age-specific incidence rates were calculated from 1982–2011. Negative binomial and Poisson models were used to analyze the risk of AIDS by age, period and cohort. Results: The risk of AIDS in men was 2.45 times higher than in women, regardless of age and period (p-value < 0.001. The incidence of AIDS in individuals older than 69 years was 7-fold lower than in those aged 50–59 years (p-value < 0.001. A decreasing trend in AIDS risk was observed from the youngest cohort (≥1940 to the oldest (1910–1919. From 1982 to 2006, we could detect an increasing trend in AIDS risk in the population aged 50 years or older. A peak in rates was detected in the period from 2002–2006. The incidence rates in 2002–2006 were six times higher than those in 1987–1991 (p-value < 0.001, independent of age and sex (p-value < 0.001. Conclusions: An increase of AIDS risk in older people was detected. This group should not be neglected by public health programs.

  4. Forty-Year Trends in Tooth Loss Among American Adults With and Without Diabetes Mellitus: An Age-Period-Cohort Analysis

    OpenAIRE

    Luo, Huabin; Pan, Wei; Sloan, Frank; Feinglos, Mark; Wu, Bei

    2015-01-01

    Introduction This study aimed to assess the trends in tooth loss among adults with and without diabetes mellitus in the United States and racial/ethnic disparities in tooth loss patterns, and to evaluate trends in tooth loss by age, birth cohorts, and survey periods. Methods Data came from 9 waves of the National Health and Nutrition Examination Survey (NHANES) from 1971 through 2012. The trends in the estimated tooth loss in people with and without diabetes were assessed by age groups, surve...

  5. Cooperative Tracking and Disturbance Suppression: A Classical Approach%基于经典理论的协作跟踪与干扰抑制技术

    Institute of Scientific and Technical Information of China (English)

    黄超; 何衍; 叶旭东

    2011-01-01

    In this paper, the cooperative tracking problem of multiagent systems with a determinate disturbance input is analyzed. The communication topology of single-input-single-output (SISO) general linear node dynamics is directed and time invariant. Throughout this paper, the distributed control issue of multiagent systems is viewed and tackled as an output regulation problem and a distributed cooperative control law based on relative output measurements is proposed using classic pole assignment technique. Moreover, the notion of complex vector root locus (CVRL) is introduced, which is a generalization of classical root locus method, to analyze the stability of the control system.

  6. What classicality? Decoherence and Bohr's classical concepts

    CERN Document Server

    Schlosshauer, Maximilian

    2010-01-01

    Niels Bohr famously insisted on the indispensability of what he termed "classical concepts." In the context of the decoherence program, on the other hand, it has become fashionable to talk about the "dynamical emergence of classicality" from the quantum formalism alone. Does this mean that decoherence challenges Bohr's dictum and signifies a break with the Copenhagen interpretation-for example, that classical concepts do not need to be assumed but can be derived? In this paper we'll try to shine some light down the murky waters where formalism and philosophy cohabitate. To begin, we'll clarify the notion of classicality in the decoherence description. We'll then discuss Bohr's and Heisenberg's take on the quantum-classical problem and reflect on different meanings of the terms "classicality" and "classical concepts" in the writings of Bohr and his followers. This analysis will allow us to put forward some tentative suggestions for how we may better understand the relation between decoherence-induced classical...

  7. The Wigner representation of classical mechanics, quantization and classical limit

    International Nuclear Information System (INIS)

    Starting from the Liouvillian formulation of classical physics it is possible by means of a Fourier transform to introduce the Wigner representation and to derive an operator structure to classical mechanisms. The importance of this new representation lies on the fact that it turns out to be suitable route to establish a general method of quantization directly from the equations of motion without alluding to the existence of Hamiltonian and Lagrangian functions. Following this approach we quantize only the motion of a Browian particle with non-linear friction in the Markovian approximation - the thermal bath may be quantum or classical -, thus when the bath is classically described we obtain a master equation which reduces to Caldeira-Legget equation for the linear friction case, and when the reservoir is quantum we get an equation reducing to the one found by Caldeira et al. By neglecting the environmental influence we show that the system can be approximately described by equations of motion in terms of wave function, such as the Schrodinger-Langevin equation and equations of the Caldirola-Kanai type. Finally to make the present study self-consistent we evaluate the classical limit of these dynamical equations employing a new classical limiting method h/2π → 0. (author)

  8. Molecular Study of nifH1, nifH2, nifH3, nifU, nifV, VF Genes and Classical Approach Cared out to Identification of Azotobacter chrococcum from Soil

    OpenAIRE

    Adel Kamal Khider

    2012-01-01

    The present study aimed to compare classical approach with molecular based method for identification of Azotobacter chrococcum from soil samples. A. chrococcum was isolated from soil source in Erbil city, Iraq. They were cultivated under laboratory conditions using Nitrogen free Azotobacter specific medium. A. chrococcum was present in all soil samples. result shows that A. chrococcum were rod shape, motility occur through the use of peritrichous flagella, cysts-forming, positive to oxidase, ...

  9. Low-temperature VRH conduction through complex materials in the presence of a temperature-dependent voltage threshold: A semi-classical percolative approach

    International Nuclear Information System (INIS)

    In this paper, we study the variation of low temperature (T) dc conductance, G(T), of a semi-classical percolative Random Resistor cum Tunneling-bond Network (RRTN), in the presence of a linearly temperature-dependent microscopic voltage threshold, υg(T). This model (proposed by our group in the early 90's) considers a phenomenological semi-classical tunneling (or, hopping through a barrier) process. Just as in our previous constant-υg case, we find in the present study also that the variable range hopping (VRH) exponent γ varies continuously with the ohmic concentration p in a non-monotonic fashion. In addition, we observe a new shoulder-like behaviour of G(T) in the intermediate temperature range, below the conductance maximum. (author)

  10. A Pharmacological Approach to Medicinal Trees Described in the Classical Texts of Persian Traditional Medicine which do not Occur or No Longer Grow in Iran at Present

    Directory of Open Access Journals (Sweden)

    Peyman Mikaili

    2012-02-01

    Full Text Available The aim of this study was historically and pharmacologically reviewing almost all the known medicinal trees mentioned in classical texts of Persian traditional herbal medicine, which are not present or do no longer grow in Iran today. We have reviewed all important historical and modern literature about the medicinal trees and shrub used in Iranian traditional medicine. Then we selected the major references and collected the data. All plants, which were mentioned in classical texts of Iranian traditional herbal medicine, but do not occur or no longer grow in Iran at present. We compared the modern and traditional documented herbal medicine of our country and edited them as follow. All data about the terminology (if necessary some etymological information have been provided, local and native names, comparison the modern and traditional terminology and postulations about the plants, description about the medicinal parts of the plant, and finally the proposed medicinal and pharmacological activities of the trees have been presented. The collected data were represented as twenty-three species of trees and shrubs which were mentioned in classical texts of Iranian traditional herbal medicine, but are not reported as spontaneous in Iran at present. It is interesting that almost all of these plants have been described in the classical texts of Iranian herbal medicine. These data show that Persian scholars knew these trees in the earlier times. We may suppose the following probabilities for this controversy. The Persian scholars may were aware of these plants from Arabic, Indic or Greek-Roman tradition without seeing them closely. But it is known that the usage of the plants was common among Iranian herbalists and scholars in the past centuries. We propose more researches about these plants and the exact cause of their earlier presence and accessibility to the Persians in the history and the lack of their presence today in Iran.

  11. Simulation of planar channeling-radiation spectra of relativistic electrons and positrons channeled in a diamond-structure or tungsten single crystal (classical approach)

    Science.gov (United States)

    Azadegan, B.; Wagner, W.

    2015-01-01

    We present a Mathematica package for simulation of spectral-angular distributions and energy spectra of planar channeling radiation of relativistic electrons and positrons channeled along major crystallographic planes of a diamond-structure or tungsten single crystal. The program is based on the classical theory of channeling radiation which has been successfully applied to study planar channeling of light charged particles at energies higher than 100 MeV. Continuous potentials for different planes of diamond, Si, Ge and W single crystals are calculated using the Doyle-Turner approximation to the atomic scattering factor and taking thermal vibrations of the crystal atoms into account. Numerical methods are applied to solve the classical one-dimensional equation of motion. The code is designed to calculate the trajectories, velocities and accelerations of electrons (positrons) channeled by the planar continuous potential. In the framework of classical electrodynamics, these data allow realistic simulations of spectral-angular distributions and energy spectra of planar channeling radiation. Since the generated output is quantitative, the results of calculation may be useful, e.g., for setup configuration and crystal alignment in channeling experiments, for the study of the dependence of channeling radiation on the input parameters of particle beams with respect to the crystal orientation, but also for the simulation of positron production by means of pair creation what is mandatory for the design of efficient positron sources necessary in high-energy and collider physics. Although the classical theory of channeling is well established for long time, there is no adequate library program for simulation of channeling radiation up to now, which is commonly available, sufficiently simple and effective to employ and, therefore, of benefit as for special investigations as for a quick overview of basic features of this type of radiation.

  12. Approaches to the Cultivating of Individual Morality in Ancient Academy of Classical Learning%古代书院个体品德培育的途径

    Institute of Scientific and Technical Information of China (English)

    杜华伟; 赵伟

    2011-01-01

    With Confucian educational ideas,ancient academy of classical learning came to develop their own mode of cultivating individual morality after long education practice.That is,the practice of individual morality would be facilitated through deep understanding of classical connotation and following activities.A comprehensive analysis of cultivating of individual morality in ancient academy of classical learning can provide a realistic reference to modern morality education.%古代书院秉承儒家"德育为先"的教育理念,在长期教育实践过程中,形成了系统有效且独具特色的个体品德培育模式,即通过挖掘经典著作道德内涵、强化社会游历道德功能、深化书院祭祀道德意蕴,最终促成生徒个体自觉道德践履。

  13. Classical analogy of Fano resonances

    International Nuclear Information System (INIS)

    We present an analogy of Fano resonances in quantum interference to classical resonances in the harmonic oscillator system. It has a manifestation as a coupled behaviour of two effective oscillators associated with propagating and evanescent waves. We illustrate this point by considering a classical system of two coupled oscillators and interfering electron waves in a quasi-one-dimensional narrow constriction with a quantum dot. Our approach provides a novel insight into Fano resonance physics and provides a helpful view in teaching Fano resonances

  14. Principal bundles the classical case

    CERN Document Server

    Sontz, Stephen Bruce

    2015-01-01

    This introductory graduate level text provides a relatively quick path to a special topic in classical differential geometry: principal bundles.  While the topic of principal bundles in differential geometry has become classic, even standard, material in the modern graduate mathematics curriculum, the unique approach taken in this text presents the material in a way that is intuitive for both students of mathematics and of physics. The goal of this book is to present important, modern geometric ideas in a form readily accessible to students and researchers in both the physics and mathematics communities, providing each with an understanding and appreciation of the language and ideas of the other.

  15. Communication: Wigner functions in action-angle variables, Bohr-Sommerfeld quantization, the Heisenberg correspondence principle, and a symmetrical quasi-classical approach to the full electronic density matrix.

    Science.gov (United States)

    Miller, William H; Cotton, Stephen J

    2016-08-28

    It is pointed out that the classical phase space distribution in action-angle (a-a) variables obtained from a Wigner function depends on how the calculation is carried out: if one computes the standard Wigner function in Cartesian variables (p, x), and then replaces p and x by their expressions in terms of a-a variables, one obtains a different result than if the Wigner function is computed directly in terms of the a-a variables. Furthermore, the latter procedure gives a result more consistent with classical and semiclassical theory-e.g., by incorporating the Bohr-Sommerfeld quantization condition (quantum states defined by integer values of the action variable) as well as the Heisenberg correspondence principle for matrix elements of an operator between such states-and has also been shown to be more accurate when applied to electronically non-adiabatic applications as implemented within the recently developed symmetrical quasi-classical (SQC) Meyer-Miller (MM) approach. Moreover, use of the Wigner function (obtained directly) in a-a variables shows how our standard SQC/MM approach can be used to obtain off-diagonal elements of the electronic density matrix by processing in a different way the same set of trajectories already used (in the SQC/MM methodology) to obtain the diagonal elements. PMID:27586896

  16. Methods for evaluating physical processes in strong external fields at e{sup +}e{sup -} colliders. Furry picture and quasi-classical approach

    Energy Technology Data Exchange (ETDEWEB)

    Porto, Stefano [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Hartin, Anthony [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Moortgat-Pick, Gudrid [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2013-04-15

    Future linear colliders designs, ILC and CLIC, are expected to be powerful machines for the discovery of Physics Beyond the Standard Model and subsequent precision studies. However, due to the intense beams (high luminosity, high energy), strong electromagnetic fields occur in the beam-beam interaction region. In the context of precision high energy physics, the presence of such strong fields may yield sensitive corrections to the observed electron-positron processes. The Furry picture of quantum states gives a conceptually simple tool to treat physics processes in an external field. A generalization of the quasi-classical operator method (QOM) as an approximation is considered too.

  17. Bidirectional coherent classical communication

    OpenAIRE

    Harrow, Aram W.; Leung, Debbie W.

    2005-01-01

    A unitary interaction coupling two parties enables quantum or classical communication in both the forward and backward directions. Each communication capacity can be thought of as a tradeoff between the achievable rates of specific types of forward and backward communication. Our first result shows that for any bipartite unitary gate, bidirectional coherent classical communication is no more difficult than bidirectional classical communication — they have the same achievable rate regions. ...

  18. Entanglement in Classical Optics

    OpenAIRE

    Ghose, Partha; Mukherjee, Anirban

    2013-01-01

    The emerging field of entanglement or nonseparability in classical optics is reviewed, and its similarities with and differences from quantum entanglement clearly pointed out through a recapitulation of Hilbert spaces in general, the special restrictions on Hilbert spaces imposed in quantum mechanics and the role of Hilbert spaces in classical polarization optics. The production of Bell-like states in classical polarization optics is discussed, and new theorems are proved to discriminate betw...

  19. Classical, Semi-classical and Quantum Noise

    CERN Document Server

    Poor, H; Scully, Marlan

    2012-01-01

    David Middleton was a towering figure of 20th Century engineering and science and one of the founders of statistical communication theory. During the second World War, the young David Middleton, working with Van Fleck, devised the notion of the matched filter, which is the most basic method used for detecting signals in noise. Over the intervening six decades, the contributions of Middleton have become classics. This collection of essays by leading scientists, engineers and colleagues of David are in his honor and reflect the wide  influence that he has had on many fields. Also included is the introduction by Middleton to his forthcoming book, which gives a wonderful view of the field of communication, its history and his own views on the field that he developed over the past 60 years. Focusing on classical noise modeling and applications, Classical, Semi-Classical and Quantum Noise includes coverage of statistical communication theory, non-stationary noise, molecular footprints, noise suppression, Quantum e...

  20. Teleportation via classical entanglement

    CERN Document Server

    Rafsanjani, Seyed Mohammad Hashemi; Magaña-Loaiza, Omar S; Boyd, Robert W

    2015-01-01

    We present a classical counterpart to quantum teleportation that uses classical entanglement instead of quantum entanglement. In our implementation we take advantage of classical entanglement among three parties: orbital angular momentum (OAM), polarization, and the radial degrees of freedom of a beam of light. We demonstrate the teleportation of arbitrary OAM states, in the subspace spanned by any two OAM states, to the polarization of the same beam. Our letter presents the first classical demonstration of a commonly-perceived--quantum phenomenon that requires entanglement among more than two parties.

  1. Molecular dynamics study of the coordination sphere of trivalent lanthanum in a highly concentrated LiCl aqueous solution: A combined classical and ab initio approach

    International Nuclear Information System (INIS)

    The first coordination sphere of trivalent lanthanum in a highly concentrated (14 M) lithium chloride solution is studied with a combination of classical molecular dynamics and density functional theory based first principle molecular dynamics. This method enables us to obtain a solvation shell of La3+ containing 2 chloride ions and 6 water molecules. After refinement using first principle molecular dynamics, the resulting cation-water and cation-anion distances are in very good agreement with experiment. The 2 Cl- and the 6 water molecules arrange in a square anti-prism around La3+. Exchange of water molecules was also observed in the first-principle simulation, with an intermediate structure comprising 7 water molecules stable for 2.5 ps. Finally, evaluation of dipole moments using maximally localized Wannier functions shows a substantial polarization of the chloride anions and the water molecules in the first solvation shell of trivalent lanthanum. (authors)

  2. Effects of combined and classic training on different isometric rate of force development parameters of leg extensors in female volleyball players: Discriminative analysis approach

    Directory of Open Access Journals (Sweden)

    Rajić Branislav

    2013-01-01

    Full Text Available Background: The aim of this study is to verify the effects of the combined and classic training of different isometric rates of force development (RFD parameters of legs. Materials and Methods: Three groups of female athletes was tested: Experimental group (N = 12, classically trained group (N = 11, and control group (N = 20 of athletes. The isometric "standing leg extension" and "Rise on Toes" tests were conducted to evaluate the maximal force, time necessary time to reach it and the RFD analyzed at 100 ms, 180 ms, 250 ms from the onset, and 50-100% of its maximal result. Results: The maximal RFD of legs and calves are dominant explosive parameters. Special training enhanced the RFD of calves of GROUP SPEC at 100 ms (P = 0.05, at 180 ms (P = 0.039, at 250 ms (P = 0.039, at 50% of the F max (P = 0.031 and the F max (P = 0.05. Domination of GROUP SPEC toward GROUP CLASS and GROUP CONTROL is in case of legs at 100 ms (P = 0.04; at 180 ms (P = 0.04; at 250 ms (P = 0.00; at 50% of the F max (P = 0.01 and at the F max (P = 0.00; in case of calves at 100 ms (P = 0.07; 180 ms (P = 0.001; at 250 ms (P = 0.00; at 50% of the F max (P = 0.00 and at F max (P = 0.000. Conclusion: Dominant explosive factors are maximal RFD of leg extensors and calves, and legs at 250ms. Specific training enhanced explosiveness of calves of GROUP SPEC general and partial domination of GROUP SPEC by 87% over GROUP CLASS , and 35% over GROUP CONTROL .

  3. Semi-classical approximations based on Bohmian mechanics

    CERN Document Server

    Struyve, Ward

    2015-01-01

    Semi-classical theories are approximations to quantum theory that treat some degrees of freedom classically and others quantum mechanically. In the usual approach, the quantum degrees of freedom are described by a wave function which evolves according to some Schr\\"odinger equation with a Hamiltonian that depends on the classical degrees of freedom. The classical degrees of freedom satisfy classical equations that depend on the expectation values of quantum operators. In this paper, we study an alternative approach based on Bohmian mechanics. In this approach the quantum system is not only described by the wave function, but with additional variables such as particle positions or fields. By letting the classical equations of motion depend on these variables, rather than the quantum expectation values, a semi-classical approximation is obtained that is closer to the exact quantum results than the usual approach. We discuss the Bohmian semi-classical approximation in various context, such as non-relativistic qu...

  4. Semi-classical signal analysis

    CERN Document Server

    Laleg-Kirati, Taous-Meriem; Sorine, Michel

    2010-01-01

    This study introduces a new signal analysis method called SCSA, based on a semi-classical approach. The main idea in the SCSA is to interpret a pulse-shaped signal as a potential of a Schr\\"odinger operator and then to use the discrete spectrum of this operator for the analysis of the signal. We present some numerical examples and the first results obtained with this method on the analysis of arterial blood pressure waveforms.

  5. Semi-classical signal analysis

    KAUST Repository

    Laleg-Kirati, Taous-Meriem

    2012-09-30

    This study introduces a new signal analysis method, based on a semi-classical approach. The main idea in this method is to interpret a pulse-shaped signal as a potential of a Schrödinger operator and then to use the discrete spectrum of this operator for the analysis of the signal. We present some numerical examples and the first results obtained with this method on the analysis of arterial blood pressure waveforms. © 2012 Springer-Verlag London Limited.

  6. Classical competing risks

    CERN Document Server

    Crowder, Martin J

    2001-01-01

    If something can fail, it can often fail in one of several ways and sometimes in more than one way at a time. There is always some cause of failure, and almost always, more than one possible cause. In one sense, then, survival analysis is a lost cause. The methods of Competing Risks have often been neglected in the survival analysis literature. Written by a leading statistician, Classical Competing Risks thoroughly examines the probability framework and statistical analysis of data of Competing Risks. The author explores both the theory of the subject and the practicalities of fitting the models to data. In a coherent, self-contained, and sequential account, the treatment moves from the bare bones of the Competing Risks setup and the associated likelihood functions through survival analysis using hazard functions. It examines discrete failure times and the difficulties of identifiability, and concludes with an introduction to the counting-process approach and the associated martingale theory.With a dearth of ...

  7. Lectures on Classical Integrability

    CERN Document Server

    Torrielli, Alessandro

    2016-01-01

    We review some essential aspects of classically integrable systems. The detailed outline of the lectures consists of: 1. Introduction and motivation, with historical remarks; 2. Liouville theorem and action-angle variables, with examples (harmonic oscillator, Kepler problem); 3. Algebraic tools: Lax pairs, monodromy and transfer matrices, classical r-matrices and exchange relations, non-ultralocal Poisson brackets, with examples (non-linear Schroedinger model, principal chiral field); 4. Features of classical r-matrices: Belavin-Drinfeld theorems, analyticity properties, and lift of the classical structures to quantum groups; 5. Classical inverse scattering method to solve integrable differential equations: soliton solutions, spectral properties and the Gel'fand-Levitan-Marchenko equation, with examples (KdV equation, Sine-Gordon model). Prepared for the Durham Young Researchers Integrability School, organised by the GATIS network. This is part of a collection of lecture notes.

  8. New simulation approach using classical formalism to water nuclear magnetic relaxation dispersions in presence of superparamagnetic particles used as MRI contrast agents

    Science.gov (United States)

    Vuong, Q. L.; Gossuin, Y.; Gillis, P.; Delangre, S.

    2012-09-01

    Superparamagnetic nanoparticles are used as negative contrast agents in magnetic resonance imaging: owing to their large magnetic moment the water proton spins are dephased, which accelerates the nuclear magnetic relaxation of an aqueous sample containing these particles. Transverse and longitudinal relaxation times depend on several parameters of the nanoparticles such as radius and magnetization and on experimental parameters such as the static magnetic field or echo time. In this work, we introduce a new simulation methodology, using a classical formalism, allowing the simulation of the NMR signal during transverse and longitudinal relaxation induced by superparamagnetic particles in an aqueous solution, which, to our knowledge has never been done before. Nuclear magnetic relaxation dispersion profiles are obtained for a wide range of nanoparticle radii and magnetizations. The results can be classified in two regimes—the well-known motional averaging and static regimes. This generalizes previous studies focusing on transverse relaxation at high magnetic field (larger than 1 T). Simulation results correspond to analytical theories in their validity range and so far unknown dependences of the relaxation with magnetization and radii of the NMR dispersions profiles are observed, which could be used to characterize experimental samples containing large superparamagnetic particles.

  9. Rough sets: the classical and extended views

    Institute of Scientific and Technical Information of China (English)

    ZIARKO Wojciech

    2008-01-01

    The article is a comprehensive review of two major approaches to rough set theory: the classic rough setmodel introduced by Pawlak and the probabilistic approaches. The classic model is presented as a staging ground to the discussion of two varieties of the probabilistic approach, i.e. of the variable precision and Bayesian rough set models. Both of these models extend the classic model to deal with stochastic interactions while preserving the basicideas of the original rough set theory, such as set approximations, data dependencies, reducts etc. The probabilistic models are able to handle weaker data interactions than the classic model, thus extending the applicability of the rough set paradigm. The extended models are presented in considerable detail with some illustrative examples.

  10. A semi-classical approach to the nuclear delta self-energy. Application to the spin-isospin response function problem

    International Nuclear Information System (INIS)

    The delta self-energy is an essential key to the understanding of a great amount of nuclear reactions in the resonance region (pion-nucleus, photon-nucleus, charge exchange...). The self-energy is not observable but, for example, pion or photon absorption enhance phenomena issued from delta deexcitation. The main result of this work is to show that semiclassical method to the Thomas-Fermi order can provide a particularly simple and precise approach of this quantity. In order to illustrate the effects of the self-energy correction, a semiclassical approach of the nuclear spin-isospin response function in the delta resonance region, is also presented

  11. Grassmannians of classical buildings

    CERN Document Server

    Pankov, Mark

    2010-01-01

    Buildings are combinatorial constructions successfully exploited to study groups of various types. The vertex set of a building can be naturally decomposed into subsets called Grassmannians. The book contains both classical and more recent results on Grassmannians of buildings of classical types. It gives a modern interpretation of some classical results from the geometry of linear groups. The presented methods are applied to some geometric constructions non-related to buildings - Grassmannians of infinite-dimensional vector spaces and the sets of conjugate linear involutions. The book is self

  12. Davidson and classical pragmatism

    Directory of Open Access Journals (Sweden)

    Paula Rossi

    2007-06-01

    Full Text Available In this paper I wish to trace some connections between Donald Davidson's work (1917-2003 and two major representatives of the classical pragmatist movement: Charles S. Peirce (1839-1914 and William James (1842-1910. I will start with a basic characterization of classical pragmatism; then, I shall examine certain conceptions in Peirce's and James' pragmatism, in order to establish affinities with Davidson´s thought. Finally, and bearing in mind the previous con-nections, I will reflect briefly on the relevance –often unrecognized- of classical pragmatist ideas in the context of contemporary philosophi-cal discussions.

  13. Classical databases and knowledge organization

    DEFF Research Database (Denmark)

    Hjørland, Birger

    2015-01-01

    ) in the design and use of classical databases. An underlying issue is the kind of retrieval system for which one should aim. Warner’s (2010) differentiation between the computer science traditions and an older library-oriented tradition seems important; the former aim to transform queries......This paper considers classical bibliographic databases based on the Boolean retrieval model (such as MEDLINE and PsycInfo). This model is challenged by modern search engines and information retrieval (IR) researchers, who often consider Boolean retrieval a less efficient approach. The paper...... examines this claim and argues for the continued value of Boolean systems, which suggests two further considerations: (1) the important role of human expertise in searching (expert searchers and “information literate” users) and (2) the role of library and information science and knowledge organization (KO...

  14. Injuries in classical ballet.

    Science.gov (United States)

    Quirk, R

    1984-11-01

    The specialised medical knowledge about dancers' injuries is negligible compared with that which surrounds sports medicine. The author discusses his experience in the management of more than 2000 injuries sustained by dancers of classical ballet. PMID:6151832

  15. Classical and Quantum Intertwine

    OpenAIRE

    Blanchard, Ph.; Jadczyk, A.

    1993-01-01

    Model interactions between classical and quantum systems are briefly discussed. These include: general measurement-like couplings, Stern-Gerlach experiment, model of a counter, quantum Zeno effect, SQUID-tank model.

  16. Interaction between classical and quantum systems

    International Nuclear Information System (INIS)

    An unconventional approach to the measurement problem in quantum mechanics is considered--the apparatus is treated as a classical system, belonging to the macro-world. In order to have a measurement the apparatus must interact with the quantum system. As a first step, the classical apparatus is embedded into a large quantum mechanical structure, making use of a superselection principle. The apparatus and system are coupled such that the apparatus remains classical (principle of integrity), and unambiguous information of the values of a quantum observable are transferred to the variables of the apparatus. Further measurement of the classical apparatus can be done, causing no problems of principle. Thus interactions causing pointers to move (which are not treated) can be added. The restrictions placed by the principle of integrity on the form of the interaction between classical and quantum systems are examined and illustration is given by means of a simple example in which one sees the principle of integrity at work

  17. Archaeological, art-historical, and artistic approaches to classical antiquity. Viccy Coltman (ed.), Making Sense of Greek Art, University of Exeter Press, 2012

    OpenAIRE

    Mattusch, Carol C.

    2012-01-01

    Making sense of Greek Art is a Festschrift in memory of John Betts containing papers by ten of his students and colleagues. Their papers on Greek, Etruscan, Roman, and nineteenth-century topics reveal a wide range of methodologies. Two papers focus on subjects that might be covered in a course on Greek art and archaeology: one evaluates votive offerings in the sanctuary of Artemis Orthia at Sparta (Nicki Waugh); and the other compares archaeological and art-historical approaches to the study...

  18. Classical confined particles

    Science.gov (United States)

    Horzela, Andrzej; Kapuscik, Edward

    1993-01-01

    An alternative picture of classical many body mechanics is proposed. In this picture particles possess individual kinematics but are deprived from individual dynamics. Dynamics exists only for the many particle system as a whole. The theory is complete and allows to determine the trajectories of each particle. It is proposed to use our picture as a classical prototype for a realistic theory of confined particles.

