Latimer, Colin J.
1983-01-01
Discusses some lesser known examples of atomic phenomena to illustrate to students that the old quantum theory in its simplest (Bohr) form is not an antiquity but can still make an important contribution to understanding such phenomena. Topics include hydrogenic/non-hydrogenic spectra and atoms in strong electric and magnetic fields. (Author/JN)
Bohr-Sommerfeld Theory of the Magnetic Monopole
Pankovic, Vladan
2010-01-01
In this work we consider a simple, Bohr-Sommerfeld (Old quantum atomic) theory of the magnetic monopole. We consider the system, simply called magnetic monopole "atom", consisting of the practically standing, massive magnetic monopole as the "nucleus" and electron rotating around magnetic monopole. At this system we apply quasi-classical, Bohr-Sommerfeld quantum atomic theory. Precisely, we apply firstly, by the electron rotation, Bohr-Sommerfeld momentum quantization postulate. Secondly we use equivalence between total centrifugal force acting at rotating electron and classical magnetostatic interaction between rotating electron and magnetic monopole. It yields result practically equivalent to the Dirac quantization relation between electrical and magnetic charge.
Camilleri, Kristian
2015-01-01
Niels Bohr's doctrine of the primacy of "classical concepts" is arguably his most criticized and misunderstood view. We present a new, careful historical analysis that makes clear that Bohr's doctrine was primarily an epistemological thesis, derived from his understanding of the functional role of experiment. A hitherto largely overlooked disagreement between Bohr and Heisenberg about the movability of the "cut" between measuring apparatus and observed quantum system supports the view that, for Bohr, such a cut did not originate in dynamical (ontological) considerations, but rather in functional (epistemological) considerations. As such, both the motivation and the target of Bohr's doctrine of classical concepts are of a fundamentally different nature than what is understood as the dynamical problem of the quantum-to-classical transition. Our analysis suggests that, contrary to claims often found in the literature, Bohr's doctrine is not, and cannot be, at odds with proposed solutions to the dynamical problem...
Constitution and model. The quantum theory of Bohr and imagining the atom
Hon, Giora
2014-01-01
The quantum theory of Bohr has roots in the theories of Rutherford and J. J. Thomson on the one hand, and that of Nicholson on the other. We note that Bohr neither presented the theories of Rutherford and Thomson faithfully, nor did he refer to the theory of Nicholson in its own terms. The contrasting attitudes towards these antecedent theories is telling and reveals the philosophical disposition of Bohr. We argue that Bohr intentionally avoided the concept of model as inappropriate for describing his proposed theory. Bohr had no problem in referring to the works of others as 'models', thus separating his theory from previous theories. He was interested in uncovering 'a little piece of reality'.
Bohr's Electron was Problematic for Einstein: String Theory Solved the Problem
Webb, William
2013-04-01
Neils Bohr's 1913 model of the hydrogen electron was problematic for Albert Einstein. Bohr's electron rotates with positive kinetic energies +K but has addition negative potential energies - 2K. The total net energy is thus always negative with value - K. Einstein's special relativity requires energies to be positive. There's a Bohr negative energy conflict with Einstein's positive energy requirement. The two men debated the problem. Both would have preferred a different electron model having only positive energies. Bohr and Einstein couldn't find such a model. But Murray Gell-Mann did! In the 1960's, Gell-Mann introduced his loop-shaped string-like electron. Now, analysis with string theory shows that the hydrogen electron is a loop of string-like material with a length equal to the circumference of the circular orbit it occupies. It rotates like a lariat around its centered proton. This loop-shape has no negative potential energies: only positive +K relativistic kinetic energies. Waves induced on loop-shaped electrons propagate their energy at a speed matching the tangential speed of rotation. With matching wave speed and only positive kinetic energies, this loop-shaped electron model is uniquely suited to be governed by the Einstein relativistic equation for total mass-energy. Its calculated photon emissions are all in excellent agreement with experimental data and, of course, in agreement with those -K calculations by Neils Bohr 100 years ago. Problem solved!
Pankovic, Vladan
2010-01-01
In this work we consider some consequences of the Bohr-Sommerfeld-Hansson (Old or quasi-classical) quantum theory of the Newtonian gravity, i.e. of the "gravitational atom". We prove that in this case (for gravitational central force and quantized angular momentum) centrifugal acceleration becomes formally-theoretically dependent (proportional to fourth degree) of the mass of "gravitational electron" rotating around "gravitational nucleus" for any quantum number (state). It seemingly leads toward a paradoxical breaking of the relativistic equivalence principle which contradicts to real experimental data. We demonstrate that this equivalence principle breaking does not really appear in the (quasi classical) quantum theory, but that it necessary appears only in a hypothetical extension of the quantum theory that needs a classical like interpretation of the Bohr-Sommerfeld angular momentum quantization postulate. It is, in some sense, similar to Bell-Aspect analysis that points out that a hypothetical determinis...
Energy losses of channeled ions: the BOHR theory revisited
International Nuclear Information System (INIS)
Theoretical models are presented based on the impact parameter picture for the energy losses of channeled ions. The conceptual simplicity afforded by such an approach is quite appealing. In addition, it is found that calculations based on these models provide reasonable predictions for, and agreement with, a variety of experimental data. A useful approach is provided for meeting the challenges to theory afforded by experimental measurements on channeling phenomena
AMMARI, Zied; Falconi, Marco
2016-01-01
In the mid Sixties Edward Nelson proved the existence of a consistent quantum field theory that describes the Yukawa-like interaction of a non-relativistic nucleon field with a relativistic meson field. Since then it is thought, despite the renormalization procedure involved in the construction, that the quantum dynamics should be governed in the classical limit by a Schr\\"odinger-Klein-Gordon system with Yukawa coupling. In the present paper we prove this fact in the form of a Bohr correspon...
Reading Bohr physics and philosophy
Plotnitsky, Arkady
2006-01-01
Reading Bohr: Physics and Philosophy offers a new perspective on Niels Bohr's interpretation of quantum mechanics as complementarity, and on the relationships between physics and philosophy in Bohr's work, which has had momentous significance for our understanding of quantum theory and of the nature of knowledge in general. Philosophically, the book reassesses Bohr's place in the Western philosophical tradition, from Kant and Hegel on. Physically, it reconsiders the main issues at stake in the Bohr-Einstein confrontation and in the ongoing debates concerning quantum physics. It also devotes greater attention than in most commentaries on Bohr to the key developments and transformations of his thinking concerning complementarity. Most significant among them were those that occurred, first, under the impact of Bohr's exchanges with Einstein and, second, under the impact of developments in quantum theory itself, both quantum mechanics and quantum field theory. The importance of quantum field theory for Bohr's thi...
International Nuclear Information System (INIS)
This report is organized around the contribution of A. Pais, 'Niels Bohr and the development of physics', presented at CERN on the occasion of a special colloquium in the honour of Niels Bohr. It gives a broad survey of Bohr's life, the revolution in physics created by his quantum theory and his attempts to influence the peaceful development of nuclear energy. (orig.)
Inspirations from the theories of Bohr and Mottelson: a Canadian perspective
Ward, D.; Waddington, J. C.; Svensson, C. E.
2016-03-01
The theories developed by Bohr and Mottelson have inspired much of the world-wide experimental investigation into the structure of the atomic nucleus. On the occasion of the 40th anniversary of the awarding of their Nobel prize, we reflect on some of the experimental developments made in understanding the structure of nuclei. We have chosen to focus on experiments performed in Canada, or having strong ties to Canada, and the work included here spans virtually the whole of the second half of the 20th century. The 8π Spectrometer, which figures prominently in this story, was a novel departure for funding science in Canada that involved an intimate collaboration between a Crown Corporation (Atomic Energy of Canada Ltd) and University research, and enabled many of the insights discussed here.
Bohr's way to defining complementarity
De Gregorio, Alberto
2012-01-01
We go through Bohr's talk about complementary features of quantum theory at the Volta Conference in September 1927, by collating a manuscript that Bohr wrote in Como with the unpublished stenographic report of his talk. We conclude - also with the help of some unpublished letters - that Bohr gave a very concise speech in September. The formulation of his ideas became fully developed only between the fifth Solvay Conference, in Brussels in October, and early 1928. The unpublished stenographic ...
The theory of the Bohr-Weisskopf effect in the hyperfine structure
Karpeshin, F. F.; Trzhaskovskaya, M. B.
2015-01-01
For twenty years research into the anomalies in the HF spectra was going in a wrong direction by fighting the related Bohr-Weisskopf effect. As a way out, the model-independent way is proposed of estimating the nuclear radii from the hyper-fine splitting. The way is based on analogy of HFS to internal conversion coefficients, and the Bohr-Weisskopf effect - to the anomalies in the internal conversion coefficients. This makes transparent It is shown that the parameters which can be extracted f...
Reconsidering Bohr's reply to EPR
Halvorson, H; Halvorson, Hans; Clifton, Rob
2001-01-01
Although Bohr's reply to the EPR argument is supposed to be a watershed moment in the development of his philosophy of quantum theory, it is difficult to find a clear statement of the reply's philosophical point. Moreover, some have claimed that the point is simply that Bohr is a radical positivist. In this paper, we show that such claims are unfounded. In particular, we give a mathematically rigorous reconstruction of Bohr's reply to the \\emph{original} EPR argument that clarifies its logical structure, and which shows that it does not rest on questionable philosophical assumptions. Rather, Bohr's reply is dictated by his commitment to provide "classical" and "objective" descriptions of experimental phenomena.
The theory of the Bohr-Weisskopf effect in the hyperfine structure
Karpeshin, F. F.; Trzhaskovskaya, M. B.
2015-09-01
Description of the Bohr-Wesskopf effect in the hyperfine structure of few-electron heavy ions is a challenging problem, which can be used as a test of both QED and atomic calculations. However, for twenty years the research has actually been going in a wrong direction, aimed at fighting the Bohr-Weisskopf effect through its cancellation in specific differences. Alternatively, we propose the constructive model-independent way, which enables the nuclear radii and their momenta to be retrieved from the hyper-fine splitting (HFS). The way is based on analogy of HFS to internal conversion coefficients, and the Bohr-Weisskopf effect - to the anomalies in the internal conversion coefficients. It is shown that the parameters which can be extracted from the data are the even nuclear momenta of the magnetization distribution. The radii R2 and - for the first time - R4 are obtained in this way by analysis of the experimental HFS values for the H- and Li-like ions of 209Bi. The critical prediction concerning the HFS for the 2p1/2 state is made. The present analysis shows high sensitivity of the method to the QED effects, which offers a way of precision test of QED. Experimental recommendations are given, which are aimed at retrieving data on the HFS values for a set of a few-electron configurations of each atom.
The theory of the Bohr-Weisskopf effect in the hyperfine structure
Karpeshin, F F
2015-01-01
For twenty years research into the anomalies in the HF spectra was going in a wrong direction by fighting the related Bohr-Weisskopf effect. As a way out, the model-independent way is proposed of estimating the nuclear radii from the hyper-fine splitting. The way is based on analogy of HFS to internal conversion coefficients, and the Bohr-Weisskopf effect - to the anomalies in the internal conversion coefficients. This makes transparent It is shown that the parameters which can be extracted from the data are the even nuclear moments of the magnetization distribution. The radii $R_2$ and (for the first time) $R_4$ are thus obtained by analysis of the experimental HFS for the H- and Li-like ions of $^{209}$Bi. The critical prediction of the HFS for the $2p_{1/2}$ state is discussed. The moments may be determined in this way only if the higher QED effects are properly taken into account. Therefore, this set of the parameters form a basis of a strict QED test. Experimental prospects are discussed, aimed at retrie...
Haendler, Blanca L.
1982-01-01
Discusses the importance of teaching the Bohr atom at both freshman and advanced levels. Focuses on the development of Bohr's ideas, derivation of the energies of the stationary states, and the Bohr atom in the chemistry curriculum. (SK)
基于Bohr-Sommerfeld量子理论的X射线光谱分析%Spectrum analysis of X-ray based on Bohr-Sommerfeld quantum theory
Institute of Scientific and Technical Information of China (English)
余志强; 谢泉; 肖清泉; 赵珂杰
2009-01-01
基于Bohr-Sommerfeld量子理论,研究了特征X射线的产生机理,导出了一个按原子序数来计算特征X射线波长的公式.同时对计算推导的波长值做了系统的误差分析,得到了相对误差的规律.结果表明,计算推导的波长值与实验得到的波长值非常接近,并且在实际应用中该公式也更为简便.
Thinking on the Theory of Bohr Atom Model%对玻尔原子模型理论的若干思考
Institute of Scientific and Technical Information of China (English)
兰花艳; 朱平
2013-01-01
In this paper,we use the survey techniques to get the students’difficulties of learn-ing the Bohr's theory.On this basis,the physical nature and the inner relations of Bohr atom model theory are analyzed deeply in order to solve the students’confusions in learning the theory.%通过调查的方法了解学生学习玻尔理论的困难，在此基础上，对玻尔理论的物理本质和内在联系进行了深入的分析研究，以解决学生在学习该理论时的困惑。
[Christian Bohr and the Seven Little Devils].
Gjedde, Albert
2004-01-01
The author explores novel lessons emerging from the oxygen diffusion controversy between Christian Bohr on one side and August and Marie Krogh on the other. THe controversy found its emphatic expression in August and Marie Krogh's "Seven Little Devils", a series of papers published back-to-back in the 1910 volume of Skandinavisches Archiv für Physiologie. The Devils unjustifiably sealed the fate of Christian Bohr's theory of active cellular participation in the transport of oxygen from the lungs to the pulmonary circulation. The author's renewed examination of the original papers of Bohr and the Kroghs reveals that Bohr's concept of active cellular participation in diffusion is entirely compatible with the mechanism of capillary recruitment, for the discovery of which Krogh was later awarded Nobel's Prize, years after Bohr's untimely and unexpected death in 1911.
Willden, Jeff
2001-01-01
"Bohr's Atomic Model" is a small interactive multimedia program that introduces the viewer to a simplified model of the atom. This interactive simulation lets students build an atom using an atomic construction set. The underlying design methodology for "Bohr's Atomic Model" is model-centered instruction, which means the central model of the…
Epistemological Dimensions in Niels Bohr's Conceptualization of Complementarity
Derry, Gregory
2008-03-01
Contemporary explications of quantum theory are uniformly ahistorical in their accounts of complementarity. Such accounts typically present complementarity as a physical principle that prohibits simultaneous measurements of certain dynamical quantities or behaviors, attributing this principle to Niels Bohr. This conceptualization of complementarity, however, is virtually devoid of content and is only marginally related to Bohr's actual writing on the topic. Instead, what Bohr presented was a subtle and complex epistemological argument in which complementarity is a shorthand way to refer to an inclusive framework for the logical analysis of ideas. The important point to notice, historically, is that Bohr's work involving complementarity is not intended to be an improvement or addition to a particular physical theory (quantum mechanics), which Bohr regarded as already complete. Bohr's work involving complementarity is actually an argument related to the goals, meaning, and limitations of physical theory itself, grounded in deep epistemological considerations stemming from the fundamental discontinuity of nature on a microscopic scale.
Bohr and Ehrenfest: transformations and correspondences in the early 1920s
Pérez, Enric; Valls, Blai Pié i.
2016-06-01
We analyze the collaboration between Bohr and Ehrenfest on the quantum theory in the early 1920s (1920-1923). We focus on their reflections and developments around the adiabatic principle and the correspondence principle, the two pillars of Bohr's quantum theory of 1922-23. We argue that the evolution of Bohr's ideas after 1918 brought the two principles closer, subordinating the former to the latter. The examination of the weight Bohr attributed to each principle along the years illustrates very clearly the vicissitudes of Bohr's theory before the emergence of quantum mechanics, especially with regards to its rejection/inclusion of mechanics.
Bohr's Principle of Complementarity and Beyond
Jones, R.
2004-05-01
All knowledge is of an approximate character and always will be (Russell, Human Knowledge, 1948, pg 497,507). The laws of nature are not unique (Smolin, Three Roads to Quantum Gravity, 2001, pg 195). There may be a number of different sets of equations which describe our data just as well as the present known laws do (Mitchell, Machine Learning, 1997, pg 65-66 and Cooper, Machine Learning, Vol. 9, 1992, pg 319) In the future every field of intellectual study will possess multiple theories of its domain and scientific work and engineering will be performed based on the ensemble predictions of ALL of these. In some cases the theories may be quite divergent, differing greatly one from the other. The idea can be considered an extension of Bohr's notions of complementarity, "...different experimental arrangements.. described by different physical concepts...together and only together exhaust the definable information we can obtain about the object" (Folse, The Philosophy of Niels Bohr, 1985, pg 238). This idea is not postmodernism. Witchdoctor's theories will not form a part of medical science. Objective data, not human opinion, will decide which theories we use and how we weight their predictions.
When champions meet: Rethinking the Bohr--Einstein debate
Landsman, N P
2005-01-01
Einstein's philosophy of physics (as clarified by Fine and Howard) was predicated on his Trennungsprinzip, a combination of separability and locality, without which he believed "physical thought" and "physical laws" to be impossible. Bohr's philosophy (as elucidated by Hooker, Scheibe, Folse, Howard, and others), on the other hand, was grounded in a seemingly different doctrine about the possibility of objective knowledge, namely the necessity of classical concepts. In fact, it follows from Raggio's Theorem in algebraic quantum theory that within a suitable class of physical theories Einstein's doctrine is mathematically equivalent to Bohr's, so that quantum mechanics accommodates Einstein's Trennungsprinzip if and only if it is interpreted a la Bohr through classical physics. Unfortunately, the protagonists themselves failed to discuss their differences in a constructive way, since in its early phase their debate was blurred by an undue emphasis on the uncertainty relations, whereas in its second stage it wa...
Niels Bohr and Complementarity An Introduction
Plotnitsky, Arkady
2012-01-01
This book offers a discussion of Niels Bohr’s conception of “complementarity,” arguably his greatest contribution to physics and philosophy. By tracing Bohr’s work from his 1913 atomic theory to the introduction and then refinement of the idea of complementarity, and by explicating different meanings of “complementarity” in Bohr and the relationships between it and Bohr’s other concepts, the book aims to offer a contained and accessible, and yet sufficiently comprehensive account of Bohr’s work on complementarity and its significance.
A Simple Relativistic Bohr Atom
Terzis, Andreas F.
2008-01-01
A simple concise relativistic modification of the standard Bohr model for hydrogen-like atoms with circular orbits is presented. As the derivation requires basic knowledge of classical and relativistic mechanics, it can be taught in standard courses in modern physics and introductory quantum mechanics. In addition, it can be shown in a class that…
Brunori, Maurizio
2012-01-01
Before the outbreak of World War II, Jeffries Wyman postulated that the "Bohr effect" in hemoglobin demanded the oxygen linked dissociation of the imidazole of two histidines of the polypeptide. This proposal emerged from a rigorous analysis of the acid-base titration curves of oxy- and deoxy-hemoglobin, at a time when the information on the…
"Bohr and Einstein": A Course for Nonscience Students
Schlegel, Richard
1976-01-01
A study of the concepts of relativity and quantum physics through the work of Bohr and Einstein is the basis for this upper level course for nonscience students. Along with their scientific philosophies, the political and moral theories of the scientists are studied. (CP)
Bohr's Semiclassical Model of the Black Hole Thermodynamics
Directory of Open Access Journals (Sweden)
Panković, V.
2008-06-01
Full Text Available We propose a simple procedure for evaluating the main attributes of a Schwarzschild's black hole: Bekenstein-Hawking entropy, Hawking temperature and Bekenstein's quantization of the surface area. We make use of the condition that the circumference of a great circle on the black hole horizon contains finite and whole number of the corresponding reduced Compton's wavelength. It is essentially analogous to Bohr's quantization postulate in Bohr's atomic model interpreted by de Broglie's relation. It implies the standard meaning of the black hole entropy corresponding to surface of the quantum variation of the great circles on the black hole horizon surface area. We present black hole radiation in the form conceptually analogous to Bohr's postulate on the photon emission by discrete quantum jump of the electron within the Old quantum theory. This enables us, in accordance with Heisenberg's uncertainty relation and Bohr's correspondence principle, to make a rough estimate of the time interval for black hole evaporation, which turns out very close to time interval predicted by the standard Hawking's theory. Our calculations confirm Bekenstein's semiclassical result for the energy quantization, in variance with Frasca's (2005 calculations. Finally we speculate about the possible source-energy distribution within the black hole horizon.
Energy Technology Data Exchange (ETDEWEB)
Corda, Christian [Dipartimento di Fisica e Chimica, Istituto Universitario di Ricerca Scientifica ' Santa Rita' , Centro di Scienze Naturali, Via di Galceti, 74, 59100 Prato (Italy); Institute for Theoretical Physics and Advanced Mathematics (IFM) Einstein-Galilei, Via Santa Gonda 14, 59100 Prato (Italy); International Institute for Applicable Mathematics and Information Sciences (IIAMIS), B.M. Birla Science Centre, Adarsh Nagar, Hyderabad - 500 463 (India)
2015-03-10
The idea that black holes (BHs) result in highly excited states representing both the “hydrogen atom” and the “quasi-thermal emission” in quantum gravity is today an intuitive but general conviction. In this paper it will be shown that such an intuitive picture is more than a picture. In fact, we will discuss a model of quantum BH somewhat similar to the historical semi-classical model of the structure of a hydrogen atom introduced by Bohr in 1913. The model is completely consistent with existing results in the literature, starting from the celebrated result of Bekenstein on the area quantization.
DEFF Research Database (Denmark)
Ravn, Ib
2002-01-01
Den filosofiske arv efter Niels Bohr rummer et tabu mod at prøve at forstå, hvordan den kvantefysiske virkelighed ser ud. Det er på tide vi lægger dette billedforbud bag os. Videnskabshistorikeren Mara Beller finder årsagen til Niels Bohrs succes i effektiv retorik snarere end overlegen videnskab....
DEFF Research Database (Denmark)
Gjedde, Albert
2004-01-01
The author explores novel lessons emerging from the oxygen diffusion controversy between Christian Bohr on one side and August and Marie Krogh on the other. THe controversy found its emphatic expression in August and Marie Krogh's "Seven Little Devils", a series of papers published back-to-back i......The author explores novel lessons emerging from the oxygen diffusion controversy between Christian Bohr on one side and August and Marie Krogh on the other. THe controversy found its emphatic expression in August and Marie Krogh's "Seven Little Devils", a series of papers published back......-to-back in the 1910 volume of Skandinavisches Archiv für Physiologie. The Devils unjustifiably sealed the fate of Christian Bohr's theory of active cellular participation in the transport of oxygen from the lungs to the pulmonary circulation. The author's renewed examination of the original papers of Bohr...... and the Kroghs reveals that Bohr's concept of active cellular participation in diffusion is entirely compatible with the mechanism of capillary recruitment, for the discovery of which Krogh was later awarded Nobel's Prize, years after Bohr's untimely and unexpected death in 1911. Udgivelsesdato: 2004-null...
Atoms, metaphors and paradoxes Niels Bohr and the construction of a new physics
Petruccioli, Sandro
2006-01-01
This book gives a detailed study of the development and the interpretation given to Niels Bohr's Principle of Correspondence. It also describes the role that this principle played in guiding Bohr's research over the critical period from 1920 to 1927. Quantum mechanics, developed in the 1920s and 1930s by Bohr, Heisenberg, Born, Schrödinger and Dirac, represents one of the most profound turning points in science. This theory required a wholly new kind of physics in which many of the principles, concepts and models representing reality, that had formed the basis of classical physics since Galileo and Newton, had to be abandoned. This book re-examines the birth of quantum mechanics, in particular examining the development of crucial and original insights of Niels Bohr.
Bohr vs. Einstein: Fortolkning af kvantemekanikken
DEFF Research Database (Denmark)
Andersen, Christian Kraglund; Wade, Andrew Christopher James
2013-01-01
Siden 1913, da Bohr fremlagde sin kvantemekaniske model for atomet, har fysikere diskuteret, hvordan kvan- temekanikken skal fortolkes. Specielt aktive i denne diskussion var Bohr og Einstein, som havde modstridende opfattelser af, hvordan kvantemekanikken skulle forstås. Kan katte være både...... levende og døde på samme tid? Kan vi teleportere partikler mellem Månen og Jorden? Disse spørgsmål, og mange flere, forsøgte Bohr og Einstein at besvare, og det vil vi ligeledes i denne artikel....
Niels Bohr on the wave function and the classical/quantum divide
Zinkernagel, Henrik
2016-02-01
It is well known that Niels Bohr insisted on the necessity of classical concepts in the account of quantum phenomena. But there is little consensus concerning his reasons, and what he exactly meant by this. In this paper, I re-examine Bohr's interpretation of quantum mechanics, and argue that the necessity of the classical can be seen as part of his response to the measurement problem. More generally, I attempt to clarify Bohr's view on the classical/quantum divide, arguing that the relation between the two theories is that of mutual dependence. An important element in this clarification consists in distinguishing Bohr's idea of the wave function as symbolic from both a purely epistemic and an ontological interpretation. Together with new evidence concerning Bohr's conception of the wave function collapse, this sets his interpretation apart from both standard versions of the Copenhagen interpretation, and from some of the reconstructions of his view found in the literature. I conclude with a few remarks on how Bohr's ideas make much sense also when modern developments in quantum gravity and early universe cosmology are taken into account.
Experimental Observation of Bohr's Nonlinear Fluidic Surface Oscillation.
Moon, Songky; Shin, Younghoon; Kwak, Hojeong; Yang, Juhee; Lee, Sang-Bum; Kim, Soyun; An, Kyungwon
2016-01-01
Niels Bohr in the early stage of his career developed a nonlinear theory of fluidic surface oscillation in order to study surface tension of liquids. His theory includes the nonlinear interaction between multipolar surface oscillation modes, surpassing the linear theory of Rayleigh and Lamb. It predicts a specific normalized magnitude of 0.416η(2) for an octapolar component, nonlinearly induced by a quadrupolar one with a magnitude of η much less than unity. No experimental confirmation on this prediction has been reported. Nonetheless, accurate determination of multipolar components is important as in optical fiber spinning, film blowing and recently in optofluidic microcavities for ray and wave chaos studies and photonics applications. Here, we report experimental verification of his theory. By using optical forward diffraction, we measured the cross-sectional boundary profiles at extreme positions of a surface-oscillating liquid column ejected from a deformed microscopic orifice. We obtained a coefficient of 0.42 ± 0.08 consistently under various experimental conditions. We also measured the resonance mode spectrum of a two-dimensional cavity formed by the cross-sectional segment of the liquid jet. The observed spectra agree well with wave calculations assuming a coefficient of 0.414 ± 0.011. Our measurements establish the first experimental observation of Bohr's hydrodynamic theory. PMID:26803911
Experimental Observation of Bohr's Nonlinear Fluidic Surface Oscillation.
Moon, Songky; Shin, Younghoon; Kwak, Hojeong; Yang, Juhee; Lee, Sang-Bum; Kim, Soyun; An, Kyungwon
2016-01-25
Niels Bohr in the early stage of his career developed a nonlinear theory of fluidic surface oscillation in order to study surface tension of liquids. His theory includes the nonlinear interaction between multipolar surface oscillation modes, surpassing the linear theory of Rayleigh and Lamb. It predicts a specific normalized magnitude of 0.416η(2) for an octapolar component, nonlinearly induced by a quadrupolar one with a magnitude of η much less than unity. No experimental confirmation on this prediction has been reported. Nonetheless, accurate determination of multipolar components is important as in optical fiber spinning, film blowing and recently in optofluidic microcavities for ray and wave chaos studies and photonics applications. Here, we report experimental verification of his theory. By using optical forward diffraction, we measured the cross-sectional boundary profiles at extreme positions of a surface-oscillating liquid column ejected from a deformed microscopic orifice. We obtained a coefficient of 0.42 ± 0.08 consistently under various experimental conditions. We also measured the resonance mode spectrum of a two-dimensional cavity formed by the cross-sectional segment of the liquid jet. The observed spectra agree well with wave calculations assuming a coefficient of 0.414 ± 0.011. Our measurements establish the first experimental observation of Bohr's hydrodynamic theory.
Applications of Bohr's correspondence principle
Crawford, Frank S.