  19. Davidson and classical pragmatism

    OpenAIRE

    Paula Rossi

    2007-01-01

    In this paper I wish to trace some connections between Donald Davidson's work (1917-2003) and two major representatives of the classical pragmatist movement: Charles S. Peirce (1839-1914) and William James (1842-1910). I will start with a basic characterization of classical pragmatism; then, I shall examine certain conceptions in Peirce's and James' pragmatism, in order to establish affinities with Davidson´s thought. Finally, and bearing in mind the previous con-nections, I will reflect brie...

  20. Review. Assessing uncertainty and risk in forest planning and decision support systems: review of classical methods and introduction of new approaches

    Directory of Open Access Journals (Sweden)

    M. Pasalodos-Tato

    2013-07-01

    Full Text Available Aim: Since forest planning is characterized by long time horizon and it typically involves large areas of land and numerous stakeholders, uncertainty and risk should play an important role when developing forest management plans. The aim of this study is to review different methods to deal with risk and uncertainty in forest planning, listing problems that forest managers may face during the preparation of management plans and trying to give recommendations in regard to the application of each method according to the problem case. The inclusion of risk and uncertainty in decision support systems is also analyzed.Area: It covers the temporal and spatial scale of forest planning, the spatial context, the participation process, the objectives dimensions and the good and services addressed.Material and methods: Several hundreds of articles dealing with uncertainty and risk were identified regarding different forestry-related topics and approaches. Form them, around 170 articles were further reviewed, categorized and evaluated.Main results: The study presents a thorough review and classification of methods and approaches to consider risk and uncertainty in forest planning. Moreover, new approaches are introduced, showing the opportunities that their application present in forest planning.Research highlights: The study can aid forest managers in the decision making process when designing a forest management plan considering risk and uncertainty.Keywords: operations research; optimal alternative; stochastic risk; endogenous risk; stand level; forest level.

  1. The Possibility of Reconciling Quantum Mechanics with Classical Probability Theory

    OpenAIRE

    Slavnov, D. A.

    2007-01-01

    We describe a scheme for constructing quantum mechanics in which a quantum system is considered as a collection of open classical subsystems. This allows using the formal classical logic and classical probability theory in quantum mechanics. Our approach nevertheless allows completely reproducing the standard mathematical formalism of quantum mechanics and identifying its applicability limits. We especially attend to the quantum state reduction problem.

  2. A Classical Introduction to Galois Theory

    CERN Document Server

    Newman, Stephen C

    2012-01-01

    This book provides an introduction to Galois theory and focuses on one central theme - the solvability of polynomials by radicals. Both classical and modern approaches to the subject are described in turn in order to have the former (which is relatively concrete and computational) provide motivation for the latter (which can be quite abstract). The theme of the book is historically the reason that Galois theory was created, and it continues to provide a platform for exploring both classical and modern concepts. This book examines a number of problems arising in the area of classical mathematic

  3. Introduction to tomography, classical and quantum

    International Nuclear Information System (INIS)

    The tomographic approach to identify quantum states with fair probability distributions as alternatives to wave functions or density operators is reviewed. The tomographic-probability representation is shown also for classical states. The star-product formalism of quantizers and dequantizers associated with the tomographic picture of classical and quantum mechanics is presented and some kernels of star products are given in explicit forms. The inequalities for Shannon and Rényi entropies determined by tomographic-probability distributions are discussed.

  4. Fertility preservation in female classic galactosemia patients

    OpenAIRE

    van Erven, Britt; Gubbels, Cynthia S.; van Golde, Ron J; Dunselman, Gerard A; Derhaag, Josien G; de Wert, Guido; Geraedts, Joep P; Bosch, Annet M; Treacy, Eileen P; Corrine K Welt; Gerard T. Berry; Rubio-Gozalbo, M. Estela

    2013-01-01

    Almost every female classic galactosemia patient develops primary ovarian insufficiency (POI) as a diet-independent complication of the disease. This is a major concern for patients and their parents, and physicians are often asked about possible options to preserve fertility. Unfortunately, there are no recommendations on fertility preservation in this group. The unique pathophysiology of classic galactosemia with a severely reduced follicle pool at an early age requires an adjusted approach...

  5. Classical geometry Euclidean, transformational, inversive, and projective

    CERN Document Server

    Leonard, I E; Liu, A C F; Tokarsky, G W

    2014-01-01

    Features the classical themes of geometry with plentiful applications in mathematics, education, engineering, and science Accessible and reader-friendly, Classical Geometry: Euclidean, Transformational, Inversive, and Projective introduces readers to a valuable discipline that is crucial to understanding bothspatial relationships and logical reasoning. Focusing on the development of geometric intuitionwhile avoiding the axiomatic method, a problem solving approach is encouraged throughout. The book is strategically divided into three sections: Part One focuses on Euclidean geometry, which p

  6. Introducing a Classical Einstein-Langevin Equation: Proposing a theory for Classical Stochastic Gravity

    CERN Document Server

    Satin, Seema

    2015-01-01

    We attempt to introduce an new approach towards study of certain interesting issues in classical gravity. This can be done for few confined, but interesting and meaningful physical situations, which can be modeled by a classical stochastic Einstein equation. The Einstein equation can be looked upon as an equation of motion, while introducing to it a classical stochastic source or classical fluctuations as driving source. This is analogous to the Langevin equation formalism, in Brownian motion studies. A justification for the validity of such an ansatz for classical gravity is given. The regime of validity of such an approach and the consequences and possible outcomes of this formulation are discussed. We also mention, further relevant directions and applications of the same,that act as motivation towards the new proposal. This field of study can be seen to emerge out of well established ideas and results in Brownian motion theory as well as the Stochastic Semiclassical Gravity (which is already an active area...

  7. Classically-Controlled Quantum Computation

    OpenAIRE

    Perdrix, Simon; Jorrand, Philippe

    2004-01-01

    Quantum computations usually take place under the control of the classical world. We introduce a Classically-controlled Quantum Turing Machine (CQTM) which is a Turing Machine (TM) with a quantum tape for acting on quantum data, and a classical transition function for a formalized classical control. In CQTM, unitary transformations and measurements are allowed. We show that any classical TM is simulated by a CQTM without loss of efficiency. The gap between classical and quantum computations, ...

  8. Low-energy cross-section calculations of single molecules by electron impact: a classical Monte Carlo transport approach with quantum mechanical description

    International Nuclear Information System (INIS)

    The present state of modeling radio-induced effects at the cellular level does not account for the microscopic inhomogeneity of the nucleus from the non-aqueous contents (i.e. proteins, DNA) by approximating the entire cellular nucleus as a homogenous medium of water. Charged particle track-structure calculations utilizing this approximation are therefore neglecting to account for approximately 30% of the molecular variation within the nucleus. To truly understand what happens when biological matter is irradiated, charged particle track-structure calculations need detailed knowledge of the secondary electron cascade, resulting from interactions with not only the primary biological component—water-–but also the non-aqueous contents, down to very low energies. This paper presents our work on a generic approach for calculating low-energy interaction cross-sections between incident charged particles and individual molecules. The purpose of our work is to develop a self-consistent computational method for predicting molecule-specific interaction cross-sections, such as the component molecules of DNA and proteins (i.e. nucleotides and amino acids), in the very low-energy regime. These results would then be applied in a track-structure code and thereby reduce the homogenous water approximation. The present methodology—inspired by seeking a combination of the accuracy of quantum mechanics and the scalability, robustness, and flexibility of Monte Carlo methods—begins with the calculation of a solution to the many-body Schrödinger equation and proceeds to use Monte Carlo methods to calculate the perturbations in the internal electron field to determine the interaction processes, such as ionization and excitation. As a test of our model, the approach is applied to a water molecule in the same method as it would be applied to a nucleotide or amino acid and compared with the low-energy cross-sections from the GEANT4-DNA physics package of the Geant4 simulation toolkit

  9. Low-energy cross-section calculations of single molecules by electron impact: a classical Monte Carlo transport approach with quantum mechanical description

    Science.gov (United States)

    Madsen, J. R.; Akabani, G.

    2014-05-01

    The present state of modeling radio-induced effects at the cellular level does not account for the microscopic inhomogeneity of the nucleus from the non-aqueous contents (i.e. proteins, DNA) by approximating the entire cellular nucleus as a homogenous medium of water. Charged particle track-structure calculations utilizing this approximation are therefore neglecting to account for approximately 30% of the molecular variation within the nucleus. To truly understand what happens when biological matter is irradiated, charged particle track-structure calculations need detailed knowledge of the secondary electron cascade, resulting from interactions with not only the primary biological component—water--but also the non-aqueous contents, down to very low energies. This paper presents our work on a generic approach for calculating low-energy interaction cross-sections between incident charged particles and individual molecules. The purpose of our work is to develop a self-consistent computational method for predicting molecule-specific interaction cross-sections, such as the component molecules of DNA and proteins (i.e. nucleotides and amino acids), in the very low-energy regime. These results would then be applied in a track-structure code and thereby reduce the homogenous water approximation. The present methodology—inspired by seeking a combination of the accuracy of quantum mechanics and the scalability, robustness, and flexibility of Monte Carlo methods—begins with the calculation of a solution to the many-body Schrödinger equation and proceeds to use Monte Carlo methods to calculate the perturbations in the internal electron field to determine the interaction processes, such as ionization and excitation. As a test of our model, the approach is applied to a water molecule in the same method as it would be applied to a nucleotide or amino acid and compared with the low-energy cross-sections from the GEANT4-DNA physics package of the Geant4 simulation toolkit

  10. A novel cell-permeable, selective, and noncompetitive inhibitor of KAT3 histone acetyltransferases from a combined molecular pruning/classical isosterism approach.

    Science.gov (United States)

    Milite, Ciro; Feoli, Alessandra; Sasaki, Kazuki; La Pietra, Valeria; Balzano, Amodio Luca; Marinelli, Luciana; Mai, Antonello; Novellino, Ettore; Castellano, Sabrina; Tosco, Alessandra; Sbardella, Gianluca

    2015-03-26

    Selective inhibitors of the two paralogue KAT3 acetyltransferases (CBP and p300) may serve not only as precious chemical tools to investigate the role of these enzymes in physiopathological mechanisms but also as lead structures for the development of further antitumor agents. After the application of a molecular pruning approach to the hardly optimizable and not very cell-permeable garcinol core structure, we prepared many analogues that were screened for their inhibitory effects using biochemical and biophysical (SPR) assays. Further optimization led to the discovery of the benzylidenebarbituric acid derivative 7h (EML425) as a potent and selective reversible inhibitor of CBP/p300, noncompetitive versus both acetyl-CoA and a histone H3 peptide, and endowed with good cell permeability. Furthermore, in human leukemia U937 cells, it induced a marked and time-dependent reduction in the acetylation of lysine H4K5 and H3K9, a marked arrest in the G0/G1 phase and a significant increase in the hypodiploid nuclei percentage. PMID:25730130

  11. Learning Classical Music Club

    CERN Multimedia

    Learning Classical Music Club

    2010-01-01

    There is a new CERN Club called “Learning Classical Music at CERN”. We are aiming to give classical music lessons for different instruments (see link) for students from 5 to 100 years old. We are now ready to start our activities in the CERN barracks. We are now in the enrollment phase and hope to start lessons very soon ! Club info can be found in the list of CERN Club: http://user.web.cern.ch/user/Communication/SocialLifeActivities/Clubs/Clubs.html Salvatore Buontempo Club President

  12. A Single Classical Quark

    CERN Document Server

    Dzhunushaliev, V D

    1997-01-01

    The spherically symmetric solution in classical SU(3) Yang - Mills theory is found. It is supposed that such solution describes a classical quark. It is regular in origin and hence the interaction between two quarks is small on the small distance. The obtained solution has the singularity on infinity. It is possible that is the reason why the free quark cannot exist. Evidently, nonlocality of this object leads to the fact that in quantum chromodynamic the difficulties arise connected with investigation of quarks interaction on large distance.

  13. Classical Holographic Codes

    CERN Document Server

    Brehm, Enrico M

    2016-01-01

    In this work, we introduce classical holographic codes. These can be understood as concatenated probabilistic codes and can be represented as networks uniformly covering hyperbolic space. In particular, classical holographic codes can be interpreted as maps from bulk degrees of freedom to boundary degrees of freedom. Interestingly, they are shown to exhibit features similar to those expected from the AdS/CFT correspondence. Among these are a version of the Ryu-Takayanagi formula and intriguing properties regarding bulk reconstruction and boundary representations of bulk operations. We discuss the relation of our findings with expectations from AdS/CFT and, in particular, with recent results from quantum error correction.

  14. Classical mechanics with Maxima

    CERN Document Server

    Timberlake, Todd Keene

    2016-01-01

    This book guides undergraduate students in the use of Maxima—a computer algebra system—in solving problems in classical mechanics. It functions well as a supplement to a typical classical mechanics textbook. When it comes to problems that are too difficult to solve by hand, computer algebra systems that can perform symbolic mathematical manipulations are a valuable tool. Maxima is particularly attractive in that it is open-source, multiple-platform software that students can download and install free of charge. Lessons learned and capabilities developed using Maxima are easily transferred to other, proprietary software.

  15. Elementary classical hydrodynamics

    CERN Document Server

    Chirgwin, B H; Langford, W J; Maxwell, E A; Plumpton, C

    1967-01-01

    Elementary Classical Hydrodynamics deals with the fundamental principles of elementary classical hydrodynamics, with emphasis on the mechanics of inviscid fluids. Topics covered by this book include direct use of the equations of hydrodynamics, potential flows, two-dimensional fluid motion, waves in liquids, and compressible flows. Some general theorems such as Bernoulli's equation are also considered. This book is comprised of six chapters and begins by introducing the reader to the fundamental principles of fluid hydrodynamics, with emphasis on ways of studying the motion of a fluid. Basic c

  16. Classic Problems of Probability

    CERN Document Server

    Gorroochurn, Prakash

    2012-01-01

    "A great book, one that I will certainly add to my personal library."—Paul J. Nahin, Professor Emeritus of Electrical Engineering, University of New Hampshire Classic Problems of Probability presents a lively account of the most intriguing aspects of statistics. The book features a large collection of more than thirty classic probability problems which have been carefully selected for their interesting history, the way they have shaped the field, and their counterintuitive nature. From Cardano's 1564 Games of Chance to Jacob Bernoulli's 1713 Golden Theorem to Parrondo's 1996 Perplexin

  17. The classical nova outburst

    International Nuclear Information System (INIS)

    The classical nova outburst occurs on the white dwarf component in a close binary system. Nova systems are members of the general class of cataclysmic variables and other members of the class are the Dwarf Novae, AM Her variables, Intermediate Polars, Recurrent Novae, and some of the Symbiotic variables. Although multiwavelength observations have already provided important information about all of these systems, in this review I will concentrate on the outbursts of the classical and recurrent novae and refer to other members of the class only when necessary. 140 refs., 1 tab

  18. Quasi-classical alternatives in quantum chemistry

    CERN Document Server

    Gineityte, V

    2014-01-01

    The article contains an overview of authors achievements in development of alternative quantum-chemical approaches oriented towards revival of the classical tradition of qualitative chemical thinking instead of obtaining numerical results. The above-mentioned tradition is concluded to be based mainly on principles (rules) of additivity, transferability and locality of molecular properties. Accordingly, model Hamiltonian matrices are used in the approaches under development (called quasi-classical alternatives), wherein algebraic parameters play the role of matrix elements and these are assumed to be transferable for similar atoms and/or atomic orbitals in addition. Further, passing to delocalized descriptions of electronic structures (as usual) is expected to be the main origin of difficulties seeking to formulate quasi-classical alternatives. In the framework of the canonical method of molecular orbitals (MOs), delocalization is shown to be partially avoidable by invoking a recently-suggested approach to sec...

  19. Nuclear motion is classical

    CERN Document Server

    Frank, Irmgard

    2016-01-01

    The notion from ab-initio molecular dynamics simulations that nuclear motion is best described by classical Newton dynamics instead of the time-dependent Schr{\\"o}dinger equation is substantiated. In principle a single experiment should bring clarity. Caution is however necessary, as temperature dependent effects must be eliminated when trying to determine the existence of a zero-point energy.

  20. Strong Coupling and Classicalization

    CERN Document Server

    Dvali, Gia

    2016-01-01

    Classicalization is a phenomenon in which a theory prevents itself from entering into a strong-coupling regime, by redistributing the energy among many weakly-interacting soft quanta. In this way, the scattering process of some initial hard quanta splits into a large number of soft elementary processes. In short, the theory trades the strong coupling for a high-multiplicity of quanta. At very high energies, the outcome of such a scattering experiment is a production of soft states of high occupation number that are approximately classical. It is evident that black hole creation in particle collision at super-Planckian energies is a result of classicalization, but there is no a priory reason why this phenomenon must be limited to gravity. If the hierarchy problem is solved by classicalization, the LHC has a chance of detecting a tower of new resonances. The lowest-lying resonances must appear right at the strong coupling scale in form of short-lived elementary particles. The heavier members of the tower must b...

  1. Classical Iterative Methods

    Czech Academy of Sciences Publication Activity Database

    Axelsson, Owe

    1. Berlin, Heidelberg: Springer-Verlag, 2013 - (Björm, E.), s. 205-224 ISBN 978-3-540-70528-4 Institutional support: RVO:68145535 Keywords : classical iterative methods * applied computational mathematics * encyclopedia Subject RIV: BA - General Mathematics http://www.springerreference.com/docs/ navigation .do?m=Encyclopedia+of+Applied+and+Computational+Mathematics+%28Mathematics+and+Statistics%29-book224

  2. Classical and quantum satisfiability

    CERN Document Server

    de Araújo, Anderson; 10.4204/EPTCS.81.6

    2012-01-01

    We present the linear algebraic definition of QSAT and propose a direct logical characterization of such a definition. We then prove that this logical version of QSAT is not an extension of classical satisfiability problem (SAT). This shows that QSAT does not allow a direct comparison between the complexity classes NP and QMA, for which SAT and QSAT are respectively complete.

  3. Why Study Classical Languages?

    Science.gov (United States)

    Lieberman, Samuel

    This speech emphasizes the significance of living literatures and living cultures which owe a direct debt to the Romans and the Greeks from whom they can trace their origins. After commenting on typical rejoinders to the question "Why study classical languages?" and poking fun at those who advance jaded, esoteric responses, the author dispels the…

  4. Classics in What Sense?

    Science.gov (United States)

    Camic, Charles

    2008-01-01

    They seem the perfect bookends for the social psychologist's collection of "classics" of the field. Two volumes, nearly identical in shape and weight and exactly a century old in 2008--each professing to usher "social psychology" into the world as they both place the hybrid expression square in their titles but then proceed to stake out the field…

  5. Mecanica Clasica (Classical Mechanics)

    OpenAIRE

    Rosu, H. C.

    1999-01-01

    First Internet graduate course on Classical Mechanics in Spanish (Castellano). This is about 80% of the material I covered during the January-June 1999 semester at IFUG in the Mexican city of Leon. English and Romanian versions are in (slow) progress and hopefully will be arXived. For a similar course on Quantum Mechanics, see physics/9808031

  6. Classical galactosaemia revisited

    NARCIS (Netherlands)

    A.M. Bosch

    2006-01-01

    Classical galactosaemia (McKusick 230400) is an: autosomal recessive disorder of galactose metabolism, caused by a deficiency of the enzyme galactose-1-phosphate uridyltransferase (GALT; EC 2.7.712). Most patients present in the neonatal period, after ingestion of galactose, with jaundice, hepatospl

  7. Classical Mythology. Fourth Edition.

    Science.gov (United States)

    Morford, Mark P. O.; Lenardon, Robert J.

    Designed for students with little or no background in classical literature, this book introduces the Greek and Roman myths of creation, myths of the gods, Greek sagas and local legends, and presents contemporary theories about the myths. Drawing on Homer, Hesiod, Pindar, Vergil, and others, the book provides many translations and paraphrases of…

  8. Classicism and Romanticism.

    Science.gov (United States)

    Huddleston, Gregory H.

    1993-01-01

    Describes one teacher's methods for introducing to secondary English students the concepts of Classicism and Romanticism in relation to pictures of gardens, architecture, music, and literary works. Outlines how the unit leads to a writing assignment based on collected responses over time. (HB)

  9. Mecanica Clasica (Classical Mechanics)

    CERN Document Server

    Rosu, H C

    1999-01-01

    First Internet undergraduate course on Classical Mechanics in Spanish (Castellano). This is about 80% of the material I covered during the January-June 1999 semester at IFUG in the Mexican city of Leon. English and Romanian versions are in (slow) progress and hopefully will be arXived. For a similar course on Quantum Mechanics, see physics/9808031

  10. Classical electromagnetic radiation

    CERN Document Server

    Heald, Mark A

    2012-01-01

    Newly corrected, this highly acclaimed text is suitable for advanced physics courses. The author presents a very accessible macroscopic view of classical electromagnetics that emphasizes integrating electromagnetic theory with physical optics. The survey follows the historical development of physics, culminating in the use of four-vector relativity to fully integrate electricity with magnetism.

  11. The Classical Cake Problem

    Science.gov (United States)

    Nelson, Norman N.; Fisch, Forest N.

    1973-01-01

    Discussed are techniques of presentation and solution of the Classical Cake Problem. A frosted cake with a square base is to be cut into n pieces with the volume of cake and frosting the same for each piece. Needed are minimal geometric concepts and the formula for the volume of a prism. (JP)

  12. Semi-classical quantization of chaotic billiards

    International Nuclear Information System (INIS)

    The semi-classical quantization of chaotic billiards will be developed using scattering theory approach. This will be used to introduce and explain the inherent difficulties in the semi-classical quantization of chaos, and to show some of the modern tools which were developed recently to overcome these difficulties. To this end, we shall first obtain a semi-classical secular equation which is based on a finite number of classical periodic orbits. We shall use it to derive some spectral properties, and in particular to investigate the relationship between spectral statistics of quantum chaotic systems and the predictions of random-matrix theory. We shall finally discuss an important family of chaotic billiard, whose statistics does not follow any of the canonical ensembles, (GOE,GUE,...) but rather, corresponds to a new universality class. (author)

  13. Quantization of soluble classical constrained systems

    Energy Technology Data Exchange (ETDEWEB)

    Belhadi, Z. [Laboratoire de physique et chimie quantique, Faculté des sciences, Université Mouloud Mammeri, BP 17, 15000 Tizi Ouzou (Algeria); Laboratoire de physique théorique, Faculté des sciences exactes, Université de Bejaia, 06000 Bejaia (Algeria); Menas, F. [Laboratoire de physique et chimie quantique, Faculté des sciences, Université Mouloud Mammeri, BP 17, 15000 Tizi Ouzou (Algeria); Ecole Nationale Préparatoire aux Etudes d’ingéniorat, Laboratoire de physique, RN 5 Rouiba, Alger (Algeria); Bérard, A. [Equipe BioPhysStat, Laboratoire LCP-A2MC, ICPMB, IF CNRS No 2843, Université de Lorraine, 1 Bd Arago, 57078 Metz Cedex (France); Mohrbach, H., E-mail: herve.mohrbach@univ-lorraine.fr [Equipe BioPhysStat, Laboratoire LCP-A2MC, ICPMB, IF CNRS No 2843, Université de Lorraine, 1 Bd Arago, 57078 Metz Cedex (France)

    2014-12-15

    The derivation of the brackets among coordinates and momenta for classical constrained systems is a necessary step toward their quantization. Here we present a new approach for the determination of the classical brackets which does neither require Dirac’s formalism nor the symplectic method of Faddeev and Jackiw. This approach is based on the computation of the brackets between the constants of integration of the exact solutions of the equations of motion. From them all brackets of the dynamical variables of the system can be deduced in a straightforward way.

  14. Beam structures classical and advanced theories

    CERN Document Server

    Carrera, Erasmo; Petrolo, Marco

    2011-01-01

    Beam theories are exploited worldwide to analyze civil, mechanical, automotive, and aerospace structures. Many beam approaches have been proposed during the last centuries by eminent scientists such as Euler, Bernoulli, Navier, Timoshenko, Vlasov, etc.  Most of these models are problem dependent: they provide reliable results for a given problem, for instance a given section and cannot be applied to a different one. Beam Structures: Classical and Advanced Theories proposes a new original unified approach to beam theory that includes practically all classical and advanced models for be

  15. Quantum emulation of classical dynamics

    OpenAIRE

    Margolus, Norman

    2011-01-01

    In statistical mechanics, it is well known that finite-state classical lattice models can be recast as quantum models, with distinct classical configurations identified with orthogonal basis states. This mapping makes classical statistical mechanics on a lattice a special case of quantum statistical mechanics, and classical combinatorial entropy a special case of quantum entropy. In a similar manner, finite-state classical dynamics can be recast as finite-energy quantum dynamics. This mapping...

  16. Classical and statistical thermodynamics

    CERN Document Server

    Rizk, Hanna A

    2016-01-01

    This is a text book of thermodynamics for the student who seeks thorough training in science or engineering. Systematic and thorough treatment of the fundamental principles rather than presenting the large mass of facts has been stressed. The book includes some of the historical and humanistic background of thermodynamics, but without affecting the continuity of the analytical treatment. For a clearer and more profound understanding of thermodynamics this book is highly recommended. In this respect, the author believes that a sound grounding in classical thermodynamics is an essential prerequisite for the understanding of statistical thermodynamics. Such a book comprising the two wide branches of thermodynamics is in fact unprecedented. Being a written work dealing systematically with the two main branches of thermodynamics, namely classical thermodynamics and statistical thermodynamics, together with some important indexes under only one cover, this treatise is so eminently useful.

  17. Computation in Classical Mechanics

    CERN Document Server

    Timberlake, Todd

    2007-01-01

    There is a growing consensus that physics majors need to learn computational skills, but many departments are still devoid of computation in their physics curriculum. Some departments may lack the resources or commitment to create a dedicated course or program in computational physics. One way around this difficulty is to include computation in a standard upper-level physics course. An intermediate classical mechanics course is particularly well suited for including computation. We discuss the ways we have used computation in our classical mechanics courses, focusing on how computational work can improve students' understanding of physics as well as their computational skills. We present examples of computational problems that serve these two purposes. In addition, we provide information about resources for instructors who would like to include computation in their courses.

  18. The classic project

    International Nuclear Information System (INIS)

    Exchange of data and algorithms among accelerator physics programs is difficult because of unnecessary differences in input formats and internal data structures. To alleviate these problems a C++ class library called CLASSIC (Class Library for Accelerator System Simulation and Control) is being developed with the goal to provide standard building blocks for computer programs used in accelerator design. It includes modules for building accelerator lattice structures in computer memory using a standard input language, a graphical user interface, or a programmed algorithm. It also provides simulation algorithms. These can easily be replaced by modules which communicate with the control system of the accelerator. Exchange of both data and algorithm between different programs using the CLASSIC library should present no difficulty

  19. Injuries in classical ballet

    Directory of Open Access Journals (Sweden)

    Adriana Coutinho de Azevedo Guimarães

    2008-06-01

    Full Text Available This study aimed to elucidate what injuries are most likely to occur due to classical ballet practice. The research used national and international bibliography. The bibliography analysis indicated that technical and esthetical demands lead to a practice of non-anatomical movements, causing the ballet dancer to suffer from a number of associated lesions. Most of the injuries are caused by technical mistakes and wrong training. Troubles in children are usually due to trying to force external rotation at hip level and to undue use of point ballet slippers. The commonest lesions are in feet and ankles, followed by knees and hips. The rarest ones are in the upper limbs. These injuries are caused by exercise excess, by repetitions always in the same side and by wrong and early use of point slippers. The study reached the conclusion that incorrect application of classical ballet technique predisposes the dancers to characteristic injuries.

  20. Are superparamagnetic spins classical?

    OpenAIRE

    Garanin, D. A.

    2008-01-01

    Effective giant spins of magnetic nanoparticles are considered classically in the conventional theory of superparamagnetism based on the Landau-Lifshitz-Langevin equation. However, microscopic calculations for a large spin with uniaxial anisotropy, coupled to the lattice via the simplest generic mechanism, show that the results of the conventional theory are not reproduced in the limit S ->\\infty. In particular, the prefactor Gamma_0 in the Arrhenius escape rate over the barrier Gamma =Gamma_...

  1. Injuries in classical ballet

    OpenAIRE

    Adriana Coutinho de Azevedo Guimarães; Joseani Paulini Neves Simas

    2008-01-01

    This study aimed to elucidate what injuries are most likely to occur due to classical ballet practice. The research used national and international bibliography. The bibliography analysis indicated that technical and esthetical demands lead to a practice of non-anatomical movements, causing the ballet dancer to suffer from a number of associated lesions. Most of the injuries are caused by technical mistakes and wrong training. Troubles in children are usually due to trying to force external ...

  2. A Classic's New Charm

    Institute of Scientific and Technical Information of China (English)

    WANG HAIRONG

    2010-01-01

    @@ North Korea's Phibada Opera Troupe arrived in Beijing on May3,bringing with it a Korean opera adapted from China's classic novel A Dream of Red Mansions written by Cao Xueqin(around 1715-63),a great novelist of the Qing Dynasty(1644-1911).The troupe,invited by the Chinese Ministry of Culture,is one of the largest performing groups having visited China in recent years.

  3. Computation in Classical Mechanics

    OpenAIRE

    Timberlake, Todd; Hasbun, Javier E.

    2007-01-01

    There is a growing consensus that physics majors need to learn computational skills, but many departments are still devoid of computation in their physics curriculum. Some departments may lack the resources or commitment to create a dedicated course or program in computational physics. One way around this difficulty is to include computation in a standard upper-level physics course. An intermediate classical mechanics course is particularly well suited for including computation. We discuss th...

  4. Sociology and Classical Liberalism

    OpenAIRE

    KLEIN, Daniel; Stern, Lotta

    2005-01-01

    We advocate the development of a classical-liberal character within professional sociology. The American Sociological Association (ASA) is taken as representative of professional sociology in the United States. We review the ASA’s activities and organizational statements, to show the association’s leftist character. Internal criticism is often very uneasy about leftist domination of the field. We present survey results establishing that, in voting and in policy views, the ASA membership is mo...

  5. Revisiting a Classic

    Science.gov (United States)

    Rogers, Ibram

    2008-01-01

    As a 26-year-old English teacher in 1958, Chinua Achebe had no idea that the book he was writing would become a literary classic, not only in Africa but also throughout the world. He could only try to articulate the feelings he had for his countrymen and women. Achebe had a burning desire to tell the true story of Africa and African humanity. The…

  6. Concepts of classical optics

    CERN Document Server

    Strong, John

    2004-01-01

    An intermediate course in optics, this volume explores both experimental and theoretical concepts, offering practical knowledge of geometrical optics that will enhance students' comprehension of any relevant applied science. Its exposition of the concepts of classical optics is presented with a minimum of mathematical detail but presumes some knowledge of calculus, vectors, and complex numbers.Subjects include light as wave motion; superposition of wave motions; electromagnetic waves; interaction of light and matter; velocities and scattering of light; polarized light and dielectric boundarie

  7. Diffusion of Classical Solitons

    OpenAIRE

    Dziarmaga, J.; Zakrzewski, W.

    1998-01-01

    We study the diffusion and deformation of classical solitons coupled to thermal noise. The diffusion coefficient for kinks in the $\\phi^4$ theory is predicted up to the second order in $kT$. The prediction is verified by numerical simulations. Multiskyrmions in the vector O(3) sigma model are studied within the same formalism. Thermal noise results in a diffusion on the multisoliton collective coordinate space (moduli space). There are entropic forces which tend, for example, to bind pairs of...

  8. Classical and Contemporary Approaches for Moral Development

    Science.gov (United States)

    Cam, Zekeriya; Seydoogullari, Sedef; Cavdar, Duygu; Cok, Figen

    2012-01-01

    Most of the information in the moral development literature depends on Theories of Piaget and Kohlberg. The theoretical contribution by Gilligan and Turiel are not widely known and not much resource is available in Turkish. For this reason introducing and discussing the theories of Gilligan and Turiel and more comprehensive perspective for moral…

  9. Dense matter theory a simple classical approach

    CERN Document Server

    Savic, P

    1998-01-01

    In the sixties,the first author and R.Kasanin have started developing a mean field theory of dense matter.This paper presents a short review of the basic ideas of the theory,and discusses some examples of its applications,which range from DAC experiments to modelling of planetary interiors.

  10. Casimir effect: The classical limit

    International Nuclear Information System (INIS)

    We analyze the high temperature (or classical) limit of the Casimir effect. A useful quantity which arises naturally in our discussion is the 'relative Casimir energy', which we define for a configuration of disjoint conducting boundaries of arbitrary shapes, as the difference of Casimir energies between the given configuration and a configuration with the same boundaries infinitely far apart. Using path integration techniques, we show that the relative Casimir energy vanishes exponentially fast in temperature. This is consistent with a simple physical argument based on Kirchhoff's law. As a result the 'relative Casimir entropy', which we define in an obviously analogous manner, tends, in the classical limit, to a finite asymptotic value which depends only on the geometry of the boundaries. Thus the Casimir force between disjoint pieces of the boundary, in the classical limit, is entropy driven and is governed by a dimensionless number characterizing the geometry of the cavity. Contributions to the Casimir thermodynamical quantities due to each individual connected component of the boundary exhibit logarithmic deviations in temperature from the behavior just described. These logarithmic deviations seem to arise due to our difficulty to separate the Casimir energy (and the other thermodynamical quantities) from the 'electromagnetic' self-energy of each of the connected components of the boundary in a well defined manner. Our approach to the Casimir effect is not to impose sharp boundary conditions on the fluctuating field, but rather take into consideration its interaction with the plasma of 'charge carriers' in the boundary, with the plasma frequency playing the role of a physical UV cutoff. This also allows us to analyze deviations from a perfect conductor behavior

  11. Classical or equilibrium thermodynamics: basic conceptual aspects

    Directory of Open Access Journals (Sweden)

    Luiz Augusto Calvo Tiritan

    2008-08-01

    Full Text Available The Classical or Equilibrium Thermodynamics is one of the most consolidated fields of Physics. It is synthesized by a well-known and self coherent knowledge structure. The essence of the Classical Thermodynamics theoretical structure consists of a set of natural laws that rule the macroscopic physical systems behavior. These laws were formulated based on observations generalizations and are mostly independent of any hypotheses concerning the microscopic nature of the matter. In general, the approaches established for the Classical Thermodynamics follow one of the following alternatives: the historical approach that describes chronologically the evolution of ideas, concepts and facts, and the postulational approach in which postulates are formulated but are not demonstrated a priori but can be confirmed a posteriori. In this work, a brief review of the pre-classical historical approach conceptual evolution is elaborated, from the beginning of the seventeenth century to the middle of the nineteenth century. As for this, the following themes are dealt with in an evolutionary and phenomenological way: heat nature, thermometry, calorimetry, Carnot’s heat engine, heat mechanical equivalent and the first and second laws. The Zeroth law that was formulated afterwards is included in the discussion.

  12. Scale symmetry in classical and quantum mechanics

    CERN Document Server

    Gozzi, E

    2005-01-01

    In this paper we address again the issue of the scale anomaly in quantum mechanical models with inverse square potential. In particular we examine the interplay between the classical and quantum aspects of the system using in both cases an operatorial approach.

  13. Neo-classical principles for information integrity

    NARCIS (Netherlands)

    Christiaanse, R.; Hulstijn, J.

    2011-01-01

    Abstract: For inter-organizational systems, integrity of information is crucial: how to make sure that the information represented in a system will continue to faithfully represent business reality? In this paper we present a neo-classical approach to information integrity. We apply „classic‟ princi

  14. Molecular Study of nifH1, nifH2, nifH3, nifU, nifV, VF Genes and Classical Approach Cared out to Identification of Azotobacter chrococcum from Soil

    Directory of Open Access Journals (Sweden)

    Adel Kamal Khider

    2012-09-01

    Full Text Available The present study aimed to compare classical approach with molecular based method for identification of Azotobacter chrococcum from soil samples. A. chrococcum was isolated from soil source in Erbil city, Iraq. They were cultivated under laboratory conditions using Nitrogen free Azotobacter specific medium. A. chrococcum was present in all soil samples. result shows that A. chrococcum were rod shape, motility occur through the use of peritrichous flagella, cysts-forming, positive to oxidase, catalase and tryptophanase test, unable to liquefy gelatin, with insoluble brown or brown-black pigmentation and darken with age. Utilized starch, sucrose, mannitol and moloanat, but not rhamnose. molecular method based on detection of nifgenes have been successfully applied to describe A. chrococcum isolated from soil. The PCR products for nifH1 1102bp, nifH2 246bp, nifH3 128bp, nifU 930bp, nifV 1146bp and VF gene 594bp were detected on gel electrophoresis, while no bands observed for negative control. The isolated bacteria considered Azotobacte chrococcum belonging to Genus Azotobacter.

  15. On Classical Ideal Gases

    Directory of Open Access Journals (Sweden)

    Laurent Chusseau

    2013-02-01

    Full Text Available We show that the thermodynamics of ideal gases may be derived solely from the Democritean concept of corpuscles moving in vacuum plus a principle of simplicity, namely that these laws are independent of the laws of motion, aside from the law of energy conservation. Only a single corpuscle in contact with a heat bath submitted to a z and t-invariant force is considered. Most of the end results are known but the method appears to be novel. The mathematics being elementary, the present paper should facilitate the understanding of the ideal gas law and of classical thermodynamics even though not-usually-taught concepts are being introduced.

  16. Mechanics classical and quantum

    CERN Document Server

    Taylor, T T

    2015-01-01

    Mechanics: Classical and Quantum explains the principles of quantum mechanics via the medium of analytical mechanics. The book describes Schrodinger's formulation, the Hamilton-Jacobi equation, and the Lagrangian formulation. The author discusses the Harmonic Oscillator, the generalized coordinates, velocities, as well as the application of the Lagrangian formulation to systems that are partially or entirely electromagnetic in character under certain conditions. The book examines waves on a string under tension, the isothermal cavity radiation, and the Rayleigh-Jeans result pertaining to the e

  17. A Classic Through Eternity

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    FIVE years ago, an ancient Chinese air was beamed to outer space as a PR exercise. To humankind, music is a universal language, so the tune seemed an ideal medium for communication with extraterrestrial intelligence. So far there has been no response, but it is believed that the tune will play for a billion years, and eventually be heard and understood. The melody is called High Mountain and Flowing Stream, and it is played on the guqin, a seven-stringed classical musical instrument similar to the zither.

  18. Introducing Newton and classical physics

    CERN Document Server

    Rankin, William

    2002-01-01

    The rainbow, the moon, a spinning top, a comet, the ebb and flood of the oceans ...a falling apple. There is only one universe and it fell to Isaac Newton to discover its secrets. Newton was arguably the greatest scientific genius of all time, and yet he remains a mysterious figure. Written and illustrated by William Rankin, "Introducting Newton and Classical Physics" explains the extraordinary ideas of a man who sifted through the accumulated knowledge of centuries, tossed out mistaken beliefs, and single-handedly made enormous advances in mathematics, mechanics and optics. By the age of 25, entirely self-taught, he had sketched out a system of the world. Einstein's theories are unthinkable without Newton's founding system. He was also a secret heretic, a mystic and an alchemist, the man of whom Edmund Halley said "Nearer to the gods may no man approach!". This is an ideal companion volume to "Introducing Einstein".

  19. Hydrogen: Beyond the Classic Approximation

    International Nuclear Information System (INIS)

    The classical nucleus approximation is the most frequently used approach for the resolution of problems in condensed matter physics.However, there are systems in nature where it is necessary to introduce the nuclear degrees of freedom to obtain a correct description of the properties.Examples of this, are the systems with containing hydrogen.In this work, we have studied the resolution of the quantum nuclear problem for the particular case of the water molecule.The Hartree approximation has been used, i.e. we have considered that the nuclei are distinguishable particles.In addition, we have proposed a model to solve the tunneling process, which involves the resolution of the nuclear problem for configurations of the system away from its equilibrium position

  20. Casimir Effect - The Classical Limit

    International Nuclear Information System (INIS)

    The temperature dependence of the Casimir effect for the radiation field confined between two conducting plates is analysed; The Casimir energy is shown to decline exponentially with temperature while the Casimir entropy which is defined in the text is shown to approach a limit which depends only on the geometry of the constraining plates. The result is shown to hold, for a scalar field, for arbitrary geometry. The high temperature (T) expansion is shown to be ''robust'', i.e. it does not have any nonvanishing correction to the ''classical' result where the latter is defined by the validity of the Rayleigh - Jeans law. We show that validity of the Rayleigh - Jeans law implies the vanishing of the Casimir energy, hence the high temperature Casimir force, for a wide variety of geometries, is purely entropic

  1. Numerical calculation of classical and non-classical electrostatic potentials

    CERN Document Server

    Christensen, D; Neyenhuis, B; Christensen, Dan; Durfee, Dallin S.; Neyenhuis, Brian

    2006-01-01

    We present a numerical exercise in which classical and non-classical electrostatic potentials were calculated. The non-classical fields take into account effects due to a possible non-zero photon rest mass. We show that in the limit of small photon rest mass, both the classical and non-classical potential can be found by solving Poisson's equation twice, using the first calculation as a source term in the second calculation. Our results support the assumptions in a recent proposal to use ion interferometry to search for a non-zero photon rest mass.

  2. Fano Interference in Classical Oscillators

    Science.gov (United States)

    Satpathy, S.; Roy, A.; Mohapatra, A.

    2012-01-01

    We seek to illustrate Fano interference in a classical coupled oscillator by using classical analogues of the atom-laser interaction. We present an analogy between the dressed state picture of coherent atom-laser interaction and a classical coupled oscillator. The Autler-Townes splitting due to the atom-laser interaction is analogous to the…

  3. Decoherence, chaos, the quantum and the classical

    Science.gov (United States)

    Zurek, W. H.; Paz, J. P.

    The key ideas of the environment-induced decoherence approach are reviewed. Application of decoherence to the transition from quantum to classical in open quantum systems with chaotic classical analogs is described. The arrow of time is, in this context, a result of the information loss to the correlations with the environment. The asymptotic rate of entropy production (which is reached quickly, on the dynamical timescale) is independent of the details of the coupling of the quantum system to the environment, and is set by the Lyapunov exponents. We also briefly outline the existential interpretation of quantum mechanics, justifying the slogan, no information without representation.

  4. Evolution of classical projected phase space density in billiards

    Indian Academy of Sciences (India)

    Debabrata Biswas

    2005-04-01

    The classical phase space density projected on to the configuration space offers a means of comparing classical and quantum evolution. In this alternate approach that we adopt here, we show that for billiards, the eigenfunctions of the coarse-grained projected classical evolution operator are identical to a first approximation to the quantum Neumann eigenfunctions. Moreover, there exists a correspondence between the respective eigenvalues although their time evolutions differ.

  5. Mechanical Systems, Classical Models

    CERN Document Server

    Teodorescu, Petre P

    2009-01-01

    This third volume completes the Work Mechanical Systems, Classical Models. The first two volumes dealt with particle dynamics and with discrete and continuous mechanical systems. The present volume studies analytical mechanics. Topics like Lagrangian and Hamiltonian mechanics, the Hamilton-Jacobi method, and a study of systems with separate variables are thoroughly discussed. Also included are variational principles and canonical transformations, integral invariants and exterior differential calculus, and particular attention is given to non-holonomic mechanical systems. The author explains in detail all important aspects of the science of mechanics, regarded as a natural science, and shows how they are useful in understanding important natural phenomena and solving problems of interest in applied and engineering sciences. Professor Teodorescu has spent more than fifty years as a Professor of Mechanics at the University of Bucharest and this book relies on the extensive literature on the subject as well as th...

  6. Grassmannization of classical models

    CERN Document Server

    Pollet, Lode; Prokof'ev, Nikolay V; Svistunov, Boris V

    2016-01-01

    Applying Feynman diagrammatics to non-fermionic strongly correlated models with local constraints might seem generically impossible for two separate reasons: (i) the necessity to have a Gaussian (non-interacting) limit on top of which the perturbative diagrammatic expansion is generated by Wick's theorem, and (ii) the Dyson's collapse argument implying that the expansion in powers of coupling constant is divergent. We show that for arbitrary classical lattice models both problems can be solved/circumvented by reformulating the high-temperature expansion (more generally, any discrete representation of the model) in terms of Grassmann integrals. Discrete variables residing on either links, plaquettes, or sites of the lattice are associated with the Grassmann variables in such a way that the partition function (and correlations) of the original system and its Grassmann-field counterpart are identical. The expansion of the latter around its Gaussian point generates Feynman diagrams. A proof-of-principle implement...

  7. Citation classics in epilepsy

    Directory of Open Access Journals (Sweden)

    Maryann Wilson

    2013-01-01

    Full Text Available BACKGROUND: The impact of a scientific article is proportional to the citations it has received. In this study, we set out to identify the most cited works in epileptology in order to evaluate research trends in this field. METHODS: According to the Web of Science database, articles with more than 400 citations qualify as "citation classics". We conducted a literature search on the ISI Web of Science bibliometric database for scientific articles relevant to epilepsy. RESULTS: We retrieved 67 highly cited articles (400 or more citations, which were published in 31 journals: 17 clinical studies, 42 laboratory studies, 5 reviews and 3 classification articles. Clinical studies consisted of epidemiological analyses (n=3, studies on the clinical phenomenology of epilepsy (n=5 – including behavioral and prognostic aspects – and articles focusing on pharmacological (n=6 and non-pharmacological (n=3 treatment. The laboratory studies dealt with genetics (n=6, animal models (n=27, and neurobiology (n=9 – including both neurophysiology and neuropathology studies. The majority (61% of citation classics on epilepsy were published after 1986, possibly reflecting the expansion of research interest in laboratory studies driven by the development of new methodologies, specifically in the fields of genetics and animal models. Consequently, clinical studies were highly cited both before and after the mid 80s, whilst laboratory researches became widely cited after 1990. CONCLUSIONS: Our study indicates that the main drivers of scientific impact in the field of epileptology have increasingly become genetic and neurobiological studies, along with research on animal models of epilepsy. These articles are able to gain the highest numbers of citations in the time span of a few years and suggest potential directions for future research.

  8. Quantum flesh on classical bones: Semiclassical bridges across the quantum-classical divide

    Energy Technology Data Exchange (ETDEWEB)

    Bokulich, Alisa [Center for Philosophy and History of Science, Boston University, Boston, MA (United States)

    2014-07-01

    Traditionally quantum mechanics is viewed as having made a sharp break from classical mechanics, and the concepts and methods of these two theories are viewed as incommensurable with one another. A closer examination of the history of quantum mechanics, however, reveals that there is a strong sense in which quantum mechanics was built on the backbone of classical mechanics. As a result, there is a considerable structural continuity between these two theories, despite their important differences. These structural continuities provide a ground for semiclassical methods in which classical structures, such as trajectories, are used to investigate and model quantum phenomena. After briefly tracing the history of semiclassical approaches, I show how current research in semiclassical mechanics is revealing new bridges across the quantum-classical divide.

  9. Quantum flesh on classical bones: Semiclassical bridges across the quantum-classical divide

    International Nuclear Information System (INIS)

    Traditionally quantum mechanics is viewed as having made a sharp break from classical mechanics, and the concepts and methods of these two theories are viewed as incommensurable with one another. A closer examination of the history of quantum mechanics, however, reveals that there is a strong sense in which quantum mechanics was built on the backbone of classical mechanics. As a result, there is a considerable structural continuity between these two theories, despite their important differences. These structural continuities provide a ground for semiclassical methods in which classical structures, such as trajectories, are used to investigate and model quantum phenomena. After briefly tracing the history of semiclassical approaches, I show how current research in semiclassical mechanics is revealing new bridges across the quantum-classical divide.

  10. Quantum locking of classical correlations and quantum discord of classical-quantum states

    CERN Document Server

    Boixo, S; Cavalcanti, D; Modi, K; Winter, A

    2011-01-01

    A locking protocol between two parties is as follows: Alice gives an encrypted classical message to Bob which she does not want Bob to be able to read until she gives him the key. If Alice is using classical resources, and she wants to approach unconditional security, then the key and the message must have comparable sizes. But if Alice prepares a quantum state, the size of the key can be comparatively negligible. This effect is called quantum locking. Entanglement does not play a role in this quantum advantage. We show that, in this scenario, the quantum discord quantifies the advantage of the quantum protocol over the corresponding classical one for any classical-quantum state.

  11. Complement dependent cytotoxicity (CDC) activity of a humanized anti Lewis-Y antibody: FACS-based assay versus the 'classical' radioactive method -- qualification, comparison and application of the FACS-based approach.

    Science.gov (United States)

    Nechansky, A; Szolar, O H J; Siegl, P; Zinoecker, I; Halanek, N; Wiederkum, S; Kircheis, R

    2009-05-01

    The fully humanized Lewis-Y carbohydrate specific monoclonal antibody (mAb) IGN311 is currently tested in a passive immunotherapy approach in a clinical phase I trail and therefore regulatory requirements demand qualified assays for product analysis. To demonstrate the functionality of its Fc-region, the capacity of IGN311 to mediate complement dependent cytotoxicity (CDC) against human breast cancer cells was evaluated. The "classical" radioactive method using chromium-51 and a FACS-based assay were established and qualified according to ICH guidelines. Parameters evaluated were specificity, response function, bias, repeatability (intra-day precision), intermediate precision (operator-time different), and linearity (assay range). In the course of a fully nested design, a four-parameter logistic equation was identified as appropriate calibration model for both methods. For the radioactive assay, the bias ranged from -6.1% to -3.6%. The intermediate precision for future means of duplicate measurements revealed values from 12.5% to 15.9% and the total error (beta-expectation tolerance interval) of the method was found to be <40%. For the FACS-based assay, the bias ranged from -8.3% to 0.6% and the intermediate precision for future means of duplicate measurements revealed values from 4.2% to 8.0%. The total error of the method was found to be <25%. The presented data demonstrate that the FACS-based CDC is more accurate than the radioactive assay. Also, the elimination of radioactivity and the 'real-time' counting of apoptotic cells further justifies the implementation of this method which was subsequently applied for testing the influence of storage at 4 degrees C and 25 degrees C ('stability testing') on the potency of IGN311 drug product. The obtained results demonstrate that the qualified functional assay represents a stability indicating test method. PMID:19250790

  12. Classicalization of quantum variables and quantum–classical hybrids

    International Nuclear Information System (INIS)

    The extraction of classical degrees of freedom in quantum mechanics is studied in the stochastic variational method. By using this classicalization, a hybrid model constructed from quantum and classical variables (quantum–classical hybrids) is derived. In this procedure, conservation laws such as energy are maintained, and Ehrenfest's theorem is still satisfied with modification. The criterion for the applicability of quantum–classical hybrids is also discussed. - Highlights: • The new derivation of a quantum–classical hybrid (QCH) model is discussed based on a variational principle. • Any conserved quantities are automatically defined as the invariant transforms of a stochastic action. • The quantitative criterion to determine the validity of QCH is proposed. • Ehrenfest's theorem is satisfied in a modified way

  13. Classical Fourier analysis

    CERN Document Server

    Grafakos, Loukas

    2014-01-01

    The main goal of this text is to present the theoretical foundation of the field of Fourier analysis on Euclidean spaces. It covers classical topics such as interpolation, Fourier series, the Fourier transform, maximal functions, singular integrals, and Littlewood–Paley theory. The primary readership is intended to be graduate students in mathematics with the prerequisite including satisfactory completion of courses in real and complex variables. The coverage of topics and exposition style are designed to leave no gaps in understanding and stimulate further study. This third edition includes new Sections 3.5, 4.4, 4.5 as well as a new chapter on “Weighted Inequalities,” which has been moved from GTM 250, 2nd Edition. Appendices I and B.9 are also new to this edition.  Countless corrections and improvements have been made to the material from the second edition. Additions and improvements include: more examples and applications, new and more relevant hints for the existing exercises, new exercises, and...

  14. Classics in radio astronomy

    CERN Document Server

    Sullivan, Woodruff Turner

    1982-01-01

    Radio techniques were the nrst to lead astronomy away from the quiescent and limited Universe revealed by traditional observations at optical wave­ lengths. In the earliest days of radio astronomy, a handful of radio physicists and engineers made one startling discovery after another as they opened up the radio sky. With this collection of classic papers and the extensive intro­ ductory material, the reader can experience these exciting discoveries, as well as understand the developing techniques and follow the motivations which prompted the various lines of inquiry. For instance he or she will follow in detail the several attempts to detect radio waves from the sun at the turn of the century; the unravelling by Jansky of a "steady hiss type static"; the incredible story of Reber who built a 9 meter dish in his backyard in 1937 and then mapped the Milky Way; the vital discoveries by Hey and colleagues of radio bursts from the Sun and of a discrete source in the constellation of Cygnus; the development of re...

  15. Classical and quantum effective theories

    CERN Document Server

    Polonyi, Janos

    2014-01-01

    A generalization of the action principle of classical mechanics, motivated by the Closed Time Path (CTP) scheme of quantum field theory, is presented to deal with initial condition problems and dissipative forces. The similarities of the classical and the quantum cases are underlined. In particular, effective interactions which describe classical dissipative forces represent the system-environment entanglement. The relation between the traditional effective theories and their CTP extension is briefly discussed and few qualitative examples are mentioned.

  16. Population in the classic economics

    OpenAIRE

    Adnan Doğruyol

    2013-01-01

    Growth subject in economics is an important factor of development. Classic economics ecole indicates the population as main variable which tender of growth. On the other hand T. R. Malthus is known as economist who regards population as a problem and brings up it among the classical economists. However, Adam Smith is an intellectual who discussed population problem earlier on the classic economics theory. According to Adam Smith one of the main factors that realise the growth is labour. In ad...

  17. Coherent Communication of Classical Messages

    OpenAIRE

    Harrow, Aram W.

    2003-01-01

    We define "coherent communication" in terms of a simple primitive, show it is equivalent to the ability to send a classical message with a unitary or isometric operation, and use it to relate other resources in quantum information theory. Using coherent communication, we are able to generalize super-dense coding to prepare arbitrary quantum states instead of only classical messages. We also derive single-letter formulae for the classical and quantum capacities of a bipartite unitary gate assi...

  18. The classic: Bone morphogenetic protein.

    Science.gov (United States)

    Urist, Marshall R; Strates, Basil S

    2009-12-01

    This Classic Article is a reprint of the original work by Marshall R. Urist and Basil S. Strates, Bone Morphogenetic Protein. An accompanying biographical sketch of Marshall R. Urist, MD is available at DOI 10.1007/s11999-009-1067-4; a second Classic Article is available at DOI 10.1007/s11999-009-1069-2; and a third Classic Article is available at DOI 10.1007/s11999-009-1070-9. The Classic Article is copyright 1971 by Sage Publications Inc. Journals and is reprinted with permission from Urist MR, Strates BS. Bone morphogenetic protein. J Dent Res. 1971;50:1392-1406. PMID:19727989

  19. A Classic Beauty

    Science.gov (United States)

    2007-01-01

    M51, whose name comes from being the 51st entry in Charles Messier's catalog, is considered to be one of the classic examples of a spiral galaxy. At a distance of about 30 million light-years from Earth, it is also one of the brightest spirals in the night sky. A composite image of M51, also known as the Whirlpool Galaxy, shows the majesty of its structure in a dramatic new way through several of NASA's orbiting observatories. X-ray data from NASA's Chandra X-ray Observatory reveals point-like sources (purple) that are black holes and neutron stars in binary star systems. Chandra also detects a diffuse glow of hot gas that permeates the space between the stars. Optical data from the Hubble Space Telescope (green) and infrared emission from the Spitzer Space Telescope (red) both highlight long lanes in the spiral arms that consist of stars and gas laced with dust. A view of M51 with the Galaxy Evolution Explorer telescope shows hot, young stars that produce lots of ultraviolet energy (blue). The textbook spiral structure is thought be the result of an interaction M51 is experiencing with its close galactic neighbor, NGC 5195, which is seen just above. Some simulations suggest M51's sharp spiral shape was partially caused when NGC 5195 passed through its main disk about 500 million years ago. This gravitational tug of war may also have triggered an increased level of star formation in M51. The companion galaxy's pull would be inducing extra starbirth by compressing gas, jump-starting the process by which stars form.

  20. Some classical Diophantine equations

    Directory of Open Access Journals (Sweden)

    Nikita Bokarev

    2014-09-01

    Full Text Available An attempt to find common solutions complete some Diophantine equations of the second degree with three variables, traced some patterns, suggest a common approach, which being elementary, however, lead to a solution of such equations. Using arithmetic functions allowed to write down the solutions in a single formula with no restrictions on the parameters used.

  1. Envy and jealousy in Classical Athens

    OpenAIRE

    Sanders, E.M.

    2010-01-01

    Emotions differ between cultures, especially in their eliciting conditions, social acceptability, forms of expression, and co-extent of terminology. This thesis examines the psychological sensation and social expression of envy and jealousy in Classical Athens. Previous scholarship on envy and jealousy (Walcot 1978, Konstan and Rutter 2003) has primarily taken a lexical approach, focusing on usage of the Greek words phthonos (envy, begrudging spite, possessive jealousy) and zêl...

  2. Termogravimetria: um novo enfoque para a clássica determinação de cálcio em cascas de ovos Termogravimetry: a new approach for the classic determination of calcium in eggshells

    Directory of Open Access Journals (Sweden)

    Júnia G. Pereira

    2009-01-01

    Full Text Available The use of thermoanalytical data in sample preparation is described as a tool to catch the students' attention to some details that can simplify both the analysis and the analytical procedure. In this case, the thermal decomposition of eggshells was first investigated by thermogravimetry (TGA. Although the classical procedures suggest long exposure to high temperatures, the TGA data showed that the decomposition of organic matter takes place immediately when the sample is heated up to 800 °C under air atmosphere. After decomposition, the calcium content was determined by flame atomic emission photometry and compared with the results obtained using classical volumetric titration with EDTA.