1989-07-01
The Bohr correspondence-principle (cp) formula dE/dn=ℏω is presented (ω is the classical angular frequency) and its predicted energy levels En are compared to those given by the stationary state solutions of the Schrödinger equation, first for several examples in one dimension (1D), including the ``quantum bouncer,'' and then for several examples in three dimensions (3D), including the hydrogen atom and the isotropic harmonic oscillator. For the 3-D cases, the cp predictions based on classical circular orbits are compared with the ``circlelike'' Schrödinger solutions (those with the lowest energy eigenvalue for a given l) and the cp predictions based on classical ``needle'' orbits (having zero angular momentum) with the Schrödinger l=0 solutions. For the H atom and the isotropic oscillator, the cp prediction does not depend on the classical orbit chosen because of a ``degeneracy'': the fact that for these systems ω is independent of the orbit. As a more stringent test of the cp, analogous nondegenerate systems V=-k/r3/2 in place of the H-atom potential V=-e2/r and V=kr4 in place of the oscillator potential V=(1/2)mω2r2 are therefore considered. An interesting anomaly that occurs for the harmonic oscillator and its nondegenerate analog V=kr4 is encountered (but not for the H atom nor its nondegenerate analog V=-k/r3/2), wherein half of the states predicted by application of the cp to the needle orbits are ``spurious'' in that there are no corresponding Schrödinger l=0 states. The assumption that generated the spurious cp states is uncovered—a plausible, but erroneous factor of 2 in calculating the classical frequency—and thus the spurious states are eliminated.
Love, literature and the quantum atom Niels Bohr's 1913 trilogy revisited
Aaserud, Finn
2013-01-01
Niels Bohr ranks with Einstein among the physicists of the 20th century. He rose to this status through his invention of the quantum theory of the atom and his leadership in its defense and development. He also ranks with Einstein in his humanism and his sense of responsibility to his science and the society that enabled him to create it. Our book presents unpublished excerpts from extensive correspondence between Bohr and his immediate family, and uses it to describe and analyze the psychological and cultural background to his invention. The book also contains a reprinting of the three papers of 1913 - the "Trilogy" - in which Bohr worked out the provisional basis of a quantum theory of the atom.
Challenges to Bohr's Wave-Particle Complementarity Principle
Rabinowitz, Mario
2013-02-01
Contrary to Bohr's complementarity principle, in 1995 Rabinowitz proposed that by using entangled particles from the source it would be possible to determine which slit a particle goes through while still preserving the interference pattern in the Young's two slit experiment. In 2000, Kim et al. used spontaneous parametric down conversion to prepare entangled photons as their source, and almost achieved this. In 2012, Menzel et al. experimentally succeeded in doing this. When the source emits entangled particle pairs, the traversed slit is inferred from measurement of the entangled particle's location by using triangulation. The violation of complementarity breaches the prevailing probabilistic interpretation of quantum mechanics, and benefits Bohm's pilot-wave theory.
DEFF Research Database (Denmark)
Rüdiger, Mogens
2005-01-01
Anmeldelse af David Favrholdt: Spaltningen. Niels Bohr og Werner Heisenberg i videnskab og politik.......Anmeldelse af David Favrholdt: Spaltningen. Niels Bohr og Werner Heisenberg i videnskab og politik....
Niels Bohr on the wave function and the classical/quantum divide
Zinkernagel, Henrik
2016-01-01
It is well known that Niels Bohr insisted on the necessity of classical concepts in the account of quantum phenomena. But there is little consensus concerning his reasons, and what he exactly meant by this. In this paper, I re-examine Bohr's interpretation of quantum mechanics, and argue that the necessity of the classical can be seen as part of his response to the measurement problem. More generally, I attempt to clarify Bohr's view on the classical/quantum divide, arguing that the relation between the two theories is that of mutual dependence. An important element in this clarification consists in distinguishing Bohr's idea of the wave function as symbolic from both a purely epistemic and an ontological interpretation. Together with new evidence concerning Bohr's conception of the wave function collapse, this sets his interpretation apart from both standard versions of the Copenhagen interpretation, and from some of the reconstructions of his view found in the literature. I conclude with a few remarks on ho...
Relation between energy and mass in Bohr's essay on his debate with Einstein
International Nuclear Information System (INIS)
The famous debate between Einstein and Bohr on the (in)consistency of quantum mechanics was described in detail by Bohr in his essay of 1949. The present article comments not on the main subject of the debate but only on the terminology that is relevant to the notions of the theory of relativity and which was used by the participants. In particular, their statement on the equivalence of mass and energy should not be taken literally. In fact, the rest energy is meant here. The authority of the two great physicists should not be misused to preserve the confusing terminology
What classicality? Decoherence and Bohr's classical concepts
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...
Bohr Hamiltonian with time-dependent potential
Naderi, L.; Hassanabadi, H.; Sobhani, H.
2016-04-01
In this paper, Bohr Hamiltonian has been studied with the time-dependent potential. Using the Lewis-Riesenfeld dynamical invariant method appropriate dynamical invariant for this Hamiltonian has been constructed and the exact time-dependent wave functions of such a system have been derived due to this dynamical invariant.
EPR before EPR: A 1930 Einstein-Bohr thought Experiment Revisited
Nikolic, Hrvoje
2012-01-01
In 1930, Einstein argued against the consistency of the time-energy uncertainty relation by discussing a thought experiment involving a measurement of the mass of the box which emitted a photon. Bohr seemingly prevailed over Einstein by arguing that Einstein's own general theory of relativity saves the consistency of quantum mechanics. We revisit…
DEFF Research Database (Denmark)
Gjedde, Albert
2010-01-01
The year 2010 is the centennial of the publication of the “Seven Little Devils” in the predecessor of Acta Physiologica. In these seven papers, August and Marie Krogh sought to refute Christian Bohr's theory that oxygen diffusion from the lungs to the circulation is not entirely passive but rather...... facilitated by a specific cellular activity substitute to secretion. The subjects of the present reevaluation of this controversy are Christian Bohr, Professor and Doctor of Medicine (1855–1911), nominated three times for the Nobel Prize; August Krogh, Doctor of Philosophy (1874–1949), Christian Bohr...... and posterity recognized. Posterity has judged the dispute unilaterally from the Nobel laureate's point of view, but it is evident that August Krogh's Nobel Prize was awarded for the discovery of a cellular activity (Christian Bohr's expression), represented by Krogh's discovery of capillary recruitment...
Analytical Special Solutions of the Bohr Hamiltonian
Bonatsos, D; Petrellis, D; Terziev, P A; Yigitoglu, I
2005-01-01
The following special solutions of the Bohr Hamiltonian are briefly described: 1) Z(5) (approximately separable solution in five dimensions with gamma close to 30 degrees), 2) Z(4) (exactly separable gamma-rigid solution in four dimensions with gamma = 30 degrees), 3) X(3) (exactly separable gamma-rigid solution in three dimensions with gamma =0). The analytical solutions obtained using Davidson potentials in the E(5), X(5), Z(5), and Z(4) frameworks are also mentioned.
Ralston, J P
2003-01-01
Recently Buniy and Kephart made an astonishing empirical observation, which anyone can reproduce at home. Measure the {\\it lengths} of closed knots tied from ordinary rope. The ``double do-nut'', and the beautiful trefoil knot are examples. Tie the knots tightly, and glue or splice the tails into a seamless unity. Compare two knots with corresponding members of the mysterious particle states known as ``glueball'' candidates in the literature. Propose that the microscopic glueball mass ought to be proportional to the macroscopic mass of the corresponding knot. Fit two parameters, then {\\it predict} 12 of 12 remaining glueball masses with extraordinary accuracy, knot by knot. Here we relate these observations to the fundamental gauge theory of gluons, by recognizing a hidden gauge symmetry bent into the knots. As a result the existence and importance of a gluon mass parameter is clarified. Paradoxically forbidden by the usual framework, the gluon mass cannot be expressed in the usual coordinates, but has a natu...
Address at the opening session of the Niels Bohr Symposium
International Nuclear Information System (INIS)
In his address at the opening session of the Niels Bohr Symposium organized jointly by UNESCO and the Niels Bohr Institute in Copenhagen in May 1998 in order to examine the latest developments in key fields of physics, the Director General of UNESCO presented the scientific work and the spirit of Niels Bohr, emphasizing the impact of his discoveries for new openings in science and in society in general
Challenges to the Bohr Wave Particle Complementarity Principle
Rabinowitz, Mario
2012-01-01
Contrary to the Bohr complementarity principle, in 1995 Rabinowitz proposed that by using entangled particles from the source it would be possible to determine which slit a particle goes through while still preserving the interference pattern in the Young two slit experiment. In 2000, Kim et al used spontaneous parametric down conversion to prepare entangled photons as their source, and almost achieved this. In 2012, Menzel et al. experimentally succeeded in doing this. When the source emits entangled particle pairs, the traversed slit is inferred from measurement of the entangled particle location by using triangulation. The violation of complementarity breaches the prevailing probabilistic interpretation of quantum mechanics, and benefits the Bohm pilot wave theory.
Bohr-Sommerfeld Quantization of Space
Bianchi, Eugenio
2012-01-01
We introduce semiclassical methods into the study of the volume spectrum in loop gravity. The classical system behind a 4-valent spinnetwork node is a Euclidean tetrahedron. We investigate the tetrahedral volume dynamics on phase space and apply Bohr-Sommerfeld quantization to find the volume spectrum. The analysis shows a remarkable quantitative agreement with the volume spectrum computed in loop gravity. Moreover, it provides new geometrical insights into the degeneracy of this spectrum and the maximum and minimum eigenvalues of the volume on intertwiner space.
Bohr Inequality for Multiple Op erators
Institute of Scientific and Technical Information of China (English)
LIAN Tie-yan; TANG Wei
2016-01-01
An absolute value equation is established for linear combinations of two operators. When the parameters take special values, the parallelogram law of operator type is given. In addition, the operator equation in literature [3] and its equivalent deformation are obtained. Based on the equivalent deformation of the operator equation and using the properties of conjugate number as well as the operator, an absolute value identity of multiple operators is given by means of mathematical induction. As Corollaries, Bohr inequalities are extended to multiple operators and some related inequalities are reduced to, such as inequalities in [2] and [3].
Discreteness of the volume of space from Bohr-Sommerfeld quantization
Bianchi, Eugenio
2011-01-01
A major challenge for any theory of quantum gravity is to quantize general relativity while retaining some part of its geometrical character. We present new evidence for the idea that this can be achieved by directly quantizing space itself. We compute the Bohr-Sommerfeld volume spectrum of a tetrahedron and show that it reproduces the quantization of a grain of space found in loop gravity.
Bohr effect of hemoglobins: Accounting for differences in magnitude.
Okonjo, Kehinde O
2015-09-01
The basis of the difference in the Bohr effect of various hemoglobins has remained enigmatic for decades. Fourteen amino acid residues, identical in pairs and located at specific 'Bohr group positions' in human hemoglobin, are implicated in the Bohr effect. All 14 are present in mouse, 11 in dog, eight in pigeon and 13 in guinea pig hemoglobin. The Bohr data for human and mouse hemoglobin are identical: the 14 Bohr groups appear at identical positions in both molecules. The dog data are different from the human because three Bohr group positions are occupied by non-ionizable groups in dog hemoglobin; the pigeon data are vastly different from the human because six Bohr group positions are occupied by non-ionizable groups in pigeon hemoglobin. The guinea pig data are quite complex. Quantitative analyses showed that only the pigeon data could be fitted with the Wyman equation for the Bohr effect. We demonstrate that, apart from guinea pig hemoglobin, the difference between the Bohr effect of each of the other hemoglobins and of pigeon hemoglobin can be accounted for quantitatively on the basis of the occupation of some of their Bohr group positions by non-ionizable groups in pigeon hemoglobin. We attribute the anomalous guinea pig result to a new salt-bridge formed in its R2 quaternary structure between the terminal NH3(+) group of one β-chain and the COO(-) terminal group of the partner β-chain in the same molecule. The pKas of this NH3(+) group are 6.33 in the R2 and 4.59 in the T state.
The solution of the Bohr Hamiltonian with Hulthen potential%用Hulthen势解Bohr Hamiltonian
Institute of Scientific and Technical Information of China (English)
张伦东; 方向正; 郭建友
2009-01-01
在解Bohr Hamihonian的过程中出现了很多种方法,且有很多在最后都是用不同的势来得到不同的解析解,典型的有Coulomb-like和Kratzer-like势、Linear势、Davidson势.除此之外,还有Bohr's Harmonic-Oscillator解法、Wilets and Jean解法、Elliott-Evans-Park's解法等.这些解法都给出了与实验室比较接近的光谱,但其中有一个普遍现象:很多最后的解析能谱都比实验能谱低.在该文中用Hulthen势来作出它的修正能谱,以更好地与实验值接近.最后,用240U和240Pu作为例子来进行比较.
How Sommerfeld extended Bohr's model of the atom (1913-1916)
Eckert, Michael
2014-04-01
Sommerfeld's extension of Bohr's atomic model was motivated by the quest for a theory of the Zeeman and Stark effects. The crucial idea was that a spectral line is made up of coinciding frequencies which are decomposed in an applied field. In October 1914 Johannes Stark had published the results of his experimental investigation on the splitting of spectral lines in hydrogen (Balmer lines) in electric fields, which showed that the frequency of each Balmer line becomes decomposed into a multiplet of frequencies. The number of lines in such a decomposition grows with the index of the line in the Balmer series. Sommerfeld concluded from this observation that the quantization in Bohr's model had to be altered in order to allow for such decompositions. He outlined this idea in a lecture in winter 1914/15, but did not publish it. The First World War further delayed its elaboration. When Bohr published new results in autumn 1915, Sommerfeld finally developed his theory in a provisional form in two memoirs which he presented in December 1915 and January 1916 to the Bavarian Academy of Science. In July 1916 he published the refined version in the Annalen der Physik. The focus here is on the preliminary Academy memoirs whose rudimentary form is better suited for a historical approach to Sommerfeld's atomic theory than the finished Annalen-paper. This introductory essay reconstructs the historical context (mainly based on Sommerfeld's correspondence). It will become clear that the extension of Bohr's model did not emerge in a singular stroke of genius but resulted from an evolving process.
Gjedde, Albert
2010-01-01
The year 2010 is the centennial of the publication of the "Seven Little Devils" in the predecessor of "Acta Physiologica". In these seven papers, August and Marie Krogh sought to refute Christian Bohr's theory that oxygen diffusion from the lungs to the circulation is not entirely passive but rather facilitated by a specific cellular activity…
Solutions of the Bohr hamiltonian, a compendium
Fortunato, L
2004-01-01
The Bohr hamiltonian, also called collective hamiltonian, is one of the cornerstone of nuclear physics and a wealth of solutions (analytic or approximated) of the associated eigenvalue equation have been proposed over more than half a century (confining ourselves to the quadrupole degree of freedom). Each particular solution is associated with a peculiar form for the $V(\\beta,\\gamma)$ potential. The large number and the different details of the mathematical derivation of these solutions, as well as their increased and renewed importance for nuclear structure and spectroscopy, demand a thorough discussion. It is the aim of the present monograph to present in detail all the known solutions in $\\gamma-$unstable and $\\gamma-$stable cases, in a taxonomic and didactical way. In pursuing this task we especially stressed the mathematical side leaving the discussion of the physics to already published comprehensive material. The paper contains also a new approximate solution for the linear potential, and a new solutio...
Darwinism in disguise? A comparison between Bohr's view on quantum mechanics and QBism.
Faye, Jan
2016-05-28
The Copenhagen interpretation is first and foremost associated with Niels Bohr's philosophy of quantum mechanics. In this paper, I attempt to lay out what I see as Bohr's pragmatic approach to science in general and to quantum physics in particular. A part of this approach is his claim that the classical concepts are indispensable for our understanding of all physical phenomena, and it seems as if the claim is grounded in his reflection upon how the evolution of language is adapted to experience. Another, recent interpretation, QBism, has also found support in Darwin's theory. It may therefore not be surprising that sometimes QBism is said to be of the same breed as the Copenhagen interpretation. By comparing the two interpretations, I conclude, nevertheless, that there are important differences.
A Bohr-type model with gravity as the attractive force
Vayenas, C G; Fokas, A
2013-01-01
We formulate a Bohr-type rotating particle model for three light particles of the same rest mass, forming a bound rotational state under the influence of their gravitational attraction, in the same way that electrostatic attraction leads to the formation of a bound proton-electron state in the classical Bohr model of the H atom. By using special relativity, the equivalence principle and the de Broglie wavelength equation, we find that when the three rotating particles have the rest masses of neutrinos or antineutrinos then surprisingly the rest mass of the rotating state has the rest mass of the stable baryons, i.e. of the proton and the neutron. This rest mass is due almost exclusively to the kinetic energy of the rotating neutrinos. The results are found to be consistent with the theory of general relativity. Predictions for the properties of these bound rotational states are compared with experimental values.
Matsuyanagi, Kenichi; Matsuo, Masayuki; Nakatsukasa, Takashi; Yoshida, Kenichi; Hinohara, Nobuo; Sato, Koichi
2016-06-01
We discuss the nature of the low-frequency quadrupole vibrations from small-amplitude to large-amplitude regimes. We consider full five-dimensional quadrupole dynamics including three-dimensional rotations restoring the broken symmetries as well as axially symmetric and asymmetric shape fluctuations. Assuming that the time evolution of the self-consistent mean field is determined by five pairs of collective coordinates and collective momenta, we microscopically derive the collective Hamiltonian of Bohr and Mottelson, which describes low-frequency quadrupole dynamics. We show that the five-dimensional collective Schrödinger equation is capable of describing large-amplitude quadrupole shape dynamics seen as shape coexistence/mixing phenomena. We summarize the modern concepts of microscopic theory of large-amplitude collective motion, which is underlying the microscopic derivation of the Bohr-Mottelson collective Hamiltonian.
Matsuyanagi, Kenichi; Nakatsukasa, Takashi; Yoshida, Kenichi; Hinohara, Nobuo; Sato, Koichi
2016-01-01
We discuss the nature of the low-frequency quadrupole vibrations from small-amplitude to large-amplitude regimes. We consider full five-dimensional quadrupole dynamics including three-dimensional rotations restoring the broken symmetries as well as axially symmetric and asymmetric shape fluctuations. Assuming that the time-evolution of the self-consistent mean field is determined by five pairs of collective coordinates and collective momenta, we microscopically derive the collective Hamiltonian of Bohr and Mottelson, which describes low-frequency quadrupole dynamics. We show that the five-dimensional collective Schr\\"odinger equation is capable of describing large-amplitude quadrupole shape dynamics seen as shape coexistence/mixing phenomena. We summarize the modern concepts of microscopic theory of large-amplitude collective motion, which is underlying the microscopic derivation of the Bohr-Mottelson collective Hamiltonian.
Relativistic Corrections to the Bohr Model of the Atom
Kraft, David W.
1974-01-01
Presents a simple means for extending the Bohr model to include relativistic corrections using a derivation similar to that for the non-relativistic case, except that the relativistic expressions for mass and kinetic energy are employed. (Author/GS)
Loring, FH
2014-01-01
Summarising the most novel facts and theories which were coming into prominence at the time, particularly those which had not yet been incorporated into standard textbooks, this important work was first published in 1921. The subjects treated cover a wide range of research that was being conducted into the atom, and include Quantum Theory, the Bohr Theory, the Sommerfield extension of Bohr's work, the Octet Theory and Isotopes, as well as Ionisation Potentials and Solar Phenomena. Because much of the material of Atomic Theories lies on the boundary between experimentally verified fact and spec
Hemoglobin Bohr effects: atomic origin of the histidine residue contributions.
Zheng, Guishan; Schaefer, Michael; Karplus, Martin
2013-11-26
The Bohr effect in hemoglobin, which refers to the dependence of the oxygen affinity on the pH, plays an important role in its cooperativity and physiological function. The dominant contribution to the Bohr effect arises from the difference in the pKa values of His residues of the unliganded (deoxy) and liganded (carbonmonoxy) structures. Using recent high resolution structures, the residue pKa values corresponding to the two structures are calculated. The method is based on determining the electrostatic interactions between residues in the protein, relative to those of the residue in solution, by use of the linearized finite difference Poisson-Boltzmann equation and Monte Carlo sampling of protonation states. Given that good agreement is obtained with the available experimental values for the contribution of His residues in HbA to the Bohr effect, the calculated results are used to determine the atomic origin of the pKa shift between deoxy and carbonmonoxy HbA. The contributions to the pKa shift calculated by means of the linear response approximation show that the salt bridge involving His146 plays an important role in the alkaline Bohr effect, as suggested by Perutz but that other interactions are significant as well. A corresponding analysis is made for the contribution of His143 to the acid Bohr effect for which there is no proposed explanation. The method used is summarized and the program by which it is implemented is described in the Appendix .
The Bohr-Heisenberg correspondence principle viewed from phase space
DEFF Research Database (Denmark)
Dahl, Jens Peder
2002-01-01
Phase-space representations play an increasingly important role in several branches of physics. Here, we review the author's studies of the Bohr-Heisenberg correspondence principle within the Weyl-Wigner phase-space representation. The analysis leads to refined correspondence rules that can...
Complementarity in the Einstein-Bohr photon box
Dieks, D.G.B.J.; Lam, S
2008-01-01
The Bohr-Einstein photon box thought experiment is a forerunner of the EPR experiment: a packet of radiation escapes from a box, and the box-plus-radiation state remains entangled. Hence, a measurement on the box makes a difference for the state of the far-away radiation long after its escape. This
Bohr's Relational Holism and the classical-quantum Interaction
Dorato, Mauro
2016-01-01
In this paper I present and critically discuss the main strategies that Bohr used and could have used to fend off the charge that his interpretation does not provide a clear-cut distinction between the classical and the quantum domain. In particular, in the first part of the paper I reassess the main arguments used by Bohr to advocate the indispensability of a classical framework to refer to quantum phenomena. In this respect, by using a distinction coming from an apparently unrelated philosophical corner, we could say that Bohr is not a revisionist philosopher of physics but rather a descriptivist one in the sense of Strawson. I will then go on discussing the nature of the holistic link between classical measurement apparatuses and observed system that he also advocated. The oft-repeated conclusion that Bohr's interpretation of the quantum formalism is untenable can only be established by giving his arguments as much force as possible, which is what I will try to do in the following by remaining as faithful ...
O centenário da molécula de Bohr
Directory of Open Access Journals (Sweden)
Carlos A. L. Filgueiras
2013-01-01
Full Text Available A hundred years ago, a twenty-eight year old Danish scientist published a series of three papers in which electron motion was quantized. The Bohr atomic model is surely known by every chemistry student. Nevertheless in this same 1913 trilogy, Bohr studied atoms with several electrons as well as molecules. Chemistry students, in general, are not aware of the Bohr molecule. The present paper aims at rescuing this important classical model. A review of the Bohr atomic model for both one and several electrons is discussed, together with a theoretical presentation of the Bohr molecule.
The Niels Bohr Archive is Placing Collections on its Website
DEFF Research Database (Denmark)
Aaserud, Finn
2010-01-01
our small staff was also occupied with other matters, such as completing the Niels Bohr Collected Works. In early 2007 my old friend Joe Anderson at the AIP Center for History of Physics alerted us to the existence of the archives software Archon, freely available from the University of Illinois....... However, it took another year and a half just to be able to install the software, a process which proved to require extensive assistance from the infrastructure of our host institution, the Niels Bohr Institute (NBI). Nor was learning how to find one’s way around in the software, once installed, a trivial...... of our already existing catalogues was imported into Archon. As a consequence, a user can now easily search and move around in and across catalogues. Fortunately, Archon allows linkage to digital documents outside the software itself, and we were thus able to link from the document level...
Bohr--Sommerfeld Lagrangians of moduli spaces of Higgs bundles
DEFF Research Database (Denmark)
Biswas, Indranil; Gammelgaard, Niels Leth; Logares, Marina
Let $X$ be a compact connected Riemann surface of genus at least two. Let $M_H(r,d)$ denote the moduli space of semistable Higgs bundles on $X$ of rank $r$ and degree $d$. We prove that the compact complex Bohr-Sommerfeld Lagrangians of $M_H(r,d)$ are precisely the irreducible components of the n...... of the nilpotent cone in $M_H(r,d)$. This generalizes to Higgs $G$-bundles and also to the parabolic Higgs bundles....
Experimental Test of Bohr's Complementarity Principle with Single Neutral Atom
WANG, Zhihui; TIAN, YALI; Yang, Chen; Zhang, Pengfei; Li, Gang; Zhang, Tiancai
2016-01-01
Bohr's complementarity principle (BCP) is one of the cornerstones of quantum mechanics, and the counterintuitive behavior of wave-particle duality lies at its heart.BCP says that the properties of waves and particles for a quantum system cannot be simultaneously observed. Various tests of BCP with single photons have been performed.However, the low detection efficiency associated with fast-moving, massless photons makes the results less persuasive and more untenable. Here we use a well-contro...
QBism, Bohr, and the quantum omelette tossed by de Ronde
Mohrhoff, Ulrich
2016-01-01
In his recent paper "QBism, FAPP and the Quantum Omelette" [1608.00548v1] de Ronde makes a variety of questionable claims concerning QBism, Bohr, and the present author's critical appraisal of QBism [1409.3312v1]. These claims are examined. Subsequently an outline is presented of what one might see if one looks into the quantum domain through the window provided by the quantum-mechanical correlations between outcome-indicating events in the classical domain.
De novo nonsense mutations in ASXL1 cause Bohring-Opitz syndrome
DEFF Research Database (Denmark)
Hoischen, Alexander; van Bon, Bregje W M; Rodríguez-Santiago, Benjamín;
2011-01-01
Bohring-Opitz syndrome is characterized by severe intellectual disability, distinctive facial features and multiple congenital malformations. We sequenced the exomes of three individuals with Bohring-Opitz syndrome and in each identified heterozygous de novo nonsense mutations in ASXL1, which...... is required for maintenance of both activation and silencing of Hox genes. In total, 7 out of 13 subjects with a Bohring-Opitz phenotype had de novo ASXL1 mutations, suggesting that the syndrome is genetically heterogeneous....
The Compton Radius, the de Broglie Radius, the Planck Constant, and the Bohr Orbits
Directory of Open Access Journals (Sweden)
Daywitt W. C.
2011-04-01
Full Text Available The Bohr orbits of the hydrogen atom and the Planck constant can be derived classically from the Maxwell equations and the assumption that there is a variation in the electron's velocity about its average value. The resonant nature of the circulating electron and its induced magnetic and Faraday fields prevents a radiative collapse of the electron into the nuclear proton. The derived Planck constant is $h=2pi e^2/alpha c$, where $e$, $alpha$, and $c$ are the electronic charge, the fine structure constant, and the speed of light. The fact that the Planck vacuum (PV theory derives the same Planck constant independently of the above implies that the two derivations are related. The following highlights that connection.
The Compton Radius, the de Broglie Radius, the Planck Constant, and the Bohr Orbits
Directory of Open Access Journals (Sweden)
Daywitt W. C.
2011-04-01
Full Text Available The Bohr orbits of the hydrogen atom and the Planck constant can be derived classically from the Maxwell equations and the assumption that there is a variation in the electron’s velocity about its average value [1]. The resonant nature of the circulating electron and its induced magnetic and Faraday fields prevents a radiative collapse of the electron into the nuclear proton. The derived Planck constant is h = 2 e 2 = c , where e , , and c are the electronic charge, the fine structure constant, and the speed of light. The fact that the Planck vacuum (PV theory [2] derives the same Planck constant independently of the above implies that the two derivations are related. The following highlights that connection.