  3. Classical and quantum information

    CERN Document Server

    Marinescu, Dan C

    2011-01-01

    A new discipline, Quantum Information Science, has emerged in the last two decades of the twentieth century at the intersection of Physics, Mathematics, and Computer Science. Quantum Information Processing is an application of Quantum Information Science which covers the transformation, storage, and transmission of quantum information; it represents a revolutionary approach to information processing. This book covers topics in quantum computing, quantum information theory, and quantum error correction, three important areas of quantum information processing. Quantum information theory an

  4. Classical Music Fan Chen Li

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The heyday of Beijing’s classical music beganin 1993, when top-quality sound equipment andrecords were imported. Also in that year, BeijingMusic Radio presented a classical music programtitled "Fan’s Club" and founded the "Music and

  5. Dynamical Symmetries in Classical Mechanics

    Science.gov (United States)

    Boozer, A. D.

    2012-01-01

    We show how symmetries of a classical dynamical system can be described in terms of operators that act on the state space for the system. We illustrate our results by considering a number of possible symmetries that a classical dynamical system might have, and for each symmetry we give examples of dynamical systems that do and do not possess that…

  6. Breast cancer mortality in mexico: an age-period-cohort analysis Mortalidad por cáncer de mama en méxico: un análisis de edad-periodo-cohorte

    Directory of Open Access Journals (Sweden)

    Francisco Franco-Marina

    2009-01-01

    Full Text Available OBJECTIVE: To assess the age, period and cohort effects on breast cancer (BC mortality in Mexico. MATERIAL AND METHODS: Age, period and cohort curvature trends for BC mortality were estimated through the Poisson Regression model proposed by Holford. RESULTS: Nationally, BC death rates have leveled off since 1995 in most age groups. BC mortality trends are mainly determined by birth cohort and age effects in Mexico. Women born between 1940 and 1955 show the highest rate of increase in BC mortality. Women born afterwards still show an increasing trend but at a much lower rate. Mammography and adjuvant therapy have had a limited impact on mortality. Potential reasons for observed patterns are discussed. An increase in BC mortality in Mexico is expected in the following decades. CONCLUSIONS: Mammography screening programs and timely access to effective treatment should be a national priority to reverse the expected increasing BC mortality trend.OBJETIVO: Evaluar efectos de edad-periodo-cohorte en la mortalidad por cáncer de mama (CaMa en México. MATERIAL Y MÉTODOS: Las tendencias de los efectos de edad-periodo-cohorte fueron estimados mediante un modelo de regresión de Poisson propuesto por Holford. RESULTADOS: Las tasas de mortalidad por CaMa se han estabilizado en la mayoría de los grupos de edad desde 1995 y están determinadas principalmente por efectos de cohorte y edad. Las mujeres nacidas entre 1940 y 1955 muestran los mayores aumentos en la mortalidad en comparación con las nacidas después de este período. La mamografía y la terapia adyuvante han tenido un impacto limitado sobre la mortalidad. Se discuten posibles explicaciones de las tendencias observadas. En las siguientes décadas se espera continúe aumentando la mortalidad por CaMa. CONCLUSIONES: El acceso a mamografía y a tratamiento oportuno y efectivo debieran ser una prioridad para revertir la tendencia creciente esperada de la mortalidad por CM.

  7. Entanglement assisted classical communication simulates "classical communication" without causal order

    OpenAIRE

    Akibue, Seiseki; Owari, Masaki; Kato, Go; Murao, Mio

    2016-01-01

    Phenomena induced by the existence of entanglement, such as nonlocal correlations, exhibit characteristic properties of quantum mechanics distinguishing from classical theories. When entanglement is accompanied by classical communication, it enhances the power of quantum operations jointly performed by two spatially separated parties. Such a power has been analyzed by the gap between the performances of joint quantum operations implementable by local operations at each party connected by clas...

  8. Quantum localization of Classical Mechanics

    CERN Document Server

    Batalin, Igor A

    2016-01-01

    Quantum localization of classical mechanics within the BRST-BFV and BV (or field-antifield) quantization methods are studied. It is shown that a special choice of gauge fixing functions (or BRST-BFV charge) together with the unitary limit leads to Hamiltonian localization in the path integral of the BRST-BFV formalism. In turn, we find that a special choice of gauge fixing functions being proportional to extremals of an initial non-degenerate classical action together with a very special solution of the classical master equation result in Lagrangian localization in the partition function of the BV formalism.

  9. Quantum localization of classical mechanics

    Science.gov (United States)

    Batalin, Igor A.; Lavrov, Peter M.

    2016-07-01

    Quantum localization of classical mechanics within the BRST-BFV and BV (or field-antifield) quantization methods are studied. It is shown that a special choice of gauge fixing functions (or BRST-BFV charge) together with the unitary limit leads to Hamiltonian localization in the path integral of the BRST-BFV formalism. In turn, we find that a special choice of gauge fixing functions being proportional to extremals of an initial non-degenerate classical action together with a very special solution of the classical master equation result in Lagrangian localization in the partition function of the BV formalism.

  10. Classical theory of atomic collisions - The first hundred years

    Science.gov (United States)

    Grujić, Petar V.

    2012-05-01

    Classical calculations of the atomic processes started in 1911 with famous Rutherford's evaluation of the differential cross section for α particles scattered on foil atoms [1]. The success of these calculations was soon overshadowed by the rise of Quantum Mechanics in 1925 and its triumphal success in describing processes at the atomic and subatomic levels. It was generally recognized that the classical approach should be inadequate and it was neglected until 1953, when the famous paper by Gregory Wannier appeared, in which the threshold law for the single ionization cross section behaviour by electron impact was derived. All later calculations and experimental studies confirmed the law derived by purely classical theory. The next step was taken by Ian Percival and collaborators in 60s, who developed a general classical three-body computer code, which was used by many researchers in evaluating various atomic processes like ionization, excitation, detachment, dissociation, etc. Another approach was pursued by Michal Gryzinski from Warsaw, who started a far reaching programme for treating atomic particles and processes as purely classical objects [2]. Though often criticized for overestimating the domain of the classical theory, results of his group were able to match many experimental data. Belgrade group was pursuing the classical approach using both analytical and numerical calculations, studying a number of atomic collisions, in particular near-threshold processes. Riga group, lead by Modris Gailitis [3], contributed considerably to the field, as it was done by Valentin Ostrovsky and coworkers from Sanct Petersbourg, who developed powerful analytical methods within purely classical mechanics [4]. We shall make an overview of these approaches and show some of the remarkable results, which were subsequently confirmed by semiclassical and quantum mechanical calculations, as well as by the experimental evidence. Finally we discuss the theoretical and

  11. Hybrid Quantum-Classical Hierarchy for Mitigation of Decoherence and Determination of Excited States

    CERN Document Server

    McClean, Jarrod R; Carter, Jonathan; de Jong, Wibe A

    2016-01-01

    Using quantum devices supported by classical computational resources is a promising approach to quantum-enabled computation. One example of such a hybrid quantum-classical approach is the variational quantum eigensolver (VQE) built to utilize quantum resources for the solution of eigenvalue problems and optimizations with minimal coherence time requirements by leveraging classical computational resources. These algorithms have been placed among the candidates for first to achieve supremacy over classical computation. Here, we provide evidence for the conjecture that variational approaches can automatically suppress even non-systematic decoherence errors by introducing an exactly solvable channel model of variational state preparation. Moreover, we show how variational quantum-classical approaches fit in a more general hierarchy of measurement and classical computation that allows one to obtain increasingly accurate solutions with additional classical resources. We demonstrate numerically on a sample electroni...

  12. Classical and stochastic Laplacian growth

    CERN Document Server

    Gustafsson, Björn; Vasil’ev, Alexander

    2014-01-01

    This monograph covers a multitude of concepts, results, and research topics originating from a classical moving-boundary problem in two dimensions (idealized Hele-Shaw flows, or classical Laplacian growth), which has strong connections to many exciting modern developments in mathematics and theoretical physics. Of particular interest are the relations between Laplacian growth and the infinite-size limit of ensembles of random matrices with complex eigenvalues; integrable hierarchies of differential equations and their spectral curves; classical and stochastic Löwner evolution and critical phenomena in two-dimensional statistical models; weak solutions of hyperbolic partial differential equations of singular-perturbation type; and resolution of singularities for compact Riemann surfaces with anti-holomorphic involution. The book also provides an abundance of exact classical solutions, many explicit examples of dynamics by conformal mapping as well as a solid foundation of potential theory. An extensive biblio...

  13. New perspectives on classical electromagnetism

    OpenAIRE

    Cote, Paul J.

    2009-01-01

    The fallacies associated with the gauge concept in electromagnetism are illustrated. A clearer and more valid formulation of the basics of classical electromagnetism is provided by recognizing existing physical constraints as well as the physical reality of the vector potential.

  14. Classical Mechanics and Symplectic Integration

    DEFF Research Database (Denmark)

    Nordkvist, Nikolaj; Hjorth, Poul G.

    2005-01-01

    Content: Classical mechanics: Calculus of variations, Lagrange’s equations, Symmetries and Noether’s theorem, Hamilton’s equations, cannonical transformations, integrable systems, pertubation theory. Symplectic integration: Numerical integrators, symplectic integrators, main theorem on symplectic...

  15. Fano interference in classical oscillators

    International Nuclear Information System (INIS)

    We seek to illustrate Fano interference in a classical coupled oscillator by using classical analogues of the atom-laser interaction. We present an analogy between the dressed state picture of coherent atom-laser interaction and a classical coupled oscillator. The Autler-Townes splitting due to the atom-laser interaction is analogous to the splitting of normal-mode frequencies of a coupled oscillator. Using this analogy, we simulate and experimentally demonstrate Fano interference and the associated phenomena in three-level atoms in a coupled electrical resonator circuit. This work aims to highlight analogies between classical and quantum systems for students at the postgraduate and graduate levels. Also, the reported technique can be easily realized in undergraduate laboratories. (paper)

  16. Elementary charges in classical electrodynamics

    OpenAIRE

    KAPU'{S}CIK, Edward

    1999-01-01

    In the framework of classical electrodynamics elementary particles are treated as capacitors. The electrostatic potentials satisfy equations of the Schrödinger type. An interesting "quantization condition" for elementary charges is derived.

  17. Probabilities for classically forbidden transitions using classical and classical path methods

    International Nuclear Information System (INIS)

    Limits are established for the applicability of purely classical methods for calculating nonreactive, inelastic transition probabilities in collinear collisions of a structureless atom and a harmonic oscillator. These limits, obtained by comparison with previous exact quantum mechanical results, indicate that such methods are inappropriate not only for ''classically forbidden'' but for many ''classically allowed'' transitions (in spite of the fact that they are widely used to calculate probabilities for such processes). A classical path method in the context of infinite-order time-dependent perturbation theory is described which yields extremely accurate transition probabilities even for the most classically forbidden transitions in the collinear atom--harmonic oscillator system. The essential features of this method are: (1) the use of the expectation value of the total interaction potential in determining the atom--oscillator (central force) trajectory, and (2) the use of the arithmetic mean of the initial and final velocities of relative motion in the (elastic) central force trajectory. This choice of interaction potential allows the relative motion to be coupled to changes in the internal state of the oscillator. The present classical method is further applied to three-dimensional atom-breathing sphere collisions, and exact quantum mechanical calculations are also carried out. Comparison of the classical path and exact quantum results shows excellent agreement both in the specific inelastic cross section and in the individual partial-wave contributions

  18. Geometric phase of a classical Aharonov–Bohm Hamiltonian

    International Nuclear Information System (INIS)

    We present a gauge-invariant approach for associating a geometric phase with the phase space trajectory of a classical dynamical system. As an application, we consider the classical analog of the quantum Aharonov–Bohm (AB) Hamiltonian for a charged particle orbiting around a current carrying long thin solenoid. We compute the classical geometric phase of a closed phase space trajectory, and also determine its dependence on the magnetic flux enclosed by the orbit. We study the similarities and differences between this classical geometric phase and the AB phase acquired by the wave function of the quantum AB Hamiltonian. We suggest an experiment to measure the geometric phase for the classical AB system, by using an appropriate optical fiber ring interferometer.

  19. Geometric phase of a classical Aharonov–Bohm Hamiltonian

    Energy Technology Data Exchange (ETDEWEB)

    Balakrishnan, Radha, E-mail: radha@imsc.res.in [The Institute of Mathematical Sciences, Chennai 600 113 (India); Satija, Indubala I. [Department of Physics, George Mason University, Fairfax, VA 22030 (United States)

    2013-06-17

    We present a gauge-invariant approach for associating a geometric phase with the phase space trajectory of a classical dynamical system. As an application, we consider the classical analog of the quantum Aharonov–Bohm (AB) Hamiltonian for a charged particle orbiting around a current carrying long thin solenoid. We compute the classical geometric phase of a closed phase space trajectory, and also determine its dependence on the magnetic flux enclosed by the orbit. We study the similarities and differences between this classical geometric phase and the AB phase acquired by the wave function of the quantum AB Hamiltonian. We suggest an experiment to measure the geometric phase for the classical AB system, by using an appropriate optical fiber ring interferometer.

  20. Anderson localization from classical trajectories

    OpenAIRE

    Brouwer, Piet W.; Altland, Alexander

    2008-01-01

    We show that Anderson localization in quasi-one dimensional conductors with ballistic electron dynamics, such as an array of ballistic chaotic cavities connected via ballistic contacts, can be understood in terms of classical electron trajectories only. At large length scales, an exponential proliferation of trajectories of nearly identical classical action generates an abundance of interference terms, which eventually leads to a suppression of transport coefficients. We quantitatively descri...

  1. Gaussian Dynamics is Classical Dynamics

    OpenAIRE

    Habib, Salman

    2004-01-01

    A direct comparison of quantum and classical dynamical systems can be accomplished through the use of distribution functions. This is useful for both fundamental investigations such as the nature of the quantum-classical transition as well as for applications such as quantum feedback control. By affording a clear separation between kinematical and dynamical quantum effects, the Wigner distribution is particularly valuable in this regard. Here we discuss some consequences of the fact that when...

  2. Quantum systems as classical systems

    OpenAIRE

    Cassa, Antonio

    2001-01-01

    A characteristical property of a classical physical theory is that the observables are real functions taking an exact outcome on every (pure) state; in a quantum theory, at the contrary, a given observable on a given state can take several values with only a predictable probability. However, even in the classical case, when an observer is intrinsically unable to distinguish between some distinct states he can convince himself that the measure of its ''observables'' can have several values in ...

  3. Quantum money with classical verification

    International Nuclear Information System (INIS)

    We propose and construct a quantum money scheme that allows verification through classical communication with a bank. This is the first demonstration that a secure quantum money scheme exists that does not require quantum communication for coin verification. Our scheme is secure against adaptive adversaries - this property is not directly related to the possibility of classical verification, nevertheless none of the earlier quantum money constructions is known to possess it

  4. Classical theory of radiating strings

    Science.gov (United States)

    Copeland, Edmund J.; Haws, D.; Hindmarsh, M.

    1990-01-01

    The divergent part of the self force of a radiating string coupled to gravity, an antisymmetric tensor and a dilaton in four dimensions are calculated to first order in classical perturbation theory. While this divergence can be absorbed into a renormalization of the string tension, demanding that both it and the divergence in the energy momentum tensor vanish forces the string to have the couplings of compactified N = 1 D = 10 supergravity. In effect, supersymmetry cures the classical infinities.

  5. Quantum money with classical verification

    Energy Technology Data Exchange (ETDEWEB)

    Gavinsky, Dmitry [NEC Laboratories America, Princeton, NJ (United States)

    2014-12-04

    We propose and construct a quantum money scheme that allows verification through classical communication with a bank. This is the first demonstration that a secure quantum money scheme exists that does not require quantum communication for coin verification. Our scheme is secure against adaptive adversaries - this property is not directly related to the possibility of classical verification, nevertheless none of the earlier quantum money constructions is known to possess it.

  6. Planck's radiation law: is a quantum-classical perspective possible?

    Science.gov (United States)

    Marrocco, Michele

    2016-05-01

    Planck's radiation law provides the solution to the blackbody problem that marks the decline of classical physics and the rise of the quantum theory of the radiation field. Here, we venture to suggest the possibility that classical physics might be equally suitable to deal with the blackbody problem. A classical version of the Planck's radiation law seems to be achievable if we learn from the quantum-classical correspondence between classical Mie theory and quantum-mechanical wave scattering from spherical scatterers (partial wave analysis). This correspondence designs a procedure for countable energy levels of the radiation trapped within the blackbody treated within the multipole approach of classical electrodynamics (in place of the customary and problematic expansion in terms of plane waves that give rise to the ultraviolet catastrophe). In turn, introducing the Boltzmann discretization of energy levels, the tools of classical thermodynamics and statistical theory become available for the task. On the other hand, the final result depends on a free parameter whose physical units are those of an action. Tuning this parameter on the value given by the Planck constant makes the classical result agree with the canonical Planck's radiation law.

  7. Quantum computation with classical light: The Deutsch Algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Garcia, Benjamin [Photonics and Mathematical Optics Group, Tecnológico de Monterrey, Monterrey 64849 (Mexico); University of the Witwatersrand, Private Bag 3, Johannesburg 2050 (South Africa); Francis, Jason [School of Chemistry and Physics, University of KwaZulu-Natal, Private Bag X54001, Durban 4000 (South Africa); McLaren, Melanie [University of the Witwatersrand, Private Bag 3, Johannesburg 2050 (South Africa); Hernandez-Aranda, Raul I. [Photonics and Mathematical Optics Group, Tecnológico de Monterrey, Monterrey 64849 (Mexico); Forbes, Andrew [University of the Witwatersrand, Private Bag 3, Johannesburg 2050 (South Africa); Konrad, Thomas, E-mail: konradt@ukzn.ac.za [School of Chemistry and Physics, University of KwaZulu-Natal, Private Bag X54001, Durban 4000 (South Africa); National Institute of Theoretical Physics, Durban Node, Private Bag X54001, Durban 4000 (South Africa)

    2015-08-28

    We present an implementation of the Deutsch Algorithm using linear optical elements and laser light. We encoded two quantum bits in form of superpositions of electromagnetic fields in two degrees of freedom of the beam: its polarisation and orbital angular momentum. Our approach, based on a Sagnac interferometer, offers outstanding stability and demonstrates that optical quantum computation is possible using classical states of light. - Highlights: • We implement the Deutsh Algorithm using linear optical elements and classical light. • Our qubits are encoded in the polarisation and orbital angular momentum of the beam. • We show that it is possible to achieve quantum computation with two qubits in the classical domain of light.

  8. Quantum computation with classical light: The Deutsch Algorithm

    International Nuclear Information System (INIS)

    We present an implementation of the Deutsch Algorithm using linear optical elements and laser light. We encoded two quantum bits in form of superpositions of electromagnetic fields in two degrees of freedom of the beam: its polarisation and orbital angular momentum. Our approach, based on a Sagnac interferometer, offers outstanding stability and demonstrates that optical quantum computation is possible using classical states of light. - Highlights: • We implement the Deutsh Algorithm using linear optical elements and classical light. • Our qubits are encoded in the polarisation and orbital angular momentum of the beam. • We show that it is possible to achieve quantum computation with two qubits in the classical domain of light

  9. A Survey on the Classical Limit of Quantum Dynamical Entropies

    CERN Document Server

    Cappellini, Valerio

    2007-01-01

    We analyze the behavior of quantum dynamical entropies production from sequences of quantum approximants approaching their (chaotic) classical limit. The model of the quantized hyperbolic automorphisms of the 2-torus is examined in detail and a semi-classical analysis is performed on it using coherent states, fulfilling an appropriate dynamical localization property. Correspondence between quantum dynamical entropies and the Kolmogorov-Sinai invariant is found only over time scales that are logarithmic in the quantization parameter.

  10. Are we ready to move beyond the reductionist approach of classical synergy control?. Comment on "Hand synergies: Integration of robotics and neuroscience for understanding the control of biological and artificial hands" by Marco Santello et al.

    Science.gov (United States)

    Lacquaniti, Francesco; Ivanenko, Yuri P.; Zago, Myrka

    2016-07-01

    Starting from the classical concepts introduced by Sherrington [1] and considerably elaborated by Bernstein [2], much has been learned about motor synergies in the last several years. The contributions of the group funded by the European project "The Hand Embodied" are remarkable in the field of biological and robotic control of the hand based on synergies, and they are reflected in this enjoyable review [3]. There, Santello et al. adopt Bernstein's definition of motor synergies as multiple elements working together towards a common goal, with the result that multiple degrees of freedom are controlled within a lower-dimensional space than the available number of dimensions.

  11. Does classical liberalism imply democracy?

    Directory of Open Access Journals (Sweden)

    David Ellerman

    2015-12-01

    Full Text Available There is a fault line running through classical liberalism as to whether or not democratic self-governance is a necessary part of a liberal social order. The democratic and non-democratic strains of classical liberalism are both present today—particularly in the United States. Many contemporary libertarians and neo-Austrian economists represent the non-democratic strain in their promotion of non-democratic sovereign city-states (start-up cities or charter cities. We will take the late James M. Buchanan as a representative of the democratic strain of classical liberalism. Since the fundamental norm of classical liberalism is consent, we must start with the intellectual history of the voluntary slavery contract, the coverture marriage contract, and the voluntary non-democratic constitution (or pactum subjectionis. Next we recover the theory of inalienable rights that descends from the Reformation doctrine of the inalienability of conscience through the Enlightenment (e.g. Spinoza and Hutcheson in the abolitionist and democratic movements. Consent-based governments divide into those based on the subjects’ alienation of power to a sovereign and those based on the citizens’ delegation of power to representatives. Inalienable rights theory rules out that alienation in favor of delegation, so the citizens remain the ultimate principals and the form of government is democratic. Thus the argument concludes in agreement with Buchanan that the classical liberal endorsement of sovereign individuals acting in the marketplace generalizes to the joint action of individuals as the principals in their own organizations.

  12. No Return to Classical Reality

    CERN Document Server

    Jennings, David

    2015-01-01

    At a fundamental level, the classical picture of the world is dead, and has been dead now for almost a century. Pinning down exactly which quantum phenomena are responsible for this has proved to be a tricky and controversial question, but a lot of progress has been made in the past few decades. We now have a range of precise statements showing that whatever the ultimate laws of Nature are, they cannot be classical. In this article, we review results on the fundamental phenomena of quantum theory that cannot be understood in classical terms. We proceed by first granting quite a broad notion of classicality, describe a range of quantum phenomena (such as randomness, discreteness, the indistinguishability of states, measurement-uncertainty, measurement-disturbance, complementarity, noncommutativity, interference, the no-cloning theorem, and the collapse of the wave-packet) that do fall under its liberal scope, and then finally describe some aspects of quantum physics that can never admit a classical understandi...

  13. Beyond the borders of classical optical measurements

    International Nuclear Information System (INIS)

    Full Text: The limits of optical measurements are the subject to many recent works. It has been shown how by using non-classical photonic states, spatial resolution can exceed the diffraction limit [1]. The same states also improve interference measurements beyond the shot noise and up to the quantum Heisenberg limit [2]. On the other hand, a few methods have been suggested that improve the optical resolution by exploiting classical optical nonlinearities [3]. First, we will present a scheme that exploits the non-local quantum correlations of a second order entangled state produced by optical parametric down-conversion [4]. The scheme results with a non-classical state that can be used in quantum limited interferometry. It is also simply extendable to states of any photon number. Another method will be presented, where nonlinear measurements are induced by projecting the state of light onto the Fock space [5]. This process simulated optical nonlinearities up to the 7th order. We used those measurements to characterize the output of a standard polarization interferometer. Improved resolution was demonstrated, but a detailed analysis reveals the differences to the previous nonclassical approach

  14. The classical limit of non-integrable quantum systems

    CERN Document Server

    Castagnino, M; Castagnino, Mario; Lombardi, Olimpia

    2005-01-01

    The classical limit of non-integrable quantum systems is studied. We define non-integrable quantum systems as those which have, as their classical limit, a non-integrable classical system. In order to obtain this limit, the self-induced decoherence approach and the corresponding classical limit are generalized from integrable to non-integrable systems. In this approach, the lost of information, usually conceived as the result of a coarse-graining or the trace of an environment, is produced by a particular choice of the algebra of observables and the systematic use of mean values, that project the unitary evolution onto an effective non-unitary one. The decoherence times computed with this approach coincide with those of the literature. By means of our method, we can obtain the classical limit of the quantum state of a non-integrable system, which turns out to be a set of unstable, potentially chaotic classical trajectories contained in the Wigner transformation of the quantum state.

  15. How Quantum is the Classical World?

    CERN Document Server

    Schmid, Gary Bruno

    2011-01-01

    It has been experimentally confirmed that quantum physical phenomena can violate the Information Bell Inequalities. A violation of the one or the other of these Information Bell Inequalites is equivalent to a violation of local realism meaning that either objectivity or locality, or both, do not hold for the phenomena under investigation. We propose (1) an experimental design for carrying out classical measurements in the absence of ontological complementarity; (2) a rational way to extract epistemologically complementary (pseudocomplementary) data from it; (3) a statistical approach which can reject stochastic and/or suspected violations of local realism in measurements of such data.

  16. Soliton splitting in quenched classical integrable systems

    Science.gov (United States)

    Gamayun, O.; Semenyakin, M.

    2016-08-01

    We take a soliton solution of a classical non-linear integrable equation and quench (suddenly change) its non-linearity parameter. For that we multiply the amplitude or the width of a soliton by a numerical factor η and take the obtained profile as a new initial condition. We find the values of η for which the post-quench solution consists of only a finite number of solitons. The parameters of these solitons are found explicitly. Our approach is based on solving the direct scattering problem analytically. We demonstrate how it works for Korteweg–de Vries, sine-Gordon and non-linear Schrödinger integrable equations.

  17. On the Galilean covariance of classical mechanics

    International Nuclear Information System (INIS)

    A Galilean covariant approach to classical mechanics of a single interacting particle is described. In this scheme constitutive relations defining forces are rejected and acting forces are determined by some fundamental differential equations. It is shown that total energy of the interacting particle transforms under Galilean transformations differently from the kinetic energy. The statement is illustrated on the exactly solvable examples of the harmonic oscillator and the case of constant forces and also, in the suitable version of the perturbation theory, for the anharmonic oscillator. (author)

  18. Classical isodual theory of antimatter

    CERN Document Server

    Santilli, R M

    1997-01-01

    An inspection of the contemporary physics literature reveals that, while matter is treated at all levels of study, from Newtonian mechanics to quantum field theory, antimatter is solely treated at the level of second quantization. For the purpose of initiating the restoration of full equivalence in the treatments of matter and antimatter in due time, in this paper we present a classical representation of antimatter which begins at the primitive Newtonian level with expected images at all subsequent levels. By recalling that charge conjugation of particles into antiparticles is anti-automorphic, the proposed theory of antimatter is based on a new map, called isoduality, which is also anti-automorphic, yet it is applicable beginning at the classical level and then persists at the quantum level. As part of our study, we present novel anti-isomorphic isodual images of the Galilean, special and general relativities and show the compatibility of their representation of antimatter with all available classical experi...

  19. Casimir Effect The Classical Limit

    CERN Document Server

    Feinberg, J; Revzen, M

    2001-01-01

    We analyze the high temperature limit of the Casimir effect. A simple physical argument suggests that the Casimir energy (as opposed to the Casimir free energy) should vanish in the classical limit. We check the validity of this argument for massless scalar field confined in a cavity with boundaries of arbitrary shape, using path integral formalism. We are able to verify this suggestion only when the boundaries consist of disjoint pieces. Moreover, we find in these cases that the contribution to the Casimir entropy by field modes that depend on that separation, tends, in the classical limit, to a finite asymptotic value which depends only on the geometry of the cavity. Thus the Casimir force between disjoint pieces of the boundary in the classical limit is entropy driven and is governed by a dimensionless number characterizing the arbitrary geometry of the cavity. Contributions to the Casimir thermodynamical quantities due to each individual connected component of the boundary exhibit logarithmic deviations i...

  20. Population in the classic economics

    Directory of Open Access Journals (Sweden)

    Adnan Doğruyol

    2013-02-01

    Full Text Available Growth subject in economics is an important factor of development. Classic economics ecole indicates the population as main variable which tender of growth. On the other hand T. R. Malthus is known as economist who regards population as a problem and brings up it among the classical economists. However, Adam Smith is an intellectual who discussed population problem earlier on the classic economics theory. According to Adam Smith one of the main factors that realise the growth is labour. In addition to population made it established. The aim of this study is analyzing the mental relationship between Malthus whose name has been identified with relation between population-growth and Smith who discussed this subject first time but put it off on process of theorisation.

  1. Comparing classical and quantum equilibration

    CERN Document Server

    Malabarba, Artur S L; Short, Anthony J

    2016-01-01

    By using a physically-relevant and theory independent definition of measurement-based equilibration, we show quantitatively that equilibration is easier for quantum systems than for classical systems, in the situation where the initial state of the system is completely known (pure state). This shows that quantum equilibration is a fundamental, nigh unavoidable, aspect of physical systems, while classical equilibration relies on experimental ignorance. When the state is not completely known, a mixed state, this framework also shows quantum equilibration requires weaker conditions.

  2. Classical planning and causal implicatures

    DEFF Research Database (Denmark)

    Blackburn, Patrick Rowan; Benotti, Luciana

    In this paper we motivate and describe a dialogue manager (called Frolog) which uses classical planning to infer causal implicatures. A causal implicature is a type of Gricean relation implicature, a highly context dependent form of inference. As we shall see, causal implicatures are important for...... generate clarification requests"; as a result we can model task-oriented dialogue as an interactive process locally structured by negotiation of the underlying task. We give several examples of Frolog-human dialog, discuss the limitations imposed by the classical planning paradigm, and indicate the...

  3. Identity from classical invariant theory

    International Nuclear Information System (INIS)

    A simple derivation is given of a well-known relation involving the so-called Cayley Operator of classical invariant theory. The proof is induction-free and independent of Capelli's identity; it makes use only of a known-theorem in the theory of determinants and some elementary combinatorics

  4. On classical and quantum liftings

    OpenAIRE

    Accardi, L.; Chruściński, Dariusz; Kossakowski, Andrzej; Matsuoka, T.; Ohya, Masanori

    2011-01-01

    We analyze the procedure of lifting in classical stochastic and quantum systems. It enables one to `lift' a state of a system into a state of `system+reservoir'. This procedure is important both in quantum information theory and the theory of open systems. We illustrate the general theory of liftings by a particular class related to so called circulant states.

  5. Classical Virasoro irregular conformal block

    CERN Document Server

    Rim, Chaiho

    2015-01-01

    Virasoro irregular conformal block with arbitrary rank is obtained for the classical limit or equivalently Nekrasov-Shatashvili limit using the beta-deformed irregular matrix model (Penner-type matrix model for the irregular conformal block). The same result is derived using the generalized Mathieu equation which is equivalent to the loop equation of the irregular matrix model.

  6. Teaching Classical Mechanics Using Smartphones

    Science.gov (United States)

    Chevrier, Joel; Madani, Laya; Ledenmat, Simon; Bsiesy, Ahmad

    2013-01-01

    A number of articles published in this column have dealt with topics in classical mechanics. This note describes some additional examples employing a smartphone and the new software iMecaProf. Steve Jobs presented the iPhone as "perfect for gaming." Thanks to its microsensors connected in real time to the numerical world, physics…

  7. Classical Music as Enforced Utopia

    Science.gov (United States)

    Leech-Wilkinson, Daniel

    2016-01-01

    In classical music composition, whatever thematic or harmonic conflicts may be engineered along the way, everything always turns out for the best. Similar utopian thinking underlies performance: performers see their job as faithfully carrying out their master's (the composer's) wishes. The more perfectly they represent them, the happier the…

  8. Measurement-Based Classical Computation

    Science.gov (United States)

    Hoban, Matty J.; Wallman, Joel J.; Anwar, Hussain; Usher, Naïri; Raussendorf, Robert; Browne, Dan E.

    2014-04-01

    Measurement-based quantum computation (MBQC) is a model of quantum computation, in which computation proceeds via adaptive single qubit measurements on a multiqubit quantum state. It is computationally equivalent to the circuit model. Unlike the circuit model, however, its classical analog is little studied. Here we present a classical analog of MBQC whose computational complexity presents a rich structure. To do so, we identify uniform families of quantum computations [refining the circuits introduced by Bremner et al. Proc. R. Soc. A 467, 459 (2010)] whose output is likely hard to exactly simulate (sample) classically. We demonstrate that these circuit families can be efficiently implemented in the MBQC model without adaptive measurement and, thus, can be achieved in a classical analog of MBQC whose resource state is a probability distribution which has been created quantum mechanically. Such states (by definition) violate no Bell inequality, but, if widely held beliefs about computational complexity are true, they, nevertheless, exhibit nonclassicality when used as a computational resource—an imprint of their quantum origin.

  9. Invariants in Supersymmetric Classical Mechanics

    OpenAIRE

    Alonso Izquierdo, Alberto; González León, Miguel Ángel; Mateos Guilarte, Juan

    2000-01-01

    [EN] The bosonic second invariant of SuperLiouville models in supersymmetric classical mechanics is described. [ES] El segundo campo cuántico de bosones invariante del modelo SuperLiouville es descrito en la mecanica clasica supersimétrica.

  10. Quantum Proofs for Classical Theorems

    OpenAIRE

    Drucker, A.; Wolf,

    2009-01-01

    Alongside the development of quantum algorithms and quantum complexity theory in recent years, quantum techniques have also proved instrumental in obtaining results in classical (non-quantum) areas. In this paper we survey these results and the quantum toolbox they use.

  11. Functional Techniques in Classical Mechanics

    CERN Document Server

    Gozzi, E

    2001-01-01

    In 1931 Koopman and von Neumann extended previous work of Liouville and provided an operatorial version of Classical Mechanics (CM). In this talk we will review a path-integral formulation of this operatorial version of CM. In particular we will study the geometrical nature of the many auxiliary variables present and of the unexpected universal symmetries generated by the functional technique.

  12. Agglomeration Economies in Classical Music

    DEFF Research Database (Denmark)

    Borowiecki, Karol Jan

    2015-01-01

    This study investigates agglomeration effects for classical music production in a wide range of cities for a global sample of composers born between 1750 and 1899. Theory suggests a trade-off between agglomeration economies (peer effects) and diseconomies (peer crowding). I test this hypothesis...

  13. Neo-classical impurity transport

    International Nuclear Information System (INIS)

    The neo-classical theory for impurity transport in a toroidal plasma is outlined, and the results discussed. A general account is given of the impurity behaviour and its dependence on collisionality. The underlying physics is described with special attention to the role of the poloidal rotation

  14. On Classical and Quantum Cryptography

    OpenAIRE

    I. V. Volovich; Volovich, Ya. I.

    2001-01-01

    Lectures on classical and quantum cryptography. Contents: Private key cryptosystems. Elements of number theory. Public key cryptography and RSA cryptosystem. Shannon`s entropy and mutual information. Entropic uncertainty relations. The no cloning theorem. The BB84 quantum cryptographic protocol. Security proofs. Bell`s theorem. The EPRBE quantum cryptographic protocol.

  15. Supersymmetric classical mechanics: free case

    International Nuclear Information System (INIS)

    We present a review work on Supersymmetric Classical Mechanics in the context of a Lagrangian formalism, with N = 1-supersymmetry. We show that the N = 1 supersymmetry does not allow the introduction of a potencial energy term depending on a single commuting supercoordinate, φ(t;Θ). (author)

  16. Methodological issues regarding power of classical test theory (CTT and item response theory (IRT-based approaches for the comparison of patient-reported outcomes in two groups of patients - a simulation study

    Directory of Open Access Journals (Sweden)

    Boyer François

    2010-03-01

    Full Text Available Abstract Background Patients-Reported Outcomes (PRO are increasingly used in clinical and epidemiological research. Two main types of analytical strategies can be found for these data: classical test theory (CTT based on the observed scores and models coming from Item Response Theory (IRT. However, whether IRT or CTT would be the most appropriate method to analyse PRO data remains unknown. The statistical properties of CTT and IRT, regarding power and corresponding effect sizes, were compared. Methods Two-group cross-sectional studies were simulated for the comparison of PRO data using IRT or CTT-based analysis. For IRT, different scenarios were investigated according to whether items or person parameters were assumed to be known, to a certain extent for item parameters, from good to poor precision, or unknown and therefore had to be estimated. The powers obtained with IRT or CTT were compared and parameters having the strongest impact on them were identified. Results When person parameters were assumed to be unknown and items parameters to be either known or not, the power achieved using IRT or CTT were similar and always lower than the expected power using the well-known sample size formula for normally distributed endpoints. The number of items had a substantial impact on power for both methods. Conclusion Without any missing data, IRT and CTT seem to provide comparable power. The classical sample size formula for CTT seems to be adequate under some conditions but is not appropriate for IRT. In IRT, it seems important to take account of the number of items to obtain an accurate formula.

  17. Nonadiabatic nuclear dynamics of atomic collisions based on branching classical trajectories

    International Nuclear Information System (INIS)

    The branching classical trajectory method for inelastic atomic collision processes is proposed. The approach is based on two features: (i) branching of a classical trajectory in a nonadiabatic region and (ii) the nonadiabatic transition probability formulas particularly adapted for a classical trajectory treatment. In addition to transition probabilities and inelastic cross sections, the proposed approach allows one to calculate incoming and outgoing currents. The method is applied to inelastic Na + H collisions providing the results in reasonable agreement with full quantum calculations.

  18. Ising models and topological codes: classical algorithms and quantum simulation

    CERN Document Server

    Nest, M Van den

    2014-01-01

    We present an algorithm to approximate partition functions of 3-body classical Ising models on two-dimensional lattices of arbitrary genus, in the real-temperature regime. Even though our algorithm is purely classical, it is designed by exploiting a connection to topological quantum systems, namely the color codes. The algorithm performance is exponentially better than other approaches which employ mappings between partition functions and quantum state overlaps. In addition, our approach gives rise to a protocol for quantum simulation of such Ising models by simply measuring local observables on color codes.

  19. Teaching Classical Mechanics using Smartphones

    CERN Document Server

    Chevrier, Joel; Ledenmat, Simon; Bsiesy, Ahmad

    2012-01-01

    Using a personal computer and a smartphone, iMecaProf is a software that provides a complete teaching environment for practicals associated to a Classical Mechanics course. iMecaProf proposes a visual, real time and interactive representation of data transmitted by a smartphone using the formalism of Classical Mechanics. Using smartphones is more than using a set of sensors. iMecaProf shows students that important concepts of physics they here learn, are necessary to control daily life smartphone operations. This is practical introduction to mechanical microsensors that are nowadays a key technology in advanced trajectory control. First version of iMecaProf can be freely downloaded. It will be tested this academic year in Universit\\'e Joseph Fourier (Grenoble, France)

  20. Classical Concepts in Quantum Programming

    CERN Document Server

    Oemer, B

    2002-01-01

    The rapid progress of computer technology has been accompanied by a corresponding evolution of software development, from hardwired components and binary machine code to high level programming languages, which allowed to master the increasing hardware complexity and fully exploit its potential. This paper investigates, how classical concepts like hardware abstraction, hierarchical programs, data types, memory management, flow of control and structured programming can be used in quantum computing. The experimental language QCL will be introduced as an example, how elements like irreversible functions, local variables and conditional branching, which have no direct quantum counterparts, can be implemented, and how non-classical features like the reversibility of unitary transformation or the non-observability of quantum states can be accounted for within the framework of a procedural programming language.

  1. Classical theory of algebraic numbers

    CERN Document Server

    Ribenboim, Paulo

    2001-01-01

    Gauss created the theory of binary quadratic forms in "Disquisitiones Arithmeticae" and Kummer invented ideals and the theory of cyclotomic fields in his attempt to prove Fermat's Last Theorem These were the starting points for the theory of algebraic numbers, developed in the classical papers of Dedekind, Dirichlet, Eisenstein, Hermite and many others This theory, enriched with more recent contributions, is of basic importance in the study of diophantine equations and arithmetic algebraic geometry, including methods in cryptography This book has a clear and thorough exposition of the classical theory of algebraic numbers, and contains a large number of exercises as well as worked out numerical examples The Introduction is a recapitulation of results about principal ideal domains, unique factorization domains and commutative fields Part One is devoted to residue classes and quadratic residues In Part Two one finds the study of algebraic integers, ideals, units, class numbers, the theory of decomposition, iner...

  2. Classical Probability and Quantum Outcomes

    Directory of Open Access Journals (Sweden)

    James D. Malley

    2014-05-01

    Full Text Available There is a contact problem between classical probability and quantum outcomes. Thus, a standard result from classical probability on the existence of joint distributions ultimately implies that all quantum observables must commute. An essential task here is a closer identification of this conflict based on deriving commutativity from the weakest possible assumptions, and showing that stronger assumptions in some of the existing no-go proofs are unnecessary. An example of an unnecessary assumption in such proofs is an entangled system involving nonlocal observables. Another example involves the Kochen-Specker hidden variable model, features of which are also not needed to derive commutativity. A diagram is provided by which user-selected projectors can be easily assembled into many new, graphical no-go proofs.

  3. From classical to quantum physics

    CERN Document Server

    Stehle, Philip

    2017-01-01

    Suitable for lay readers as well as students, this absorbing survey explores the twentieth-century transition from classical to quantum physics. Author Philip Stehle traces the shift in the scientific worldview from the work of Galileo, Newton, and Darwin to the modern-day achievements of Max Planck, Albert Einstein, Ernest Rutherford, Niels Bohr, and others of their generation. His insightful overview examines not only the history of quantum physics but also the ways that progress in the discipline changed our understanding of the physical world and forces of nature. This chronicle of the second revolution in the physical sciences conveys the excitement and suspense that new developments produced in the scientific community. The narrative ranges from the classical physics of the seventeenth-century to the emergence of quantum mechanics with the entrance of the electron, the rise of relativity theory, the development of atomic theory, and the recognition of wave-particle duality. Relevant mathematical details...

  4. Classical Models of Subatomic Particles

    OpenAIRE

    Mann, R. B.; Morris, M. S.

    1993-01-01

    We look at the program of modelling a subatomic particle---one having mass, charge, and angular momentum---as an interior solution joined to a classical general-relativistic Kerr-Newman exterior spacetime. We find that the assumption of stationarity upon which the validity of the Kerr-Newman exterior solution depends is in fact violated quantum mechanically for all known subatomic particles. We conclude that the appropriate stationary spacetime matched to any known subatomic particle is flat ...

  5. Classical models of subatomic particles

    International Nuclear Information System (INIS)

    We look at the program of modelling a subatomic particle - one having mass, charge, and angular momentum - as an interior solution joined to a classical general-relativistic Kerr-Newman exterior spacetime. We find that the assumption of stationarity upon which the validity of the Kerr-Newman exterior solution depends is in fact violated quantum mechanically for all known subatomic particles. We conclude that the appropriate stationary spacetime matched to any known subatomic particle is flat space. (orig.)

  6. Classic ballet dancers postural patterns

    OpenAIRE

    Joseani Paulini Neves Simas; Sebastião Iberes Lopes Melo

    2008-01-01

    The aim of this study was to evaluate classic ballet practice and its influence on postural patterns and (a) identify the most frequent postural changes; (b) determine the postural pattern; (c) verify the existence of association of practice time and postural changes. The investigation was carried out in two stages: one, description in which 106 dancers participated; the other, causal comparative in which 50 dancers participated; and (a) questionnaire; (b) a checkerboard; (c) postural chart; ...

  7. Classical Concepts in Quantum Programming

    OpenAIRE

    Oemer, Bernhard

    2002-01-01

    The rapid progress of computer technology has been accompanied by a corresponding evolution of software development, from hardwired components and binary machine code to high level programming languages, which allowed to master the increasing hardware complexity and fully exploit its potential. This paper investigates, how classical concepts like hardware abstraction, hierarchical programs, data types, memory management, flow of control and structured programming can be used in quantum comput...

  8. Gauge Invariance in Classical Electrodynamics

    CERN Document Server

    Engelhardt, W

    2005-01-01

    The concept of gauge invariance in classical electrodynamics assumes tacitly that Maxwell's equations have unique solutions. By calculating the electromagnetic field of a moving particle both in Lorenz and in Coulomb gauge and directly from the field equations we obtain, however, contradicting solutions. We conclude that the tacit assumption of uniqueness is not justified. The reason for this failure is traced back to the inhomogeneous wave equations which connect the propagating fields and their sources at the same time.

  9. To Foundations of Classical Electrodynamics

    OpenAIRE

    Bessonov, E. G.

    1997-01-01

    In the present work foundations of the law of the energy conservation and the introduction of particles in the classical electrodynamics are discussed. We pay attention to a logic error which takes place at an interpretation of the Poynting's theorem as the law of conservation of energy. It was shown that the laws of conservation of energy and momentum of the system of electromagnetic fields and charged particles does not follow from the equations of electrodynamics and the violation of these...

  10. Applications of classical detonation theory

    Energy Technology Data Exchange (ETDEWEB)

    Davis, W.C.

    1994-09-01

    Classical detonation theory is the basis for almost all calculations of explosive systems. One common type of calculation is of the detailed behavior of inert parts driven by explosive, predicting pressures, velocities, positions, densities, energies, etc as functions of time. Another common application of the theory is predicting the detonation state and expansion isentrope of a new explosive or mixtures, perhaps an explosive that has not yet been made. Both types of calculations are discussed.

  11. Rindler particles and classical radiation

    International Nuclear Information System (INIS)

    We describe the quantum and classical radiation emitted by a uniformly accelerating point source in terms of the elementary processes of absorption and emission of Rindler scalar photons of the Fulling-Davies-Unruh bath observed by a co-accelerating observer. To this end we compute the rate at which a DeWitt detector emits a Minkowski scalar particle with defined transverse momentum per unit of proper time of the source and we show that it corresponds to the induced absorption or spontaneous and induced emission of Rindler particles from the thermal bath. We then take what could be called the inert limit of the DeWitt detector by considering the limit of no energy gap. As suggested by DeWitt, we identify, in this limit, the detector with a classical point source and verify the consistency of our computation with the classical result. Finally, we study the behaviour of the emission rate in D spacetime dimensions in connection with the so-called apparent statistics inversion

  12. Rindler Photons and Classical Radiation

    CERN Document Server

    Díaz, D E

    2001-01-01

    We describe the quantum and classical radiation by a uniformly accelerating point source in terms of the elementary processes of absorption and emission of Rindler scalar photons of the Fulling-Davies-Unruh bath observed by a co-accelerating observer.To this end we compute the emission rate by a DeWitt detector of a Minkowski scalar field particle with defined transverse momentum per unit of proper time of the source and we show that it corresponds to the induced absorption or spontaneous and induced emission of Rindler photons from the thermal bath. We then take what could be called the inert limit of the DeWitt detector by considering the limit of zero gap energy. As suggested by DeWitt, we identify in this limit the detector with a classical point source and verify the consistency of our computation with the classical result. Finally, we study the behavior of the emission rate in D space-time dimensions in connection with the so called apparent statistics inversion.

  13. Quantum systems as classical systems

    CERN Document Server

    Cassa, A

    2001-01-01

    A characteristical property of a classical physical theory is that the observables are real functions taking an exact outcome on every (pure) state; in a quantum theory, at the contrary, a given observable on a given state can take several values with only a predictable probability. However, even in the classical case, when an observer is intrinsically unable to distinguish between some distinct states he can convince himself that the measure of its ''observables'' can have several values in a random way with a statistical character. What kind of statistical theory is obtainable in this way? It is possible, for example, to obtain exactly the statistical previsions of quantum mechanics? Or, in other words, can a physical system showing a classical behaviour appear to be a quantum system to a confusing observer? We show that from a mathematical viewpoint it is not difficult to produce a theory with hidden variables having this property. We don't even try to justify in physical terms the artificial construction ...

  14. Quantum to Classical Randomness Extractors

    CERN Document Server

    Berta, Mario; Wehner, Stephanie

    2011-01-01

    Even though randomness is an essential resource for many information processing tasks, it is not easily found in nature. The goal of randomness extraction is to distill (almost) perfect randomness from a weak source of randomness. When the source yields a classical string X, many extractor constructions are known. Yet, when considering a physical randomness source, X is itself ultimately the result of a measurement on an underlying quantum system. When characterizing the power of a source to supply randomness it is hence a natural question to ask, how much classical randomness we can extract from a quantum state. To tackle this question we here take on the study of quantum-to-classical randomness extractors (QC-extractors). We provide constructions of QC-extractors based on measurements in a full set of mutually unbiased bases (MUBs), and certain single qubit measurements. As the first application, we show that any QC-extractor gives rise to entropic uncertainty relations with respect to quantum side informat...

  15. Anthropomorphic Quantum Darwinism as an explanation for Classicality

    CERN Document Server

    Durt, Thomas

    2009-01-01

    According to the so-called ``Quantum Darwinist'' approach, the emergence of ``classical islands'' from a quantum background is assumed to obey a (selection) principle of maximal information. We illustrate this idea by considering the coupling of two particles that interact through a position-dependent potential. This approach sheds a new light on the emergence of classical logics and of our classical preconceptions about the world. The distinction between internal and external world, the Cartesian prejudice according to which the whole can be reduced to the sum of its parts and the appearance of preferred representation bases such as the position is seen here as the result of a very long evolution and would correspond to the most useful way of extracting stable and useful information from the quantum correlations.

  16. Why do cosmological perturbations look classical to us?

    CERN Document Server

    Kiefer, Claus

    2008-01-01

    According to the inflationary scenario of cosmology, all structure in the Universe can be traced back to primordial fluctuations during an accelerated (inflationary) phase of the very early Universe. A conceptual problem arises due to the fact that the primordial fluctuations are quantum, while the standard scenario of structure formation deals with classical fluctuations. In this essay we present a concise summary of the physics describing the quantum-to-classical transition. We first discuss the observational indistinguishability between classical and quantum correlation functions in the closed system approach (pragmatic view). We then present the open system approach with environment-induced decoherence. We finally discuss the question of the fluctuations' entropy for which, in principle, the concrete mechanism leading to decoherence possesses observational relevance.

  17. Embedding quantum into classical: contextualization vs conditionalization.

    Directory of Open Access Journals (Sweden)

    Ehtibar N Dzhafarov

    Full Text Available We compare two approaches to embedding joint distributions of random variables recorded under different conditions (such as spins of entangled particles for different settings into the framework of classical, Kolmogorovian probability theory. In the contextualization approach each random variable is "automatically" labeled by all conditions under which it is recorded, and the random variables across a set of mutually exclusive conditions are probabilistically coupled (imposed a joint distribution upon. Analysis of all possible probabilistic couplings for a given set of random variables allows one to characterize various relations between their separate distributions (such as Bell-type inequalities or quantum-mechanical constraints. In the conditionalization approach one considers the conditions under which the random variables are recorded as if they were values of another random variable, so that the observed distributions are interpreted as conditional ones. This approach is uninformative with respect to relations between the distributions observed under different conditions because any set of such distributions is compatible with any distribution assigned to the conditions.

  18. The Relation between Classical and Quantum Electrodynamics

    Directory of Open Access Journals (Sweden)

    Mario Bacelar Valente

    2011-01-01

    Full Text Available Quantum electrodynamics presents intrinsic limitations in the description of physical processes that make it impossible to recover from it the type of description we have in classical electrodynamics. Hence one cannot consider classical electrodynamics as reducing to quantum electrodynamics and being recovered from it by some sort of limiting procedure. Quantum electrodynamics has to be seen not as an more fundamental theory, but as an upgrade of classical electrodynamics, which permits an extension of classical theory to the description of phenomena that, while being related to the conceptual framework of the classical theory, cannot be addressed from the classical theory.

  19. Classical versus Computer Algebra Methods in Elementary Geometry

    Science.gov (United States)

    Pech, Pavel

    2005-01-01

    Computer algebra methods based on results of commutative algebra like Groebner bases of ideals and elimination of variables make it possible to solve complex, elementary and non elementary problems of geometry, which are difficult to solve using a classical approach. Computer algebra methods permit the proof of geometric theorems, automatic…

  20. Monodromic vs geodesic computation of Virasoro classical conformal blocks

    Directory of Open Access Journals (Sweden)

    Konstantin Alkalaev

    2016-03-01

    Full Text Available We compute 5-point classical conformal blocks with two heavy, two light, and one superlight operator using the monodromy approach up to third order in the superlight expansion. By virtue of the AdS/CFT correspondence we show the equivalence of the resulting expressions to those obtained in the bulk computation for the corresponding geodesic configuration.

  1. On gravitational waves from classical three body problem

    CERN Document Server

    Fiziev, Plamen P

    2016-01-01

    Using an effective one body approach we describe in detail gravitational waves from classical three body problem on a non-rotating straight line and derive their basic physical characteristics. Special attention is paid to the irregular motions of such systems and to the significance of double and triple collisions. The conclusive role of the collinear solutions is also discussed in short.

  2. Advances In Classical Field Theory

    CERN Document Server

    Yahalom, Asher

    2011-01-01

    Classical field theory is employed by physicists to describe a wide variety of physical phenomena. These include electromagnetism, fluid dynamics, gravitation and quantum mechanics. The central entity of field theory is the field which is usually a multi component function of space and time. Those multi component functions are usually grouped together as vector fields as in the case in electromagnetic theory and fluid dynamics, in other cases they are grouped as tensors as in theories of gravitation and yet in other cases they are grouped as complex functions as in the case of quantum mechanic

  3. Superadditivity of classical capacity revisited

    Energy Technology Data Exchange (ETDEWEB)

    Pilyavets, Oleg V.; Karpov, Evgueni A.; Schäfer, Joachim [QuIC, Ecole Polytechnique, Université Libre de Bruxelles, CP 165, 1050 Brussels (Belgium)

    2014-12-04

    We introduce new type of superadditivity for classical capacity of quantum channels, which involves the properties of channels’ environment. By imposing different restrictions on the total energy contained in channels’ environment we can consider different types of superadditivity. Using lossy bosonic and additive noise quantum channels as examples, we demonstrate that their capacities can be either additive or superadditive depending on the values of channels parameters. The parameters corresponding to transition between the additive and superadditive cases are related with recently found critical and supercritical parameters for Gaussian channels.

  4. Lectures on classical differential geometry

    CERN Document Server

    Struik, Dirk J

    1988-01-01

    Elementary, yet authoritative and scholarly, this book offers an excellent brief introduction to the classical theory of differential geometry. It is aimed at advanced undergraduate and graduate students who will find it not only highly readable but replete with illustrations carefully selected to help stimulate the student's visual understanding of geometry. The text features an abundance of problems, most of which are simple enough for class use, and often convey an interesting geometrical fact. A selection of more difficult problems has been included to challenge the ambitious student.Writ

  5. Solar Activity and Classical Physics

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    This review of solar physics emphasizes several of the more conspicuous scientific puzzles posed by contemporary observational knowledge of the magnetic activity of the Sun. The puzzles emphasize how much classical physics we have yet to learn from the Sun. The physics of solar activity is based on the principles of Newton, Maxwell, Lorentz, Boltzmann, et. al., along with the principles of radiative transfer. In the large, these principles are expressed by magnetohydrodynamics. A brief derivation of the magnetohydrodynamic induction and momentum equations is provided, with a discussion of popular misconceptions.

  6. Darboux transformation for classical acoustic spectral problem

    Directory of Open Access Journals (Sweden)

    M. Rudnev

    2003-09-01

    Full Text Available We study discrete isospectral symmetries for the classical acoustic spectral problem in spatial dimensions one and two by developing a Darboux (Moutard transformation formalism for this problem. The procedure follows steps similar to those for the Schrödinger operator. However, there is no one-to-one correspondence between the two problems. The technique developed enables one to construct new families of integrable potentials for the acoustic problem, in addition to those already known. The acoustic problem produces a nonlinear Harry Dym PDE. Using the technique, we reproduce a pair of simple soliton solutions of this equation. These solutions are further used to construct a new positon solution for this PDE. Furthermore, using the dressing-chain approach, we build a modified Harry Dym equation together with its LA pair. As an application, we construct some singular and nonsingular integrable potentials (dielectric permitivity for the Maxwell equations in a 2D inhomogeneous medium.

  7. The revision of classical stock model

    Institute of Scientific and Technical Information of China (English)

    YE Bai-qing; WANG Hong-li

    2001-01-01

    On the basis of the analysis of classical stock model, according to th e limitation of the model, the article puts forward the revision of classical mo del and enforces the applicability of the stock model.

  8. Pseudoclassical fermionic model and classical solutions

    International Nuclear Information System (INIS)

    We study classical limit of fermionic fields seen as Grassmann variables and deduce the proper quantization prescription using Dirac's method for constrained systems and investigate quantum meaning of classical solutions for the Thirring model. (author)

  9. Classical Electron Theory and Conservation Laws

    OpenAIRE

    Kiessling, Michael K. -H.

    1999-01-01

    It is shown that the traditional conservation laws for total charge, energy, linear and angular momentum, hold jointly in classical electron theory if and only if classical electron spin is included as dynamical degree of freedom.

  10. The revision of classical stock model

    Institute of Scientific and Technical Information of China (English)

    叶柏青; 王洪利

    2001-01-01

    On the basis of the analysis of classical stock model, according to the limitation of the model, the article puts forward the revision of classical model and enforces the applicability of the stock model.