Bohr-Weisskopf effect. Experiment with an ion trap
International Nuclear Information System (INIS)
Recent developments of ion-trap and laser-microwave spectroscopy techniques enable us to measure the ground-state hyperfine structure with very high accuracy. The magnetic hyperfine coupling constant A shows a small but finite isotope dependence called hyperfine anomaly, the main part of which stems from the finite size of the magnetization distribution in the nucleus (Bohr-Weisskopf effect). This effect affords unique and interesting probe for the valence neutron distribution in a nucleus, particularly in a so called halo nucleus. (author)
Traffic restrictions on Routes Bloch, Maxwell and Bohr
IT Department
2008-01-01
Excavation and pipework is being carried out in the framework of the transfer of the waste water treatment plant for the effluents from the surface treatment workshops from Building 254 to Building 676, currently under construction. This work may encroach onto Routes Bloch, Maxwell and Bohr and disrupt the flow of traffic. Users are requested to comply with the road signs that will be erected. The work is expected to last until the beginning of December 2008. Thank you for your understanding. TS/CE and TS/FM Groups Tel.7 4188 or 16 4314
Bohr Hamiltonian with Eckart potential for triaxial nuclei
Naderi, L.; Hassanabadi, H.
2016-05-01
In this paper, the Bohr Hamiltonian has been solved using the Eckart potential for the β-part and a harmonic oscillator for the γ-part of the Hamiltonian. The approximate separation of the variables has been possible by choosing the convenient form for the potential V(β,γ). Using the Nikiforov-Uvarov method the eigenvalues and eigenfunctions of the eigenequation for the β-part have been derived. An expression for the total energy of the levels has been represented.
El modelo semicuántico de Bohr en los libros de texto The Bohr's quantum model in the textbook
Directory of Open Access Journals (Sweden)
Jorge Eliécer Moreno Ramírez
2010-01-01
Full Text Available La didáctica de las ciencias naturales está cuestionando la transposición de los modelos científicos en modelos didácticos. Otras investigaciones muestran que el conocimiento científico convertido en conocimiento escolar produce deformaciones de la actividad científica y la simplificación de modelos, contribuyendo con la actitud negativa de los estudiantes hacia las ciencias y al fracaso escolar reportado por algunos estudios. Se pregunta si el modelo atómico de Bohr que se muestra en los textos se corresponde histórica y epistemológicamente con las actividades científicas y cuáles son las posibles deformaciones que de ésta se hace cuando se muestra el modelo en los libros. Los resultados de la investigación muestran una clara diferencia entre la propuesta de Bohr (1913 y la transposición del modelo, lo que invita a una reflexión profunda acerca de la confiabilidad que pueden tener los textos utilizados para la enseñanza de la ciencia químicaNatural science teaching is questioning the transposition that is made of scientific models into didactic models, because research has shown that when scientific knowledge is transformed into scholarly knowledge in order to be taught it causes the deformation of the scientific activity and the simplification of the models. This contributes to the negative attitude of students towards science, and student failure shown in some studies. This research inquired if the transposition of Bohr's atomic model that is shown in textbooks corresponds historically and epistemologically to scientific activity and what the possible deformations are that, coming from this model, are made to the scientific activity that comes from the transposition. The research results show differences between what Bohr (1913 proposed and the transposition of the model in textbooks. This information will contribute to the analysis that is being done regarding the dependability of textbooks.
De novo nonsense mutations in ASXL1 cause Bohring-Opitz syndrome
DEFF Research Database (Denmark)
Hoischen, Alexander; van Bon, Bregje W M; Rodríguez-Santiago, Benjamín;
2011-01-01
Bohring-Opitz syndrome is characterized by severe intellectual disability, distinctive facial features and multiple congenital malformations. We sequenced the exomes of three individuals with Bohring-Opitz syndrome and in each identified heterozygous de novo nonsense mutations in ASXL1, which...
The quest for reality Bohr and Wittgenstein : two complementary views
Stenholm, Stig
2015-01-01
In both science and philosophy, the twentieth century saw a radical breakdown of certainty in the human worldview, as quantum uncertainty and linguistic ambiguity destroyed the comfortable certitudes of the past. As these disciplines form the foundation for a human position in the world, a major epistemological reorganization had to take place. In this book, quantum theorist Stig Stenholm presents Bohr and Wittgenstein, in physics and in philosophy, as central figures representing this revision. Each of them took up the challenge of replacing apparent order and certainty with a provisional understanding based on limited concepts in constant flux. Stenholm concludes that the modern synthesis created by their heirs is far from satisfactory, and the story is so far an unfinished one. The book will appeal to any researcher in either discipline curious about the foundation of modern science, and works to provoke a renewal of discussion, and the eventual emergence of a reformed clarity and understanding.
Systematic Measurements of the Bohr-Weisskopf Effect at ISOLDE
Nojiri, Y; Matsuki, S; Ragnarsson, I; Neugart, R; Redi, O; Stroke, H H; Duong, H T; Marescaux, D; Pinard, J; Juncar, P; Ekstrom, C; Pellarin, M; Vialle, J-L; Inamura, T
2002-01-01
The " Bohr-Weisskopf " effect, or " hyperfine structure (hfs) anomaly ", which results from the effect of the distribution of nuclear magnetization on the electro-nuclear interaction, will be measured systematically at the PS Booster ISOLDE, first for a long chain of radioactive cesium isotopes, analogously to previous isotope shift and hfs studies. In addition to the direct measurement of magnetic moment values, the results are expected to provide independent data for testing nuclear wavefunctions, these will be of importance for interpreting systematic parity non-conservation experiments, complementary to the single isotope study which requires a high precision knowledge of the electron wavefunction. Substantial progress in these calculations has been achieved recently. Precision measurements of the hfs splittings and nuclear magnetic moments are required, with sensitivity adequate for the radioactive isotopes produced. A triple resonance atomic beam magnetic resonance apparatus (Figure 1) with optical pump...
Systematic Measurements of the Bohr-Weisskopf Effect at ISOLDE
2002-01-01
Nuclear electric and magnetic structure properties are measurable by high-resolution atomic spectroscopy through isotope shifts and the Bohr-Weisskopf effect (hyperfine structure anomalies). \\\\ \\\\ The greatest value of these measurements is when made systematically over a large number of isotopes. This has been done in the case of isotopes shifts most extensively by the experiment at ISOLDE. To date the magnetic distribution studies are few and isolated. Here we propose to intitiate a program at ISOLDE to measure hfs anomalies systematically. The experiments, requiring high-precision data on magnetic dipole constants as well as on nuclear g-factors, will be done by atomic-beam magnetic resonance with the use of laser excitation for polarization of the beam and a sixpole magnet acting as an analyser. \\\\ \\\\ The heavy alkali elements are the most promising candidates for hfs anomaly studies because of the large effect expected, the high production yields at ISOLDE and most importantly, the interesting variations...
关于算子形式的Bohr不等式的推广%The Generalization of Bohr inequality for Operator
Institute of Scientific and Technical Information of China (English)
连铁艳; 成立花
2011-01-01
Using the approaches and techniques of operator theory, the generalization of Bohr inequality for bounded and linear operator is researched. Some operator inequalities are given, and then the results of [4 -5 ] are promoted. Moreover, the norm form for Bohr inequality is studied, the relative result of [6] can be obtained.%采用算子论中的方法和技巧,研究了Bohr不等式的有界线性算子形式的推广,并且给出一些算子不等式,这样对文[4-5]中的结果进行了推广.进一步研究了Bohr不等式在算子范数上的性质,推广了文[6]中的相关结果.
单位球Bn上的Bohr不等式%Bohr's Inequality on the Unit Ball Bn
Institute of Scientific and Technical Information of China (English)
王建飞; 刘太顺
2007-01-01
Bohr's type inequalities are studied in this paper: if / is a holomorphic mapping from the unit ball Bn to B", /(O) = p, then we have ∞∑k=0|Dψp(P)[Dkf(0)(zk)]|k!||Dψp(p)||＜1 for |z|＜ max{1/2+|p|,√1-|p|/2} and ψp ∈ Aut(Bn) such that ψp (p) = 0. As corollaries of theabove estimate, we obtain some sharp Bohr's type modulus inequalities. In particular, whenn=1 and |P| →1, then our theorem reduces to a classical result of Bohr.
Heyrovska, R
2005-01-01
Sommerfeld introduced the fine-structure constant into physics, while he was taking into account the relativistic effects in the theory of the hydrogen atom. Ever since, it has puzzled many scientists like Eddington, Dirac, Feynman and others. Here the mysterious fine-structure constant, alpha = (Compton wavelength/de Broglie wavelength) = 1/137.036 = 2.627/360 is interpreted based on the finding that it is close to 2.618/360 = 1/137.508, where the Compton wavelength for hydrogen is a distance equivalent to an arc length on the circumference (given by the de Broglie wavelength) of a circle with the Bohr radius and 2.618 is the square of the Golden ratio, which was recently shown to divide the Bohr radius into two Golden sections at the point of electrical neutrality. From the data for the electron (e) and proton (p) g-factors, it is found that (137.508 - 137.036)= 0.472 = [g(p) - g(e)]/[g(p) + g(e)] (= 2/cube of the Golden ratio), and that (2.627 - 2.618)/360 = (small part of the Compton wavelength correspond...
Placing molecules with Bohr radius resolution using DNA origami
Funke, Jonas J.; Dietz, Hendrik
2016-01-01
Molecular self-assembly with nucleic acids can be used to fabricate discrete objects with defined sizes and arbitrary shapes. It relies on building blocks that are commensurate to those of biological macromolecular machines and should therefore be capable of delivering the atomic-scale placement accuracy known today only from natural and designed proteins. However, research in the field has predominantly focused on producing increasingly large and complex, but more coarsely defined, objects and placing them in an orderly manner on solid substrates. So far, few objects afford a design accuracy better than 5 nm, and the subnanometre scale has been reached only within the unit cells of designed DNA crystals. Here, we report a molecular positioning device made from a hinged DNA origami object in which the angle between the two structural units can be controlled with adjuster helices. To test the positioning capabilities of the device, we used photophysical and crosslinking assays that report the coordinate of interest directly with atomic resolution. Using this combination of placement and analysis, we rationally adjusted the average distance between fluorescent molecules and reactive groups from 1.5 to 9 nm in 123 discrete displacement steps. The smallest displacement step possible was 0.04 nm, which is slightly less than the Bohr radius. The fluctuation amplitudes in the distance coordinate were also small (±0.5 nm), and within a factor of two to three of the amplitudes found in protein structures.
Srinivasan, R
2005-01-01
The Bohr Complementarity Principle (BCP) holds in Afshar's experiment under the newly proposed NAFL (non-Aristotelian finitary logic) interpretation of quantum mechanics. NAFL requires that no `physical' reality can be ascribed to the wave nature of a single photon. The NAFL theory QM, formalizing quantum mechanics, treats the superposed state ($S$) of a single photon taking two or more different paths at the same time as a logical contradiction that is formally unprovable in QM. Nevertheless, in a non-classical NAFL model for QM in which the law of non-contradiction fails, $S$ has a meaningful metamathematical interpretation that the photon has not been measured (or axiomatically declared) to take any particular path available to it. It is argued that even the existence of an interference pattern does not logically amount to a proof that a single photon exhibits self-interference. Since QM does not prove the existence of the state $S$, it follows that one can retroactively infer, from a measurement $Q$ made ...
Why has the bohr-sommerfeld model of the atom been ignoredby general chemistry textbooks?
Niaz, Mansoor; Cardellini, Liberato
2011-12-01
Bohr's model of the atom is considered to be important by general chemistry textbooks. A major shortcoming of this model was that it could not explain the spectra of atoms containing more than one electron. In order to increase the explanatory power of the model, Sommerfeld hypothesized the existence of elliptical orbits. This study has the following objectives: 1) Formulation of criteria based on a history and philosophy of science framework; and 2) Evaluation of university-level general chemistry textbooks based on the criteria, published in Italy and U.S.A. Presentation of a textbook was considered to be "satisfactory" if it included a description of the Bohr-Sommerfeld model along with diagrams of the elliptical orbits. Of the 28 textbooks published in Italy that were analyzed, only five were classified as "satisfactory". Of the 46 textbooks published in U.S.A., only three were classified as "satisfactory". This study has the following educational implications: a) Sommerfeld's innovation (auxiliary hypothesis) by introducing elliptical orbits, helped to restore the viability of Bohr's model; b) Bohr-Sommerfeld's model went no further than the alkali metals, which led scientists to look for other models; c) This clearly shows that scientific models are tentative in nature; d) Textbook authors and chemistry teachers do not consider the tentative nature of scientific knowledge to be important; e) Inclusion of the Bohr-Sommerfeld model in textbooks can help our students to understand how science progresses.
Applications of Bohr's correspondence principle
Energy Technology Data Exchange (ETDEWEB)
Crawford, F. S.
1989-07-01
The Bohr correspondence-principle (cp) formula /ital dE///ital dn/=/h bar/..omega.. is presented (..omega.. is the classical angular frequency) and its predicted energy levels /ital E//sub /ital n// are compared to those given by the stationary state solutions of the Schr/umlt o/dinger equation, first for several examples in one dimension (1D), including the ''quantum bouncer,'' and then for several examples in three dimensions (3D), including the hydrogen atom and the isotropic harmonic oscillator. For the 3-D cases, the cp predictions based on classical circular orbits are compared with the ''circlelike'' Schr/umlt o/dinger solutions (those with the lowest energy eigenvalue for a given /ital l/) and the cp predictions based on classical ''needle'' orbits (having zero angular momentum) with the Schr/umlt o/dinger /ital l/=0 solutions. For the H atom and the isotropic oscillator, the cp prediction does not depend on the classical orbit chosen because of a ''degeneracy'': the fact that for these systems ..omega.. is independent of the orbit. As a more stringent test of the cp, analogous nondegenerate systems /ital V/=/minus//ital k///ital r//sup 3/2/ in place of the H-atom potential /ital V/=/minus//ital e//sup 2///ital r/ and /ital V/=/ital kr//sup 4/ in place of the oscillator potential /ital V/=(1/2)/ital m/..omega../sup 2//ital r2/ are therefore considered. Aninteresting anomaly that occurs for the harmonic oscillator and itsnondegenerate analog /ital V/=/ital kr//sup 4/ is encountered (but not for the H atomnor its nondegenerate analog /ital V/=/minus//ital k///ital r//sup 3/2/), wherein half of thestates predicted by application of the cp to the needle orbits are ''spurious''in that there are no corresponding Schr/umlt o/dinger /ital l/=0 states.
Probing the (empirical quantum structure embedded in the periodic table with an effective Bohr model
Directory of Open Access Journals (Sweden)
Wellington Nardin Favaro
2013-01-01
Full Text Available The atomic shell structure can be observed by inspecting the experimental periodic properties of the Periodic Table. The (quantum shell structure emerges from these properties and in this way quantum mechanics can be explicitly shown considering the (semi-quantitative periodic properties. These periodic properties can be obtained with a simple effective Bohr model. An effective Bohr model with an effective quantum defect (u was considered as a probe in order to show the quantum structure embedded in the Periodic Table. u(Z shows a quasi-smoothed dependence of Z, i.e., u(Z ≈ Z2/5 - 1.
Atomically thin spherical shell-shaped superscatterers based on a Bohr model.
Li, Rujiang; Lin, Xiao; Lin, Shisheng; Liu, Xu; Chen, Hongsheng
2015-12-18
Graphene monolayers can be used for atomically thin three-dimensional shell-shaped superscatterer designs. Due to the excitation of the first-order resonance of transverse magnetic (TM) graphene plasmons, the scattering cross section of the bare subwavelength dielectric particle is enhanced significantly by five orders of magnitude. The superscattering phenomenon can be intuitively understood and interpreted with a Bohr model. In addition, based on the analysis of the Bohr model, it is shown that contrary to the TM case, superscattering is hard to achieve by exciting the resonance of transverse electric (TE) graphene plasmons due to their poor field confinements.
Exactly separable Bohr Hamiltonian with the Killingbeck potential for triaxial nuclei
Neyazi, H.; Rajabi, A. A.; Hassanabadi, H.
2016-01-01
After pioneering work by Bohr, Mottelson and their numerous colleagues, the essential framework for understanding collective model is introduced. One of the applications of this framework is the study of shape phase transition, vibrational and rotational energy spectrum of nuclei. We consider the Bohr Hamiltonian and solve the beta and gamma part equation of it, by considering that reduced potential and wave function are exactly separable. In the beta part equation we consider the Killingbeck potential and derive the wave function and energy spectrum of it.
New Derivation for Bohr Hamiltonian%Bohr哈密顿量的新推导
Institute of Scientific and Technical Information of China (English)
郭建友; 徐辅新; 阮图南
2000-01-01
We present an altemative approach for deriving the Bohr Hamiltonian, which is based on the quantized procedure proposed by Lee. The merit of this approach is the explicit form of the rotational operators is obtained with the corresponding rotational inertia.%利用李政道先生的正则量子化程序，给出了一个新的方法导出了Bohr 哈密顿量，并给出了转动算符和转动惯量的明显表达式。
Atomically thin spherical shell-shaped superscatterers based on Bohr model
Li, Rujiang; Lin, Shisheng; Liu, Xu; Chen, Hongsheng
2015-01-01
Graphene monolayers can be used for atomically thin three-dimensional shell-shaped superscatterer designs. Due to the excitation of the first-order resonance of transverse magnetic (TM) graphene plasmons, the scattering cross section of the bare subwavelength dielectric particle is enhanced significantly by five orders of magnitude. The superscattering phenomenon can be intuitively understood and interpreted with Bohr model. Besides, based on the analysis of Bohr model, it is shown that contrary to the TM case, superscattering is hard to occur by exciting the resonance of transverse electric (TE) graphene plasmons due to their poor field confinements.
Institute of Scientific and Technical Information of China (English)
李明亮; 徐辅新
2003-01-01
在利用Harris两参数公式研究Bohr-Mottelson转动谱公式参数之间的关系的基础上,改用Harris三参数公式,并由此提出了Bohr-Mottelson转动谱公式参数之间的新关系式,进而用I(I+1)四参数展开式计算了A～60,80,130,140,150,190区超形变偶偶核的基带和锕系和稀土区正常形变核基带,讨论了参数之间的关系,发现新关系式与实验较好地符合.
The Bohr Correspondence Principle: Kepler Orbits of the Electron in a Hydrogen Atom
Indian Academy of Sciences (India)
2016-06-01
We consider the quantum-mechanical non-relativistichydrogen atom. We show that for boundstates with size much larger than the Bohr radius,one can construct a wave packet that is localizedin space corresponding to a classical particlemoving in a circular orbit.
Buganu, Petricǎ; Fortunato, Lorenzo
2016-09-01
We review and discuss several recent approaches to quadrupole collectivity and developments of collective models and their solutions with many applications, examples and references. We focus in particular on analytic and approximate solutions of the Bohr hamiltonian of the last decade, because most of the previously published material has been already reviewed in other publications.
What Can the Bohr-Sommerfeld Model Show Students of Chemistry in the 21st Century?
Niaz, Mansoor; Cardellini, Liberato
2011-01-01
Bohr's model of the atom is considered to be important by general chemistry textbooks. A shortcoming of this model was that it could not explain the spectra of atoms containing more than one electron. To increase the explanatory power of the model, Sommerfeld hypothesized the existence of elliptical orbits. This study aims to elaborate a framework…
Why We Should Teach the Bohr Model and How to Teach it Effectively
McKagan, S. B.; Perkins, K. K.; Wieman, C. E.
2008-01-01
Some education researchers have claimed that we should not teach the Bohr model of the atom because it inhibits students' ability to learn the true quantum nature of electrons in atoms. Although the evidence for this claim is weak, many have accepted it. This claim has implications for how to present atoms in classes ranging from elementary school…
La filosofía trascendental y la interpretación de Bohr de la teoría cuántica
Directory of Open Access Journals (Sweden)
Hernán Pringe
2012-01-01
Full Text Available La filosofía trascendental de Kant distingue entre las condiciones de objetividad del conocimiento y las de la unidad sistemática de éste. En el presente artículo, intentaremos mostrar que esos dos momentos del conocimiento científico constituyen los ejes que articulan la interpretación de Bohr de la teoría cuántica. Veremos que la exigencia de objetividad del conocimiento fundamentará el carácter clásico de la descripción de los fenómenos cuánticos, mientras que la demanda de unidad sistemática de dichos fenómenos fundamentará la objetividad de los objetos cuánticos.Kant's transcendental philosophy makes a distinction between the conditions of objectivity of knowledge and those of its systematic unity. In this article we aim to show that these two moments of scientific knowledge articulate Bohr´s interpretation of quantum theory. We shall see that the demand of objectivity of knowledge grounds the classical character of the description of quantum phenomena, while the demand of their systematic unity grounds the objectivity of quantum objects.
Does God Play Dice with Universe The Hydrogen Atomic Model of Bohr and de Broglie
Kamenov, P S
1999-01-01
In this paper it is shown that if one accept assumption of de Broglie that "unitary wave-particle" exists simultaneously and this coexistence is real, then one can find the mean life time of the hydrogen atom of Bohr (intensities). Something more, the acceptance of de Broglie's ideas show that a single excited hydrogen atom decays at exactly predictable moment (after excitation). The natural width of excited hydrogen atoms are found using the Bohr's model of this atom and de Broglie's ideas. The mean life time of the excited states is a characteristic only of a statistical ensemble of many atoms and coincide exactly with experimental data and can be used for analytical applications. It is shown also that resonant Mossbauer absorption in time domain provides a qualitative evidence of the existence of "own lifetime" for first excited states of the nuclei.
Virtual Visit to the ATLAS Control Room by Niels Bohr Institute - Kulturnatten, Copenhagen
ATLAS Experiment
2012-01-01
This ATLAS Virtual Visit will be part of outreach and education programme of the Niels Bohr Institute during a Copenhagen wide night of culture and science, Kulturnatten. Visitors of all ages and background will have the chance to get an introduction to the ATLAS Experiment, the LHC, and basic particle physics. The Virtual Visit will supplement an exhibition and give the opportunity to ask questions about anything related to ATLAS to a Danish physicist at CERN. The Niels Bohr Institute is a long time member of the ATLAS Collaboration and has contributed to Kulturnatten for many years now. http://atlas-live-virtual-visit.web.cern.ch/atlas-live-virtual-visit/2012/Copenhagen-2012.html
Research on superdeformed bands with Bohr-Mottelson's formulas%Bohr-Mottelson公式对超形变带的比较研究
Institute of Scientific and Technical Information of China (English)
叶剑; 方向正; 郭建友
2006-01-01
用Bohr-Mottelson的两参数、三参数和四参数公式对150区30条超形变带进行了系统分析.结果显示:三个公式都能较好地拟合150区超形变带的E2跃迁谱,而且带首自旋的确定基本一致.大部分带Bohr-Mottelson的三参数数值关系符合ab公式的理论预期值,小部分带的三参数数值关系符合Harris公式的理论预期值.一半以上带的四参数数值关系与ab公式的预期值接近,而与Harris公式的预期值偏离较大.表明两参数ab公式比Harris公式具有更广泛的实用性.
Research on Superdeformed Bands with Bohr-Mottelson's Formulas%Bohr-Mottelson公式对超形变带的比较研究
Institute of Scientific and Technical Information of China (English)
郭建友; 徐辅新; 阮图南
2000-01-01
用Bohr-Mottelson的两参数、三参数和四参数公式对A～190区61条超形变带进行了系统分析. 结果显示:3个公式都能较好地拟合190区超形变带的E2跃迁谱,而且带首自旋的确定基本一致. 大部分带Bohr-Mottelson的三参数数值关系符合ab公式的理论预期值,小部分带的三参数数值关系符合Harris公式的理论预期值. 一半以上带的四参数数值关系与ab公式的预期值接近,而与Harris公式的预期值偏离较大. 表明两参数ab公式比Harris公式具有更广泛的实用性.
Sprinzak, D.; Buks, E.; Heiblum, M.; Shtrikman, H.
1999-01-01
Interference results when a quantum particle is free to choose among a few indistinguishable paths. A canonical example of Bohr's complementarity principle [1] is a two-path interferometer with an external detector coupled to one of the paths. Then, interference between the two paths vanishes (i.e. dephasing) if one is able to detect, even in principle, the path taken by the particle. This type of which path (WP) experiment was already executed with photons, cooled atoms, neutrons, solitons, ...
Bohr-Sommerfeld quantization condition for Dirac states derived from an Ermakov-type invariant
Energy Technology Data Exchange (ETDEWEB)
Thylwe, Karl-Erik [KTH-Mechanics, Royal Institute of Technology, S-10044 Stockholm (Sweden); McCabe, Patrick [CCDC, 12 Union Road, CB2 1EZ Cambridge (United Kingdom)
2013-05-15
It is shown that solutions of the second-order decoupled radial Dirac equations satisfy Ermakov-type invariants. These invariants lead to amplitude-phase-type representations of the radial spinor solutions, with exact relations between their amplitudes and phases. Implications leading to a Bohr-Sommerfeld quantization condition for bound states, and a few particular atomic/ionic and nuclear/hadronic bound-state situations are discussed.
Inversion of the Bohr effect upon oxygen binding to 24-meric tarantula hemocyanin.
Sterner, R; Decker, H
1994-01-01
The Bohr effect describes the usually negative coupling between the binding of oxygen and the binding of protons to respiratory proteins. It was first described for hemoglobin and provides for an optimal oxygen supply of the organism under changing physiological conditions. Our measurements of both oxygen and proton binding to the 24-meric tarantula hemocyanin establish the unusual case where a respiratory protein binds protons at low degrees of oxygenation but releases protons at high degree...
Why we should teach the Bohr model and how to teach it effectively
Directory of Open Access Journals (Sweden)
S. B. McKagan
2008-03-01
Full Text Available Some education researchers have claimed that we should not teach the Bohr model of the atom because it inhibits students’ ability to learn the true quantum nature of electrons in atoms. Although the evidence for this claim is weak, many have accepted it. This claim has implications for how to present atoms in classes ranging from elementary school to graduate school. We present results from a study designed to test this claim by developing a curriculum on models of the atom, including the Bohr and Schrödinger models. We examine student descriptions of atoms on final exams in transformed modern physics classes using various versions of this curriculum. We find that if the curriculum does not include sufficient connections between different models, many students still have a Bohr-like view of atoms rather than a more accurate Schrödinger model. However, with an improved curriculum designed to develop model-building skills and with better integration between different models, it is possible to get most students to describe atoms using the Schrödinger model. In comparing our results with previous research, we find that comparing and contrasting different models is a key feature of a curriculum that helps students move beyond the Bohr model and adopt Schrödinger’s view of the atom. We find that understanding the reasons for the development of models is much more difficult for students than understanding the features of the models. We also present interactive computer simulations designed to help students build models of the atom more effectively.
Are we living in a quantum world? Bohr and quantum fundamentalism
Zinkernagel, Henrik
2016-01-01
The spectacular successes of quantum physics have made it a commonplace to assert that we live in a quantum world. This idea seems to imply a kind of "quantum fundamentalism" according to which everything in the universe (if not the universe as a whole) is fundamentally of a quantum nature and ultimately describable in quantum-mechanical terms. Bohr's conception of quantum mechanics has traditionally been seen as opposed to such a view, not least because of his insistence on the necessity of the concepts of classical physics in the account of quantum phenomena. Recently, however, a consensus seems to be emerging among careful commentators on Bohr to the effect that he, after all, did subscribe to some version of quantum fundamentalism. Against this consensus, and by re-examining the historical record, I will defend a variant of the traditional reading of Bohr in which (1) the answer to what an object is (quantum or classical) depends on the experimental context; and (2) in principle, any physical system can b...
Des images et des paraboles : Niels Bohr et le discours descriptif en physique quantique
Directory of Open Access Journals (Sweden)
Ilias Yocaris
2011-01-01
Full Text Available Cette étude porte sur l’importance accordée aux images verbales dans le discours descriptif utilisé en mécanique quantique, et plus précisément sur la conception de la langue scientifique qui est celle de Niels Bohr (1885-1962 : en raison d’une série de considérations techniques, méthodologiques et épistémologiques que nous nous proposons d’analyser in extenso, Bohr considère effectivement que les phénomènes subatomiques ne peuvent être évoqués directement (sans référence au contexte observationnel, par le biais d’un langage dénotatif non figural, mais uniquement de manière métaphorique, détournée, ce qui réduit à ses yeux le discours descriptif des physiciens à « des images et des paraboles ». En examinant les textes de Bohr à la lumière d’un certain nombre de travaux épistémologiques, de commentaires et d’expérimentations auxquels ils ont donné lieu ultérieurement, nous nous proposons de décrire les implications conceptuelles d’une telle prise de position, qui constitue une vraie révolution sur le plan philosophique.