  11. Lagrangian formalism and retarded classical electrodynamics

    OpenAIRE

    Jan, Xavier; Llosa, Josep; Molina, Alfred

    1989-01-01

    Unlike the 1/c2 approximation, where classical electrodynamics is described by the Darwin Lagrangian, here there is no Lagrangian to describe retarded (resp., advanced) classical electrodynamics up to 1/c3 for two-point charges with different masses.

  12. Simulation of molecular transitions using classical trajectories

    Energy Technology Data Exchange (ETDEWEB)

    Donoso, A.; Martens, C. C. [University of California, California (United States)

    2001-03-01

    In the present work, we describe the implementation of a semiclassical method to study physical-chemical processes in molecular systems where electronic state transitions and quantum coherence play a dominant role. The method is based on classical trajectory propagation on the underlying coupled electronic surfaces and is derived from the semiclassical limit of the quantum Liouville equation. Unlike previous classical trajectory-based methods, quantum electronic coherence are treated naturally within this approach as complex weighted trajectory ensembles propagating on the average electronic surfaces. The method is tested on a model problem consisting of one-dimensional motion on two crossing electronic surfaces. Excellent agreement is obtained when compared to the exact results obtained by wave packet propagation. The method is applied to model quantum wave packet interferometry, where two wave packets, differing only in a relative phase, collide in the region where the two electronic surfaces cross. The dependence of the resulting population transfer on the initial relative phase of the wave packets is perfectly captured by our classical trajectory method. Comparison with an alternative method, surface hopping, shows that our approach is appropriate for modelling quantum interference phenomena. [Spanish] En este trabajo se describe la implementacion de un metodo semiclasico para estudiar procesos fisicos-quimicos en sistemas moleculares donde las transiciones entre estados electronicos y las coherencias cuanticas juegan un papel predominante. El metodo se basa en la propagacion de trayectorias clasicas sobre las correspondientes superficies electronicas acopladas y se deriva a partir del limite semiclasico de la ecuacion cuantica de Liouville. A diferencia de metodos previos basados en trayectoria clasica, dentro de este esquema, las coherencias electronicas cuanticas son tratadas de manera natural como ensamble de trayectorias con pesos complejos, moviendose en

  13. Technics of classical and digital photography comparsion

    OpenAIRE

    Kvapilová, Kamila

    2012-01-01

    This bachelor work is aimed at basic principles of taking photos by classical and digital camera. Describes methods for achieving of required photos by digital way and also classical taking photos on cine-film. Compares the technology of classical and digital photography from the beginning, which is getting the camera and accessories. It also describes the construction and control of the camera. Processing of photo compares the quality of digital and classic photo.

  14. Markkinointiviestintäsuunnitelma : Classic Coffee Oy

    OpenAIRE

    Eerola, Laura

    2015-01-01

    Opinnäytetyön aiheena oli laatia markkinointiviestintäsuunnitelma kalenterivuodelle 2016 vuosikellon muodossa, toimintansa jo vakiinnuttaneelle Classic Coffee Oy:lle. Classic Coffee Oy on vuonna 2011 perustettu, Tampereella toimiva kahvila-alan yritys joka tarjoaa lounaskahvilatoiminnan lisäksi laadukkaita konditoria-palveluita, yritys- ja kokoustarjoiluja sekä tilavuokrausta. Classic Coffee Oy:llä on yksi kahvila, Classic Coffee Tampella. Kahvila sijaitsee Tampellassa, Tampereen keskustan vä...

  15. The new-classical contribution to macroeconomics

    OpenAIRE

    D. LAIDLER

    2013-01-01

    This work is devoted to assessing New-Classical ideas, and to asking what of lasting importance this school of macroeconomics has contributed since the early 1970s. It deals in turn with the relationship between New-Classical Economics and Monetarism, the relative explanatory power of these two bodies of doctrine over empirical evidence, and the claims of New-Classical Economics to embody a superior analytic method. The author argues that, although the particular ways in which New-Classical M...

  16. Physiological characteristics of classical ballet.

    Science.gov (United States)

    Schantz, P G; Astrand, P O

    1984-10-01

    The aerobic and anaerobic energy yield during professional training sessions ("classes") of classical ballet as well as during rehearsed and performed ballets has been studied by means of oxygen uptake, heart rate, and blood lactate concentration determinations on professional ballet dancers from the Royal Swedish Ballet in Stockholm. The measured oxygen uptake during six different normal classes at the theatre averaged about 35-45% of the maximal oxygen uptake, and the blood lactate concentration averaged 3 mM (N = 6). During 10 different solo parts of choreographed dance (median length = 1.8 min) representative for moderately to very strenuous dance, an average oxygen uptake (measured during the last minute) of 80% of maximum and blood lactate concentration of 10 mM was measured (N = 10). In addition, heart rate registrations from soloists in different ballets during performance and final rehearsals frequently indicated a high oxygen uptake relative to maximum and an average blood lactate concentration of 11 mM (N = 5). Maximal oxygen uptake, determined in 1971 (N = 11) and 1983 (N = 13) in two different groups of dancers, amounted to on the average 51 and 56 ml X min-1 X kg-1 for the females and males, respectively. In conclusion, classical ballet is a predominantly intermittent type of exercise. In choreographed dance each exercise period usually lasts only a few minutes, but can be very demanding energetically, while during the dancers' basic training sessions, the energy yield is low. PMID:6513765

  17. Classical Black Holes Are Hot

    CERN Document Server

    Curiel, Erik

    2014-01-01

    In the early 1970s it is was realized that there is a striking formal analogy between the Laws of black-hole mechanics and the Laws of classical thermodynamics. Before the discovery of Hawking radiation, however, it was generally thought that the analogy was only formal, and did not reflect a deep connection between gravitational and thermodynamical phenomena. It is still commonly held that the surface gravity of a stationary black hole can be construed as a true physical temperature and its area as a true entropy only when quantum effects are taken into account; in the context of classical general relativity alone, one cannot cogently construe them so. Does the use of quantum field theory in curved spacetime offer the only hope for taking the analogy seriously? I think the answer is `no'. To attempt to justify that answer, I shall begin by arguing that the standard argument to the contrary is not physically well founded, and in any event begs the question. Looking at the various ways that the ideas of "tempe...

  18. Entanglement-Enhanced Classical Communication

    CERN Document Server

    Herrera-Martí, David A

    2008-01-01

    This thesis will be focused on the classical capacity of quantum channels, one of the first areas treated by quantum information theorists. The problem is fairly solved since some years. Nevertheless, this work will give me a reason to introduce a consistent formalism of the quantum theory, as well as to review fundamental facts about quantum non-locality and how it can be used to enhance communication. Moreover, this reflects my dwelling in the spirit of classical information theory, and it is intended to be a starting point towards a thorough study of how quantum technologies can help to shape the future of telecommunications. Whenever it was possible, heuristic reasonings were introduced instead of rigorous mathematical proofs. This finds an explanation in that I am a self-taught neophyte in the field, and just about every time I came across a new concept, physical arguments were always more compelling to me than just maths. The technical content of the thesis is twofold. On one hand, a quadratic classific...

  19. Collection of problems in classical mechanics

    CERN Document Server

    Kotkin, G L; ter Haar, D

    1971-01-01

    Collection of Problems in Classical Mechanics presents a set of problems and solutions in physics, particularly those involving mechanics. The coverage of the book includes 13 topics relevant to classical mechanics, such as integration of one-dimensional equations of motion; the Hamiltonian equations of motion; and adiabatic invariants. The book will be of great use to physics students studying classical mechanics.

  20. Classical approximations of relativistic quantum physics

    OpenAIRE

    Johnson, Glenn Eric

    2016-01-01

    A correspondence of classical to quantum physics studied by Schr\\"{o}\\-dinger and Ehrenfest applies without the necessity of technical conjecture that classical observables are associated with Hermitian Hilbert space operators. This correspondence provides appropriate nonrelativistic classical interpretations to realizations of relativistic quantum physics that are incompatible with the canonical formalism. Using this correspondence, Newtonian mechanics for a $1/r$ potential provides approxim...

  1. Diminuendo: Classical Music and the Academy

    Science.gov (United States)

    Asia, Daniel

    2010-01-01

    How is the tradition of Western classical music faring on university campuses? Before answering this question, it is necessary to understand what has transpired with classical music in the wider culture, as the relationship between the two is so strong. In this article, the author discusses how classical music has taken a big cultural hit in…

  2. Quantum electrodynamics in a classical approximation, 1

    International Nuclear Information System (INIS)

    Quantum electrodynamics is formulated in a classical approximation. A quantum mechanical proper-time is employed as a useful parameter, which enables us to elucidate the relationship between quantum electrodynamics and classical electrodynamics. The classical motion of a charged particle is realized as an asymptotic limit of quantum electrodynamics. (author)

  3. Classical mechanics from Newton to Einstein : a modern introduction

    CERN Document Server

    McCall, Martin

    2011-01-01

    This new edition of Classical Mechanics, aimed at undergraduate physics and engineering students, presents in a user-friendly style an authoritative approach to the complementary subjects of classical mechanics and relativity.   The text starts with a careful look at Newton's Laws, before applying them in one dimension to oscillations and collisions. More advanced applications - including gravitational orbits and rigid body dynamics - are discussed after the limitations of Newton's inertial frames have been highlighted through an exposition of Einstein's Special Relativity. Examples gi

  4. Classical and quantum mechanics via supermetrics in time

    CERN Document Server

    Gozzi, Ennio

    2009-01-01

    Koopman-von Neumann in the 30's gave an operatorial formululation of Classical Mechanics. It was shown later on that this formulation could also be written in a path-integral form. We will label this functional approach as CPI (for classical path-integral) to distinguish it from the quantum mechanical one, which we will indicate with QPI. In the CPI two Grassmannian partners of time make their natural appearance and in this manner time becomes something like a three dimensional supermanifold. Next we introduce a metric in this supermanifold and show that a particular choice of the supermetric reproduces the CPI while a different one gives the QPI.

  5. Classical electromagnetism in a nutshell

    CERN Document Server

    Garg, Anupam

    2012-01-01

    This graduate-level physics textbook provides a comprehensive treatment of the basic principles and phenomena of classical electromagnetism. While many electromagnetism texts use the subject to teach mathematical methods of physics, here the emphasis is on the physical ideas themselves. Anupam Garg distinguishes between electromagnetism in vacuum and that in material media, stressing that the core physical questions are different for each. In vacuum, the focus is on the fundamental content of electromagnetic laws, symmetries, conservation laws, and the implications for phenomena such as radiation and light. In material media, the focus is on understanding the response of the media to imposed fields, the attendant constitutive relations, and the phenomena encountered in different types of media such as dielectrics, ferromagnets, and conductors. The text includes applications to many topical subjects, such as magnetic levitation, plasmas, laser beams, and synchrotrons.

  6. Scientific Realism and Classical Physics

    CERN Document Server

    Singh, Virendra

    2008-01-01

    We recount the successful long career of classical physics, from Newton to Einstein, which was based on the philosophy of scientific realism. Special emphasis is given to the changing status and number of ontological entitities and arguments for their necessity at any time. Newton, initially, began with (i) point particles, (ii) aether, (iii) absolute space and (iv) absolute time. The electromagnetic theory of Maxwell and Faraday introduced `fields' as a new ontological entity not reducible to earlier ones. Their work also unified electricity, magnetism and optics. Repeated failure to observe the motion of earth through aether led Einstein to modify the Newtonian absolute space and time concepts to a fused Minkowski space-time and the removal of aether from basic ontological entities in his special theory of relativity. Later Einstein in his attempts to give a local theory of gravitation was led to further modify flat Minkowski space-time to the curved Riemannian space time. This reduced gravitational phenome...

  7. Classic ballet dancers postural patterns

    Directory of Open Access Journals (Sweden)

    Joseani Paulini Neves Simas

    2008-06-01

    Full Text Available The aim of this study was to evaluate classic ballet practice and its influence on postural patterns and (a identify the most frequent postural changes; (b determine the postural pattern; (c verify the existence of association of practice time and postural changes. The investigation was carried out in two stages: one, description in which 106 dancers participated; the other, causal comparative in which 50 dancers participated; and (a questionnaire; (b a checkerboard; (c postural chart; (d measure tape; (e camera and (f pedoscope were used as instrument. Descriptive and inferential statistics was used for analysis. The results revealed the most frequent postural changes such as hyperlordosis, unleveled shoulders and pronated ankles. Ballet seems to have negative implications in the postural development , affecting especially the vertebral spine, trunk and feet. The practice time was not a parameter to indicate the increase in postural changes. In conclusion, ballet may be associated with postural changes and determining a characteristic postural pattern.

  8. DOE Fundamentals Handbook: Classical Physics

    International Nuclear Information System (INIS)

    The Classical Physics Fundamentals Handbook was developed to assist nuclear facility operating contractors provide operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of physical forces and their properties. The handbook includes information on the units used to measure physical properties; vectors, and how they are used to show the net effect of various forces; Newton's Laws of motion, and how to use these laws in force and motion applications; and the concepts of energy, work, and power, and how to measure and calculate the energy involved in various applications. This information will provide personnel with a foundation for understanding the basic operation of various types of DOE nuclear facility systems and equipment

  9. Classical Concepts in Quantum Programming

    Science.gov (United States)

    Ömer, Bernhard

    2005-07-01

    The rapid progress of computer technology has been accompanied by a corresponding evolution of software development, from hardwired components and binary machine code to high level programming languages, which allowed to master the increasing hardware complexity and fully exploit its potential. This paper investigates, how classical concepts like hardware abstraction, hierarchical programs, data types, memory management, flow of control, and structured programming can be used in quantum computing. The experimental language QCL will be introduced as an example, how elements like irreversible functions, local variables, and conditional branching, which have no direct quantum counterparts, can be implemented, and how nonclassical features like the reversibility of unitary transformation or the nonobservability of quantum states can be accounted for within the framework of a procedural programming language.

  10. A course in classical physics

    CERN Document Server

    Bettini, Alessandro

    2016-01-01

    This first volume covers the mechanics of point particles, gravitation, extended systems (starting from the two-body system), the basic concepts of relativistic mechanics and the mechanics of rigid bodies and fluids. The four-volume textbook, which covers electromagnetism, mechanics, fluids and thermodynamics, and waves and light, is designed to reflect the typical syllabus during the first two years of a calculus-based university physics program. Throughout all four volumes, particular attention is paid to in-depth clarification of conceptual aspects, and to this end the historical roots of the principal concepts are traced. Writings by the founders of classical mechanics, G. Galilei and I. Newton, are reproduced, encouraging students to consult them. Emphasis is also consistently placed on the experimental basis of the concepts, highlighting the experimental nature of physics. Whenever feasible at the elementary level, concepts relevant to more advanced courses in modern physics are included. Each chapter b...

  11. Classical Syllogisms in Logic Teaching

    DEFF Research Database (Denmark)

    Øhrstrøm, Peter; Sandborg-Petersen, Ulrik; Thorvaldsen, Steinar;

    2013-01-01

    test persons have a tendency correctly to assess valid syllogisms as such more often than correctly assessing invalid syllogisms as such. It is also investigated to what extent the students have improved their skills in practical reasoning by attending the logic courses. Finally, some open questions......This paper focuses on the challenges of introducing classical syllogisms in university courses in elementary logic and human reasoning. Using a program written in Prolog+CG, some empirical studies have been carried out involving three groups of students in Denmark; one group of philosophy students...... and two groups of students of informatics. The skills of the students in syllogistic reasoning before and after the logic courses have been studied and are discussed. The empirical observations made with the program make it possible to identify syllogisms which are found difficult by the students, and...

  12. Theoretical physics 1 classical mechanics

    CERN Document Server

    Nolting, Wolfgang

    2016-01-01

    This textbook offers a clear and comprehensive introduction to classical mechanics, one of the core components of undergraduate physics courses. The book starts with a thorough introduction to the mathematical tools needed, to make this textbook self-contained for learning. The second part of the book introduces the mechanics of the free mass point and details conservation principles. The third part expands the previous to mechanics of many particle systems. Finally the mechanics of the rigid body is illustrated with rotational forces, inertia and gyroscope movement. Ideally suited to undergraduate students in their first year, the book is enhanced throughout with learning features such as boxed inserts and chapter summaries, with key mathematical derivations highlighted to aid understanding. The text is supported by numerous worked examples and end of chapter problem sets. About the Theoretical Physics series Translated from the renowned and highly successful German editions, the eight volumes of this series...

  13. Controlling the sense of molecular rotation: classical vs quantum analysis

    CERN Document Server

    Khodorkovsky, Yuri; Hasegawa, Hirokazu; Ohshima, Yasuhiro; Averbukh, Ilya Sh

    2010-01-01

    Recently, it was predicted theoretically and verified experimentally that a pair of delayed and cross-polarized short laser pulses can create molecular ensembles with a well defined sense of rotation (clockwise or counterclockwise). Here we provide a comparative study of the classical and quantum aspects of the underlying mechanism for linear molecules and for symmetric tops, like benzene molecules, that were used for the first experimental demonstration of the effect. Very good quantitative agreement is found between the classical description of the process and the rigorous quantum mechanical analysis at the relevant experimental conditions. Both approaches predict the same optimal values for the delay between pulses and the angle between them, and deliver the same magnitude of the induced oriented angular momentum of the molecular ensemble. As expected, quantum and classical analysis substantially deviate when the delay between pulses is comparable with the period of quantum rotational revivals. However, ti...

  14. Generic emergence of classical features in quantum Darwinism

    Science.gov (United States)

    Brandão, Fernando G. S. L.; Piani, Marco; Horodecki, Paweł

    2015-08-01

    Quantum Darwinism posits that only specific information about a quantum system that is redundantly proliferated to many parts of its environment becomes accessible and objective, leading to the emergence of classical reality. However, it is not clear under what conditions this mechanism holds true. Here we prove that the emergence of classical features along the lines of quantum Darwinism is a general feature of any quantum dynamics: observers who acquire information indirectly through the environment have effective access at most to classical information about one and the same measurement of the quantum system. Our analysis does not rely on a strict conceptual splitting between a system-of-interest and its environment, and allows one to interpret any system as part of the environment of any other system. Finally, our approach leads to a full operational characterization of quantum discord in terms of local redistribution of correlations.

  15. The classical dramatic text and its value in contemporary theatre

    Directory of Open Access Journals (Sweden)

    Nina Žavbi Milojević

    2013-06-01

    Full Text Available This paper deals with the classical dramatic text and its staging in contemporary theatre. Specifically, it aims to show that classical texts can address topical issues. This is illustrated by the example of several stagings of Ivan Cankar’s Hlapci, one of the most influential dramatic texts in Slovene literature. The history of this dramatic text is presented from its first publication and reception to the different stagings in various Slovene professional theatres. The focus is on how the situation in Slovene society is reflected in each examined staging. The drama Hlapci was first staged almost one hundred years ago, when the staging followed closely the dramatic text. However, after 1980 stagings became more independent from the text and more artistic freedom was allowed. The paper will prove that classical dramatic texts are very appropriate for staging in contemporary theatre, especially with an innovative director’s approach.

  16. Representational Realism, Closed Theories and the Quantum to Classical Limit

    CERN Document Server

    de Ronde, Christian

    2016-01-01

    In this paper we discuss the representational realist stance as a pluralist ontic approach to inter-theoretic relationships. Our stance stresses the fact that physical theories require the necessary consideration of a conceptual level of discourse which determines and configures the specific field of phenomena discussed by each particular theory. We will criticize the orthodox line of research which has grounded the analysis about QM in two (Bohrian) metaphysical presuppositions -accepted in the present as dogmas that all interpretations must follow. We will also examine how the orthodox project of "bridging the gap" between the quantum and the classical domains has constrained the possibilities of research, producing only a limited set of interpretational problems which only focus in the justification of "classical reality" and exclude the possibility of analyzing the possibilities of non-classical conceptual representations of QM. The representational realist stance introduces two new problems, namely, the ...

  17. Ensembles on configuration space classical, quantum, and beyond

    CERN Document Server

    Hall, Michael J W

    2016-01-01

    This book describes a promising approach to problems in the foundations of quantum mechanics, including the measurement problem. The dynamics of ensembles on configuration space is shown here to be a valuable tool for unifying the formalisms of classical and quantum mechanics, for deriving and extending the latter in various ways, and for addressing the quantum measurement problem. A description of physical systems by means of ensembles on configuration space can be introduced at a very fundamental level: the basic building blocks are a configuration space, probabilities, and Hamiltonian equations of motion for the probabilities. The formalism can describe both classical and quantum systems, and their thermodynamics, with the main difference being the choice of ensemble Hamiltonian. Furthermore, there is a natural way of introducing ensemble Hamiltonians that describe the evolution of hybrid systems; i.e., interacting systems that have distinct classical and quantum sectors, allowing for consistent descriptio...

  18. Revision of the classical nucleation theory for supersaturated solutions

    CERN Document Server

    Borisenko, Alexander

    2015-01-01

    During the processes of nucleation and growth of a precipitate cluster from a supersaturated solution, the diffusion flux between the cluster and the solution changes the solute concentration near the cluster-solution interface from its average bulk value. This feature affects the rates of attachment and detachment of solute atoms at the interface and, therefore, alters the entire nucleation kinetics. Unless quite obvious, this effect has been ignored in the classical nucleation theory. To illustrate the results of this new approach, for the case of homogeneous nucleation, we calculate the total solubility (including the contribution from heterophase fluctuations) and the nucleation rate as functions of two parameters of the model and compare these results to the classical ones. One can conclude that discrepancies with the classical nucleation theory are great in the diffusion-limited regime, when the bulk diffusion mobility of solute atoms is small compared to the interfacial one, while in the opposite inter...

  19. Hilbert space theory of classical electrodynamics

    Indian Academy of Sciences (India)

    RAJAGOPAL A K; GHOSE PARTHA

    2016-06-01

    Classical electrodynamics is reformulated in terms of wave functions in the classical phase space of electrodynamics, following the Koopman–von Neumann–Sudarshan prescription for classical mechanics on Hilbert spaces sans the superselection rule which prohibits interference effects in classical mechanics. This is accomplished by transforming from a set of commutingobservables in one Hilbert space to another set of commuting observables in a larger Hilbert space. This is necessary to clarify the theoretical basis of the much recent work on quantum-like features exhibited by classical optics. Furthermore, following Bondar et al, {\\it Phys. Rev.} A 88, 052108 (2013), it is pointed out that quantum processes that preserve the positivity or nonpositivity of theWigner function can be implemented by classical optics. This may be useful in interpreting quantum information processing in terms of classical optics.

  20. From reception of classics to outreach: classical reception and American response to war. A case study. Part I

    Directory of Open Access Journals (Sweden)

    Rosanna Lauriola

    2014-03-01

    Full Text Available This paper presents as a case study a discussion pertaining to a peculiar approach that some US scholars have applied to texts of ancient Greek literature, as a response to a specific reality that for decades has been afflicting American society: the timeless experience of war and its aftermath. It is a type of reading and re-usage of some ancient texts that can be regarded as a case of Classical Reception, which also, and almost inevitably, involves Outreach: it in fact provides a service beyond conventional limits to reach out to particular segments of the community. The analysis will be articulated into two parts: the first one will consist of (i a theoretical overview of the status of Classical Reception Studies with a survey of a few cases as a sample of ‘how it works’, and (ii an introduction to the above mentioned approach to classical texts to respond to the reality of modern war, such an approach that turns Classics into an important tool of outreach and therapy. The second part (forthcoming in Acta Scientiarum v.36, n.3 will consist of a detailed discussion of the ‘case study’ in terms of reception, outreach, and therapy, with an attention to the pedagogical discourse, and with a conclusion on a personal note of the author of this paper, based on a related personal experience.

  1. Seismic imaging: From classical to adjoint tomography

    Science.gov (United States)

    Liu, Q.; Gu, Y. J.

    2012-09-01

    Seismic tomography has been a vital tool in probing the Earth's internal structure and enhancing our knowledge of dynamical processes in the Earth's crust and mantle. While various tomographic techniques differ in data types utilized (e.g., body vs. surface waves), data sensitivity (ray vs. finite-frequency approximations), and choices of model parameterization and regularization, most global mantle tomographic models agree well at long wavelengths, owing to the presence and typical dimensions of cold subducted oceanic lithospheres and hot, ascending mantle plumes (e.g., in central Pacific and Africa). Structures at relatively small length scales remain controversial, though, as will be discussed in this paper, they are becoming increasingly resolvable with the fast expanding global and regional seismic networks and improved forward modeling and inversion techniques. This review paper aims to provide an overview of classical tomography methods, key debates pertaining to the resolution of mantle tomographic models, as well as to highlight recent theoretical and computational advances in forward-modeling methods that spearheaded the developments in accurate computation of sensitivity kernels and adjoint tomography. The first part of the paper is devoted to traditional traveltime and waveform tomography. While these approaches established a firm foundation for global and regional seismic tomography, data coverage and the use of approximate sensitivity kernels remained as key limiting factors in the resolution of the targeted structures. In comparison to classical tomography, adjoint tomography takes advantage of full 3D numerical simulations in forward modeling and, in many ways, revolutionizes the seismic imaging of heterogeneous structures with strong velocity contrasts. For this reason, this review provides details of the implementation, resolution and potential challenges of adjoint tomography. Further discussions of techniques that are presently popular in

  2. Construction of exact complex dynamical invariant of a two-dimensional classical system

    Indian Academy of Sciences (India)

    Fakir Chand; S C Mishra

    2006-12-01

    We present the construction of exact complex dynamical invariant of a two-dimensional classical dynamical system on an extended complex space utilizing Lie algebraic approach. These invariants are expected to play a vital role in understanding the complex trajectories of both classical and quantum systems.

  3. A derivation of the Derbenev-Kondratenko formula using semi-classical electrodynamics

    International Nuclear Information System (INIS)

    We present a detailed exposition of the mechanism for the build-up of polarization in electron storage rings. A semi-classical approach is used to derive the rate of growth and asymptotic degree of polarization in an electron storage ring (the Derbenev-Kondratenko formula). Statistical mechanical concepts used to obtain as classical an understanding as possible of this phenomenon. (orig.)

  4. Construction of classical and quantum integrable field models unravelling hidden possibilities

    Indian Academy of Sciences (India)

    Anjan Kundu

    2015-11-01

    Reviewing briefly the concept of classical and quantum integrable systems, we propose an alternative Lax operator approach, leading to quasi-higher-dimensional integrable model, unravelling some hidden dimensions in integrable systems. As an example, we construct a novel integrable quasi-two-dimensional NLS equation at the classical and the quantum levels with intriguing application in rogue wave modelling.

  5. Quantum Electrodynamics Basis of Classical-Field High-Harmonic Generation Theory

    Institute of Scientific and Technical Information of China (English)

    王兵兵; 高靓辉; 傅盘铭; 郭东升; R. R. Freeman

    2001-01-01

    From the nonperturbative quantum electrodynamics theory, we derive the Landau-Dykhne formula which represents the quantum-mechanical formulation of the three-step model. These studies provide a basis for the classical-field approaches to high-order harmonic generation and justify some assumptions used in classical-field modelling.

  6. Religious ecstasy in classical Sufism

    Directory of Open Access Journals (Sweden)

    Göran Ogén

    1982-01-01

    Full Text Available The purpose of this essay is to shed some light on the phenomenon of religious ecstasy as met within Islamic mysticism and there particularly during its classical period. In this case, the expression "classical Sufism" refers to the period of Sufi history from about 850 A.D. until circa 1100 A.D. In the Sufi vocabulary there is even a rather differentiated terminology concerning these ecstatic experiences or states; whether different descriptions of one and the same experience are involved or whether the terms actually describe different experiences is a question that we must set aside for the present. There are, however, Sufis expressing the opinion that these different states of mind are based on one single experience in spite of the difference in terms. A generic term for these experiences or states is not to be found in the Sufi terminology however, so the problem of which of these phenomena must be present in order for ecstasy to be evidenced—or which of them would be sufficient— does not therefore arise for the Sufis. So instead of speaking of religious ecstasy in general, they either refer to the single specific terms in question or else use the plural of one of the words employed to designate one of the terms we include in "religious ecstasy". They thus speak of "ecstasies", mawagid from the singular form wagd—if one should at all attempt a translation of this plural. This plural is a genuine Sufi construction and does not otherwise seem to occur in the Arabic language, except as a later borrowing. Psalmody based on the Koranic vocabulary remains the main procedure for putting oneself in ecstasy. If we add 'and listening to psalmody', we then obtain a fairly satisfactory picture of the external conditions for the Sufis' ecstasy until the eleventh century, when various innovations begin to appear. As far as the darwiš-dance is concerned, it is not until the thirteenth century with Rumi that it becomes transformed from an expression

  7. Rebrightening Phenomenon in Classical Novae

    CERN Document Server

    Kato, Taichi; Maehara, Hiroyuki; Kiyota, Seiichiro

    2009-01-01

    Two classical novae V1493 Aql and V2362 Cyg were known to exhibit unprecedented large-amplitude rebrightening during the late stage of their evolution. We analyzed common properties in these two light curves. We show that these unusual light curves are very well expressed by a combination of power-law decline, omnipresent in fast novae, and exponential brightening. We propose a schematic interpretation of the properties common to these rebrightenings can be a consequence of a shock resulting from a secondary ejection and its breakout in the optically thick nova winds. This interpretation has an advantage in explaining the rapid fading following the rebrightening and the subsequent evolution of the light curve. The exponential rise might reflect emerging light from the shock front, analogous to a radiative precursor in a supernova shock breakout. The consequence of such a shock in the nova wind potentially explains many kinds of unusual phenomena in novae including early-stage variations and potentially dust f...