Why we should teach the Bohr model and how to teach it effectively
McKagan, S B; Wieman, C E
2007-01-01
Some education researchers have claimed that we should not teach the Bohr model of the atom because it inhibits students' ability to learn the true quantum nature of electrons in atoms. Although the evidence for this claim is weak, many have accepted it. This claim has implications for how to present atoms in classes ranging from elementary school to graduate school. We present results from a study designed to test this claim by developing curriculum on models of the atom, including the Bohr and Schrodinger models. We examine student descriptions of atoms on final exams in transformed modern physics classes using various versions of this curriculum. We find that if the curriculum does not include sufficient connections between different models, many students still have a Bohr-like view of atoms, rather than a more accurate Schrodinger model. However, with an improved curriculum designed to develop model-building skills and with better integration between different models, it is possible to get nearly all stud...
Bohr-Mottelson转动谱公式的参数研究%Research on prameters of Bohr-Mottelson rotational spectra formula
Institute of Scientific and Technical Information of China (English)
徐辅新; 李明亮; 温亚媛
2002-01-01
利用Bohr-Mottelson的I(I+1)四参数展开式分析了A～150,190偶偶核超形变带和锕系、稀土区偶偶核正常形变转动带.由最小二乘法拟合计算出参数,讨论参数之间的关系,发现ab公式、abc公式和Harris公式的预言存在不同程度的偏离.但相对而言,ab公式、abc公式的预言较好.而且超形变带的参数关系和正常形变带相似.
Redox Bohr effects and the role of heme a in the proton pump of bovine heart cytochrome c oxidase.
Capitanio, Giuseppe; Martino, Pietro Luca; Capitanio, Nazzareno; Papa, Sergio
2011-10-01
Structural and functional observations are reviewed which provide evidence for a central role of redox Bohr effect linked to the low-spin heme a in the proton pump of bovine heart cytochrome c oxidase. Data on the membrane sidedness of Bohr protons linked to anaerobic oxido-reduction of the individual metal centers in the liposome reconstituted oxidase are analysed. Redox Bohr protons coupled to anaerobic oxido-reduction of heme a (and Cu(A)) and Cu(B) exhibit membrane vectoriality, i.e. protons are taken up from the inner space upon reduction of these centers and released in the outer space upon their oxidation. Redox Bohr protons coupled to anaerobic oxido-reduction of heme a(3) do not, on the contrary, exhibit vectorial nature: protons are exchanged only with the outer space. A model of the proton pump of the oxidase, in which redox Bohr protons linked to the low-spin heme a play a central role, is described. This article is part of a Special Issue entitled: Allosteric cooperativity in respiratory proteins.
Bohr effect and temperature sensitivity of hemoglobins from highland and lowland deer mice.
Jensen, Birgitte; Storz, Jay F; Fago, Angela
2016-05-01
An important means of physiological adaptation to environmental hypoxia is an increased oxygen (O2) affinity of the hemoglobin (Hb) that can help secure high O2 saturation of arterial blood. However, the trade-off associated with a high Hb-O2 affinity is that it can compromise O2 unloading in the systemic capillaries. High-altitude deer mice (Peromyscus maniculatus) have evolved an increased Hb-O2 affinity relative to lowland conspecifics, but it is not known whether they have also evolved compensatory mechanisms to facilitate O2 unloading to respiring tissues. Here we investigate the effects of pH (Bohr effect) and temperature on the O2-affinity of high- and low-altitude deer mouse Hb variants, as these properties can potentially facilitate O2 unloading to metabolizing tissues. Our experiments revealed that Bohr factors for the high- and low-altitude Hb variants are very similar in spite of the differences in O2-affinity. The Bohr factors of deer mouse Hbs are also comparable to those of other mammalian Hbs. In contrast, the high- and low-altitude variants of deer mouse Hb exhibited similarly low temperature sensitivities that were independent of red blood cell anionic cofactors, suggesting an appreciable endothermic allosteric transition upon oxygenation. In conclusion, high-altitude deer mice have evolved an adaptive increase in Hb-O2 affinity, but this is not associated with compensatory changes in sensitivity to changes in pH or temperature. Instead, it appears that the elevated Hb-O2 affinity in high-altitude deer mice is compensated by an associated increase in the tissue diffusion capacity of O2 (via increased muscle capillarization), which promotes O2 unloading.
van Dongen, Jeroen
2015-01-01
The Einstein-Rupp experiments have been unduly neglected in the history of quantum mechanics. While this is to be explained by the fact that Emil Rupp was later exposed as a fraud and had fabricated the results, it is not justified, due to the importance attached to the experiments at the time. This paper discusses Rupp's fraud, the relation between Albert Einstein and Rupp, and the Einstein-Rupp experiments, and argues that these experiments were an influence on Niels Bohr's development of c...
El modelo atómico de Bohr: una aplicación
Raul Garcia Llamas
2013-01-01
Se aplica la teoría atómica de Bohr cuyo centenario se celebra este 2013, utilizando la aproximación electrostática y un algoritmo numérico para resolver las ecuaciones clásicas de movimiento del núcleo y de los electrones en átomos complejos, con el fin de estudiar su dinámica. Se presentan resultados numéricos para el caso del átomo de Hidrogeno y el átomo de Helio.
Exactly separable version of the Bohr Hamiltonian with the Davidson potential
Bonatsos, Dennis; McCutchan, E. A.; Minkov, N.; Casten, R. F.; Yotov, P.; Lenis, D.; Petrellis, D.; Yigitoglu, I.
2008-01-01
An exactly separable version of the Bohr Hamiltonian is developed using a potential of the form u(beta)+u(gamma)/beta^2, with the Davidson potential u(beta)= beta^2 + beta_0^4/beta^2 (where beta_0 is the position of the minimum) and a stiff harmonic oscillator for u(gamma) centered at gamma=0. In the resulting solution, called exactly separable Davidson (ES-D), the ground state band, gamma band and 0_2^+ band are all treated on an equal footing. The bandheads, energy spacings within bands, an...
Bohr Hamiltonian with Hulth?en plus Ring shaped potential for triaxial nuclei
Chabab, M; Oulne, M
2015-01-01
In this paper, we solve the eigenvalues and eigenvectors problem with Bohr collective Hamil- tonian for triaxial nuclei. The ? beta part of the collective potential is taken to be equal to Hulth?en potential while the gamma part is de?ned by a new generalized potential obtained from a ring shaped one. Analytical expressions for spectra and wave functions are derived by means of a recent version of the asymptotic iteration method and the usual approximations. The calculated energies and B(E2) transition rates are compared with experimental data and the available theoretical results in the literature.
El modelo atómico de Bohr: una aplicación
Directory of Open Access Journals (Sweden)
Raul Garcia Llamas
2013-06-01
Full Text Available Se aplica la teoría atómica de Bohr cuyo centenario se celebra este 2013, utilizando la aproximación electrostática y un algoritmo numérico para resolver las ecuaciones clásicas de movimiento del núcleo y de los electrones en átomos complejos, con el fin de estudiar su dinámica. Se presentan resultados numéricos para el caso del átomo de Hidrogeno y el átomo de Helio.
van Dongen, Jeroen
2015-01-01
The Einstein-Rupp experiments have been unduly neglected in the history of quantum mechanics. While this is to be explained by the fact that Emil Rupp was later exposed as a fraud and had fabricated the results, it is not justified, due to the importance attached to the experiments at the time. This paper discusses Rupp's fraud, the relation between Albert Einstein and Rupp, and the Einstein-Rupp experiments, and argues that these experiments were an influence on Niels Bohr's development of complementarity and Werner Heisenberg's formulation of the uncertainty relations.
Parameter-Free Solution of the Bohr Hamiltonian for Actinides Critical in the Octupole Mode
Lenis, D; Bonatsos, Dennis
2006-01-01
An analytic, parameter-free (up to overall scale factors) solution of the Bohr Hamiltonian involving axially symmetric quadrupole and octupole deformations, as well as an infinite well potential, is obtained, after separating variables in a way reminiscent of the Variable Moment of Inertia (VMI) concept. Normalized spectra and B(EL) ratios are found to agree with experimental data for 226-Ra and 226-Th, the nuclei known to lie closest to the border between octupole deformation and octupole vibrations in the light actinide region.
Comment on breakdown of Bohr's Correspondence Principle by Bo Gao, In
Tannous, C
2001-01-01
Gao applied LeRoy and Bernstein semi-classical analysis for the energy levels in a potential of the form -C/r^n to sequences of scaled energy differences progressing towards low lying states and found a better agreement with the semi-classical prediction. We checked that for the energy levels obtained by Stwalley et al. with the same potential, the agreement with the semi-classical approximation is better for higher vibrational quantum numbers in agreement with Bohr's correspondence principle.
Electric quadrupole transitions of the Bohr Hamiltonian with Manning-Rosen potential
Chabab, M; Lahbas, A; Oulne, M
2016-01-01
Analytical expressions of the wave functions are derived for a Bohr Hamiltonian with the Manning{Rosen potential in the cases of {\\gamma}-unstable nuclei and axially symmetric prolate deformed ones with {\\gamma}=0. By exploiting the results we have obtained in a recent work on the same theme Ref. [1], we have calculated the B(E2) transition rates for 34 {\\gamma}-unstable and 38 rotational nuclei and compared to experimental data, revealing a qualitative agreement with the experiment and phase transitions within the ground state band and showing also that the Manning-Rosen potential is more appropriate for such calculations than other potentials.
Electric quadrupole transitions of the Bohr Hamiltonian with Manning-Rosen potential
Chabab, M.; El Batoul, A.; Lahbas, A.; Oulne, M.
2016-09-01
Analytical expressions of the wave functions are derived for a Bohr Hamiltonian with the Manning-Rosen potential in the cases of γ-unstable nuclei and axially symmetric prolate deformed ones with γ ≈ 0. By exploiting the results we have obtained in a recent work on the same theme Ref. [1], we have calculated the B (E 2) transition rates for 34 γ-unstable and 38 rotational nuclei and compared to experimental data, revealing a qualitative agreement with the experiment and phase transitions within the ground state band and showing also that the Manning-Rosen potential is more appropriate for such calculations than other potentials.
Bohr Hamiltonian with Hulthen plus ring-shaped potential for triaxial nuclei
Energy Technology Data Exchange (ETDEWEB)
Chabab, M.; Lahbas, A.; Oulne, M. [Cadi Ayyad University, High Energy Physics and Astrophysics Laboratory, Department of Physics, Faculty of Sciences Semlalia, P. O. B. 2390, Marrakesh (Morocco)
2015-10-15
In this paper, we solve the eigenvalues and eigenvectors problem with the Bohr collective Hamiltonian for triaxial nuclei. The β-part of the collective potential is taken to be equal to the Hulthen potential while the γ-part is defined by a new generalized potential obtained from a ring-shaped one. Analytical expressions for spectra and wave functions are derived by means of a recent version of the asymptotic iteration method and the usual approximations. The calculated energies and B(E2) transition rates are compared with experimental data and the available theoretical results in the literature. (orig.)
The influence of Niels Bohr on Max Delbrück: revisiting the hopes inspired by "light and life".
McKaughan, Daniel J
2005-12-01
The impact of Niels Bohr's 1932 "Light and Life" lecture on Max Delbrück's lifelong search for a form of "complementarity" in biology is well documented and much discussed, but the precise nature of that influence remains subject to misunderstanding. The standard reading, which sees Delbrück's transition from physics into biology as inspired by the hope that investigation of biological phenomena might lead to a breakthrough discovery of new laws of physics, is colored much more by Erwin Schrödinger's What Is Life? (1944) than is often acknowledged. Bohr's view was that teleological and mechanistic descriptions are mutually exclusive yet jointly necessary for an exhaustive understanding of life. Although Delbrück's approach was empirical and less self-consciously philosophical, he shared Bohr's hope that scientific investigation would vindicate the view that at least some aspects of life are not reducible to physico-chemical terms.
Exactly separable version of the Bohr Hamiltonian with the Davidson potential
Bonatsos, Dennis; Minkov, N; Casten, R F; Yotov, P; Lenis, D; Petrellis, D; Yigitoglu, I
2007-01-01
An exactly separable version of the Bohr Hamiltonian is developed using a potential of the form u(beta)+u(gamma)/beta^2, with the Davidson potential u(beta)= beta^2 + beta_0^4/beta^2 (where beta_0 is the position of the minimum) and a stiff harmonic oscillator for u(gamma) centered at gamma=0. In the resulting solution, called exactly separable Davidson (ES-D), the ground state band, gamma band and 0_2^+ band are all treated on an equal footing. The bandheads, energy spacings within bands, and a number of interband and intraband B(E2) transition rates are well reproduced for almost all well-deformed rare earth and actinide nuclei using two parameters (beta_0, gamma stiffness). Insights regarding the recently found correlation between gamma stiffness and the gamma-bandhead energy, as well as the long standing problem of producing a level scheme with Interacting Boson Approximation SU(3) degeneracies from the Bohr Hamiltonian, are also obtained.
The boundary conditions for Bohr's law: when is reacting faster than acting?
Pinto, Yaïr; Otten, Marte; Cohen, Michael A; Wolfe, Jeremy M; Horowitz, Todd S
2011-02-01
In gunfights in Western movies, the hero typically wins, even though the villain draws first. Niels Bohr (Gamow, The great physicists from Galileo to Einstein. Chapter: The law of quantum, 1988) suggested that this reflected a psychophysical law, rather than a dramatic conceit. He hypothesized that reacting is faster than acting. Welchman, Stanley, Schomers, Miall, and Bülthoff (Proceedings of the Royal Society of London B: Biological Sciences, 277, 1667-1674, 2010) provided empirical evidence supporting "Bohr's law," showing that the time to complete simple manual actions was shorter when reacting than when initiating an action. Here we probe the limits of this effect. In three experiments, participants performed a simple manual action, which could either be self-initiated or executed following an external visual trigger. Inter-button time was reliably faster when the action was externally triggered. However, the effect disappeared for the second step in a two-step action. Furthermore, the effect reversed when a choice between two actions had to be made. Reacting is faster than acting, but only for simple, ballistic actions. PMID:21264708
DEFF Research Database (Denmark)
Ougaard, Morten
2015-01-01
, ikke mindst med hensyn til værdirelativismen. Rasmussen viser, at komplementaritetsbegrebet i Bohrs vigtige men oversete filosofi kan bidrage væsentligt til at afklare teoretisk-metodiske problemer i statskundskab, herunder forholdet mellem struktur og handling og mellem mikro- og makroanalyse, samt...... ikke mindst forholdet mellem normative og kognitive udsagn. Efter mødet med Niels Bohrs filosofi står Rasmussens værdirelativisme både skarpere og stærkere end før, og Kasper Lippert-Rasmussens karakteristik af denne position som et ubegrundet dogme i dansk politologi er ikke overbevisende....
DEFF Research Database (Denmark)
Hastings, Rob; Cobben, Jan-Maarten; Gillessen-Kaesbach, Gabriele;
2011-01-01
Bohring-Opitz syndrome (BOS) is a rare congenital disorder of unknown etiology diagnosed on the basis of distinctive clinical features. We suggest diagnostic criteria for this condition, describe ten previously unreported patients, and update the natural history of four previously reported patien...
Energy Technology Data Exchange (ETDEWEB)
Fewster, Christopher J [Department of Mathematics, University of York, Heslington, York YO10 5DD (United Kingdom); Sahlmann, Hanno [Spinoza Institute, Universiteit Utrecht (Netherlands)
2008-11-21
We give a definition for the Wigner function for quantum mechanics on the Bohr compactification of the real line and prove a number of simple consequences of this definition. We then discuss how this formalism can be applied to loop quantum cosmology. As an example, we use the Wigner function to give a new quantization of an important building block of the Hamiltonian constraint.
Fewster, C.J.; Sahlmann, H.
2008-01-01
We give a definition for the Wigner function for quantum mechanics on the Bohr compactification of the real line and prove a number of simple consequences of this definition. We then discuss how this formalism can be applied to loop quantum cosmology. As an example, we use the Wigner function to giv
Zhang, Yan; Kobayashi, Keiko; Kitazawa, Kazuki; Imai, Kiyohiro; Kobayashi, Michiyori
2006-01-01
By using published experimental values of the standard oxygen (O2) equilibrium curve and the in vivo arterial and venous O2 pressure (PO2) of fetal and maternal blood in five mammalian species (human, cow, pig, sheep, and horse), we investigated the relationship between the efficiency of O2 delivery and the effectiveness of the Bohr shift, and discussed the significance of cooperativity for mammalian Hb. The O2 delivery of fetal blood was more efficient than that of maternal blood, and the effectiveness of the Bohr shift at both O2 loading and release sites of fetal blood was high. A linear relationship was observed between the efficiency of O2 delivery and the effectiveness of the Bohr shift at O2 loading sites of the five mammalian species. In both fetal and maternal blood, the theoretically obtained optimal P50 value for O2 delivery (optP50(OD)) was nearly equal to the optimal P50 value for the effectiveness of the Bohr shift at the O2 loading site (optP50(BS)(loading)). This phenomenon was favorable for fetal blood to uptake O2 from maternal blood with the aid of the Bohr shift and to deliver a large amount of O2 to the tissues. The optP50s for the effectiveness of the Bohr shift at given arterial PO2 (PaO2) and venous PO2 (PvO2) were derived as follows: optP50(BS)(loading) = PaO2((n+1)/(n-1))(1/n), and optP50(BS)(release) = PvO2((n+1)/(n-1))(1/n). The relationship between in vivo PO2s and n, PaO2/PvO2 = ((n+1)/(n-1))(2/n), was derived by letting optP50 for the efficiency of O2 delivery be equal to that for the effectiveness of the Bohr shift.
The language of Orthodox theology & quantum mechanics: St Gregory Palamas and Niels Bohr
DEFF Research Database (Denmark)
Tanev, Stoyan
2013-01-01
The objective of this chapter is to provide an analytical framework that would enable the comparison of the ways of using words and language in the cases of St. Gregory Palamas and Niels Bohr. The main motivation will be to explore Christos Yannaras’ point about the opportunity of using quantum...... mechanics as a source of a new language that could be useful in enhancing the power of theological statements. It is important to point out that the main goal here is to use the insights from existing studies to provide a preliminary comparative analysis. The novelty in such an approach should be sought...... relevant within the context of Christian homiletics and apologetics and it is precisely this aspect that is of greatest interest here. The discussion will necessarily focus on epistemological issues, touching on the nature of the relation between the meaning of words and the reality they represent...
Bohr Hamiltonian with an energy dependent $\\gamma$-unstable Coulomb-like potential
Budaca, R
2016-01-01
An exact analytical solution for the Bohr Hamiltonian with an energy dependent Coulomb-like $\\gamma$-unstable potential is presented. Due to the linear energy dependence of the potential's coupling constant, the corresponding spectrum in the asymptotic limit of the slope parameter resembles the spectral structure of the spherical vibrator, however with a different state degeneracy. The parameter free energy spectrum as well as the transition rates for this case are given in closed form and duly compared with those of the harmonic $U(5)$ dynamical symmetry. The model wave functions are found to exhibit properties that can be associated to shape coexistence. A possible experimental realization of the model is found in few medium nuclei with a very low second $0^{+}$ state known to exhibit competing prolate, oblate and spherical shapes.
International Nuclear Information System (INIS)
An atomic beam magnetic resonance (ABMR) apparatus has been constructed at Orsay, and has been installed at the CERN PS Booster ISOLDE mass separator facility for 'on-line' work with radioactive isotopes in a program to measure hyperfine structure anomalies (the Bohr-Weisskopf effect) over long isotopic chains. The hfs anomalies result from the effect of the spatial distribution of the nuclear magnetization on the atomic hfs interaction. Constructional details of the system are described: Emphasis is placed on the measurement of nuclear g-factors by a triple resonance, laser state selected, ABMR method. A precision better than 10-4 for gI values has been obtained in stable atomic beam tests, leading to hfs anomaly measurements better than 10%. Two types of detection systems are described: Laser fluorescence and surface ionization coupled with mass spectrometry. (orig.)
Excited collective states of nuclei within Bohr Hamiltonian with Tietz-Hua potential
Chabab, M; Hamzavi, M; Lahbas, A; Oulne, M
2016-01-01
In this paper, we present new analytical solutions of the Bohr Hamiltonian problem that we derived with the Tietz-Hua potential, here used for describing the {\\beta}-part of the nuclear collective potential plus harmonic oscillator one for the {\\gamma}-part. Also, we proceed to a systematic comparison of the numerical results obtained with this kind of {\\beta}-potential with others which are widely used in such a framework as well as with the experiment. The calculations are carried out for energy spectra and electromagnetic transition probabilities for {\\gamma}-unstable and axially symmetric deformed nuclei. In the same frame, we show the effect of the shape flatness of the {\\beta}-potential beyond its minimum on transition rates calculations.
Analytical solutions for the Bohr Hamiltonian with the Woods-Saxon potential
Capak, M; Gonul, B; Bonatsos, Dennis
2015-01-01
Approximate analytical solutions in closed form are obtained for the 5-dimensional Bohr Hamiltonian with the Woods-Saxon potential, taking advantage of the Pekeris approximation and the exactly soluble one-dimensional extended Woods-Saxon potential with a dip near its surface. Comparison to the data for several gamma-unstable and prolate deformed nuclei indicates that the potential can describe well the ground state and gamma-1 bands of many prolate deformed nuclei corresponding to large enough "well size" and diffuseness, while it fails in describing the beta-1 bands, due to its lack of a hard core, as well as in describing gamma-unstable nuclei, because of the small "well size" and diffuseness they exhibit.
A structural theory of everything
Josephson, Brian D.
2015-01-01
In this paper it is argued that Barad's Agential Realism, an approach to quantum mechanics originating in the philosophy of Niels Bohr, can be the basis of a 'theory of everything' consistent with a proposal of Wheeler that observer-participancy is the foundation of everything. On the one hand, agential realism can be grounded in models of self-organisation such as the hypercycles of Eigen, while on the other agential realism, by virtue of the 'discursive practices' that constitute one aspect...
Introducing quantum theory a graphic guide
McEvoy, J P
2013-01-01
Quantum theory confronts us with bizarre paradoxes which contradict the logic of classical physics. At the subatomic level, one particle seems to know what the others are doing, and according to Heisenberg's "uncertainty principle", there is a limit on how accurately nature can be observed. And yet the theory is amazingly accurate and widely applied, explaining all of chemistry and most of physics. "Introducing Quantum Theory" takes us on a step-by-step tour with the key figures, including Planck, Einstein, Bohr, Heisenberg and Schrodinger. Each contributed at least one crucial concept to the theory. The puzzle of the wave-particle duality is here, along with descriptions of the two questions raised against Bohr's "Copenhagen Interpretation" - the famous "dead and alive cat" and the EPR paradox. Both remain unresolved.
Chababa, M; lahbas, A; Oulne, M
2016-01-01
A prolate {\\gamma}-rigid regime of the Bohr-Mottelson Hamiltonian within the minimal length formalism, involving an infinite square well like potential in {\\beta} collective shape variable, is developed and used to describe the spectra of a variety of vibrational-like nuclei. The effect of the minimal length on the energy spectrum and the wave function is duly investigated. Numerical calculations are performed for some nuclei revealing a qualitative agreement with the available experimental data.
The Holographic Nature of Bohr Atomic Model%波尔原子模型及其全息性
Institute of Scientific and Technical Information of China (English)
赵丽特; 王喜建; 周党培
2016-01-01
This paper shows the holographic nature of the micro world and the macro world in physics by comparing the Bohr atomic model and the movement of the planets in the solar system.%文章通过波尔原子模型和太阳系中行星运动的对比，展现物理学中微观世界和宏观世界的全息性。
On γ-rigid regime of the Bohr-Mottelson Hamiltonian in the presence of a minimal length
Chabab, M.; El Batoul, A.; Lahbas, A.; Oulne, M.
2016-07-01
A prolate γ-rigid regime of the Bohr-Mottelson Hamiltonian within the minimal length formalism, involving an infinite square well like potential in β collective shape variable, is developed and used to describe the spectra of a variety of vibrational-like nuclei. The effect of the minimal length on the energy spectrum and the wave function is duly investigated. Numerical calculations are performed for some nuclei revealing a qualitative agreement with the available experimental data.
Energy Technology Data Exchange (ETDEWEB)
Bonatsos, Dennis [Institute of Nuclear Physics, NCSR ' Demokritos' GR-15310 Aghia Paraskevi, Attiki (Greece)]. E-mail: bonat@inp.demokritos.gr; Lenis, D. [Institute of Nuclear Physics, NCSR ' Demokritos' GR-15310 Aghia Paraskevi, Attiki (Greece)]. E-mail: lenis@inp.demokritos.gr; Petrellis, D. [Institute of Nuclear Physics, NCSR ' Demokritos' GR-15310 Aghia Paraskevi, Attiki (Greece)]. E-mail: petrellis@inp.demokritos.gr; Terziev, P.A. [Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, 72 Tzarigrad Road, BG-1784 Sofia (Bulgaria)]. E-mail: terziev@inrne.bas.bg; Yigitoglu, I. [Institute of Nuclear Physics, NCSR ' Demokritos' GR-15310 Aghia Paraskevi, Attiki (Greece) and Hasan Ali Yucel Faculty of Education, Istanbul University, TR-34470 Beyazit, Istanbul (Turkey)]. E-mail: yigitoglu@istanbul.edu.tr
2005-08-11
A {gamma}-rigid solution of the Bohr Hamiltonian for {gamma}=30 deg. is derived, its ground state band being related to the second order Casimir operator of the Euclidean algebra E(4). Parameter-free (up to overall scale factors) predictions for spectra and B(E2) transition rates are in close agreement to the E(5) critical point symmetry, as well as to experimental data in the Xe region around A=130.
Bonatsos, D; Petrellis, D; Terziev, P A; Yigitoglu, I; Bonatsos, Dennis
2005-01-01
A gamma-rigid solution of the Bohr Hamiltonian for gamma = 30 degrees is derived, its ground state band being related to the second order Casimir operator of the Euclidean algebra E(4). Parameter-free (up to overall scale factors) predictions for spectra and B(E2) transition rates are in close agreement to the E(5) critical point symmetry, as well as to experimental data in the Xe region around A=130.
Okonjo, Kehinde O; Olatunde, Abimbola M; Fodeke, Adedayo A; Babalola, J Oyebamiji
2014-06-01
We have measured the affinity of the CysF9[93]β sulfhydryl group of human deoxyhemoglobin and oxyhemoglobin for 5,5'-dithiobis(2-nitrobenzoate), DTNB, between pH ≈5.6 and 9 in order to understand the basis of the reported reduction of the Bohr effect induced by chemical modification of the sulfhydryl. We analyzed the results quantitatively on the basis of published data indicating that the sulfhydryl exists in two conformations that are coupled to the transition between two tertiary structures of hemoglobin in dynamic equilibrium. Our analyses show that the ionizable groups linked to the DTNB reaction have lower pKas of ionization in deoxyhemoglobin compared to oxyhemoglobin. So these ionizable groups should make negative contributions to the Bohr effect. We identify these groups as HisNA2[2]β, HisEF1[77]β and HisH21[143]β. We provide explanations for the finding that hemoglobin, chemically modified at CysF9[93]β, has a lower Bohr effect and a higher oxygen affinity than unmodified hemoglobin.
玻尔科学思想中的整体论%Bohr's Viewpoint on Holism
Institute of Scientific and Technical Information of China (English)
赵斌
2016-01-01
为了应对挑战量子力学完备性的EPR论文，玻尔以互补性为基础，以量子态表征关系和量子现象为主要内容，提出了整体论思想，该思想是其量子力学解释的一部分，尽管存在一定的模糊性，但在还原论的科学传统下仍有其独特的历史与哲学意义。%Bohr proposed holism in his response to EPR paper, which challenged the completeness of quantum mechanics. Bohr's viewpoint on holism is part of his interpretation of quantum mechanics, and it is based on quantum state phenetic re-lationship and quantum phenomenon. There are some ambiguities in Bohr's holism, but it is of special importance to reduc-tionism which has a long history in science.