  8. Classical universes are perfectly predictable!

    Science.gov (United States)

    Schmidt, Jan Hendrik

    I argue that in a classical universe, all the events that ever happen are encoded in each of the universe's parts. This conflicts with a statement which is widely believed to lie at the basis of relativity theory: that the events in a space-time region R determine only the events in R's domain of dependence but not those in other space-time regions. I show how, from this understanding, a new prediction method (which I call the 'Smoothness Method') can be obtained which allows us to predict future events on the basis of local observational data. Like traditional prediction methods, this method makes use of so-called ' ceteris paribus clauses', i.e. assumptions about the unobserved parts of the universe. However, these assumptions are used in a way which enables us to predict the behaviour of open systems with arbitrary accuracy, regardless of the influence of their environment-which has not been achieved by traditional methods. In a sequel to this paper (Schmidt, 1998), I will prove the Uniqueness and Predictability Theorems on which the Smoothness Method is based, and comment in more detail on its mathematical properties.

  9. Classical topology and quantum states

    Indian Academy of Sciences (India)

    A P Balachandran

    2001-02-01

    Any two infinite-dimensional (separable) Hilbert spaces are unitarily isomorphic. The sets of all their self-adjoint operators are also therefore unitarily equivalent. Thus if all self-adjoint operators can be observed, and if there is no further major axiom in quantum physics than those formulated for example in Dirac’s ‘quantum mechanics’, then a quantum physicist would not be able to tell a torus from a hole in the ground. We argue that there are indeed such axioms involving observables with smooth time evolution: they contain commutative subalgebras from which the spatial slice of spacetime with its topology (and with further refinements of the axiom, its - and ∞ - structures) can be reconstructed using Gel’fand–Naimark theory and its extensions. Classical topology is an attribute of only certain quantum observables for these axioms, the spatial slice emergent from quantum physics getting progressively less differentiable with increasingly higher excitations of energy and eventually altogether ceasing to exist. After formulating these axioms, we apply them to show the possibility of topology change and to discuss quantized fuzzy topologies. Fundamental issues concerning the role of time in quantum physics are also addressed.

  10. Nuclear Thermometers for Classical Novae

    CERN Document Server

    Downen, Lori N; José, Jordi; Starrfield, Sumner

    2012-01-01

    Classical novae are stellar explosions occurring in binary systems, consisting of a white dwarf and a main sequence companion. Thermonuclear runaways on the surface of massive white dwarfs, consisting of oxygen and neon, are believed to reach peak temperatures of several hundred million kelvin. These temperatures are strongly correlated with the underlying white dwarf mass. The observational counterparts of such models are likely associated with outbursts that show strong spectral lines of neon in their shells (neon novae). The goals of this work are to investigate how useful elemental abundances are for constraining the peak temperatures achieved during these outbursts and determine how robust "nova thermometers" are with respect to uncertain nuclear physics input. We present updated observed abundances in neon novae and perform a series of hydrodynamic simulations for several white dwarf masses. We find that the most useful thermometers, N/O, N/Al, O/S, S/Al, O/Na, Na/Al, O/P, and P/Al, are those with the s...

  11. Structure of classical affine and classical affine fractional W-algebras

    International Nuclear Information System (INIS)

    We introduce a classical BRST complex (See Definition 3.2.) and show that one can construct a classical affine W-algebra via the complex. This definition clarifies that classical affine W-algebras can be considered as quasi-classical limits of quantum affine W-algebras. We also give a definition of a classical affine fractional W-algebra as a Poisson vertex algebra. As in the classical affine case, a classical affine fractional W-algebra has two compatible λ-brackets and is isomorphic to an algebra of differential polynomials as a differential algebra. When a classical affine fractional W-algebra is associated to a minimal nilpotent, we describe explicit forms of free generators and compute λ-brackets between them. Provided some assumptions on a classical affine fractional W-algebra, we find an infinite sequence of integrable systems related to the algebra, using the generalized Drinfel’d and Sokolov reduction

  12. Digital Classics Outside the Echo-Chamber

    OpenAIRE

    Bodard, Gabriel; Romanello, Matteo

    2016-01-01

    This volume, edited by the organizers of the “Digital Classicist” seminars series, presents research in classical studies, digital classics and digital humanities, bringing together scholarship that addresses the impact of the study of classical antiquity through computational methods on audiences such as scientists, heritage professionals, students and the general public. Within this context, chapters tackle particular aspects, from epigraphy, papyrology and manuscripts, via Greek language, ...

  13. A Drosophila melanogaster model of classic galactosemia

    OpenAIRE

    Kushner, Rebekah F.; Ryan, Emily L.; Sefton, Jennifer M. I.; Rebecca D Sanders; Lucioni, Patricia Jumbo; Kenneth H Moberg; Fridovich-Keil, Judith L.

    2010-01-01

    Classic galactosemia is a potentially lethal disorder that results from profound impairment of galactose-1-phosphate uridylyltransferase (GALT). Despite decades of research, the underlying pathophysiology of classic galactosemia remains unclear, in part owing to the lack of an appropriate animal model. Here, we report the establishment of a Drosophila melanogaster model of classic galactosemia; this is the first whole-animal genetic model to mimic aspects of the patient phenotype. Analogous t...

  14. Exceptional points in quantum and classical dynamics

    CERN Document Server

    Smilga, A V

    2008-01-01

    We notice that, when a quantum system involves exceptional points, i.e. the special values of parameters where the Hamiltonian loses its self-adjointness and acquires the Jordan block structure, the corresponding classical system also exhibits a singular behaviour associated with restructuring of classical trajectories. The system with the crypto-Hermitian Hamiltonian H = (p^2+z^2)/2 -igz^5 and hyper-ellictic classical dynamics is studied in details. Analogies with supersymmetric Yang-Mills dynamics are elucidated.

  15. Exceptional points in quantum and classical dynamics

    Science.gov (United States)

    Smilga, A. V.

    2009-03-01

    We note that when a quantum system involves exceptional points, i.e. the special values of parameters where the Hamiltonian loses its self-adjointness and acquires the Jordan block structure, the corresponding classical system also exhibits singular behaviour associated with the restructuring of classical trajectories. A system with the crypto-Hermitian Hamiltonian H = (p2 + z2)/2 - igz5 and hyper-elliptic classical dynamics is studied in detail. Analogies with supersymmetric Yang-Mills dynamics are elucidated.

  16. Classical Dynamics as Constrained Quantum Dynamics

    OpenAIRE

    Bartlett, Stephen D.; Rowe, David J.

    2002-01-01

    We show that the classical mechanics of an algebraic model are implied by its quantizations. An algebraic model is defined, and the corresponding classical and quantum realizations are given in terms of a spectrum generating algebra. Classical equations of motion are then obtained by constraining the quantal dynamics of an algebraic model to an appropriate coherent state manifold. For the cases where the coherent state manifold is not symplectic, it is shown that there exist natural projectio...

  17. The relation between classical and quantum electrodynamics

    OpenAIRE

    Mario Bacelar Valente

    2012-01-01

    Quantum electrodynamics presents intrinsic limitations in the description of physical processes that make it impossible to recover from it the type of description we have in classical electrodynamics. Hence one cannot consider classical electrodynamics as reducing to quantum electrodynamics and being recovered from it by some sort of limiting procedure. Quantum electrodynamics has to be seen not as an more fundamental theory, but as an upgrade of classical electrodynamics, which permits an ex...

  18. On the tomographic description of classical fields

    International Nuclear Information System (INIS)

    After a general description of the tomographic picture for classical systems, a tomographic description of free classical scalar fields is proposed both in a finite cavity and the continuum. The tomographic description is constructed in analogy with the classical tomographic picture of an ensemble of harmonic oscillators. The tomograms of a number of relevant states such as the canonical distribution, the classical counterpart of quantum coherent states and a new family of so-called Gauss–Laguerre states, are discussed. Finally the Liouville equation for field states is described in the tomographic picture offering an alternative description of the dynamics of the system that can be extended naturally to other fields.

  19. On the tomographic description of classical fields

    Energy Technology Data Exchange (ETDEWEB)

    Ibort, A., E-mail: albertoi@math.uc3m.es [Departamento de Matemáticas, Universidad Carlos III de Madrid, Avda. de la Universidad 30, 28911 Leganés, Madrid (Spain); López-Yela, A., E-mail: alyela@math.uc3m.es [Departamento de Matemáticas, Universidad Carlos III de Madrid, Avda. de la Universidad 30, 28911 Leganés, Madrid (Spain); Man' ko, V.I., E-mail: manko@na.infn.it [P.N. Lebedev Physical Institute, Leninskii Prospect 53, Moscow 119991 (Russian Federation); Marmo, G., E-mail: marmo@na.infn.it [Dipartimento di Scienze Fisiche dell' Università “Federico II” e Sezione INFN di Napoli, Complesso Universitario di Monte S. Angelo, via Cintia, 80126 Naples (Italy); Simoni, A., E-mail: simoni@na.infn.it [Dipartimento di Scienze Fisiche dell' Università “Federico II” e Sezione INFN di Napoli, Complesso Universitario di Monte S. Angelo, via Cintia, 80126 Naples (Italy); Sudarshan, E.C.G., E-mail: bhamathig@gmail.com [Physics Department, Center for Particle Physics, University of Texas, Austin, TX 78712 (United States); Ventriglia, F., E-mail: ventriglia@na.infn.it [Dipartimento di Scienze Fisiche dell' Università “Federico II” e Sezione INFN di Napoli, Complesso Universitario di Monte S. Angelo, via Cintia, 80126 Naples (Italy)

    2012-03-26

    After a general description of the tomographic picture for classical systems, a tomographic description of free classical scalar fields is proposed both in a finite cavity and the continuum. The tomographic description is constructed in analogy with the classical tomographic picture of an ensemble of harmonic oscillators. The tomograms of a number of relevant states such as the canonical distribution, the classical counterpart of quantum coherent states and a new family of so-called Gauss–Laguerre states, are discussed. Finally the Liouville equation for field states is described in the tomographic picture offering an alternative description of the dynamics of the system that can be extended naturally to other fields.

  20. On the tomographic description of classical fields

    CERN Document Server

    Ibort, A; Man'ko, V I; Marmo, G; Simoni, A; Sudarshan, E C G; Ventriglia, F

    2012-01-01

    After a general description of the tomographic picture for classical systems, a tomographic description of free classical scalar fields is proposed both in a finite cavity and the continuum. The tomographic description is constructed in analogy with the classical tomographic picture of an ensemble of harmonic oscillators. The tomograms of a number of relevant states such as the canonical distribution, the classical counterpart of quantum coherent states and a new family of so called Gauss--Laguerre states, are discussed. Finally the Liouville equation for field states is described in the tomographic picture offering an alternative description of the dynamics of the system that can be extended naturally to other fields.

  1. Classical Solution Thermodynamics: A Retrospective View.

    Science.gov (United States)

    Van Ness, H. C.; Abbott, M. M.

    1985-01-01

    Examines topics related to classical solution thermodynamics, considering energy, enthalpy, and the Gibbs function. Applicable mathematical equations are introduced and discussed when appropriate. (JN)

  2. Limitations on Cloning in Classical Mechanics

    OpenAIRE

    Fenyes, Aaron

    2010-01-01

    In this paper, we show that a result precisely analogous to the traditional quantum no-cloning theorem holds in classical mechanics. This classical no-cloning theorem does not prohibit classical cloning, we argue, because it is based on a too-restrictive definition of cloning. Using a less popular, more inclusive definition of cloning, we give examples of classical cloning processes. We also prove that a cloning machine must be at least as complicated as the object it is supposed to clone.

  3. Multipartite classical states and detecting quantum discord

    CERN Document Server

    Chen, Lin; Modi, Kavan; Vacanti, Giovanni

    2010-01-01

    We study various types of multipartite separable states in terms of their inherent classical features. For the two important classes of pseudo-classical, introduced here, and classical states, we provide necessary and sufficient conditions for deciding membership in both which can be checked in polynomial running time. Geometrically, the volume of these states in multipartite state space is found to be measure zero. We also provide a physical criterion for detecting non-classical states based on the commutivity of reduced states following local POVMs performed on individual subsystems.

  4. A projective constrained variational principle for a classical particle with spin

    International Nuclear Information System (INIS)

    A geometric approach for variational principles with constraints is applied to obtain the equations of motion of a classical charged point particle with magnetic moment interacting with an external eletromagnetic field. (Author)

  5. Innovation, markets and uncertainty in Classical Economic Sociology

    Directory of Open Access Journals (Sweden)

    Roberto Herranz González

    2012-04-01

    Full Text Available In this article we address two important dimensions of the sociological approach to markets by such classics as Max Weber, Emile Durkheim, Georg Simmel and Charles Horton Cooley. We observe the way in which they have all analysed two important dimensions: the role of innovation and the role played by institutions. In particular, we look at the role of innovation in the division of labor and the expansion of markets, and analyze the role of institutions in the social construction of markets, the reduction of uncertainty and its performance in the circulation of commodities. The paper shows how they have all adopted an evolutionary and historical perspective and, with the exception of Weber, chosen a dynamic perspective (that is, a critical perspective using the neo-classical approach in economics.

  6. Primary Mediastinal Classical Hodgkin Lymphoma.

    Science.gov (United States)

    Piña-Oviedo, Sergio; Moran, Cesar A

    2016-09-01

    Primary mediastinal Classical Hodgkin lymphoma (CHL) is rare. Nodular sclerosis CHL (NS-CHL) is the most common subtype involving the anterior mediastinum and/or mediastinal lymph nodes. Primary thymic CHL is exceedingly rare. The disease typically affects young women and is asymptomatic in 30% to 50% of patients. Common symptoms include fatigue, chest pain, dyspnea and cough, but vary depending on the location and size of the tumor. B-symptoms develop in 30% of cases. By imaging, primary mediastinal CHL presents as mediastinal widening/mediastinal mass that does not invade adjacent organs but may compress vital structures as bulky disease. Histopathology is the gold standard for diagnosis. Primary mediastinal NS-CHL consists of nodules of polymorphous inflammatory cells surrounded by broad fibrous bands extending from a thickened lymph node capsule. The cellular nodules contain variable numbers of large Hodgkin/Reed-Sternberg cells, required for diagnosis. Primary thymic CHL may exhibit prominent cystic changes. The histopathologic recognition of NS-CHL can be challenging in cases with prominent fibrosis, scant cellularity, artifactual cell distortion, or an exuberant granulomatous reaction. The differential diagnosis includes primary mediastinal non-HLs, mediastinal germ cell tumors, thymoma, and metastatic carcinoma or melanoma to the mediastinum. Distinction from primary mediastinal non-HLs is crucial for adequate therapeutic decisions. Approximately 95% of patients with primary mediastinal CHL will be alive and free of disease at 10 years after treatment with short courses of combined chemoradiotherapy. In this review, we discuss the history, classification, epidemiology, clinicoradiologic features, histopathology, immunohistochemistry, differential diagnosis, and treatment of primary mediastinal CHL. PMID:27441757

  7. Quantum experiments without classical counterparts

    International Nuclear Information System (INIS)

    Full text: We present a generalized and exhaustive method of finding the directions of the quantization axes of the measured eigenstates within experiments which have no classical counterparts. The method relies on a constructive and exhaustive definition of sets of such directions (which we call Kochen-Specker vectors) in a Hilbert space of any dimension as well as of all the remaining vectors of the space. Kochen-Specker vectors are elements of any set of orthonormal states, i.e., vectors in n-dim Hilbert space, Hn, n > 2 to which it is impossible to assign 1s and 0s in such a way that no two mutually orthogonal vectors from the set are both assigned 1 and that not all mutually orthogonal vectors are assigned 0. Our constructive definition of such Kochen-Specker vectors is based on algorithms that generate MMP diagrams corresponding to blocks of orthogonal vectors in Rn, on algorithms that single out those diagrams on which algebraic to 0-1 states cannot be defined, and on algorithms that solve nonlinear equations describing the orthogonalities of the vectors by means of statistically polynomially complex interval analysis and self-teaching programs. The algorithms are limited neither by the number of dimensions nor by the number of vectors. To demonstrate the power of the algorithms, all 4-dim KS vector systems containing up to 24 vectors were generated and described, all 3-dim vector systems containing up to 30 vectors were scanned, and several general properties of KS vectors were found. (author)

  8. NUCLEAR THERMOMETERS FOR CLASSICAL NOVAE

    International Nuclear Information System (INIS)

    Classical novae are stellar explosions occurring in binary systems, consisting of a white dwarf and a main-sequence companion. Thermonuclear runaways on the surface of massive white dwarfs, consisting of oxygen and neon, are believed to reach peak temperatures of several hundred million kelvin. These temperatures are strongly correlated with the underlying white dwarf mass. The observational counterparts of such models are likely associated with outbursts that show strong spectral lines of neon in their shells (neon novae). The goals of this work are to investigate how useful elemental abundances are for constraining the peak temperatures achieved during these outbursts and determine how robust 'nova thermometers' are with respect to uncertain nuclear physics input. We present updated observed abundances in neon novae and perform a series of hydrodynamic simulations for several white dwarf masses. We find that the most useful thermometers, N/O, N/Al, O/S, S/Al, O/Na, Na/Al, O/P, and P/Al, are those with the steepest monotonic dependence on peak temperature. The sensitivity of these thermometers to thermonuclear reaction rate variations is explored using post-processing nucleosynthesis simulations. The ratios N/O, N/Al, O/Na, and Na/Al are robust, meaning they are minimally affected by uncertain rates. However, their dependence on peak temperature is relatively weak. The ratios O/S, S/Al, O/P, and P/Al reveal strong dependences on temperature and the poorly known 30P(p, γ)31S rate. We compare our model predictions to neon nova observations and obtain the following estimates for the underlying white dwarf masses: 1.34-1.35 M ☉ (V838 Her), 1.18-1.21 M ☉ (V382 Vel), ≤1.3 M ☉ (V693 CrA), ≤1.2 M ☉ (LMC 1990 no. 1), and ≤1.2 M ☉ (QU Vul).

  9. Outcome Research in Classical Psychodrama.

    Science.gov (United States)

    Kellermann, Peter Felix

    1987-01-01

    Examines various aspects of psychodrama outcome research and summarizes in tabular form 23 outcome studies published between 1952 and 1985, interpreting them as a whole. Concludes that psychodrama constitutes a valid alternative to other therapeutic approaches, especially in promoting behavior change in adjustment, antisocial, and related…

  10. A classical primer for QCD

    International Nuclear Information System (INIS)

    A basic primer for QCD is presented using a semiclassical approach to the colour Maxwell equations. The non-Abelian nature of colour symmetry and the violation of superposition by colour fields is compared with QED. A simple discussion of asymptotic freedom is also presented. (author)

  11. MUSIC EDUCATION AND TASTE FORMING OF CLASSICAL MUSIC STYLE: CASE STUDY IN CULTURAL INSTITUTIONKARTA PUSTAKA YOGYAKARTA INDONESIA

    Directory of Open Access Journals (Sweden)

    Inggit Sitowati

    2014-06-01

    Full Text Available Karta Pustaka is one of the cultural institutions in Yogyakarta, which has a classical music concert program. The purpose of this study is to describe the history of Karta Pustaka and organizing classical music concerts, the concert format, and its role in supporting classical music education in Yogyakarta. The method used in this study is qualitative research with historical and musicological approach.The data are collected by using interviews, documents and observations. Data were analyzed using qualitative descriptions technicians. The results showed that Karta Pustaka as cultural institution has become a classical musicmedia which has a supporting role in classical music education in Yogyakarta. The classical music concert program and classical music workshop held by Karta Pustaka information and knowledge for the students and people of musical art in Yogyakarta. In addition Karta Pustaka also acts as a forming media and the development of consumer’s classical music tastes and styles in Yogyakarta.

  12. On Covariant Poisson Brackets in Classical Field Theory

    OpenAIRE

    Forger, Michael; Salles, Mário O.

    2015-01-01

    How to give a natural geometric definition of a covariant Poisson bracket in classical field theory has for a long time been an open problem - as testified by the extensive literature on "multisymplectic Poisson brackets", together with the fact that all these proposals suffer from serious defects. On the other hand, the functional approach does provide a good candidate which has come to be known as the Peierls - De Witt bracket and whose construction in a geometrical setting is now well unde...

  13. Chain ladder method: Bayesian bootstrap versus classical bootstrap

    OpenAIRE

    Peters, Gareth W.; Mario V. W\\"uthrich; Shevchenko, Pavel V.

    2010-01-01

    The intention of this paper is to estimate a Bayesian distribution-free chain ladder (DFCL) model using approximate Bayesian computation (ABC) methodology. We demonstrate how to estimate quantities of interest in claims reserving and compare the estimates to those obtained from classical and credibility approaches. In this context, a novel numerical procedure utilising Markov chain Monte Carlo (MCMC), ABC and a Bayesian bootstrap procedure was developed in a truly distribution-free setting. T...

  14. Semi-classical beam cooling in an intense laser pulse

    OpenAIRE

    Yoffe, Samuel R.; Kravets, Yevgen; Noble, Adam; Jaroszynski, Dino A.

    2014-01-01

    We present a novel technique for studying the evolution of a particle distribution using single particle dynamics such that the distribution can be accurately reconstructed using fewer particles than existing approaches. To demonstrate this, the Landau-Lifshiftz description of radiation reaction is adapted into a semi-classical model, for which the Vlasov equation is intractable. Collision between an energetic electron bunch and high-intensity laser pulses are then compared using the two theo...

  15. Conservative error measures for classical and quantum metrology

    CERN Document Server

    Tsang, Mankei

    2016-01-01

    The classical and quantum Cram\\'er-Rao bounds have become standard measures of parameter-estimation uncertainty for a variety of sensing and imaging applications in recent years, but their assumption of unbiased estimators potentially undermines their significance as fundamental limits. In this note we advocate a Bayesian approach with Van Trees inequalities and worst-case priors to overcome the problem. Applications to superlocalization and gravitational-wave parameter estimation are discussed.

  16. Classical and semiclassical aspects of chemical dynamics

    International Nuclear Information System (INIS)

    Tunneling in the unimolecular reactions H2C2 → HC2H, HNC → HCN, and H2CO → H2 + CO is studied with a classical Hamiltonian that allows the reaction coordinate and transverse vibrational modes to be considered directly. A combination of classical perturbation theory and the semiclassical WKB method allows tunneling probabilities to be obtained, and a statistical theory (RRKM) is used to construct rate constants for these reactions in the tunneling regime. In this fashion, it is found that tunneling may be important, particularly for low excitation energies. Nonadiabatic charge transfer in the reaction Na + I → Na + + I- is treated with classical trajectories based on a classical Hamiltonian that is the analogue of a quantum matrix representation. The charge transfer cross section obtained is found to agree reasonably well with the exact quantum results. An approximate semiclassical formula, valid at high energies, is also obtained. The interaction of radiation and matter is treated from a classical viewpoint. The excitation of an HF molecule in a strong laser is described with classical trajectories. Quantum mechanical results are also obtained and compared to the classical results. Although the detailed structure of the pulse time averaged energy absorption cannot be reproduced classically, classical mechanics does predict the correct magnitude of energy absorption, as well as certain other qualitative features. The classical behavior of a nonrotating diatomic molecule in a strong laser field is considered further, by generating a period advance map that allows the solution over many periods of oscillation of the laser to be obtained with relative ease. Classical states are found to form beautiful spirals in phase space as time progresses. A simple pendulum model is found to describe the major qualitative features

  17. Introduction to classical and quantum field theory

    International Nuclear Information System (INIS)

    This is the first introductory textbook on quantum field theory to be written from the point of view of condensed matter physics. As such, it presents the basic concepts and techniques of statistical field theory, clearly explaining how and why they are integrated into modern quantum (and classical) field theory, and includes the latest developments. Written by an expert in the field, with a broad experience in teaching and training, it manages to present such substantial topics as phases and phase transitions or solitons and instantons in an accessible and concise way. Divided into three parts, the first part covers fundamental physics and the mathematics background needed by students in order to enter the field, while the second part introduces more advanced concepts and techniques. Part III discusses applications of quantum field theory to a few basic problems. The emphasis here lies on how modern concepts of quantum field theory are embedded in these approaches, and also on the limitations of standard quantum field theory techniques in facing, 'real' physics problems. Throughout there are numerous end-of-chapter problems, and a free solutions manual is available for lecturers. (orig.)

  18. Experience-based classical RCM at Ginna

    International Nuclear Information System (INIS)

    Rochester Gas ampersand Electric Company began a comprehensive maintenance improvement program for its Ginna station in early 1985. The program includes all activities and functions related to maintenance and has as its focal point, a plantwide, experience-based, classical reliability-centered maintenance (RCM) program. Although performance of the now nearly 20-year-old plant has been outstanding, aging equipment and rising maintenance burdens pose a serious threat to continued exemplary performance. Ginna's RCM program began with a carefully structured system selection process to focus project resources on those systems most important to continued safe and economical operation. The process began with definition of tangible and intangible system attributes and weighting factors. Each system was then rated separately in a two-step process designed to reduce subjective bias. Twenty systems were selected for study. Additional systems may be added at a later date. The analytical approaches discussed address the identification of failure modes and effects, criticality, and development of RCM tasks to prevent failure for most common system elements. In reality, the depth and focus of the analysis is usually limited to short-term degradation mechanisms or those already experienced, either at Ginna or somewhere else in the industry. To completely address all potential failure mechanisms, additional evaluations are performed specifically for long-term age-related degradation in critical components

  19. Relativistic and separable classical hamiltonian particle dynamics

    International Nuclear Information System (INIS)

    We show within the Hamiltonian formalism the existence of classical relativistic mechanics of N scalar particles interacting at a distance which satisfies the requirements of Poincare invariance, separability, world-line invariance and Einstein causality. The line of approach which is adopted here uses the methods of the theory of systems with constraints applied to manifestly covariant systems of particles. The study is limited to the case of scalar interactions remaining weak in the whole phase space and vanishing at large space-like separation distances of the particles. Poincare invariance requires the inclusion of many-body, up to N-body, potentials. Separability requires the use of individual or two-body variables and the construction of the total interaction from basic two-body interactions. Position variables of the particles are constructed in terms of the canonical variables of the theory according to the world-line invariance condition and the subsidiary conditions of the non-relativistic limit and separability. Positivity constraints on the interaction masses squared of the particles ensure that the velocities of the latter remain always smaller than the velocity of light

  20. Bioinformatics and Classical Literary Study

    OpenAIRE

    Chaudhuri, Pramit; Dexter, Joseph P.

    2016-01-01

    This paper describes a collaborative project between classicists, quantitative biologists, and computer scientists to apply ideas and methods drawn from the sciences to the study of literature. A core goal of the project is the use of computational biology, natural language processing, and machine learning techniques to investigate intertextuality, reception, and related phenomena of literary significance. As a case study in our approach, here we describe the use of sequence alignment, a comm...

  1. Classical transport in disordered systems

    Science.gov (United States)

    Papaioannou, Antonios

    This thesis reports on the manifestation of structural disorder on molecular transport and it consists of two parts. Part I discusses the relations between classical transport and the underlying structural complexity of the system. Both types of molecular diffusion, namely Gaussian and non- Gaussian are presented and the relevant time regimes are discussed. In addition the concept of structural universality is introduced and connected with the diffusion metrics. One of the most robust techniques for measuring molecular mean square displacements is magnetic resonance. This method requires encoding and subsequently reading out after an experimentally controlled time, a phase φ to the spins using magnetic field gradients. The main limitation for probing short diffusion lengths L(t) ˜ 1micro m with magnetic resonance is the requirement to encode and decode the phase φ in very short time intervals. Therefore, to probe such displacements a special probe was developed equipped with a gradient coil capable of delivering magnetic field gradients of approximately 90 G/cmA . The design of the probe is reported. Part I also includes a discussion of experiments of transport in two qualitatively different disordered phantoms and reports on a direct observation of universality in one-dimension. The results reveal the universal power law scaling of the diffusion coefficient at the long-time regime and illustrate the essence of structural universality by experimentally determining the structure correlation function of the phantoms. In addition, the scaling of the diffusive permeability of the phantoms with respect to the pore size is investigated. Additional work presented includes a detailed study of adsorption of methane gas in Vycor disordered glass. The techniques described in Part I of this thesis are widely used for measuring structural parameters of porous media, such as the surface-to-volume ratio or diffusive permeability. Part II of this thesis discusses the

  2. Black Hole evaporation in semi-classical approach

    OpenAIRE

    Sawayama, Shintaro

    2011-01-01

    As well as known, the black hole evaporation problem is famous problem. Because the S.W.Hawking found the black holes emit light at the future null infinity as a thermal radiation \\cite{H}, we think that the black holes may be vanish. However, to prove this problem, we should solve field equation, i.e. forth order partial differential equations \\cite{Ford}\\cite{BD}. However, we can find a method to solve this equation, and we could prove that the black holes finally vanish. To solve this prob...

  3. A Statistical Approach to Modeling Indian Classical Music Performance

    CERN Document Server

    Chakraborty, Soubhik; Roy, Sayan; Chauhan, Shivee; Tripathy, Sanjaya Shankar; Mahto, Kartik

    2008-01-01

    A raga is a melodic structure with fixed notes and a set of rules characterizing a certain mood endorsed through performance. By a vadi swar is meant that note which plays the most significant role in expressing the raga. A samvadi swar similarly is the second most significant note. However, the determination of their significance has an element of subjectivity and hence we are motivated to find some truths through an objective analysis. The paper proposes a probabilistic method of note detection and demonstrates how the relative frequency (relative number of occurrences of the pitch) of the more important notes stabilize far more quickly than that of others. In addition, a count for distinct transitory and similar looking non-transitory (fundamental) frequency movements (but possibly embedding distinct emotions!) between the notes is also taken depicting the varnalankars or musical ornaments decorating the notes and note sequences as rendered by the artist. They reflect certain structural properties of the r...

  4. Cleaning graphene : a first quantum/classical molecular dynamics approach

    OpenAIRE

    Delfour, L.; Davydova, A.; Despiau-Pujo, E.; Cunge, G; Graves, D. B.; Magaud, L.

    2015-01-01

    Graphene outstanding properties created a huge interest in the condensed matter community and unprecedented fundings at the international scale in the hope of application developments. Recently, there have been several reports of incomplete removal of the polymer resists used to transfer as-grown graphene from one substrate to another, resulting in altered graphene transport properties. Finding a large-scale solution to clean graphene from adsorbed residues is highly desirable and one promisi...

  5. Impacts of Idealism on Educational Administration and Classical Management Approaches

    OpenAIRE

    Erkılıç, Turan Akman; Himmetoğlu, Beyza

    2015-01-01

    The discussions on the effect of idealism on education and educational administration are broad; however, academic studies are limited. In a sense, it can be observed that the literature on idealism as one of the first outcomes of thinking, perspectives on life and systematic thought is limited in that there is a lack of studies investigating its reflection on educational administration and institutional administration processes. Therefore, it is essential to examine the reflections of ideali...

  6. Handbook of Optimization From Classical to Modern Approach

    CERN Document Server

    Snášel, Václav; Abraham, Ajith

    2013-01-01

    Optimization problems were and still are the focus of mathematics from antiquity to the present. Since the beginning of our civilization, the human race has had to confront numerous technological challenges, such as finding the optimal solution of various problems including control technologies, power sources construction, applications in economy, mechanical engineering and energy distribution amongst others. These examples encompass both ancient as well as modern technologies like the first electrical energy distribution network in USA etc. Some of the key principles formulated in the middle ages were done by Johannes Kepler (Problem of the wine barrels), Johan Bernoulli (brachystochrone problem), Leonhard Euler (Calculus of Variations), Lagrange (Principle multipliers), that were formulated primarily in the ancient world and are of a geometric nature. In the beginning of the modern era, works of L.V. Kantorovich and G.B. Dantzig (so-called linear programming) can be considered amongst others. This book disc...

  7. Classical data compression with quantum side information

    OpenAIRE

    Devetak, I.; Winter, A.

    2002-01-01

    The problem of classical data compression when the decoder has quantum side information at his disposal is considered. This is a quantum generalization of the classical Slepian-Wolf theorem. The optimal compression rate is found to be reduced from the Shannon entropy of the source by the Holevo information between the source and side information.

  8. Modal analysis of a classical guitar

    Science.gov (United States)

    Cohen, David; Rossing, Thomas D.

    2002-11-01

    Using holographic interferometry, we have determined the modes of vibration of a classical guitar (by the first author) having an asymmetrically-braced top plate and a crossed braced back of unique design. The vibrational modes and acoustical properties are compared with other classical guitars.

  9. Dispersions in Semi-Classical Dynamics

    International Nuclear Information System (INIS)

    Dispersions around mean values of one-body observables are obtained by restoring classical many-body correlations in Vlasov and Landau-Vlasov dynamics. The method is applied to the calculation of fluctuations in mass, charge and linear momentum in heavy-ion collisions. Results are compared to those obtained by the Balian-Veneroni variational principle in semi-classical approximation

  10. The Dance of Spain: Classical Folkloric Flamenco.

    Science.gov (United States)

    Gallant, Clifford J.

    A text on the classical and folk dance of Spain includes a pretest, provided in both English and Spanish; text about the dance in general and the dance of Spain, both classical and folkloric; tests on the text, in both English and Spanish; more specific readings about the traditions of flamenco, castanets, and "el jaleo"; a glossary of flamenco…

  11. Classical and Quantum-Mechanical State Reconstruction

    Science.gov (United States)

    Khanna, F. C.; Mello, P. A.; Revzen, M.

    2012-01-01

    The aim of this paper is to present the subject of state reconstruction in classical and in quantum physics, a subject that deals with the experimentally acquired information that allows the determination of the physical state of a system. Our first purpose is to explain a method for retrieving a classical state in phase space, similar to that…

  12. Introducing quantum effects in classical theories

    CERN Document Server

    Fabris, J C; Rodrigues, D C; Daouda, M H

    2015-01-01

    In this paper, we explore two different ways of implementing quantum effects in a classical structure. The first one is through an external field. The other one is modifying the classical conservation laws. In both cases, the consequences for the description of the evolution of the universe are discussed.

  13. Copies of classical logic in intuitionistic logic

    OpenAIRE

    Gaspar, Jaime

    2012-01-01

    Classical logic (the logic of non-constructive mathematics) is stronger than intuitionistic logic (the logic of constructive mathematics). Despite this, there are copies of classical logic in intuitionistic logic. All copies usually found in the literature are the same. This raises the question: is the copy unique? We answer negatively by presenting three different copies.

  14. Classical Hamiltonian Dynamics and Lie Group Algebras

    CERN Document Server

    Aycock, B; Silverberg, J L; Widom, A

    2008-01-01

    The classical Hamilton equations of motion yield a structure sufficiently general to handle an almost arbitrary set of ordinary differential equations. Employing elementary algebraic methods, it is possible within the Hamiltonian structure to describe many physical systems exhibiting Lie group symmetries. Elementary examples include magnetic moment precession and the mechanical orbits of color charged particles in classical non-abelian chromodynamics.

  15. Classical Swine Fever Virus-Rluc Replicons

    DEFF Research Database (Denmark)

    Risager, Peter Christian; Belsham, Graham J.; Rasmussen, Thomas Bruun

    Classical swine fever virus (CSFV) is the etiologic agent of the severe porcine disease, classical swine fever. Unraveling the molecular determinants of efficient replication is crucial for gaining proper knowledge of the pathogenic traits of this virus. Monitoring the replication competence within...

  16. The Zoology of the classical islamic culture

    DEFF Research Database (Denmark)

    Provencal, Philippe; Aarab, Ahmed

    2014-01-01

    This article brings a survey of research on the science of zoology in the Classical Arabic/Islamic Culture as revealed in texts on this subject written in Classical Arabic from the second half of the 8th century to the 15th century A.D. In the light of recent research and by use of examples from...

  17. Classic and Hard-Boiled Detective Fiction.

    Science.gov (United States)

    Reilly, John M.

    Through an analysis of several stories, this paper defines the similarities and differences between classic and hard-boiled detective fiction. The characters and plots of three stories are discussed: "The Red House" by A. A. Milne; "I, The Jury" by Mickey Spillane; and "League of Frightened Men" by Rex Stout. The classic detective story is defined…

  18. Tarnished Gold: Classical Music in America

    Science.gov (United States)

    Asia, Daniel

    2010-01-01

    A few articles have appeared recently regarding the subject of the health of classical music (or more broadly, the fine arts) in America. These include "Classical Music's New Golden Age," by Heather Mac Donald, in the "City Journal" and "The Decline of the Audience," by Terry Teachout, in "Commentary." These articles appeared around the time of…

  19. Classical decoherence in a nanomechanical resonator

    Science.gov (United States)

    Maillet, O.; Vavrek, F.; Fefferman, A. D.; Bourgeois, O.; Collin, E.

    2016-07-01

    Decoherence is an essential mechanism that defines the boundary between classical and quantum behaviours, while imposing technological bounds for quantum devices. Little is known about quantum coherence of mechanical systems, as opposed to electromagnetic degrees of freedom. But decoherence can also be thought of in a purely classical context, as the loss of phase coherence in the classical phase space. Indeed the bridge between quantum and classical physics is under intense investigation, using, in particular, classical nanomechanical analogues of quantum phenomena. In the present work, by separating pure dephasing from dissipation, we quantitatively model the classical decoherence of a mechanical resonator: through the experimental control of frequency fluctuations, we engineer artificial dephasing. Building on the fruitful analogy introduced between spins/quantum bits and nanomechanical modes, we report on the methods available to define pure dephasing in these systems, while demonstrating the intrinsic almost-ideal properties of silicon nitride beams. These experimental and theoretical results, at the boundary between classical nanomechanics and quantum information fields, are prerequisite in the understanding of decoherence processes in mechanical devices, both classical and quantum.

  20. Quantum Communication Attacks on Classical Cryptographic Protocols

    DEFF Research Database (Denmark)

    Damgård, Ivan Bjerre

    , one can show that the protocol remains secure even under such an attack. However, there are also cases where the honest players are quantum as well, even if the protocol uses classical communication. For instance, this is the case when classical multiparty computation is used as a “subroutine......” in quantum multiparty computation. Furthermore, in the future, players in a protocol may employ quantum computing simply to improve efficiency of their local computation, even if the communication is supposed to be classical. In such cases, it no longer seems clear that a quantum adversary must be limited......In the literature on cryptographic protocols, it has been studied several times what happens if a classical protocol is attacked by a quantum adversary. Usually, this is taken to mean that the adversary runs a quantum algorithm, but communicates classically with the honest players. In several cases...

  1. Emergence of classical theories from quantum mechanics

    CERN Document Server

    Hajicek, Petr

    2012-01-01

    Three problems stand in the way of deriving classical theories from quantum mechanics: those of realist interpretation, of classical properties and of quantum measurement. Recently, we have identified some tacit assumptions that lie at the roots of these problems. Thus, a realist interpretation is hindered by the assumption that the only properties of quantum systems are values of observables. If one simply postulates the properties to be objective that are uniquely defined by preparation then all difficulties disappear. As for classical properties, the wrong assumption is that there are arbitrarily sharp classical trajectories. It turns out that fuzzy classical trajectories can be obtained from quantum mechanics by taking the limit of high entropy. Finally, standard quantum mechanics implies that any registration on a quantum system is disturbed by all quantum systems of the same kind existing somewhere in the universe. If one works out systematically how quantum mechanics must be corrected so that there is ...

  2. Organic Hybridization,Harmonious Coexistence An Eco-translatological Approach to English Translation of Chinese Classical Poetry in the Context of Globalization%有机杂合,和谐共生全球化背景下古诗英译的生态翻译取向

    Institute of Scientific and Technical Information of China (English)

    段丽

    2014-01-01

    In the ecological view,translation carries with it the mission of upholding diversity and mul-tiplicity and promoting the harmonious development of world cultural ecology.Based on this,this paper proposes an eco-translatological approach to English translation of Chinese classical poetry.It elaborates this approach from hybridization and highlighting difference.Highlighting difference emphasizes the trans-lation's original heterogeneity on the basis of maximum understandability so as to make the reader experi-ence the artistic charm of the original poetry and the heterogeneity and enrich the target language culture. Hybridization tries to retain the image of the original poem with the Chinese syntactic structure while skill-fully mixing classical poetry expression form with the target language expression.Using a new language form,hybridization preferably reproduces the original meaning of the poem and artistic conception and con-veys the original cultural essence of the poem.%从生态视角来看,翻译就是要维护语言多元和文化多样性,促进世界文化和谐生态发展。在此基础上,提出古诗英译的生态翻译取向,从求异与杂合两种译介途径进行论证。求异就是强调译文在可理解性基础上最大限度保留原文异质性,使译文读者在体验差异性的同时体味原诗的艺术魅力,丰富译语文化;杂合乃一方面尽可能保留原诗的意象与汉语句法结构,另一方面巧妙地将古诗表达形式与译语表达形式融合,以一种新语言形式进入译语,以便更好地再现原诗的意蕴和意境,传达原诗的文化精髓。

  3. On the criticism to the classical method

    Directory of Open Access Journals (Sweden)

    Cláudio Gontijo

    2000-01-01

    Full Text Available This article addresses the most common criticisms on the "surplus approach''. It shows that the classical method avoids the excess of abstraction of neoclassical general equilibrium theory, which produces models that have no empirical content, and the lack of abstraction of the post-Keynesian school which does not accept equilibrium. Taking reality as a chain of accidental events connected in a dynamic logical process, the neoclassical school conceives market prices as empirical phenomena that nevertheless gravitate around moving equilibrium prices thanks to the adjustment mechanisms. Though this gravitation process should be conceived as an axiom of logic, it can be modeled in such a way as to produce stable results under quite reasonable assumptions. Finally, it shows that the classical concept of competition can be used for explaining profit rate differentials, which are the bases of the theory of oligopoly pricing.Este artigo analisa as principais críticas à "abordagem do excedente econômico''. Ele mostra que o método clássico evita o excesso de abstração da teoria neoclássica do equilíbrio geral, que produz modelos sem conteúdo empírico, e a falta de abstração da escola pós-keynesiana, que não aceita o conceito de equilíbrio. Considerando a realidade como uma cadeia de eventos acidentais conectados num processo dinâmico, a escola clássica concebe os preços de mercado como fenômenos empíricos que gravitam em torno dos preços de equilíbrio graças aos mecanismos de ajustamento. Ainda que o processo de gravitação deva ser concebido como um axioma lógico, ele pode ser modelado de forma a produzir resultados estáveis sob hipóteses bastante razoáveis. Finalmente, o artigo mostra que o conceito clássico de concorrência pode ser utilizado para explicar os diferenciais de taxa de lucro que representam a base da teoria de preços em regime de oligopólio.

  4. Lie Groupoids in Classical Field Theory I: Noether's Theorem

    CERN Document Server

    Costa, Bruno T; Pêgas, Luiz Henrique P

    2015-01-01

    In the two papers of this series, we initiate the development of a new approach to implementing the concept of symmetry in classical field theory, based on replacing Lie groups/algebras by Lie groupoids/algebroids, which are the appropriate mathematical tools to describe local symmetries when gauge transformations are combined with space-time transformations. Here, we outline the basis of the program and, as a first step, show how to (re)formulate Noether's theorem about the connection between symmetries and conservation laws in this approach.

  5. Classical Ising chain in transverse field

    International Nuclear Information System (INIS)

    The spin 12 Ising chain in transverse field is considered the prototypical system for quantum phase transitions. However, very little is apparently known in literature about its classical counterpart, not to be confused with the standard classical Ising model: while the latter is constructed from classical discrete variables, the model we consider is a chain of classical vectors of modulus 1, interacting via an Ising-like Hamiltonian. When an uniform field is applied perpendicular to the exchange interaction, both the quantum model and its classical counterpart get to be characterized by a critical field separating a ferromagnetically ordered state of minimal energy from a paramagnetic one. The properties of the classical model, and especially the behaviour of the correlation length, are investigated at low temperature around the critical field and compared with those of the quantum model, in order to single out the role played by quantum and classical fluctuations at finite temperature; the possibility to experimentally observe peculiar quantum critical effects in Ising spin chains is discussed

  6. Inverse problems in classical and quantum physics

    International Nuclear Information System (INIS)

    The subject of this thesis is in the area of Applied Mathematics known as Inverse Problems. Inverse problems are those where a set of measured data is analysed in order to get as much information as possible on a model which is assumed to represent a system in the real world. We study two inverse problems in the fields of classical and quantum physics: QCD condensates from tau-decay data and the inverse conductivity problem. Despite a concentrated effort by physicists extending over many years, an understanding of QCD from first principles continues to be elusive. Fortunately, data continues to appear which provide a rather direct probe of the inner workings of the strong interactions. We use a functional method which allows us to extract within rather general assumptions phenomenological parameters of QCD (the condensates) from a comparison of the time-like experimental data with asymptotic space-like results from theory. The price to be paid for the generality of assumptions is relatively large errors in the values of the extracted parameters. Although we do not claim that our method is superior to other approaches, we hope that our results lend additional confidence to the numerical results obtained with the help of methods based on QCD sum rules. EIT is a technology developed to image the electrical conductivity distribution of a conductive medium. The technique works by performing simultaneous measurements of direct or alternating electric currents and voltages on the boundary of an object. These are the data used by an image reconstruction algorithm to determine the electrical conductivity distribution within the object. In this thesis, two approaches of EIT image reconstruction are proposed. The first is based on reformulating the inverse problem in terms of integral equations. This method uses only a single set of measurements for the reconstruction. The second approach is an algorithm based on linearisation which uses more then one set of measurements. A

  7. Inverse problems in classical and quantum physics

    Energy Technology Data Exchange (ETDEWEB)

    Almasy, A.A.

    2007-06-29

    The subject of this thesis is in the area of Applied Mathematics known as Inverse Problems. Inverse problems are those where a set of measured data is analysed in order to get as much information as possible on a model which is assumed to represent a system in the real world. We study two inverse problems in the fields of classical and quantum physics: QCD condensates from tau-decay data and the inverse conductivity problem. Despite a concentrated effort by physicists extending over many years, an understanding of QCD from first principles continues to be elusive. Fortunately, data continues to appear which provide a rather direct probe of the inner workings of the strong interactions. We use a functional method which allows us to extract within rather general assumptions phenomenological parameters of QCD (the condensates) from a comparison of the time-like experimental data with asymptotic space-like results from theory. The price to be paid for the generality of assumptions is relatively large errors in the values of the extracted parameters. Although we do not claim that our method is superior to other approaches, we hope that our results lend additional confidence to the numerical results obtained with the help of methods based on QCD sum rules. EIT is a technology developed to image the electrical conductivity distribution of a conductive medium. The technique works by performing simultaneous measurements of direct or alternating electric currents and voltages on the boundary of an object. These are the data used by an image reconstruction algorithm to determine the electrical conductivity distribution within the object. In this thesis, two approaches of EIT image reconstruction are proposed. The first is based on reformulating the inverse problem in terms of integral equations. This method uses only a single set of measurements for the reconstruction. The second approach is an algorithm based on linearisation which uses more then one set of measurements. A

  8. Tomograms in the quantum-classical transition

    Energy Technology Data Exchange (ETDEWEB)

    Man' ko, V.I. [P.N. Lebedev Physical Institute, Leninskii Prospect 53, Moscow 119991 (Russian Federation)]. E-mail: manko@na.infn.it; Marmo, G. [Dipartimento di Scienze Fisiche dell' Universita Federico II e Sezione INFN di Napoli, Complesso Universitario di Monte S. Angelo, I-80126 Naples (Italy)]. E-mail: marmo@na.infn.it; Simoni, A. [Dipartimento di Scienze Fisiche dell' Universita Federico II e Sezione INFN di Napoli, Complesso Universitario di Monte S. Angelo, I-80126 Naples (Italy)]. E-mail: simoni@na.infn.it; Stern, A. [Department of Physics, University of Alabama, Tuscaloosa, AL 35487 (United States)]. E-mail: astern@bama.ua.edu; Ventriglia, F. [Dipartimento di Scienze Fisiche dell' Universita Federico II e Sezione INFN di Napoli, Complesso Universitario di Monte S. Angelo, I-80126 Naples (Italy)]. E-mail: ventriglia@na.infn.it

    2005-08-08

    The quantum-classical limits for quantum tomograms are studied and compared with the corresponding classical tomograms, using two different definitions for the limit. One is the Planck limit where -bar ->0 in all -bar -dependent physical observables, and the other is the Ehrenfest limit where -bar ->0 while keeping constant the mean value of the energy. The Ehrenfest limit of eigenstate tomograms for a particle in a box and a harmonic oscillator is shown to agree with the corresponding classical tomograms of phase-space distributions, after a time averaging. The Planck limit of superposition state tomograms of the harmonic oscillator demonstrates the decreasing contribution of interference terms as -bar ->0.

  9. Tomograms in the quantum-classical transition

    International Nuclear Information System (INIS)

    The quantum-classical limits for quantum tomograms are studied and compared with the corresponding classical tomograms, using two different definitions for the limit. One is the Planck limit where -bar ->0 in all -bar -dependent physical observables, and the other is the Ehrenfest limit where -bar ->0 while keeping constant the mean value of the energy. The Ehrenfest limit of eigenstate tomograms for a particle in a box and a harmonic oscillator is shown to agree with the corresponding classical tomograms of phase-space distributions, after a time averaging. The Planck limit of superposition state tomograms of the harmonic oscillator demonstrates the decreasing contribution of interference terms as -bar ->0

  10. Deduction of Lorentz Transformations from Classical Thermodynamics

    Directory of Open Access Journals (Sweden)

    Angela M. Ares de Parga

    2015-01-01

    Full Text Available The Lorentz transformations are obtained by assuming that the laws of classical thermodynamics are invariant under changes of inertial reference frames. As Maxwell equations are used in order to deduce a wave equation that shows the constancy of the speed of light, by means of the laws of classical thermodynamics, the invariance of the Carnot cycle is deduced under reference frame changes. Starting with this result and the blackbody particle number density in a rest frame, the Lorentz transformations are obtained. A discussion about the universality of classical thermodynamics is given.

  11. Classical Statistical Mechanics and Landau Damping

    OpenAIRE

    Buchmuller, W; Jakovac, A.

    1997-01-01

    We study the retarded response function in scalar $\\phi^4$-theory at finite temperature. We find that in the high-temperature limit the imaginary part of the self-energy is given by the classical theory to leading order in the coupling. In particular the plasmon damping rate is a purely classical effect to leading order, as shown by Aarts and Smit. The dominant contribution to Landau damping is given by the propagation of classical fields in a heat bath of non-interacting fields.

  12. Hidden BRS invariance in classical mechanics

    International Nuclear Information System (INIS)

    We give in this paper a path integral formulation of classical mechanics. We do so by writing down the associated classical-generating functional. This functional exhibits an unexpected BRS-like and antiBRS-like invariance. This invariance allows for a simple expression, in term of superfields, of this generating functional. Associated to the BRS and antiBRS charges there is also a ghost charge whose conservation turns out to be nothing else than the well-known theorem of classical mechanics. (orig.)

  13. Classical-field theory of thermal radiation

    CERN Document Server

    Rashkovskiy, Sergey A

    2016-01-01

    In this paper, using the viewpoint that quantum mechanics can be constructed as a classical field theory without any quantization I build a fully classical theory of thermal radiation. Planck's law for the spectral energy density of thermal radiation and the Einstein A-coefficient for spontaneous emission are derived in the framework of classical field theory without using the concept of "photon". It is shown that the spectral energy density of thermal radiation is apparently not a universal function of frequency, as follows from the Planck's law, but depends weakly on the nature of atoms, while Planck's law is valid only as an approximation in the limit of weak excitation of atoms.

  14. Fluctuations of wavefunctions about their classical average

    International Nuclear Information System (INIS)

    Quantum-classical correspondence for the average shape of eigenfunctions and the local spectral density of states are well-known facts. In this paper, the fluctuations of the quantum wavefunctions around the classical value are discussed. A simple random matrix model leads to a Gaussian distribution of the amplitudes whose width is determined by the classical shape of the eigenfunction. To compare this prediction with numerical calculations in chaotic models of coupled quartic oscillators, we develop a rescaling method for the components. The expectations are broadly confirmed, but deviations due to scars are observed. This effect is much reduced when both Hamiltonians have chaotic dynamics

  15. Failure of classical elasticity in auxetic foams

    Directory of Open Access Journals (Sweden)

    J. H. Roh

    2013-04-01

    Full Text Available Poisson's ratio, ν, was measured for four materials, a rubbery polymer, a conventional soft foam, and two auxetic foams. We find that for the first two materials, having ν ≥ 0.2, the experimental determinations of Poisson's ratio are in good agreement with values calculated from the shear and tensile moduli using the equations of classical elasticity. However, for the two auxetic materials (ν < 0, the equations of classical elasticity give values significantly different from the measured ν. We offer an interpretation of these results based on a recently published analysis of the bounds on Poisson's ratio for classical elasticity to be applicable.

  16. Higher Dimensional Classical W-Algebras

    CERN Document Server

    Martínez-Moras, F; Martinez-Moras, Fernando; Ramos, Eduardo

    1993-01-01

    Classical $W$-algebras in higher dimensions are constructed. This is achieved by generalizing the classical Gel'fand-Dickey brackets to the commutative limit of the ring of classical pseudodifferential operators in arbitrary dimension. These $W$-algebras are the Poisson structures associated with a higher dimensional version of the Khokhlov-Zabolotskaya hierarchy (dispersionless KP-hierarchy). The two dimensional case is worked out explicitly and it is shown that the role of Diff$S(1)$ is taken by the algebra of generators of local diffeomorphisms in two dimensions.

  17. Applying classical geometry intuition to quantum spin

    Science.gov (United States)

    Durfee, Dallin S.; Archibald, James L.

    2016-09-01

    Using concepts of geometric orthogonality and linear independence, we logically deduce the form of the Pauli spin matrices and the relationships between the three spatially orthogonal basis sets of the spin-1/2 system. Rather than a mathematically rigorous derivation, the relationships are found by forcing expectation values of the different basis states to have the properties we expect of a classical, geometric coordinate system. The process highlights the correspondence of quantum angular momentum with classical notions of geometric orthogonality, even for the inherently non-classical spin-1/2 system. In the process, differences in and connections between geometrical space and Hilbert space are illustrated.

  18. Bohmian measures and their classical limit

    KAUST Repository

    Markowich, Peter

    2010-09-01

    We consider a class of phase space measures, which naturally arise in the Bohmian interpretation of quantum mechanics. We study the classical limit of these so-called Bohmian measures, in dependence on the scale of oscillations and concentrations of the sequence of wave functions under consideration. The obtained results are consequently compared to those derived via semi-classical Wigner measures. To this end, we shall also give a connection to the theory of Young measures and prove several new results on Wigner measures themselves. Our analysis gives new insight on oscillation and concentration effects in the semi-classical regime. © 2010 Elsevier Inc.

  19. Common Axioms for Inferring Classical Ensemble Dynamics and Quantum Theory

    CERN Document Server

    Parwani, R R

    2005-01-01

    Within a hamiltonian framework, the same set of physically motivated axioms is used to construct both the classical ensemble Hamilton-Jacobi equation and Schrodingers equation. Crucial roles are played by the assumptions of universality and simplicity (Occam's Razor) which restrict the number and type of of arbitrary constants that appear in the hamiltonian. In this approach, non-relativistic quantum theory is seen as the unique single parameter extension of the classical ensemble dynamics. The method is contrasted with other related constructions in the literature. Possible generalisation to the relativistic case, and some consequences of relaxing the axioms, are also discussed: for example, simple extensions of the linear Schrodinger equation lead to higher-derivative nonlinear corrections that are possibly related to gravity.

  20. Quiver Theories for Moduli Spaces of Classical Group Nilpotent Orbits

    CERN Document Server

    Hanany, Amihay

    2016-01-01

    We approach the topic of Classical group nilpotent orbits from the perspective of their moduli spaces, described in terms of Hilbert series and generating functions. We review the established Higgs and Coulomb branch quiver theory constructions for A series nilpotent orbits. We present systematic constructions for BCD series nilpotent orbits on the Higgs branches of quiver theories defined by canonical partitions; this paper collects earlier work into a systematic framework, filling in gaps and providing a complete treatment. We find new Coulomb branch constructions for above minimal nilpotent orbits, including some based upon twisted affine Dynkin diagrams. We also discuss aspects of 3d mirror symmetry between these Higgs and Coulomb branch constructions and explore dualities and other relationships, such as HyperKahler quotients, between quivers. We analyse all Classical group nilpotent orbit moduli spaces up to rank 4 by giving their unrefined Hilbert series and the Highest Weight Generating functions for ...