Complementarity and the Nature of Uncertainty Relations in Einstein–Bohr Recoiling Slit Experiment
Directory of Open Access Journals (Sweden)
Shogo Tanimura
2015-07-01
Full Text Available A model of the Einstein–Bohr recoiling slit experiment is formulated in a fully quantum theoretical setting. In this model, the state and dynamics of a movable wall that has two slits in it, as well as the state of a particle incoming to the two slits, are described by quantum mechanics. Using this model, we analyzed complementarity between exhibiting an interference pattern and distinguishing the particle path. Comparing the Kennard–Robertson type and the Ozawa-type uncertainty relations, we conclude that the uncertainty relation involved in the double-slit experiment is not the Ozawa-type uncertainty relation but the Kennard-type uncertainty relation of the position and the momentum of the double-slit wall. A possible experiment to test the complementarity relation is suggested. It is also argued that various phenomena which occur at the interface of a quantum system and a classical system, including distinguishability, interference, decoherence, quantum eraser, and weak value, can be understood as aspects of entanglement.Quanta 2015; 4: 1–9.
An investigation of the nature of Bohr, Root, and Haldane effects in Octopus dofleini hemocyanin.
Miller, K I; Mangum, C P
1988-01-01
1. The pH dependence of Octopus dofleini hemocyanin oxygenation is so great that below pH 7.0 the molecule does not become fully oxygenated, even in pure O2 at 1 atm pressure. However, the curves describing percent oxygenation as a function of PO2 appear to be gradually increasing in oxygen saturation, rather than leveling out at less than full saturation. Hill plots indicate that at pH 6.6 and below the molecule is stabilized in its low affinity conformation. Thus, the low saturation of this hemocyanin in air is due to the very large Bohr shift, and not to the disabling of one or more functionally distinct O2 binding sites on the native molecule. 2. Experiments in which pH was monitored continuously while oxygenation was manipulated in the presence of CO2 provide no evidence of O2 linked binding of CO2. While CO2 does influence O2 affinity independently of pH, its effect may be due to high levels of HCO3- and CO3-, rather than molecular CO2, and it may entail a lowering of the activities of the allosteric effectors Mg2+ and Ca2+. PMID:3150406
Bohr-Weisskopf effect: influence of the distributed nuclear magnetization on hfs
International Nuclear Information System (INIS)
Nuclear magnetic moments provide a sensitive test of nuclear wave functions, in particular those of neutrons, which are not readily obtainable from other nuclear data. These are taking added importance by recent proposals to study parity non-conservation (PNC) effects in alkali atoms in isotopic series. By taking ratios of the PNC effects in pairs of isotopes, uncertainties in the atomic wave functions are largely cancelled out at the cost of knowledge of the change in the neutron wave function. The Bohr-Weisskopf effect (B-W) in the hyperfine structure interaction of atoms measures the influence of the spatial distribution of the nuclear magnetization, and thereby provides an additional constraint on the determination of the neutron wave function. The added great importance of B-W in the determination of QED effects from the hfs in hydrogen-like ions of heavy elements, as measured recently at GSI, is noted. The B-W experiments require precision measurements of the hfs interactions and, independently, of the nuclear magnetic moments. A novel atomic beam magnetic resonance (ABMR) method, combining rf and laser excitation, has been developed for a systematic study and initially applied to stable isotopes. Difficulties in adapting the experiment to the ISOLDE radioactive ion beam, which have now been surmounted, are discussed. A first radioactive beam measurement for this study, the precision hfs of 126Cs, has been obtained recently. The result is 3629.515( 0.001) MHz. The ability of ABMR to determine with high precision nuclear magnetic moments in free atoms is a desideratum for the extraction of QED effects from the hfs of the hydrogen-like ions. We also point out manifestations of B-W in condensed matter and atomic physics
El pabellón Niels Bohr. Tradición Danesa y Modernidad
Directory of Open Access Journals (Sweden)
Carmen García Sánchez
2015-12-01
Full Text Available La casa de invitados de Niels Bohr fue el primer edificio del arquitecto danés Vilhelm Wohlert (1920-2007. Arraigado a la tradición danesa, representa una renovación basada en la absorción de influencias extranjeras: la arquitectura americana y la tradición japonesa. La caja de madera tiene el carácter sensible de un organismo vivo, siempre cambiante según las variaciones de luz del día o temperatura. Puertas plegables y contraventanas generan extensiones de las habitaciones. Cuando se abren, crean una prolongación del espacio interior, que se extiende a la naturaleza circundante, y se expande hacia el espacio exterior, permitiendo su movilización. Se establece una arquitectura de flujos. Protagoniza un ejemplo de la modernidad como refinamiento en la técnica de los límites y la idea de que la arquitectura no es un objeto material, sino el espacio generado en su interior. Podría ser visto como un ikebana; “el arte del espacio”, donde se produce una circulación de aire entre sus componentes; algo vivo que expresa la tercera dimensión, el equilibrio asimétrico, un interés por la materia, su textura y efecto emocional que emana. Hay armonía y equilibrio, que transmiten serenidad y belleza; un encuentro con la naturaleza; un mundo de relaciones amable al ser humano.
Directory of Open Access Journals (Sweden)
Yoshitada Sakai
Full Text Available BACKGROUND: Carbon dioxide (CO(2 therapy refers to the transcutaneous administration of CO(2 for therapeutic purposes. This effect has been explained by an increase in the pressure of O(2 in tissues known as the Bohr effect. However, there have been no reports investigating the oxygen dissociation of haemoglobin (Hb during transcutaneous application of CO(2in vivo. In this study, we investigate whether the Bohr effect is caused by transcutaneous application of CO2 in human living body. METHODS: We used a novel system for transcutaneous application of CO(2 using pure CO(2 gas, hydrogel, and a plastic adaptor. The validity of the CO(2 hydrogel was confirmed in vitro using a measuring device for transcutaneous CO(2 absorption using rat skin. Next, we measured the pH change in the human triceps surae muscle during transcutaneous application of CO(2 using phosphorus-31 magnetic resonance spectroscopy ((31P-MRS in vivo. In addition, oxy- and deoxy-Hb concentrations were measured with near-infrared spectroscopy in the human arm with occulted blood flow to investigate O2 dissociation from Hb caused by transcutaneous application of CO(2. RESULTS: The rat skin experiment showed that CO(2 hydrogel enhanced CO(2 gas permeation through the rat skin. The intracellular pH of the triceps surae muscle decreased significantly 10 min. after transcutaneous application of CO(2. The NIRS data show the oxy-Hb concentration decreased significantly 4 min. after CO(2 application, and deoxy-Hb concentration increased significantly 2 min. after CO(2 application in the CO(2-applied group compared to the control group. Oxy-Hb concentration significantly decreased while deoxy-Hb concentration significantly increased after transcutaneous CO(2 application. CONCLUSIONS: Our novel transcutaneous CO(2 application facilitated an O(2 dissociation from Hb in the human body, thus providing evidence of the Bohr effect in vivo.
Schmidt, L Ph H; Lower, J; Jahnke, T; Schößler, S; Schöffler, M S; Menssen, A; Lévêque, C; Sisourat, N; Taïeb, R; Schmidt-Böcking, H; Dörner, R
2013-09-01
We simultaneously measured the momentum transferred to a free-floating molecular double slit and the momentum change of the atom scattering from it. Our experimental results are compared to quantum mechanical and semiclassical models. The results reveal that a classical description of the slits, which was used by Einstein in his debate with Bohr, provides a surprisingly good description of the experimental results, even for a microscopic system, if momentum transfer is not ascribed to a specific pathway but shared coherently and simultaneously between both.
Indian Academy of Sciences (India)
ERMAMATOV M J; YÉPEZ-MARTÍNEZ H; SRIVASTAVA P C
2016-05-01
The band structure of the proton-odd nuclei $^{153,155}$Eu, built on Nilsson orbitals, is investigated within the framework of a recently developed extended Bohr Hamiltonian model. The relative distance between spherical orbitals is taken into account by considering single-particle energies as a parameter which changes with increasing neutron number. Energy levels of each band and$B(E2)$ values inside the ground-state band are calculated and compared with the available experimental data. Thus, more comprehensive information on the structure of deformed nuclei can be obtained by studying the rotation–vibration spectra of odd nuclei built on Nilsson single-particle orbitals.
Vayenas, Constantinos G
2012-01-01
This book shows that the strong interaction forces, which keep hadrons and nuclei together, are relativistic gravitational forces exerted between very small particles in the mass range of neutrinos. First, this book considers the problematic motion of two charged particles under the influence of electrostatic and gravitational forces only, which shows that bound states are formed by following the same semi-classical methodology used by Bohr to describe the H atom. This approach is also coupled with Newton's gravitational law and with Einstein's special relativity. The results agree with experi
International Nuclear Information System (INIS)
We consider an oscillator subjected to a sudden change in equilibrium position or in effective spring constant, or both-to a squeeze in the language of quantum optics. We analyze the probability of transition from a given initial state to a final state, in its dependence on final-state quantum number. We make use of five sources of insight: Bohr-Sommerfeld quantization via bands in phase space, area of overlap between before-squeeze band and after-squeeze band, interference in phase space, Wigner function as quantum update of B-S band and near-zone Fresnel diffraction as mockup Wigner function
Heyrovska, Raji
2007-01-01
An earlier finding that the van der waals radii are related to their de broglie wavelengths for some non-metallic elements has been extended here to show that in fact, they vary linearly with the ground state bohr radii for all the elements of groups 1a to 8 a. Similarly, the valence shell radii and the covalent radii are shown to be linearly dependent on the bohr radii. One table of data and 5 figures have been provided here showing that all the above radii are sums of two lengths, one of which is a multiple of the bohr radius and the other, a positive or negative constant for each group of elements.
International Nuclear Information System (INIS)
Recent developments and applications of an algebraic version of Bohr's collective model, known as the algebraic collective model (ACM), have shown that fully converged calculations can be performed for a large range of Hamiltonians. Examining the algebraic structure underlying the Bohr model (BM) has also clarified its relationship with the interacting boson model (IBM), with which it has related solvable limits and corresponding dynamical symmetries. In particular, the algebraic structure of the IBM is obtained as a compactification of the BM and conversely the BM is regained in various contraction limits of the IBM. In a previous paper, corresponding contractions were identified and confirmed numerically for axially-symmetric states of relatively small deformation. In this paper, we extend the comparisons to realistic deformations and compare results of the two models in the rotor-vibrator limit. These models describe rotations and vibrations about an axially symmetric prolate or oblate rotor, and rotations and vibrations of a triaxial rotor. It is determined that most of the standard results of the BM can be obtained as contraction limits of the IBM in its U(5)-SO(6) dynamical symmetries.
Heyrovska, Raji
2007-01-01
An earlier finding that the van der waals radii are related to their de broglie wavelengths for some non-metallic elements has been extended here to show that in fact, they vary linearly with the ground state bohr radii for all the elements of groups 1a to 8 a. Similarly, the valence shell radii and the covalent radii are shown to be linearly dependent on the bohr radii. One table of data and 5 figures have been provided here showing that all the above radii are sums of two lengths, one of wh...
Tkalya, E. V.; Nikolaev, A. V.
2016-07-01
Background: The search for new opportunities to investigate the low-energy level in the 229Th nucleus, which is nowadays intensively studied experimentally, has motivated us to theoretical studies of the magnetic hyperfine (MHF) structure of the 5 /2+ (0.0 eV) ground state and the low-lying 3 /2+ (7.8 eV) isomeric state in highly charged 89+229Th and 87+229Th ions. Purpose: The aim is to calculate, with the maximal precision presently achievable, the energy of levels of the hyperfine structure of the 229Th ground-state doublet in highly charged ions and the probability of radiative transitions between these levels. Methods: The distribution of the nuclear magnetization (the Bohr-Weisskopf effect) is accounted for in the framework of the collective nuclear model with Nilsson model wave functions for the unpaired neutron. Numerical calculations using precise atomic density functional theory methods, with full account of the electron self-consistent field, have been performed for the electron structure inside and outside the nuclear region. Results: The deviations of the MHF structure for the ground and isomeric states from their values in a model of a pointlike nuclear magnetic dipole are calculated. The influence of the mixing of the states with the same quantum number F on the energy of sublevels is studied. Taking into account the mixing of states, the probabilities of the transitions between the components of the MHF structure are calculated. Conclusions: Our findings are relevant for experiments with highly ionized 229Th ions in a storage ring at an accelerator facility.
The Bohr Model and the Fifth Grade: A New Standards-Based Hands-On Physics Curriculum
Brock, Jeff; Springer, Russell; Goldberg, Bennett
2004-03-01
A semester-long, standards-based, hands-on physics curriculum appropriate for the fifth grade was developed. Previously available curricula were successful in using hands-on activities to teach basic fifth-grade physics skills and concepts, but did not attempt to foster understanding of the fundamental underlying physics. We expanded the role of inquiry-based instruction to expose students to the fundamental physics behind electricity, forces, energy, light and sound. Central to the course, the Bohr model of the atom was used as a key tool both to motivate exploration of these topics as well as to develop basic conceptual understanding of fundamental ideas in quantum and electromagnetic physics. The curriculum was designed to be compatible with both district and state-mandated standards in a high-stakes test environment. This work was supported by NSF grant DGE-0231909.
Hardy-Sobolev类上的Bohr型不等式%An Inequality of Bohr Type on Hardy-Sobolev Classes
Institute of Scientific and Technical Information of China (English)
李雪华
2009-01-01
Let β>0 and Sβ:={z ∈C:|Im z|0,denote by Bσ the class of functions f which have spectra in(-2πσ,2πσ).And let B⊥σ be the class of functions f which have no spectrum in(-2πσ,2πσ).We prove an inequality of Bohr type ||f||∞,≤πγ∧σγ∞∑κ0-(-1)k(r+1) (2k+1)r sinh((2k+1)2σβ),f ∈Hr∞,β∩B⊥σ,where λ∈(0,1),∧ and ∧'are the complete eniptic integrals of the first kind for the moduli λ and λ'=(1-λ2),respectively,and λ satisfies 4∧β-π∧'= 1-σ.The constant in the above inequality is exact.
The physical principles of the quantum theory
Heisenberg, Werner
1949-01-01
The contributions of few contemporary scientists have been as far reaching in their effects as those of Nobel Laureate Werner Heisenberg. His matrix theory is one of the bases of modern quantum mechanics, while his ""uncertainty principle"" has altered our whole philosophy of science.In this classic, based on lectures delivered at the University of Chicago, Heisenberg presents a complete physical picture of quantum theory. He covers not only his own contributions, but also those of Bohr, Dirac, Bose, de Broglie, Fermi, Einstein, Pauli, Schrodinger, Somerfield, Rupp, ·Wilson, Germer, and others
Effective field theory for deformed atomic nuclei
Papenbrock, T.; Weidenmüller, H. A.
2016-05-01
We present an effective field theory (EFT) for a model-independent description of deformed atomic nuclei. In leading order this approach recovers the well-known results from the collective model by Bohr and Mottelson. When higher-order corrections are computed, the EFT accounts for finer details such as the variation of the moment of inertia with the band head and the small magnitudes of interband E2 transitions. For rotational bands with a finite spin of the band head, the EFT is equivalent to the theory of a charged particle on the sphere subject to a magnetic monopole field.
Effective field theory for deformed atomic nuclei
Papenbrock, T
2015-01-01
We present an effective field theory (EFT) for a model-independent description of deformed atomic nuclei. In leading order this approach recovers the well-known results from the collective model by Bohr and Mottelson. When higher-order corrections are computed, the EFT accounts for finer details such as the variation of the moment of inertia with the band head and the small magnitudes of interband $E2$ transitions. For rotational bands with a finite spin of the band head, the EFT is equivalent to the theory of a charged particle on the sphere subject to a magnetic monopole field.
Singh, Gurmukh
2012-01-01
The present article is primarily targeted for the advanced college/university undergraduate students of chemistry/physics education, computational physics/chemistry, and computer science. The most recent software system such as MS Visual Studio .NET version 2010 is employed to perform computer simulations for modeling Bohr's quantum theory of…
Quantising general relativity using QED theory, an overview and extension
Bell, Sarah B. M.
2004-01-01
We summarise and discuss some of our previous results, which show that Bohr's theory of the one-electron atom may be derived from the theory underpinning Quantum ElectroDynamics (QED) or vice versa, and that General Relativity may also be derived from QED theory in the classical limit, if we use Newtonian mechanics in the right frame and self-similar tesseral hierarchies. We circumvent Newton's arguments against Descartes' vortex theory to show that the inverse square law for a force combined...
How physics confronts reality Einstein was correct, but Bohr won the game
Newton, Roger G
2009-01-01
This book recalls, for nonscientific readers, the history of quantum mechanics, the main points of its interpretation, and Einstein's objections to it, together with the responses engendered by his arguments. Most popular discussions on the strange aspects of quantum mechanics ignore the fundamental fact that Einstein was correct in his insistence that the theory does not directly describe reality. While that fact does not remove the theory's counterintuitive features, it casts them in a different light.Context is provided by following the history of two central aspects of physics: the elucida
Quantum Einstein, Bohr and the great debate about the nature of reality
Kumar, Manjit
2008-01-01
For most people, quantum theory is a byword for mysterious, impenetrable science. And yet for many years it was equally baffling for scientists themselves. Manjit Kumar gives a dramatic and superbly-written history of this fundamental scientific revolution, and the divisive debate at its heart. For 60 years most physicists believed that quantum theory denied the very existence of reality itself. Yet Kumar shows how the golden age of physics ignited the greatest intellectual debate of the twentieth century. Quantum sets the science in the context of the great upheavals of the modern age. In 1
Gauge theory of collective modes
International Nuclear Information System (INIS)
The classical theory of Riemann ellipsoids is formulated naturally as a gauge theory based on a principal G-bundle P. The structure group G = SO(3) is the vorticity group and the bundle P = GL+ (3, ℝ) is the connected component of the general linear group. The base manifold is the space of positive-definite real 3 × 3 symmetric matrices, identified geometrically with the space of inertia ellipsoids. Non-holonomic constraints determine connections on the bundle. In particular, the trivial connection corresponds to rigid body motion, the natural Riemannian connection to irrotational flow and the invariant connection to the falling cat. The curvature form determines the fluid's field tensor which is an analogue of the familiar Faraday tensor. Associated G-bundles and the covariant derivative yield new quantum geometrical collective models that are a natural generalization of the Bohr model. These new geometric structures formulate the collective model as a Yang-Mills gauge theory.
Einstein's strugges with quantum theory a reappraisal
Home, Dipankar
2007-01-01
Einstein’s Struggles with Quantum Theory: A Reappraisal by Dipankar Home and Andrew Whitaker provides a detailed account of Albert Einstein’s thinking in regard to quantum physics. Until recently, most of Einstein’s views on quantum physics were dismissed and even ridiculed; some critics even suggested that Einstein was not able to grasp the complexities of the formalism of quantum theory and subtleties of the standard interpretation of this theory known as the Copenhagen interpretation put forward by Niels Bohr and his colleagues. But was that true? Modern scholarship argues otherwise, insist Drs. Home and Whitaker, who painstakingly explain the questions Einstein raised as well as offer a detailed discussion of Einstein’s position and major contributions to quantum theory, connecting them with contemporary studies on fundamental aspects of this theory. This unique book presents a mathematical as well as a non-mathematical route through the theories, controversies, and investigations, making the disc...
Two Theories Are Better Than One
Jones, Robert
2008-03-01
All knowledge is of an approximate character (B. Russell, Human Knowledge, 1948, pg 497 and 507). Our formalisms abstract, idealize, and simplify (R. L. Epstein, Propositional Logics, 2001, Ch XI and E. Bender, An Intro. to Math. Modeling, 1978, pg v and 2). Each formalism is an idealization, often times approximating in its own DIFFERENT ways, each offering somewhat different coverage of the domain. Having MULTIPLE overlaping theories of a knowledge domain is then better than having just one theory (R. Jones, APS general meeting, April 2004). Theories are not unique (T. M. Mitchell, Machine Learning, 1997, pg 65-66 and Cooper, Machine Learning, vol. 9, 1992, pg 319). In the future every field will possess multiple theories of its domain and scientific work and engineering will be performed based on the ensemble predictions of ALL of these. In some cases the theories may be quite divergent, differing greatly one from the other. This idea can be considered an extension of Bohr's notion of complementarity, ``...different experimental arrangements...described by different physical concepts...together and only together exhaust the definable information we can obtain about the object.'' (H. J. Folse, The Philosophy of Neils Bohr, 1985, pg 238)
International Nuclear Information System (INIS)
The Fisher-Shannon information and a statistical measure of complexity are calculated in position and momentum spaces for the wavefunctions of the quantum isotropic harmonic oscillator. We show that these quantities are independent of the strength of the harmonic potential. Moreover, for each level of energy, it is found that these two indicators take their minimum values on the orbitals that correspond to the classical (circular) orbits in the Bohr-like quantum image, just those with the highest orbital angular momentum
Heyrovska, R.; Narayan, S.
2005-10-01
Recently, the ground state Bohr radius (aB) of hydrogen was shown to be divided into two Golden sections, aB,p = aB/ø2 and aB,e = aB/ø at the point of electrical neutrality, where ø = 1.618 is the Golden ratio (R. Heyrovska, Molecular Physics 103: 877-882, and the literature cited therein). The origin of the difference of two energy terms in the Rydberg equation was thus shown to be in the ground state energy itself, as shown below: EH = (1/2)e2/(κaB) = (1/2)(e2/κ) [(1/aB,p - (1/aB,e)] (1). This work brings some new results that 1) a unit charge in vacuum has a magnetic moment, 2) (e2/2κ) in eq. (1) is an electromagnetic condenser constant, 3) the de Broglie wavelengths of the proton and electron correspond to the Golden arcs of a circle with the Bohr radius, 4) the fine structure constant (α) is the ratio of the Planck's constants without and with the interaction of light with matter, 5) the g-factors of the electron and proton, ge/2 and gp/2 divide the Bohr radius at the magnetic center and 6) the ``mysterious'' value (137.036) of α -1 = (360/ø2) - (2/ø3), where (2/ø3) arises from the difference, (gp - ge).
Kovalevsky, Andrey Y; Chatake, Toshiyuki; Shibayama, Naoya; Park, Sam-Yong; Ishikawa, Takuya; Mustyakimov, Marat; Fisher, Zoe; Langan, Paul; Morimoto, Yukio
2010-04-30
We have investigated the protonation states of histidine residues (potential Bohr groups) in the deoxy form (T state) of human hemoglobin by direct determination of hydrogen (deuterium) positions with the neutron protein crystallography technique. The reversible binding of protons is key to the allosteric regulation of human hemoglobin. The protonation states of 35 of the 38 His residues were directly determined from neutron scattering omit maps, with 3 of the remaining residues being disordered. Protonation states of 5 equivalent His residues--alpha His20, alpha His50, alpha His89, beta His143, and beta His146--differ between the symmetry-related globin subunits. The distal His residues, alpha His58 and beta His63, are protonated in the alpha 1 beta 1 heterodimer and are neutral in alpha 2 beta 2. Buried residue alpha His103 is found to be protonated in both subunits. These distal and buried residues have the potential to act as Bohr groups. The observed protonation states of His residues are compared to changes in their pK(a) values during the transition from the T to the R state and the results provide some new insights into our understanding of the molecular mechanism of the Bohr effect.
Non-Locality Versus Locality:. the Epistemological Background of the Einstein Bohr Debate
Borzeszkowski, Horst-Heino V.; Wahsner, Renate
2000-08-01
In its core, the non-locality-locality debate is a discussion about the concept of the physical reality. The difference between the measurement bases of classical and quantum mechanics is often interpreted as a loss of reality arising in quantum mechanics. In this paper it is shown that this apparent loss occurs only if one believes that everyday experience determines the Euclidean space, instead of considering this space, both in classical and quantum mechanics, as a theoretical construction needed for measurement and representing one part of a dualistic space conception. From this point of view, Einstein's program of a unified field theory can be interpreted as the attempt to find a physical theory that is less dualistic. However, if one regards this dualism as resulting from the requirements of measurements, one can hope for a weakening of the dualism but not expect to remove it completely. Further, it follows from the requirements of measurements that the Heisenberg cut cannot be arbitrarily far moved towards the observer. Epistemological discussions on quantum mechanics yield two insights: (i) To acquire physical knowledge, means of cognition are always necessary, and measurement provides this means. (ii) The space of measurement and the space of the representation of physical dynamics must be distinguished conceptually; both coincide factually in classical physics, but not so in quantum mechanics.
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
Jensen, F B
2004-11-01
The discovery of the S-shaped O2 equilibrium curve and the Bohr effect in 1904 stimulated a fertile and continued research into respiratory functions of blood and allosteric mechanisms in haemoglobin (Hb). The Bohr effect (influence of pH/CO2 on Hb O2 affinity) and the reciprocal Haldane effect (influence of HbO2 saturation on H+/CO2 binding) originate in the Hb oxy-deoxy conformational change and allosteric interactions between O2 and H+/CO2 binding sites. In steady state, H+ is passively distributed across the vertebrate red blood cell (RBC) membrane, and intracellular pH (pHi) changes are related to changes in extracellular pH, Hb-O2 saturation and RBC organic phosphate content. As the Hb molecule shifts between the oxy and deoxy conformation in arterial-venous gas transport, it delivers O2 and takes up CO2 and H+ in tissue capillaries (elegantly aided by the Bohr effect). Concomitantly, the RBC may sense local O2 demand via the degree of Hb deoxygenation and release vasodilatory agents to match local blood flow with requirements. Three recent hypotheses suggest (1) release of NO from S-nitroso-Hb upon deoxygenation, (2) reduction of nitrite to vasoactive NO by deoxy haems, and (3) release of ATP. Inside RBCs, carbonic anhydrase (CA) provides fast hydration of metabolic CO2 and ensures that the Bohr shift occurs during capillary transit. The formed H+ is bound to Hb (Haldane effect) while HCO3- is shifted to plasma via the anion exchanger (AE1). The magnitude of the oxylabile H+ binding shows characteristic differences among vertebrates. Alternative strategies for CO2 transport include direct HCO3- binding to deoxyHb in crocodilians, and high intracellular free [HCO3-] (due to high pHi) in lampreys. At the RBC membrane, CA, AE1 and other proteins may associate into what appears to be an integrated gas exchange metabolon. Oxygenation-linked binding of Hb to the membrane may regulate glycolysis in mammals and perhaps also oxygen-sensitive ion transport involved in
Effective field theory for deformed atomic nuclei
Papenbrock, T.; Weidenmüller, H. A.
2015-01-01
We present an effective field theory (EFT) for a model-independent description of deformed atomic nuclei. In leading order this approach recovers the well-known results from the collective model by Bohr and Mottelson. When higher-order corrections are computed, the EFT accounts for finer details such as the variation of the moment of inertia with the band head and the small magnitudes of interband $E2$ transitions. For rotational bands with a finite spin of the band head, the EFT is equivalen...
Rao, M J; Acharya, A S
1992-08-18
Glu-43(beta) of hemoglobin A exhibits a high degree of chemical reactivity around neutral pH for amidation with nucleophiles in the presence of carbodiimide. Such a reactivity is unusual for the side-chain carboxyl groups of proteins. In addition, the reactivity of Glu-43(beta) is also sensitive to the ligation state of the protein [Rao, M. J., & Acharya, A. S. (1991) J. Protein Chem. 10, 129-138]. The influence of deoxygenation of hemoglobin A on the chemical reactivity of the gamma-carboxyl group of Glu-43(beta) has now been investigated as a function of pH (from 5.5 to 7.5). The chemical reactivity of Glu-43(beta) for amidation increases upon deoxygenation only when the modification reaction is carried out above pH 6.0. The pH-chemical reactivity profile of the amidation of hemoglobin A in the deoxy conformation reflects an apparent pKa of 7.0 for the gamma-carboxyl group of Glu-43(beta). This pKa is considerably higher than the pKa of 6.35 for the oxy conformation. The deoxy conformational transition mediated increase in the pKa of the gamma-carboxyl group of Glu-43(beta) implicates this carboxyl group as an alkaline Bohr group. The amidated derivative of hemoglobin A with 2 mol of glycine ethyl ester covalently bound to the protein was isolated by CM-cellulose chromatography.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1354984
Unified description of structure and reactions: implementing the Nuclear Field Theory program
Broglia, Ricardo A; Barranco, Francisco; Vigezzi, Enrico; Idini, Andrea; Potel, Gregory
2015-01-01
The modern theory of the atomic nucleus results from the merging of the liquid drop (Niels Bohr and Fritz Kalckar) and of the shell model (Marie Goeppert Meyer and Axel Jensen), which contributed the concepts of collective excitations and of independent-particle motion respectively. The unification of these apparently contradictory views in terms of the particle-vibration (rotation) coupling (Aage Bohr and Ben Mottelson) has allowed for an ever increasingly complete, accurate and detailed description of the nuclear structure, Nuclear Field Theory (NFT, developed by the Copenhagen-Buenos Aires collaboration) providing a powerful quantal embodiment. In keeping with the fact that reactions are not only at the basis of quantum mechanics (statistical interpretation, Max Born) , but also the specific tools to probe the atomic nucleus, NFT is being extended to deal with processes which involve the continuum in an intrinsic fashion, so as to be able to treat them on an equal footing with those associated with discret...
Supersymmetric Gauge Theories with Matters, Toric Geometries and Random Partitions
Noma, Y
2006-01-01
We derive the relation between the Hilbert space of certain geometries under the Bohr-Sommerfeld quantization and the perturbative prepotentials for the supersymmetric five-dimensional SU(N) gauge theories with massive fundamental matters and with one massive adjoint matter. The gauge theory with one adjoint matter shows interesting features. A five-dimensional generalization of Nekrasov's partition function can be written as a correlation function of two-dimensional chiral bosons and as a partition function of a statistical model of partitions. From a ground state of the statistical model we reproduce the polyhedron which characterizes the Hilbert space.
Sobhani, Hadi; Hassanabadi, Hassan
2016-08-01
This paper contains study of Bohr Hamiltonian considering time-dependent form of two important and famous nuclear potentials and harmonic oscillator. Dependence on time in interactions is considered in general form. In order to investigate this system, a powerful mathematical method has been employed, so-called Lewis-Riesenfeld dynamical invariant method. Appropriate dynamical invariant for considered system has been constructed. Then its eigen functions and the wave function are derived. At the end, we discussed about physical meaning of the results.
尼尔斯·玻尔与中国传统文化%Niels Bohr and the Traditional Culture of China
Institute of Scientific and Technical Information of China (English)
方华基
2005-01-01
@@ 1尼尔斯·玻尔 尼尔斯·玻尔(Niles Bohr 1885～1962)是丹麦物理学家.他不但在学术上是一位伟大的开拓者,而且还是科学力量的组织者和领导者.1922年,由于在"研究原子结构和由此产生的辐射所做出的贡献",玻尔荣获诺贝尔物理学奖.
Shi, Yu
2015-01-01
2015 is the International Year of Light and Light-based Technologies (IYL), while the physics and chemistry Nobel Prizes 2014 are both about light. The work leading to the two prizes share the same basic theoretical foundation: when an electron jumps from a higher energy level to a lower energy level, the energy difference is transformed into a photon. This basic way of light generation is a key part of the Old Quantum Theory. Interestingly, the date of announcing the 2014 Nobel Prize for physics coincided with the birthdays of Niels Bohr and, especially, of Planck's blackbody radiation formula. In connection with the two 2014 Nobel Prizes, we recall the development of the Old Quantum Theory by Planck, Einstein and Bohr.
Quadrupole shape dynamics in view from a theory of large amplitude collective motion
Matsuo, M; Sato, K; Matsuyanagi, K; Nakatsukasa, T; Yoshida, K
2014-01-01
Low-lying quadrupole shape dynamics is a typical manifestation of large amplitude collective motion in finite nuclei. To describe the dynamics on a microscopic foundation, we have formulated a consistent scheme in which the Bohr collective Hamiltonian for the five dimensional quadrupole shape variables is derived on the basis of the time-dependent Hartree-Fock-Bogoliubov theory. It enables us to incorporates the Thouless-Valatin effect on the shape inertial functions, which has been neglected in previous microscopic Bohr Hamiltonian approaches. Quantitative successes are illustrated for the low-lying spectra in $^{68}$Se, $^{30-34}$Mg and $^{58-64}$Cr, which display shape-coexistence, -mixing and -transitional behaviors.
Schrödinger spectra and the effective Hamiltonian of weak KAM theory on the flat torus
Zanelli, Lorenzo
2016-08-01
In this paper we investigate the link between the spectrum of some periodic Schrödinger type operators and the effective Hamiltonian of the weak KAM theory. We show that the extension of some local quasimodes is linked to the localization of the Schrödinger spectrum. Such a result provides additional information with respect to the well known Bohr-Sommerfeld quantization rules, here in a more general setting than the integrable or quasi-integrable ones.
Tkalya, E V
2016-01-01
The magnetic hyperfine (MHF) structure of the $5/2^+$(0.0 eV) ground state and the low-lying $3/2^+$(7.8 eV) isomeric state of the $^{229}$Th nucleus in highly charged ions Th$^{89+}$ and Th$^{87+}$ is calculated. The distribution of the nuclear magnetization (the Bohr-Weisskopf effect) is accounted for in the framework of the collective nuclear model with the wave functions of the Nilsson model for the unpaired neutron. The deviations of the MHF structure for the ground and isomeric states from their values in the model of point-like nuclear magnetic dipole are calculated. The influence of the mixing of the states with the same quantum number $F$ on the energy of sublevels is studied. Taking into account the mixing of states, the probabilities of the transitions between the components of MHF structure are found.
Kaloyerou, P. N.
2016-02-01
I argue that quantum optical experiments that purport to refute Bohr's principle of complementarity (BPC) fail in their aim. Some of these experiments try to refute complementarity by refuting the so called particle-wave duality relations, which evolved from the Wootters-Zurek reformulation of BPC (WZPC). I therefore consider it important for my forgoing arguments to first recall the essential tenets of BPC, and to clearly separate BPC from WZPC, which I will argue is a direct contradiction of BPC. This leads to a need to consider the meaning of particle-wave duality relations and to question their fundamental status. I further argue (albeit, in opposition to BPC) that particle and wave complementary concepts are on a different footing than other pairs of complementary concepts.
Rise and fall of the old quantum theory
Bucher, Manfred
2008-01-01
The old quantum theory of Bohr and Sommerfeld was abandonned for the wrong reason. Its contradictions were caused not by the orbit concept but by a mental barrier--the inconceivability that an electron might collide with the atomic nucleus. Removing that barrier resolves the theory's main failures--incorrect orbital momenta, He atom, H2+ molecule ion. The inclusion of electron oscillations through the nucleus--a concept called "Coulomb oscillator"--renders the old quantum theory consistent with quantum mechanics (although devoid of wave character). The triple success of the Bohr-Sommerfeld model is its correct description of the H atom (and one-electron ions) concerning (1) the energy levels Enl, (2) the orbital angular momenta Lnl--if corrected as Lnl^2 = l(l+1) hbar^2 and with the Coulomb oscillator included--and (3) the orbits' space quantization--with (Lnl)z = ml hbar. These achievements are succinctly represented by the principal, angular and magnetic quantum numbers (n, l, ml) and visualized by orbital ...
Energy Technology Data Exchange (ETDEWEB)
Jaehnert, Martin [MPIWG, Berlin (Germany)
2013-07-01
In 1922 Niels Bohr wrote a letter to Arnold Sommerfeld complaining that: ''[i]n the last years my attempts to develop the principles of quantum theory were met with very little understanding.'' Looking for the correspondence idea in publications, one finds that the principle was indeed hardly applied by physicists outside of Copenhagen. Only by 1922 physicists from wider research networks of quantum theory started to transfer the principle into their research fields, often far removed from its initial realm of atomic spectroscopy. How and why did physicists suddenly become interested in the idea that Bohr*s writings had been promoting since 1918? How was the correspondence principle transferred to these fields and how did its transfer affect these fields and likewise the correspondence principle itself? To discuss these questions, my talk focuses on the work of James Franck and Friedrich Hund on the Ramsauer effect in 1922 and follows the interrelation of the developing understanding of a newly found effect and the adaptation of the correspondence idea in a new conceptual and sociological context.
Dajnowicz, Steven; Seaver, Sean; Hanson, B Leif; Fisher, S Zoë; Langan, Paul; Kovalevsky, Andrey Y; Mueser, Timothy C
2016-07-01
Neutron crystallography provides direct visual evidence of the atomic positions of deuterium-exchanged H atoms, enabling the accurate determination of the protonation/deuteration state of hydrated biomolecules. Comparison of two neutron structures of hemoglobins, human deoxyhemoglobin (T state) and equine cyanomethemoglobin (R state), offers a direct observation of histidine residues that are likely to contribute to the Bohr effect. Previous studies have shown that the T-state N-terminal and C-terminal salt bridges appear to have a partial instead of a primary overall contribution. Four conserved histidine residues [αHis72(EF1), αHis103(G10), αHis89(FG1), αHis112(G19) and βHis97(FG4)] can become protonated/deuterated from the R to the T state, while two histidine residues [αHis20(B1) and βHis117(G19)] can lose a proton/deuteron. αHis103(G10), located in the α1:β1 dimer interface, appears to be a Bohr group that undergoes structural changes: in the R state it is singly protonated/deuterated and hydrogen-bonded through a water network to βAsn108(G10) and in the T state it is doubly protonated/deuterated with the network uncoupled. The very long-term H/D exchange of the amide protons identifies regions that are accessible to exchange as well as regions that are impermeable to exchange. The liganded relaxed state (R state) has comparable levels of exchange (17.1% non-exchanged) compared with the deoxy tense state (T state; 11.8% non-exchanged). Interestingly, the regions of non-exchanged protons shift from the tetramer interfaces in the T-state interface (α1:β2 and α2:β1) to the cores of the individual monomers and to the dimer interfaces (α1:β1 and α2:β2) in the R state. The comparison of regions of stability in the two states allows a visualization of the conservation of fold energy necessary for ligand binding and release. PMID:27377386
Dajnowicz, Steven; Seaver, Sean; Hanson, B Leif; Fisher, S Zoë; Langan, Paul; Kovalevsky, Andrey Y; Mueser, Timothy C
2016-07-01
Neutron crystallography provides direct visual evidence of the atomic positions of deuterium-exchanged H atoms, enabling the accurate determination of the protonation/deuteration state of hydrated biomolecules. Comparison of two neutron structures of hemoglobins, human deoxyhemoglobin (T state) and equine cyanomethemoglobin (R state), offers a direct observation of histidine residues that are likely to contribute to the Bohr effect. Previous studies have shown that the T-state N-terminal and C-terminal salt bridges appear to have a partial instead of a primary overall contribution. Four conserved histidine residues [αHis72(EF1), αHis103(G10), αHis89(FG1), αHis112(G19) and βHis97(FG4)] can become protonated/deuterated from the R to the T state, while two histidine residues [αHis20(B1) and βHis117(G19)] can lose a proton/deuteron. αHis103(G10), located in the α1:β1 dimer interface, appears to be a Bohr group that undergoes structural changes: in the R state it is singly protonated/deuterated and hydrogen-bonded through a water network to βAsn108(G10) and in the T state it is doubly protonated/deuterated with the network uncoupled. The very long-term H/D exchange of the amide protons identifies regions that are accessible to exchange as well as regions that are impermeable to exchange. The liganded relaxed state (R state) has comparable levels of exchange (17.1% non-exchanged) compared with the deoxy tense state (T state; 11.8% non-exchanged). Interestingly, the regions of non-exchanged protons shift from the tetramer interfaces in the T-state interface (α1:β2 and α2:β1) to the cores of the individual monomers and to the dimer interfaces (α1:β1 and α2:β2) in the R state. The comparison of regions of stability in the two states allows a visualization of the conservation of fold energy necessary for ligand binding and release.
Boundary Liouville Theory: Hamiltonian Description and Quantization
Directory of Open Access Journals (Sweden)
Harald Dorn
2007-01-01
Full Text Available The paper is devoted to the Hamiltonian treatment of classical and quantum properties of Liouville field theory on a timelike strip in 2d Minkowski space. We give a complete description of classical solutions regular in the interior of the strip and obeying constant conformally invariant conditions on both boundaries. Depending on the values of the two boundary parameters these solutions may have different monodromy properties and are related to bound or scattering states. By Bohr-Sommerfeld quantization we find the quasiclassical discrete energy spectrum for the bound states in agreement with the corresponding limit of spectral data obtained previously by conformal bootstrap methods in Euclidean space. The full quantum version of the special vertex operator $e^varphi$ in terms of free field exponentials is constructed in the hyperbolic sector.
Heyrovska, R.; Narayan, S
2005-01-01
Sommerfeld introduced the fine-structure constant into physics, while he was taking into account the relativistic effects in the theory of the hydrogen atom. Ever since, it has puzzled many scientists like Eddington, Dirac, Feynman and others. Here the mysterious fine-structure constant, alpha = (Compton wavelength/de Broglie wavelength) = 1/137.036 = 2.627/360 is interpreted based on the finding that it is close to 2.618/360 = 1/137.508, where the Compton wavelength for hydrogen is a distanc...
唐古特白刺果实提取物抗氧化活性评价%Antioxidant Activity of Extracts from Nitraria tangutorum Bohr.Fruits
Institute of Scientific and Technical Information of China (English)
任旭; 陈贵林
2011-01-01
采用95%乙醇加热回流提取唐古特白刺(Nitraria tangutorum Bohr.)果实成分,依次用石油醚、氯仿、乙酸乙酯和正丁醇进行萃取.用DPPH自由基法和ABTS+·法进行抗氧化活性实验,并选取抗坏血酸(VC)和生育酚(VE)作为对照.结果显示乙酸乙酯提取物(EAF)具有较高的抗氧化性,进一步对其进行硅胶柱层析分离,得到6个组分(EAF-Ⅰ～EAF-Ⅵ),其中EAF-Ⅰ和EAF-Ⅳ的抗氧化性均高于VC和VE.白刺果实提取物具有良好的抗氧化性,有进一步开发为天然抗氧化剂的应用前景.
Entropy Spectrum of Black Holes of Heterotic String Theory via Adiabatic Invariance
Institute of Scientific and Technical Information of China (English)
Alexis Larra？ aga; Luis Cabarique; Manuel Londo？ o
2012-01-01
Using adiabatic invariance and the Bohr-Sommerfeld quantization rule we investigate the entropy spectroscopy of two black holes of heterotic string theory,the charged GMGHS and the rotating Sen solutions.It is shown that the entropy spectrum is equally spaced in both cases,identically to the spectrum obtained before for Schwarzschild,Reissner-Nordstr?m and Kerr black holes.Since the adiabatic invariance method does not use quasinormal mode analysis,there is no need to impose the small charge or small angular momentum limits and there is no confusion on whether the real part or the imaginary part of the modes is responsible for the entropy spectrum.
Institute of Scientific and Technical Information of China (English)
袁立新
2012-01-01
用玻尔原子模型轨道能量与光子能量比的方式,对精细结构常数值的求解作了论证；对以玻尔原子模型轨道速度V与光速c比的精细结构常数值求解,与玻尔原子模型轨道能量与光子能量比的同值性作了分析；并论证了由速度比定义的精细结构常数,是一般式玻尔原子模型轨道能量与光子能量比的特解.%The fine structure constant has been analysed by the ratio of the Bohr atom model energy to photon energy. That the phenomenon of same value of the ratio of the Bohr atom model energy to photon energy and the ratio of the velocity v of the the Bohr atom model to the velocity c has been analysed. That the fine structure constant is given by the ratio of the velocity v of the the Bohr atom model to velocity c is a characteristic solution from the general formula of the ratio of the Bohr atom model energy to photon energy.
DEFF Research Database (Denmark)
Wæver, Ole
2009-01-01
Kenneth N. Waltz's 1979 book, Theory of International Politics, is the most influential in the history of the discipline. It worked its effects to a large extent through raising the bar for what counted as theoretical work, in effect reshaping not only realism but rivals like liberalism...... and reflectivism. Yet, ironically, there has been little attention to Waltz's very explicit and original arguments about the nature of theory. This article explores and explicates Waltz's theory of theory. Central attention is paid to his definition of theory as ‘a picture, mentally formed' and to the radical anti......-empiricism and anti-positivism of his position. Followers and critics alike have treated Waltzian neorealism as if it was at bottom a formal proposition about cause-effect relations. The extreme case of Waltz being so victorious in the discipline, and yet being consistently mis-interpreted on the question of theory...
Unified description of structure and reactions: implementing the nuclear field theory program
Broglia, R. A.; Bortignon, P. F.; Barranco, F.; Vigezzi, E.; Idini, A.; Potel, G.
2016-06-01
The modern theory of the atomic nucleus results from the merging of the liquid drop model of Niels Bohr and Fritz Kalckar, and of the shell model of Marie Goeppert Meyer and Hans Jensen. The first model contributed the concepts of collective excitations. The second, those of independent-particle motion. The unification of these apparently contradictory views in terms of the particle-vibration and particle-rotation couplings carried out by Aage Bohr and Ben Mottelson has allowed for an ever more complete, accurate and detailed description of nuclear structure. Nuclear field theory (NFT), developed by the Copenhagen-Buenos Aires collaboration, provided a powerful quantal embodiment of this unification. Reactions are not only at the basis of quantum mechanics (statistical interpretation, Max Born), but also the specific tools to probe the atomic nucleus. It is then natural that NFT is being extended to deal with processes which involve the continuum in an intrinsic fashion, so as to be able to treat them on an equal footing with those associated with bound states (structure). As a result, spectroscopic studies of transfer to continuum states could eventually make use of the NFT rules, properly extended to take care of recoil effects. In the present contribution we review the implementation of the NFT program of structure and reactions, setting special emphasis on open problems and outstanding predictions.
A Uniﬁed Theory of Interaction: Gravitation and Electrodynamics
Directory of Open Access Journals (Sweden)
Wagener P.
2008-10-01
Full Text Available A theory is proposed from which the basic equations of gravitation and electromagnetism are derived from a single Lagrangian. The total energy of an atom can be expressed in a power series of the fine structure constant, $alpha$. Specific selections of these terms yield the relativistic correction to the Bohr values of the hydrogen spectrum and the Sommerfeld-Dirac equation for the fine structure spectrum of the hydrogen atom. Expressions for the classical electron radius and some of the Large Number Coincidences are derived. A Lorentz-type force equation is derived for both gravitation and electrodynamics. Electron spin is shown to be an effect of fourth order in $alpha$.
Husi C.
2007-01-01
The historic Proton Synchrotron (PS) control room is about to start a new life. Opened by Niels Bohr in 1960, the room will be reused by CMS to built its control centre. When finished, it will resemble the CERN Control Centre for LHC operations, located in Prevessin.
Foundations of quantum theory and thermodynamics
International Nuclear Information System (INIS)
Physical reasons to support the statement that Quantum theory (Quantum Gravity in particular as well as Classical Gravity) loose applicability due to Thermodynamical effects are presented. The statement is based on several points: 1. N.Bohr requirement that measuring units must have macro size is one of common fundamentals of Quantum theory. 2. The Reference System--the base notion of Classical and Quantum theory and of any observation process as well, must be protected from any external Thermal influence to provide precise measurements of Time and Distance. 3. No physical screen or process, that can reduce or reflect the action of Gravity is known and hence nothing can cool or protect the measuring units of the Reference System from heating by Thermal Gravity fluctuations. 4. Thermal Gravity fluctuations--Thermal fluctuations of Gravity free fall acceleration, are induced by Thermal behavior of matter and Thermal properties of Electromagnetic fields, but usually are neglected as near zero values. Matter heat Gravity and Gravity heat Matter. Thermal fluctuations of Gravity free fall acceleration act as a Universal Heater on any kind of Matter or Field. 5. Nevertheless the usual Thermal properties of Gravity are negligible, they can be dramatically increased by Gravity Blue Shift (near Gravitational Radius) or usual Doppler effects. 6. If Thermal action of Gravity become significant all measurements of Time and Distance that determine the Reference System notion, must depend on the Thermal properties of Gravity, like Temperature or Entropy, and that violate applicability of the Reference System notion and Quantum and Classical theories as well. If so, Thermal notions, like Temperature or Entropy, become more fundamental than common Time and Distance characters. The definition of the Temperature of the Gravity fluctuations and it's possible measurements are suggested
Nekrasov, Nikita
2004-01-01
We present the evidence for the existence of the topological string analogue of M-theory, which we call Z-theory. The corners of Z-theory moduli space correspond to the Donaldson-Thomas theory, Kodaira-Spencer theory, Gromov-Witten theory, and Donaldson-Witten theory. We discuss the relations of Z-theory with Hitchin's gravities in six and seven dimensions, and make our own proposal, involving spinor generalization of Chern-Simons theory of three-forms. Based on the talk at Strings'04 in Paris.
Black Holes - a Simplified Theory for Quantum Gravity Non-Specialists
Pankovic, Vladan
2009-01-01
In this work we present a simplified description and calculation of the Kerr-Newman black hole basic dynamical (horizons) and thermo-dynamical (Bekenstein-Hawking entropy, Bekenstein entropy/surface quantization, Hawking temperature and radiation) characteristics. Also, a possibility of the fission of nearly extremal black hole is considered in full analogy with remarkable, simple Bohr-Wheeler theory of the nuclear fission. Given black is physically based on the well-known principles of the classical physics (mechanics, thermodynamics and electro-dynamics). It includes the non-relativistic quantum mechanics and statistical mechanics too. Finally, it includes the elementary form of the general relativistic equivalence principle only. Also, suggested simplified description includes mathematically, practically, only simple algebraic equations. Here many steps are extremely simplified and formal, representing, in fact, a linear approximation of the quantum gravity theories (black hole entropy and temperature can ...
Quantum theory and the flight from realism philosophical responses to quantum mechanics
Norris, Christopher
2002-01-01
This book is a critical introduction to the long-standing debate concerning the conceptual foundations of quantum mechanics and the problems it has posed for physicists and philosophers from Einstein to the present. Quantum theory has been a major infulence on postmodernism, and presents significant problems for realists. Keeping his own realist position in check, Christopher Norris subjects a wide range of key opponents and supporters of realism to a high and equal level of scrutiny. With a characteristic combination of rigour and intellectual generosity, he draws out the merits and weaknesses from opposing arguments. In a sequence of closely argued chapters, Norris examines the premises of orthodox quantum theory, as developed most influentially by Bohr and Heisenberg, and its impact on varous philosophical developments. These include the ideas developed by W.V Quine, Thomas Kuhn, Michael Dummett, Bas van Fraassen, and Hilary Puttnam. In each case, Norris argues, these thinkers have been influenced by the...
Theory of superfluidity macroscopic quantum waves
International Nuclear Information System (INIS)
A new description of superfluidity is proposed, based upon the fact that Bogoliubov's theory of superfluidity exhibits some so far unsuspected macroscopic quantum waves (MQWs), which have a topological nature and travel within the fluid at subsonic velocities. To quantize the bounded quasi-particles the field theoretic version of the Bohr-Sommerfeld quantization rule, is employed and also resort to a variational computation. In an instantaneous configuration the MQWs cut the condensate into blocks of phase, providing, by analogy with ferromagnetism, a nice explanation of what could be the lambda-transition. A crude estimate of the critical temperature gives T sub(c) approximately equal to 2-4K. An attempt is made to understand Tisza's two-fluid model in terms of the MQWs, and we rise the conjecture that they play an important role in the motion of second. We present also a qualitative prediction concerning to the behavior of the 'phononroton' peak below 1.0K, and propose two experiments to look for MQWs
Marino Beiras, Marcos
2001-01-01
We give an overview of the relations between matrix models and string theory, focusing on topological string theory and the Dijkgraaf--Vafa correspondence. We discuss applications of this correspondence and its generalizations to supersymmetric gauge theory, enumerative geometry and mirror symmetry. We also present a brief overview of matrix quantum mechanical models in superstring theory.
Jara, Pascual; Torrecillas, Blas
1988-01-01
The papers in this proceedings volume are selected research papers in different areas of ring theory, including graded rings, differential operator rings, K-theory of noetherian rings, torsion theory, regular rings, cohomology of algebras, local cohomology of noncommutative rings. The book will be important for mathematicians active in research in ring theory.
Gearhart, Clayton A.
2014-09-01
In 1911, James Franck and Gustav Hertz began a collaboration to investigate the nature of collisions of slow electrons with gas molecules that led to a series of carefully planned and executed experiments, culminating in their discovery of inelastic collisions of electrons with mercury vapor atoms in 1914. This paper tells the story of their collaboration and the eventual reinterpretation of their results as a confirmation of Niels Bohr's new atomic theory, largely as a result of experiments done in North America during the Great War.
Gearhart, Clayton A.
2014-09-01
In 1911, James Franck and Gustav Hertz began a collaboration to investigate the nature of collisions of slow electrons with gas molecules that led to a series of carefully planned and executed experiments, culminating in their discovery of inelastic collisions of electrons with mercury vapor atoms in 1914. This paper tells the story of their collaboration and the eventual reinterpretation of their results as a confirmation of Niels Bohr's new atomic theory, largely as a result of experiments done in North America during the Great War.
International Nuclear Information System (INIS)
Of all supergravity theories, the maximal, i.e., N = 8 in 4-dimension or N = 1 in 11-dimension, theory should perform the unification since it owns the highest degree of symmetry. As to the N = 1 in d = 11 theory, it has been investigated how to compactify to the d = 4 theories. From the phenomenological point of view, local SUSY GUTs, i.e., N = 1 SUSY GUTs with soft breaking terms, have been studied from various angles. The structures of extended supergravity theories are less understood than those of N = 1 supergravity theories, and matter couplings in N = 2 extended supergravity theories are under investigation. The harmonic superspace was recently proposed which may be useful to investigate the quantum effects of extended supersymmetry and supergravity theories. As to the so-called Kaluza-Klein supergravity, there is another possibility. (Mori, K.)
Miller, William H.; Cotton, Stephen J.
2016-08-01
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.
DEFF Research Database (Denmark)
Linder, Stefan; Foss, Nicolai Juul
2015-01-01
Agency theory studies the problems and solutions linked to delegation of tasks from principals to agents in the context of conflicting interests between the parties. Beginning from clear assumptions about rationality, contracting, and informational conditions, the theory addresses problems of ex...... agency theory to enjoy considerable scientific impact on social science; however, it has also attracted considerable criticism....
DEFF Research Database (Denmark)
Linder, Stefan; Foss, Nicolai Juul
Agency theory studies the problems and solutions linked to delegation of tasks from principals to agents in the context of conflicting interests between the parties. Beginning from clear assumptions about rationality, contracting and informational conditions, the theory addresses problems of ex...... agency theory to enjoy considerable scientific impact on social science; however, it has also attracted considerable criticism....
Williams, Jeffrey
1994-01-01
Considers the recent flood of anthologies of literary criticism and theory as exemplifications of the confluence of pedagogical concerns, economics of publishing, and other historical factors. Looks specifically at how these anthologies present theory. Cites problems with their formatting theory and proposes alternative ways of organizing theory…
Blanchard, Philippe; Hellmich, Mario; Ługiewicz, Piotr; Olkiewicz, Robert
Quantum mechanics is the greatest revision of our conception of the character of the physical world since Newton. Consequently, David Hilbert was very interested in quantum mechanics. He and John von Neumann discussed it frequently during von Neumann's residence in Göttingen. He published in 1932 his book Mathematical Foundations of Quantum Mechanics. In Hilbert's opinion it was the first exposition of quantum mechanics in a mathematically rigorous way. The pioneers of quantum mechanics, Heisenberg and Dirac, neither had use for rigorous mathematics nor much interest in it. Conceptually, quantum theory as developed by Bohr and Heisenberg is based on the positivism of Mach as it describes only observable quantities. It first emerged as a result of experimental data in the form of statistical observations of quantum noise, the basic concept of quantum probability.
Harris, Tina
2015-04-29
Grounded theory is a popular research approach in health care and the social sciences. This article provides a description of grounded theory methodology and its key components, using examples from published studies to demonstrate practical application. It aims to demystify grounded theory for novice nurse researchers, by explaining what it is, when to use it, why they would want to use it and how to use it. It should enable nurse researchers to decide if grounded theory is an appropriate approach for their research, and to determine the quality of any grounded theory research they read.
Rowen, Louis H
1991-01-01
This is an abridged edition of the author's previous two-volume work, Ring Theory, which concentrates on essential material for a general ring theory course while ommitting much of the material intended for ring theory specialists. It has been praised by reviewers:**""As a textbook for graduate students, Ring Theory joins the best....The experts will find several attractive and pleasant features in Ring Theory. The most noteworthy is the inclusion, usually in supplements and appendices, of many useful constructions which are hard to locate outside of the original sources....The audience of non
原子物理学发展中的一座里程碑--玻尔理论%A milestone in the development of atomic physics--Bohr theory
Institute of Scientific and Technical Information of China (English)
王印磊; 李卫平
2005-01-01
概括了自十九世纪以来经典物理学所取得的重大成就,并回顾了玻尔理论的建立背景,阐述了玻尔理论的基本原理.介绍了经典物理理论所不能解决的诸多物理现象,玻尔解释原子结构的稳定性和原子光谱规律的新理论,总结性的分析了玻尔理论的历史地位和它的相对局限性.
Institute of Scientific and Technical Information of China (English)
范岱年
2012-01-01
中国早在20世纪20年代初就开始介绍玻尔的科学贡献。1929年，周培源最早访问了玻尔的研究所。1937年抗日战争前夕，玻尔应中国两所最高级的研究院和四所最重要的大学邀请，访问了上海、杭州、南京、北平，受到了最高规格的接待，会见了许多中国最重要的学术领导人、物理学家和学者。中国学者称玻尔是“现代科学思想的领袖”，“原子物理学的开拓者”，“世界今日最大的物理学家之一”。1938至1939年，张宗燧曾到玻尔的研究所工作，与玻尔一家建立了深厚的友谊。二次世界大战后，玻尔与中国学者断绝了来往。大战结束后，张宗燧恢复了与玻尔的通讯联系，胡宁访问了玻尔的研究所，哲学家罗忠恕在瑞典会见了玻尔。%In early 1920th, Neils Bohr and his work have been introduced into China. In 1929, Zhou Peiyuan visited Bohr＇ s institute as the first Chinese visitor. In 1937, before the Anti-Japanese War, Bohr came to China at the invitation of two of the most advanced research institutes and four of the most important universities of China. He visited Shanghai, Hangzhou, Nanjing and Beiping, received a high level reception and met with many of China＇ s academic leaders, important physicists and scholars. Bohr was evaluated as ＇ Thought leader of modem science＇ , ＇ Pioneer researcher in atomic physics＇ and ＇One of the greatest physicists in the world＇ by Chinese scholars. During 1938-1939, Zhang Zongsui has worked in Bohr＇ s institute; he established a profound friendship with Bohr. Because of the World War 2, contact between Bohr and Chinese scholars was stopped. After the war, Zhang Zongsui restarted the communication with Bohr, Hu Ning visited Bohr＇ s institute, philosopher Luo Zhongshu met with Bohr in Sweden.
Institute of Scientific and Technical Information of China (English)
范岱年
2012-01-01
Niels Bohr was very warm to new China and Chinese people since the establishment of the People＇ s Republic of China in 1949. In contrast, the Chinese scientific community also paid great respect to him in due time. Mr. Guo Moruo, for example, the first President of the Chinese Academy of Sciences, used to invite Bohr to visit China in 1957. However, since 1952, influenced by the Soviet Union and guided by Marxism ideological concepts, the Chinese academia had improperly animadverted on Bohr＇ s philosophical views. Even in the 1970s, while the Soviet academia had changed their attitude to Bohr, a few critical articles were still published in two radical Chinese journals during the last stage of the Cultural Revolution. On the other hand, when Bohr died in 1962, the Chinese scientific community sent messages of condolence to his family. From 1962 to 1995, nearly 40 Chinese scholars had visited the Niels Bohr Institute at Copenhagen. In 1985, on the occasion of the 100th anniversary of Bohr＇ s birth, Chinese physics community held a ceremonious commemoration, singing high praise for this great scientist. Professor Ge Ge devoted all his life to introduce Bohr and his works into China, in particular by translating total 12 volumes of his Collected Works. In the 21 st century, although the political critique on Bohr＇ s philosophy in China has no long existed, the evaluation about Bohr, the Copenhagen School, as well as his view of the principle of complementarity, are still the most attractive topics which may cause continual and enthusiastic discussion.%1949年以后,中华人民共和国成立,玻尔一直对新中国和中国人民友好。中国科学界也一直尊敬、仰慕玻尔。1957年中国科学院院长郭沫若曾邀请玻尔访华。杨振宁曾会见玻尔。但自1952年开始,在苏联的影响下,在中共的领导下,中国学术界开始了对玻尔哲学观点的批判,到文革后期,苏联学者从批判玻尔转变为赞扬玻尔,中
Chang, CC
2012-01-01
Model theory deals with a branch of mathematical logic showing connections between a formal language and its interpretations or models. This is the first and most successful textbook in logical model theory. Extensively updated and corrected in 1990 to accommodate developments in model theoretic methods - including classification theory and nonstandard analysis - the third edition added entirely new sections, exercises, and references. Each chapter introduces an individual method and discusses specific applications. Basic methods of constructing models include constants, elementary chains, Sko
Jaques, Thomas
2010-01-01
Generative Linguistics can and should be engaged by those with an interest in Translation Studies while developing their own positions on literary theory in general, but translation theory in particular. Generative theory provides empirical evidence for a free, creative mind that can comprehend, read, speak and translate a language. What is being proposed here contrasts radically with the dominant position of this generation's Translation Studies specialists, who freely incorporate Post-struc...
Cox, David A
2012-01-01
Praise for the First Edition ". . .will certainly fascinate anyone interested in abstract algebra: a remarkable book!"—Monatshefte fur Mathematik Galois theory is one of the most established topics in mathematics, with historical roots that led to the development of many central concepts in modern algebra, including groups and fields. Covering classic applications of the theory, such as solvability by radicals, geometric constructions, and finite fields, Galois Theory, Second Edition delves into novel topics like Abel’s theory of Abelian equations, casus irreducibili, and the Galo
Hashiguchi, Koichi
2009-01-01
This book details the mathematics and continuum mechanics necessary as a foundation of elastoplasticity theory. It explains physical backgrounds with illustrations and provides descriptions of detailed derivation processes..
DEFF Research Database (Denmark)
Stein, Irene F.; Stelter, Reinhard
2011-01-01
Communication theory covers a wide variety of theories related to the communication process (Littlejohn, 1999). Communication is not simply an exchange of information, in which we have a sender and a receiver. This very technical concept of communication is clearly outdated; a human being...
International Nuclear Information System (INIS)
After noting some advantages of using perturbation theory some of the various types are related on a chart and described, including many-body nonlinear summations, quartic force-field fit for geometry, fourth-order correlation approximations, and a survey of some recent work. Alternative initial approximations in perturbation theory are also discussed. 25 references
Manning, Phillip
2011-01-01
The study of quantum theory allowed twentieth-century scientists to examine the world in a new way, one that was filled with uncertainties and probabilities. Further study also led to the development of lasers, the atomic bomb, and the computer. This exciting new book clearly explains quantum theory and its everyday uses in our world.
Liu, Baoding
2015-01-01
When no samples are available to estimate a probability distribution, we have to invite some domain experts to evaluate the belief degree that each event will happen. Perhaps some people think that the belief degree should be modeled by subjective probability or fuzzy set theory. However, it is usually inappropriate because both of them may lead to counterintuitive results in this case. In order to rationally deal with belief degrees, uncertainty theory was founded in 2007 and subsequently studied by many researchers. Nowadays, uncertainty theory has become a branch of axiomatic mathematics for modeling belief degrees. This is an introductory textbook on uncertainty theory, uncertain programming, uncertain statistics, uncertain risk analysis, uncertain reliability analysis, uncertain set, uncertain logic, uncertain inference, uncertain process, uncertain calculus, and uncertain differential equation. This textbook also shows applications of uncertainty theory to scheduling, logistics, networks, data mining, c...
Lukeš, Jaroslav; Netuka, Ivan; Veselý, Jiří
1988-01-01
Within the tradition of meetings devoted to potential theory, a conference on potential theory took place in Prague on 19-24, July 1987. The Conference was organized by the Faculty of Mathematics and Physics, Charles University, with the collaboration of the Institute of Mathematics, Czechoslovak Academy of Sciences, the Department of Mathematics, Czech University of Technology, the Union of Czechoslovak Mathematicians and Physicists, the Czechoslovak Scientific and Technical Society, and supported by IMU. During the Conference, 69 scientific communications from different branches of potential theory were presented; the majority of them are in cluded in the present volume. (Papers based on survey lectures delivered at the Conference, its program as well as a collection of problems from potential theory will appear in a special volume of the Lecture Notes Series published by Springer-Verlag). Topics of these communications truly reflect the vast scope of contemporary potential theory. Some contributions deal...
Bohm, David
1951-01-01
This superb text by David Bohm, formerly Princeton University and Emeritus Professor of Theoretical Physics at Birkbeck College, University of London, provides a formulation of the quantum theory in terms of qualitative and imaginative concepts that have evolved outside and beyond classical theory. Although it presents the main ideas of quantum theory essentially in nonmathematical terms, it follows these with a broad range of specific applications that are worked out in considerable mathematical detail. Addressed primarily to advanced undergraduate students, the text begins with a study of t
Lubliner, Jacob
2008-01-01
The aim of Plasticity Theory is to provide a comprehensive introduction to the contemporary state of knowledge in basic plasticity theory and to its applications. It treats several areas not commonly found between the covers of a single book: the physics of plasticity, constitutive theory, dynamic plasticity, large-deformation plasticity, and numerical methods, in addition to a representative survey of problems treated by classical methods, such as elastic-plastic problems, plane plastic flow, and limit analysis; the problem discussed come from areas of interest to mechanical, structural, and
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Smith, Shelley
This paper came about within the context of a 13-month research project, Focus Area 1 - Method and Theory, at the Center for Public Space Research at the Royal Academy of the Arts School of Architecture in Copenhagen, Denmark. This project has been funded by RealDania. The goals of the research...... project, Focus Area 1 - Method and Theory, which forms the framework for this working paper, are: * To provide a basis from which to discuss the concept of public space in a contemporary architectural and urban context - specifically relating to theory and method * To broaden the discussion of the concept...
Andrews, George E
1994-01-01
Although mathematics majors are usually conversant with number theory by the time they have completed a course in abstract algebra, other undergraduates, especially those in education and the liberal arts, often need a more basic introduction to the topic.In this book the author solves the problem of maintaining the interest of students at both levels by offering a combinatorial approach to elementary number theory. In studying number theory from such a perspective, mathematics majors are spared repetition and provided with new insights, while other students benefit from the consequent simpl
Directory of Open Access Journals (Sweden)
Kathleen Holtz Deal
2007-05-01
Full Text Available Psychodynamic theory, a theory of personality originated by Sigmund Freud, has a long and complex history within social work and continues to be utilized by social workers. This article traces the theory’s development and explains key concepts with an emphasis on its current relational focus within object relations theory and self-psychology. Empirical support for theoretical concepts and the effectiveness of psychodynamic therapies is reviewed and critiqued. Future directions are discussed, including addressing cultural considerations, increasing research, and emphasizing a relational paradigm
Hočevar, Mitja
2015-01-01
This BCs thesis deals with topics from graph theory. Ramsey theory in its most basic form deals with the problem of determining the minimal positive integer, such that for any edge-coloring of the complete graph of this size with a prescribed number of colors one can find a subgraph of predefined size all of whose edges are of the same colour. These minimal sizes are called Ramsey numbers. In this BCs thesis we present basic notions of graph theory needed to understand the basic theorem of...
Victor, Oluwafemi Oludu
2015-01-01
From ages to ages there had been expectation of individuals on a specific predictions and future occurrences. So also in a game, different participant that involves in those specified game have their various expectations of the results or the output of the game they are involved in. That is why we need a mathematical theory that helps in prediction of the future expectations in our day to day activities. Therefore the Martingale Theory is a very good theory that explains and dissects the expe...
Hodges, Wilfrid
1993-01-01
An up-to-date and integrated introduction to model theory, designed to be used for graduate courses (for students who are familiar with first-order logic), and as a reference for more experienced logicians and mathematicians.
International Nuclear Information System (INIS)
This report discusses concepts in nuclear theory such as: neutrino nucleosynthesis; double beta decay; neutrino oscillations; chiral symmetry breaking; T invariance; quark propagator; cold fusion; and other related topics
DEFF Research Database (Denmark)
Hjørland, Birger
2009-01-01
Concept theory is an extremely broad, interdisciplinary and complex field of research related to many deep fields with very long historical traditions without much consensus. However, information science and knowledge organization cannot avoid relating to theories of concepts. Knowledge...... organizing systems (e.g. classification systems, thesauri and ontologies) should be understood as systems basically organizing concepts and their semantic relations. The same is the case with information retrieval systems. Different theories of concepts have different implications for how to construe......). It is also argued that the historicist and pragmatist understandings of concepts are the most fruitful views and that this understanding may be part of a broader paradigm shift that is also beginning to take place in information science. The importance of historicist and pragmatic theories of concepts...
International Nuclear Information System (INIS)
A series of lectures on plasma theory with the main headings: introduction; charged particles moving in em fields; the liquid model; transport phenomena in the plasma; wave propagation in plasmas; plasma instabilities. 57 figs. (qui)
DEFF Research Database (Denmark)
Carroll, Joseph; Clasen, Mathias; Jonsson, Emelie;
2015-01-01
Biocultural theory is an integrative research program designed to investigate the causal interactions between biological adaptations and cultural constructions. From the biocultural perspective, cultural processes are rooted in the biological necessities of the human life cycle: specifically huma...
Nel, Louis
2016-01-01
This book presents a detailed, self-contained theory of continuous mappings. It is mainly addressed to students who have already studied these mappings in the setting of metric spaces, as well as multidimensional differential calculus. The needed background facts about sets, metric spaces and linear algebra are developed in detail, so as to provide a seamless transition between students' previous studies and new material. In view of its many novel features, this book will be of interest also to mature readers who have studied continuous mappings from the subject's classical texts and wish to become acquainted with a new approach. The theory of continuous mappings serves as infrastructure for more specialized mathematical theories like differential equations, integral equations, operator theory, dynamical systems, global analysis, topological groups, topological rings and many more. In light of the centrality of the topic, a book of this kind fits a variety of applications, especially those that contribute to ...
Bouland, Olivier H.
2016-03-01
This article supplies an overview of issues related to the interpretation of surrogate measurement results for neutron-incident cross section predictions; difficulties that are somehow masked by the historical conversion route based on Weisskopf-Ewing approximation. Our proposal is to handle the various difficulties by using a more rigorous approach relying on Monte Carlo simulation of transfer reactions with extended R-matrix theory. The multiple deficiencies of the historical surrogate treatment are recalled but only one is examined in some details here; meaning the calculation of in-out-going channel Width Fluctuation Correction Factors (WFCF) which behavior witness partly the failure of Niels Bohr's compound nucleus theoretical landmark. Relevant WFCF calculations according to neutron-induced surrogate- and cross section-types as a function of neutron-induced fluctuating energy range [0 - 2.1 MeV] are presented and commented in the case of the 240Pu* and 241Pu* compound nucleus isotopes.
Gould, Ronald
2012-01-01
This introduction to graph theory focuses on well-established topics, covering primary techniques and including both algorithmic and theoretical problems. The algorithms are presented with a minimum of advanced data structures and programming details. This thoroughly corrected 1988 edition provides insights to computer scientists as well as advanced undergraduates and graduate students of topology, algebra, and matrix theory. Fundamental concepts and notation and elementary properties and operations are the first subjects, followed by examinations of paths and searching, trees, and networks. S
Effective theories of universal theories
Wells, James D.; Zhang, Zhengkang
2016-01-01
It is well-known but sometimes overlooked that constraints on the oblique parameters (most notably S and T parameters) are generally speaking only applicable to a special class of new physics scenarios known as universal theories. In the effective field theory (EFT) framework, the oblique parameters should not be associated with Wilson coefficients in a particular operator basis, unless restrictions have been imposed on the EFT so that it describes universal theories. We work out these restrictions, and present a detailed EFT analysis of universal theories. We find that at the dimension-6 level, universal theories are completely characterized by 16 parameters. They are conveniently chosen to be: 5 oblique parameters that agree with the commonly-adopted ones, 4 anomalous triple-gauge couplings, 3 rescaling factors for the h 3, hf f , hV V vertices, 3 parameters for hV V vertices absent in the Standard Model, and 1 four-fermion coupling of order y f 2 . All these parameters are defined in an unambiguous and basis-independent way, allowing for consistent constraints on the universal theories parameter space from precision electroweak and Higgs data.
Possibility Theory versus Probability Theory in Fuzzy Measure Theory
Directory of Open Access Journals (Sweden)
Parul Agarwal
2015-05-01
Full Text Available The purpose of this paper is to compare probability theory with possibility theory, and to use this comparison in comparing probability theory with fuzzy set theory. The best way of comparing probabilistic and possibilistic conceptualizations of uncertainty is to examine the two theories from a broader perspective. Such a perspective is offered by evidence theory, within which probability theory and possibility theory are recognized as special branches. While the various characteristic of possibility theory within the broader framework of evidence theory are expounded in this paper, we need to introduce their probabilistic counterparts to facilitate our discussion.
Realism and Antirealism in Informational Foundations of Quantum Theory
Directory of Open Access Journals (Sweden)
Tina Bilban
2014-08-01
so in a more comprehensive and intuitive way. The presented approach is close to Husserl's explanation of the relationship between reality and the knowledge we have about it, and to Bohr's personal explanation of quantum mechanics, the complexity of which has often been missed and simplified to mere antirealism. Our approach thus reconnects phenomenology with contemporary philosophy of science and introduces the comprehensive approach that exceeds mere realism and antirealism to the field of quantum theories with informational foundations, where such an approach has not been taken before.Quanta 2014; 3: 32–42.
Stewart, Ian
2003-01-01
Ian Stewart's Galois Theory has been in print for 30 years. Resoundingly popular, it still serves its purpose exceedingly well. Yet mathematics education has changed considerably since 1973, when theory took precedence over examples, and the time has come to bring this presentation in line with more modern approaches.To this end, the story now begins with polynomials over the complex numbers, and the central quest is to understand when such polynomials have solutions that can be expressed by radicals. Reorganization of the material places the concrete before the abstract, thus motivating the g
Effective theories of universal theories
Wells, James D
2015-01-01
It is well-known but sometimes overlooked that constraints on the oblique parameters (most notably $S$ and $T$ parameters) are only applicable to a special class of new physics scenarios known as universal theories. In the effective field theory (EFT) framework, the oblique parameters should not be associated with Wilson coefficients in a particular operator basis, unless restrictions have been imposed on the EFT so that it describes universal theories. We work out these restrictions, and present a detailed EFT analysis of universal theories. We find that at the dimension-6 level, universal theories are completely characterized by 16 parameters. They are conveniently chosen to be: 5 oblique parameters that agree with the commonly-adopted ones, 4 anomalous triple-gauge couplings, 3 rescaling factors for the $h^3$, $hff$, $hVV$ vertices, 3 parameters for $hVV$ vertices absent in the Standard Model, and 1 four-fermion coupling of order $y_f^2$. All these parameters are defined in an unambiguous and basis-indepen...
Lenz, Alexander
2016-01-01
We set the scene for theoretical issues in charm physics that were discussed at CHARM 2016 in Bologna. In particular we emphasize the importance of improving our understanding of standard model contributions to numerous charm observables and we discuss also possible tests of our theory tools, like the Heavy Quark Expansion via the lifetime ratios of $D$-mesons
DEFF Research Database (Denmark)
Monthoux, Pierre Guillet de; Statler, Matt
2014-01-01
The recent Carnegie report (Colby, et al., 2011) characterizes the goal of business education as the development of practical wisdom. In this chapter, the authors reframe Scharmer’s Theory U as an attempt to develop practical wisdom by applying certain European philosophical concepts. Specifically...
R. Veenhoven (Ruut)
2014-01-01
markdownabstract__Abstract__ Assumptions Livability theory involves the following six key assumptions: 1. Like all animals, humans have innate needs, such as for food, safety, and companionship. 2. Gratification of needs manifests in hedonic experience. 3. Hedonic experience determines how much we
Plummer, MD
1986-01-01
This study of matching theory deals with bipartite matching, network flows, and presents fundamental results for the non-bipartite case. It goes on to study elementary bipartite graphs and elementary graphs in general. Further discussed are 2-matchings, general matching problems as linear programs, the Edmonds Matching Algorithm (and other algorithmic approaches), f-factors and vertex packing.
Hashiguchi, Koichi
2014-01-01
This book was written to serve as the standard textbook of elastoplasticity for students, engineers and researchers in the field of applied mechanics. The present second edition is improved thoroughly from the first edition by selecting the standard theories from various formulations and models, which are required to study the essentials of elastoplasticity steadily and effectively and will remain universally in the history of elastoplasticity. It opens with an explanation of vector-tensor analysis and continuum mechanics as a foundation to study elastoplasticity theory, extending over various strain and stress tensors and their rates. Subsequently, constitutive equations of elastoplastic and viscoplastic deformations for monotonic, cyclic and non-proportional loading behavior in a general rate and their applications to metals and soils are described in detail, and constitutive equations of friction behavior between solids and its application to the prediction of stick-slip phenomena are delineated. In additi...
2015-01-01
A one-sentence definition of operator theory could be: The study of (linear) continuous operations between topological vector spaces, these being in general (but not exclusively) Fréchet, Banach, or Hilbert spaces (or their duals). Operator theory is thus a very wide field, with numerous facets, both applied and theoretical. There are deep connections with complex analysis, functional analysis, mathematical physics, and electrical engineering, to name a few. Fascinating new applications and directions regularly appear, such as operator spaces, free probability, and applications to Clifford analysis. In our choice of the sections, we tried to reflect this diversity. This is a dynamic ongoing project, and more sections are planned, to complete the picture. We hope you enjoy the reading, and profit from this endeavor.
Helms, Lester L
2014-01-01
Potential Theory presents a clear path from calculus to classical potential theory and beyond, with the aim of moving the reader into the area of mathematical research as quickly as possible. The subject matter is developed from first principles using only calculus. Commencing with the inverse square law for gravitational and electromagnetic forces and the divergence theorem, the author develops methods for constructing solutions of Laplace's equation on a region with prescribed values on the boundary of the region. The latter half of the book addresses more advanced material aimed at those with the background of a senior undergraduate or beginning graduate course in real analysis. Starting with solutions of the Dirichlet problem subject to mixed boundary conditions on the simplest of regions, methods of morphing such solutions onto solutions of Poisson's equation on more general regions are developed using diffeomorphisms and the Perron-Wiener-Brelot method, culminating in application to Brownian motion. In ...
Milgrom, Mordehai
2014-01-01
A general account of MOND theory is given. I start with the basic tenets of MOND, which posit departure from standard dynamics in the limit of low acceleration -- below an acceleration constant a0 -- where dynamics become scale invariant. I list some of the salient predictions of these tenets. The special role of a0 and its significance are then discussed. In particular, I stress its coincidence with cosmologically relevant accelerations. The deep-MOND limit and the consequences of its scale ...
Friedrich, Harald
2016-01-01
This corrected and updated second edition of "Scattering Theory" presents a concise and modern coverage of the subject. In the present treatment, special attention is given to the role played by the long-range behaviour of the projectile-target interaction, and a theory is developed, which is well suited to describe near-threshold bound and continuum states in realistic binary systems such as diatomic molecules or molecular ions. It is motivated by the fact that experimental advances have shifted and broadened the scope of applications where concepts from scattering theory are used, e.g. to the field of ultracold atoms and molecules, which has been experiencing enormous growth in recent years, largely triggered by the successful realization of Bose-Einstein condensates of dilute atomic gases in 1995. The book contains sections on special topics such as near-threshold quantization, quantum reflection, Feshbach resonances and the quantum description of scattering in two dimensions. The level of abstraction is k...
2014-01-01
Wolfgang Pauli referred to him as 'my discovery', Robert Oppenheimer described him as 'one of the most gifted theorists' and Niels Bohr found him enormously stimulating. Who was the man in question, Gunnar Källén (1926-1968)? His appearance in the physics sky was like a shooting star. His contributions to the scientific debate caused excitement among young and old. Similar to his friend and mentor, Wolfgang Pauli, he demanded honesty and rigour in physics - a distinct dividing line between fact and speculation. In his obituary, Arthur S. Wightman would write: "Gunnar Källén was a proud continuer of the tradition in quantum field theory established by Wolfgang Pauli. His papers on quantum electrodynamics in the period 1950-1954 carried the non-perturbative approach to quantum electrodynamics forward to a point beyond which very little essential progress has been made up to the present day. At the time I was trying ...
Goldie, Charles M
1991-01-01
This book is an introduction, for mathematics students, to the theories of information and codes. They are usually treated separately but, as both address the problem of communication through noisy channels (albeit from different directions), the authors have been able to exploit the connection to give a reasonably self-contained treatment, relating the probabilistic and algebraic viewpoints. The style is discursive and, as befits the subject, plenty of examples and exercises are provided. Some examples and exercises are provided. Some examples of computer codes are given to provide concrete illustrations of abstract ideas.
Merris, Russell
2001-01-01
A lively invitation to the flavor, elegance, and power of graph theoryThis mathematically rigorous introduction is tempered and enlivened by numerous illustrations, revealing examples, seductive applications, and historical references. An award-winning teacher, Russ Merris has crafted a book designed to attract and engage through its spirited exposition, a rich assortment of well-chosen exercises, and a selection of topics that emphasizes the kinds of things that can be manipulated, counted, and pictured. Intended neither to be a comprehensive overview nor an encyclopedic reference, th
Diestel, Reinhard
2012-01-01
HauptbeschreibungThis standard textbook of modern graph theory, now in its fourth edition, combinesthe authority of a classic with the engaging freshness of style that is the hallmarkof active mathematics. It covers the core material of the subject with concise yetreliably complete proofs, while offering glimpses of more advanced methodsin each field by one or two deeper results, again with proofs given in full detail.The book can be used as a reliable text for an introductory course, as a graduatetext, and for self-study. Rezension"Deep, clear, wonderful. This is a serious book about the
DEFF Research Database (Denmark)
Bertelsen, Olav Wedege; Bødker, Susanne
2003-01-01
The rise of personal computer challenged mainframes systems for automation of existing work routine. Furthermore it brought forth a need to focus on how to work on materials and objects through the computer. In search for theoretical and methodical perspectives it seemed promising to turn towards...... the young HCI research tradition. But HCI was already facing problems: lack of consideration for other aspects of human behavior, for interaction with other people, for culture. Cognitive science-based theories lacked means to address several issues that came out of the empirical projects....
International Nuclear Information System (INIS)
Techniques used in conventional project appraisal are mathematically very simple in comparison to those used in reservoir modelling, and in the geosciences. Clearly it would be possible to value assets in mathematically more sophisticated ways if it were meaningful and worthwhile so to do. The DCf approach in common use has recognized limitations; the inability to select a meaningful discount rate being particularly significant. Financial Theory has advanced enormously over the last few years, along with computational techniques, and methods are beginning to appear which may change the way we do project evaluations in practice. The starting point for all of this was a paper by Black and Scholes, which asserts that almost all corporate liabilities can be viewed as options of varying degrees of complexity. Although the financial presentation may be unfamiliar to engineers and geoscientists, some of the concepts used will not be. This paper outlines, in plain English, the basis of option pricing theory for assessing the market value of a project. it also attempts to assess the future role of this type of approach in practical Petroleum Exploration and Engineering economics. Reference is made to relevant published Natural Resource literature
International Nuclear Information System (INIS)
With reference to highly debated sustainable growth strategies to counter pressing interrelated global environmental and socio-economic problems, this paper reviews economic and resource development theories proposed by classical and neoclassical economists. The review evidences the growing debate among public administration decision makers regarding appropriate methods to assess the worth of natural resources and ecosystems. Proposed methods tend to be biased either towards environmental protection or economic development. Two major difficulties in the effective implementation of sustainable growth strategies are also evidenced - the management of such strategies would require appropriate revisions to national accounting systems, and the dynamic flow of energy and materials between an economic system and the environment would generate a sequence of unstable structures evolving in a chaotic and unpredictable way
St-Amant, Patrick
2010-01-01
We will see that key concepts of number theory can be defined for arbitrary operations. We give a generalized distributivity for hyperoperations (usual arithmetic operations and operations going beyond exponentiation) and a generalization of the fundamental theorem of arithmetic for hyperoperations. We also give a generalized definition of the prime numbers that are associated to an arbitrary n-ary operation and take a few steps toward the development of its modulo arithmetic by investigating a generalized form of Fermat's little theorem. Those constructions give an interesting way to interpret diophantine equations and we will see that the uniqueness of factorization under an arbitrary operation can be linked with the Riemann zeta function. This language of generalized primes and composites can be used to restate and extend certain problems such as the Goldbach conjecture.
Chong, Chi Tat; Friedman, Sy D.
1996-01-01
In this article, intended for the Handbook of Recursion Theory, we survey recursion theory on the ordinal numbers, with sections devoted to $\\alpha$-recursion theory, $\\beta$-recursion theory and the study of the admissibility spectrum.
General Theories of Regulation
Hertog, J.A. den
1999-01-01
This chapter makes a distinction between three types of theories of regulation: public interest theories, the Chicago theory of regulation and the public choice theories. The Chicago theory is mainly directed at the explanation of economic regulation; public interest theories and public choice theor
Polchinski, Joseph
1994-01-01
The first part is an introduction to conformal field theory and string perturbation theory. The second part deals with the search for a deeper answer to the question posed in the title. Contents: 1. Conformal Field Theory 2. String Theory 3. Vacua and Dualities 4. String Field Theory or Not String Field Theory 5. Matrix Models
Review of Hydroelasticity Theories
DEFF Research Database (Denmark)
Chen, Xu-jun; Wu, You-sheng; Cui, Wei-cheng;
2006-01-01
Existing hydroelastic theories are reviewed. The theories are classified into different types: two-dimensional linear theory, two-dimensional nonlinear theory, three-dimensional linear theory and three-dimensional nonlinear theory. Applications to analysis of very large floating structures (VLFS...
Condensed Matter Theories - Volume 22
Reinholz, Heidi; Röpke, Gerd; de Llano, Manuel
2007-09-01
pt. A. Fermi liquids. Pressure comparison between the spherical cellular model and the Thomas-Fermi model / G.A. Baker, Jr. Pair excitations and vertex corrections in Fermi fluids and the dynamic structure function of two-dimension 3He / H.M. Böhm, H. Godfrin, E. Krotscheck, H.J. Lauter, M. Meschke and M. Panholzer. Condensation of helium in wedges / E.S. Hernádez ... [et al.]. Non-Fermi liquid behavior from the Fermi-liquid approach / V.A. Khodel ... [et al.]. Theory of third sound and stability of thin 3He-4He superfluid films / E. Krotscheck and M.D. Miller. Pairing in asymmetrical Fermi systems / K.F. Quader and R. Liao. Ground-state properties of small 3He drops from quantum Monte Carlo simulations / E. Sola, J. Casulleras and J. Boronat. Ground-state energy and compressibility of a disordered two-dimensional electron gas / Tanatar ... [et al.]. Quasiexcitons in photoluminescence of incompressible quantum liquids / A. Wójs, A.G ladysiewicz and J.J. Quinn -- pt. B. Bose liquids. Quantum Boltzmann liquids / K.A. Gernoth, M L. Ristig and T. Lindenau. Condensate fraction in the dynamic structure function of Bose fluids / M. Saarela, F. Mazzanti and V. Apaja -- pt. C. Strongly-correlated electronic systems. Electron gas in high-field nanoscopic transport: metallic carbon nanotubes / F. Green and D. Neilson. Evolution and destruction of the Kondo effect in a capacitively coupled double dot system / D.E. Logan and M.R. Galpin. The method of increments-a wavefunction-based Ab-Initio correlation method for solids / B. Paulus. Fractionally charged excitations on frustrated lattices / E. Runge, F. Pollmann and P. Fulde. 5f Electrons in actinides: dual nature and photoemission spectra / G. Zwicknagl -- pt. D. Magnetism. Magnetism in disordered two-dimensional Kondo-Necklace / W. Brenig. On the de Haas-can Alphen oscillation in 2D / S. Fujita and D.L. Morabito. Dynamics in one-dimensional spin systems-density matrix reformalization group study / S. Nishimoto and M
THEORIES OF CORPORATE GOVERNANCE
Directory of Open Access Journals (Sweden)
Sorin Nicolae BORLEA
2013-03-01
Full Text Available This study attempts to provide a theoretical framework for the corporate governance debate. The review of various corporate governance theories enhances the major objective of corporate governance which is maximizing the value for shareholders by ensuring good social and environment performances. The theories of corporate governance are rooted in agency theory with the theory of moral hazard’s implications, further developing within stewardship theory and stakeholder theory and evolving at resource dependence theory, transaction cost theory and political theory. Later, to these theories was added ethics theory, information asymmetry theory or the theory of efficient markets. These theories are defined based on the causes and effects of variables such as: the configuration of the board of directors, audit committee, independence of managers, the role of top management and their social relations beyond the legal regulatory framework. Effective corporate governance requires applying a combination
de Boer, Jan
2002-01-01
An overview of some of the developments in string theory over the past two years is given, focusing on four topics: realistic (standard model like) models from string theory, geometric engineering and theories with fluxes, the gauge theory-gravity correspondence, and time dependent backgrounds and string theory. Plenary talk at ICHEP'02, Amsterdam, July 24-31, 2002.
Müller, Gert; Sacks, Gerald
1990-01-01
These proceedings contain research and survey papers from many subfields of recursion theory, with emphasis on degree theory, in particular the development of frameworks for current techniques in this field. Other topics covered include computational complexity theory, generalized recursion theory, proof theoretic questions in recursion theory, and recursive mathematics.
Decidability of formal theories and hyperincursivity theory
Grappone, Arturo G.
2000-05-01
This paper shows the limits of the Proof Standard Theory (briefly, PST) and gives some ideas of how to build a proof anticipatory theory (briefly, PAT) that has no such limits. Also, this paper considers that Gödel's proof of the undecidability of Principia Mathematica formal theory is not valid for axiomatic theories that use a PAT to build their proofs because the (hyper)incursive functions are self-representable.
Guerra, Francesco
2005-01-01
A coincise review about Euclidean (Quantum) Field Theory is presented. It deals with the general structural properties, the connections with Quantum Field Theory, the exploitation in Constructive Quantum Field Theory, and the physical interpretation.
Mangani, P
2011-01-01
This title includes: Lectures - G.E. Sacks - Model theory and applications, and H.J. Keisler - Constructions in model theory; and, Seminars - M. Servi - SH formulas and generalized exponential, and J.A. Makowski - Topological model theory.
Decoding the architectural theory
Institute of Scientific and Technical Information of China (English)
Gu Mengchao
2008-01-01
Starting from the illustration of the definition and concept of the architectural theory, the author established his unique understanding about the framework of the architectural theory and the innovation of the architectural theory underlined by Chinese characteristics.
Grounded theory, feminist theory, critical theory: toward theoretical triangulation.
Kushner, Kaysi Eastlick; Morrow, Raymond
2003-01-01
Nursing and social science scholars have examined the compatibility between feminist and grounded theory traditions in scientific knowledge generation, concluding that they are complementary, yet not without certain tensions. This line of inquiry is extended to propose a critical feminist grounded theory methodology. The construction of symbolic interactionist, feminist, and critical feminist variants of grounded theory methodology is examined in terms of the presuppositions of each tradition and their interplay as a process of theoretical triangulation.
THEORIES OF CORPORATE GOVERNANCE
Sorin Nicolae BORLEA; Monica-Violeta ACHIM
2013-01-01
This study attempts to provide a theoretical framework for the corporate governance debate. The review of various corporate governance theories enhances the major objective of corporate governance which is maximizing the value for shareholders by ensuring good social and environment performances. The theories of corporate governance are rooted in agency theory with the theory of moral hazard’s implications, further developing within stewardship theory and stakeholder theory and evolving at re...
Murray, Paul R.; Paul R., Murray
2001-01-01
This paper deals with two difficult questions: (1) What is literary theory? and (2) What does literary theory do? Literary theory is contrasted to literary criticism, and theory is found to be a more all-embracing, inclusive field than criticism, which is tied more closely to literature itself. Literary theory is shown to be a multitude of differing ways of looking at literature, with each theory yielding differing results.
Supersymmetric Gauge Theories from String Theory
Metzger, Steffen
2005-01-01
The subject of this thesis are various ways to construct four-dimensional quantum field theories from string theory. In a first part we study the generation of a supersymmetric Yang-Mills theory, coupled to an adjoint chiral superfield, from type IIB string theory on non-compact Calabi-Yau manifolds, with D-branes wrapping certain subcycles. Properties of the gauge theory are then mapped to the geometric structure of the Calabi-Yau space. In particular, the low energy effective superpotential...
Foundations for a theory of gravitation theories
Thorne, K. S.; Lee, D. L.; Lightman, A. P.
1972-01-01
A foundation is laid for future analyses of gravitation theories. This foundation is applicable to any theory formulated in terms of geometric objects defined on a 4-dimensional spacetime manifold. The foundation consists of (1) a glossary of fundamental concepts; (2) a theorem that delineates the overlap between Lagrangian-based theories and metric theories; (3) a conjecture (due to Schiff) that the Weak Equivalence Principle implies the Einstein Equivalence Principle; and (4) a plausibility argument supporting this conjecture for the special case of relativistic, Lagrangian-based theories.
Models of soft rotators and the theory of a harmonic rotator
Zakir, Zahid
2012-01-01
The states of a planar oscillator are separated to a vibrational mode, containing a zero-point energy, and a rotational mode without the zero-point energy, but having a conserved angular momentum. On the basis of the analysis of properties of models of rigid and semirigid rotators, the theory of soft rotators is formulated where the harmonic attractive force is balanced only by the centrifugal force. As examples a Coulomb rotator (the Bohr model) and a magneto-harmonic rotator (the Fock-Landau levels) are considered. Disappearance of the radial speed in the model of a magneto-harmonic rotator is taken as a defining property of a pure rotational motion in the harmonic potential. After the exception of energies of the magnetic and spin decompositions, specific to magnetic fields, one turns to a simple and general model of a planar harmonic rotator (circular oscillator without radial speed) where kinetic energy is reduced to the purely rotational energy. Energy levels of the harmonic rotator have the same freque...
Range-separated double-hybrid density-functional theory applied to periodic systems
Energy Technology Data Exchange (ETDEWEB)
Sansone, Giuseppe; Civalleri, Bartolomeo; Maschio, Lorenzo, E-mail: lorenzo.maschio@unito.it [Dipartimento di Chimica and NIS (Nanostructured Interfaces and Surfaces) Centre, Università di Torino, via Giuria 5, I-10125 Torino (Italy); Usvyat, Denis [Institute for Physical and Theoretical Chemistry, Universität Regensburg, Universitätsstrasse 31, D-93040 Regensburg (Germany); Toulouse, Julien [Sorbonne Universités, UPMC Univ. Paris 06, UMR 7616, Laboratoire de Chimie Théorique, F-75005 Paris (France); CNRS, UMR 7616, Laboratoire de Chimie Théorique, F-75005 Paris (France); Sharkas, Kamal [Department of Chemistry, State University of New York at Buffalo, Buffalo, New York 14260-3000 (United States)
2015-09-14
Quantum chemistry methods exploiting density-functional approximations for short-range electron-electron interactions and second-order Møller-Plesset (MP2) perturbation theory for long-range electron-electron interactions have been implemented for periodic systems using Gaussian-type basis functions and the local correlation framework. The performance of these range-separated double hybrids has been benchmarked on a significant set of systems including rare-gas, molecular, ionic, and covalent crystals. The use of spin-component-scaled MP2 for the long-range part has been tested as well. The results show that the value of μ = 0.5 bohr{sup −1} for the range-separation parameter usually used for molecular systems is also a reasonable choice for solids. Overall, these range-separated double hybrids provide a good accuracy for binding energies using basis sets of moderate sizes such as cc-pVDZ and aug-cc-pVDZ.
DGDFT: A massively parallel method for large scale density functional theory calculations
Energy Technology Data Exchange (ETDEWEB)
Hu, Wei, E-mail: whu@lbl.gov; Yang, Chao, E-mail: cyang@lbl.gov [Computational Research Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Lin, Lin, E-mail: linlin@math.berkeley.edu [Computational Research Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Department of Mathematics, University of California, Berkeley, California 94720 (United States)
2015-09-28
We describe a massively parallel implementation of the recently developed discontinuous Galerkin density functional theory (DGDFT) method, for efficient large-scale Kohn-Sham DFT based electronic structure calculations. The DGDFT method uses adaptive local basis (ALB) functions generated on-the-fly during the self-consistent field iteration to represent the solution to the Kohn-Sham equations. The use of the ALB set provides a systematic way to improve the accuracy of the approximation. By using the pole expansion and selected inversion technique to compute electron density, energy, and atomic forces, we can make the computational complexity of DGDFT scale at most quadratically with respect to the number of electrons for both insulating and metallic systems. We show that for the two-dimensional (2D) phosphorene systems studied here, using 37 basis functions per atom allows us to reach an accuracy level of 1.3 × 10{sup −4} Hartree/atom in terms of the error of energy and 6.2 × 10{sup −4} Hartree/bohr in terms of the error of atomic force, respectively. DGDFT can achieve 80% parallel efficiency on 128,000 high performance computing cores when it is used to study the electronic structure of 2D phosphorene systems with 3500-14 000 atoms. This high parallel efficiency results from a two-level parallelization scheme that we will describe in detail.
Portrait of Gunnar Källén a physics shooting star and poet of early quantum field theory
2014-01-01
Wolfgang Pauli referred to him as 'my discovery,' Robert Oppenheimer described him as 'one of the most gifted theorists' and Niels Bohr found him enormously stimulating. Who was the man in question, Gunnar Källén (1926-1968)? His appearance in the physics sky was like a shooting star. His contributions to the scientific debate caused excitement among young and old. Similar to his friend and mentor, Wolfgang Pauli, he demanded honesty and rigor in physics - a distinct dividing line between fact and speculation. In his obituary, Arthur S. Wightman would write: 'Gunnar Källén was a proud continuer of the tradition in quantum field theory established by Wolfgang Pauli. His papers on quantum electrodynamics in the period 1950-1954 carried the non-perturbative approach to quantum electrodynamics forward to a point beyond which very little essential progress has been made up to the present day. At the time I was trying to puzzle out the grammar of the language of quantum field theory, and here was Källén al...
Jardine, John F
2015-01-01
This monograph on the homotopy theory of topologized diagrams of spaces and spectra gives an expert account of a subject at the foundation of motivic homotopy theory and the theory of topological modular forms in stable homotopy theory. Beginning with an introduction to the homotopy theory of simplicial sets and topos theory, the book covers core topics such as the unstable homotopy theory of simplicial presheaves and sheaves, localized theories, cocycles, descent theory, non-abelian cohomology, stacks, and local stable homotopy theory. A detailed treatment of the formalism of the subject is interwoven with explanations of the motivation, development, and nuances of ideas and results. The coherence of the abstract theory is elucidated through the use of widely applicable tools, such as Barr's theorem on Boolean localization, model structures on the category of simplicial presheaves on a site, and cocycle categories. A wealth of concrete examples convey the vitality and importance of the subject in topology, n...
Rationality, Theory Acceptance and Decision Theory
Directory of Open Access Journals (Sweden)
J. Nicolas Kaufmann
1998-06-01
Full Text Available Following Kuhn's main thesis according to which theory revision and acceptance is always paradigm relative, I propose to outline some possible consequences of such a view. First, asking the question in what sense Bayesian decision theory could serve as the appropriate (normative theory of rationality examined from the point of view of the epistemology of theory acceptance, I argue that Bayesianism leads to a narrow conception of theory acceptance. Second, regarding the different types of theory revision, i.e. expansion, contraction, replacement and residuals shifts, I extract from Kuhn's view a series of indications showing that theory replacement cannot be rationalized within the framework of Bayesian decision theory, not even within a more sophisticated version of that model. Third, and finally, I will point to the need for a more comprehensive model of rationality than the Bayesian expected utility maximization model, the need for a model which could better deal with the different aspects of theory replacement. I will show that Kuhn's distinction between normal and revolutionary science gives us several hints for a more adequate theory of rationality in science. I will also show that Kuhn is not in a position to fully articulate his main ideas and that he well be confronted with a serious problem concerning collective choice of a paradigm.
de Bruin, B.P.
2005-01-01
Game theory is the mathematical study of strategy and conflict. It has wide applications in economics, political science, sociology, and, to some extent, in philosophy. Where rational choice theory or decision theory is concerned with individual agents facing games against nature, game theory deals
Moschovakis, YN
1987-01-01
Now available in paperback, this monograph is a self-contained exposition of the main results and methods of descriptive set theory. It develops all the necessary background material from logic and recursion theory, and treats both classical descriptive set theory and the effective theory developed by logicians.
Contemporary theories of democracy
Directory of Open Access Journals (Sweden)
Mladenović Ivan
2008-01-01
Full Text Available The aim of this paper is two-fold: first, to analyze several contemporary theories of democracy, and secondly, to propose a theoretical framework for further investigations based on analyzed theories. The following four theories will be analyzed: pluralism, social choice theory, deliberative democracy and participatory democracy.
Bursa, Francis; Kroyter, Michael
2010-01-01
String field theory is a candidate for a full non-perturbative definition of string theory. We aim to define string field theory on a space-time lattice to investigate its behaviour at the quantum level. Specifically, we look at string field theory in a one dimensional linear dilaton background. We report the first results of our simulations.
DEFF Research Database (Denmark)
Hendricks, Vincent F.
Game Theory is a collection of short interviews based on 5 questions presented to some of the most influential and prominent scholars in game theory. We hear their views on game theory, its aim, scope, use, the future direction of game theory and how their work fits in these respects....
Lassig, Michael
2011-01-01
A systematic theory is introduced that describes stochastic effects in game theory. In a biological context, such effects are relevant for the evolution of finite populations with frequency-dependent selection. They are characterized by quantum Nash equilibria, a generalization of the well-known Nash equilibrium points in classical game theory. The implications of this theory for biological systems are discussed in detail.
Zimmerman Jones, Andrew
2010-01-01
Making Everything Easier!. String Theory for Dummies. Learn:. The basic concepts of this controversial theory;. How string theory builds on physics concepts;. The different viewpoints in the field;. String theory's physical implications. Andrew Zimmerman Jones. Physics Guide, About.com. with Daniel Robbins, PhD in Physics. Your plain-English guide to this complex scientific theory. String theory is one of the most complicated sciences being explored today. Not to worry though! This informative guide clearly explains the basics of this hot topic, discusses the theory's hypotheses and prediction
Institute of Scientific and Technical Information of China (English)
梁景宏
2010-01-01
In this essay, I wish to invite young scholars to learn, use, and contribute to accounting theory. In this invitation, I argue theory has lineage, is important and can be fun. Its lineage comes from the post-WWII scientific revolution in management education and research. Theory is important because it is the successful interaction between theory and empirical work that ultimately advances an academic discipline. Theory can be fun because when done well, learning, using and contributing to theory can be an enjoyable activity for all scholars, either as consumers or as producers of theory.
Noncommutative Gauge Theories in Matrix Theory
Ho, P M; Ho, Pei-Ming; Wu, Yong-Shi
1998-01-01
We present a general framework for Matrix theory compactified on a quotient space of n dimensional Euclidean space over G, with G a discrete group of Euclidean motions. The general solution to the quotient conditions gives a gauge theory on a noncommutative space. We characterize the resulting noncommutative gauge theory in terms of the twisted group algebra of G associated with a projective regular representation.
Institute of Scientific and Technical Information of China (English)
无
2003-01-01
The basic ideas of game theory were originated from the problems of maximum and minimum given by J.Yon Neumann in 1928. Later, wars accelerated the study of game theory, there are many developments that contributed to the advancement of game theory, many problems of optimum appeared in economic development process. Scientists applied mathematic methods to studying game theory to make the theory more profound and perfect. The axiomatic structure of game theory was nearly complete in 1944. The path of the development of game theory started from finite to infinite, from two players to many players, from expressing gains with quantity to showing the ending of game theory with abstract result, and from certainty problems to random problems. Thus development of game theory is closely related to the economic development. In recent years, the research on the non-differentiability of Shapley value posed by Belgian Mertens is one of the advanced studies in game theory.
Gauge theory loop operators and Liouville theory
International Nuclear Information System (INIS)
We propose a correspondence between loop operators in a family of four dimensional N=2 gauge theories on S4 - including Wilson, 't Hooft and dyonic operators - and Liouville theory loop operators on a Riemann surface. This extends the beautiful relation between the partition function of these N=2 gauge theories and Liouville correlators found by Alday, Gaiotto and Tachikawa. We show that the computation of these Liouville correlators with the insertion of a Liouville loop operator reproduces Pestun's formula capturing the expectation value of a Wilson loop operator in the corresponding gauge theory. We prove that our definition of Liouville loop operators is invariant under modular transformations, which given our correspondence, implies the conjectured action of S-duality on the gauge theory loop operators. Our computations in Liouville theory make an explicit prediction for the exact expectation value of 't Hooft and dyonic loop operators in these N=2 gauge theories. The Liouville loop operators are also found to admit a simple geometric interpretation within quantum Teichmueller theory as the quantum operators representing the length of geodesics. We study the algebra of Liouville loop operators and show that it gives evidence for our proposal as well as providing definite predictions for the operator product expansion of loop operators in gauge theory. (orig.)
DEFF Research Database (Denmark)
Andersen, Jack
2015-01-01
Purpose To provide a small overview of genre theory and its associated concepts and to show how genre theory has had its antecedents in certain parts of the social sciences and not in the humanities. Findings The chapter argues that the explanatory force of genre theory may be explained with its...... emphasis on everyday genres, de facto genres. Originality/value By providing an overview of genre theory, the chapter demonstrates the wealth and richness of forms of explanations in genre theory....
Ali Rabbani Khorasghani; Mohammad Abbaszadeh
2010-01-01
AbstractAccording to social changes in global level, social scientist introduced new theories to explanation of socialphenomena. According to appearance new theories, research methods have changed. The Idea is that,Simultaneity with Appearance post positivist theories, research approaches such a grounded theory hasestablished. This method, acts in the base of qualitative methods and use systematic complex of multipleProcedures to gathering data for theory development upon induction. This meth...
Conlon, Joseph
2016-01-01
Is string theory a fraud or one of the great scientific advances? Why do so many physicists work on string theory if it cannot be tested? This book provides insight into why such a theory, with little direct experimental support, plays such a prominent role in theoretical physics. The book gives a modern and accurate account of string theory and science, explaining what string theory is, why it is regarded as so promising, and why it is hard to test.
Teaching Theory X and Theory Y in Organizational Communication
Noland, Carey
2014-01-01
The purpose of the activity described here is to integrate McGregor's Theory X and Theory Y into a group application: design a syllabus that embodies either Theory X or Theory Y tenets. Students should be able to differentiate between Theory X and Theory Y, create a syllabus based on Theory X or Theory Y tenets, evaluate the different syllabi…
Generalizability Theory and Classical Test Theory
Brennan, Robert L.
2011-01-01
Broadly conceived, reliability involves quantifying the consistencies and inconsistencies in observed scores. Generalizability theory, or G theory, is particularly well suited to addressing such matters in that it enables an investigator to quantify and distinguish the sources of inconsistencies in observed scores that arise, or could arise, over…
[Topics in field theory and string theory
International Nuclear Information System (INIS)
In the past year, I have continued to investigate the relations between conformal field theories and lattice statistical mechanical models. I have also tried to extend some of these results to higher dimensions and to find applications in string theories and other contexts
Generalizability theory and item response theory
Glas, C.A.W.; Eggen, T.J.H.M.; Veldkamp, B.P.
2012-01-01
Item response theory is usually applied to items with a selected-response format, such as multiple choice items, whereas generalizability theory is usually applied to constructed-response tasks assessed by raters. However, in many situations, raters may use rating scales consisting of items with a s
Elements of a theory of algebraic theories
Hyland, Martin
2013-01-01
Kleisli bicategories are a natural environment in which the combinatorics involved in various notions of algebraic theory can be handled in a uniform way. The setting allows a clear account of comparisons between such notions. Algebraic theories, symmetric operads and nonsymmetric operads are treated as examples.
Fabris, J C
2015-01-01
General Relativity is the modern theory of gravitation. It has replaced the newtonian theory in the description of the gravitational phenomena. In spite of the remarkable success of the General Relativity Theory, the newtonian gravitational theory is still largely employed, since General Relativity, in most of the cases, just makes very small corrections to the newtonian predictions. Moreover, the newtonian theory is much simpler, technically and conceptually, when compared to the relativistic theory. In this text, we discuss the possibility of extending the traditional newtonian theory in order to incorporate typical relativistic effects, but keeping the simplicity of the newtonian framework. We denominate these extensions neo-newtonian theories. These theories are discussed mainly in the contexts of cosmology and compact astrophysical objects.
Directory of Open Access Journals (Sweden)
Ali Rabbani Khorasghani
2010-01-01
Full Text Available AbstractAccording to social changes in global level, social scientist introduced new theories to explanation of socialphenomena. According to appearance new theories, research methods have changed. The Idea is that,Simultaneity with Appearance post positivist theories, research approaches such a grounded theory hasestablished. This method, acts in the base of qualitative methods and use systematic complex of multipleProcedures to gathering data for theory development upon induction. This method with characteristics as ifflexibility, reflexivity, has caused many of researchers used it. In the present article, we paid to introductionof grounded theory and its critics.
Directory of Open Access Journals (Sweden)
Regina Szylit Bousso
2014-02-01
Full Text Available The theory framework of nursing science is built in a dynamic process that arises from practice and is reproduced through research, mainly by analysis and development of concepts and theories. This study presents a theory reflection on nursing knowledge construction and points out subsidies for future studies in the area. The interrelation among theory, research, and clinical practice is required for continuous development of nursing as a profession and science. Ideally, the practice must be based on theory that is validated by research. Therefore, theory, research, and practice affect each other reciprocally and continuously.
Diffraction Theory and Almost Periodic Distributions
Strungaru, Nicolae; Terauds, Venta
2016-09-01
We introduce and study the notions of translation bounded tempered distributions, and autocorrelation for a tempered distribution. We further introduce the spaces of weakly, strongly and null weakly almost periodic tempered distributions and show that for weakly almost periodic tempered distributions the Eberlein decomposition holds. For translation bounded measures all these notions coincide with the classical ones. We show that tempered distributions with measure Fourier transform are weakly almost periodic and that for this class, the Eberlein decomposition is exactly the Fourier dual of the Lebesgue decomposition, with the Fourier-Bohr coefficients specifying the pure point part of the Fourier transform. We complete the project by looking at few interesting examples.
Supersymmetric gauge theories from string theory
International Nuclear Information System (INIS)
This thesis presents various ways to construct four-dimensional quantum field theories from string theory. In a first part we study the generation of a supersymmetric Yang-Mills theory, coupled to an adjoint chiral superfield, from type IIB string theory on non-compact Calabi-Yau manifolds, with D-branes wrapping certain sub-cycles. Properties of the gauge theory are then mapped to the geometric structure of the Calabi-Yau space. Even if the Calabi-Yau geometry is too complicated to evaluate the geometric integrals explicitly, one can then always use matrix model perturbation theory to calculate the effective superpotential. The second part of this work covers the generation of four-dimensional super-symmetric gauge theories, carrying several important characteristic features of the standard model, from compactifications of eleven-dimensional supergravity on G2-manifolds. If the latter contain conical singularities, chiral fermions are present in the four-dimensional gauge theory, which potentially lead to anomalies. We show that, locally at each singularity, these anomalies are cancelled by the non-invariance of the classical action through a mechanism called 'anomaly inflow'. Unfortunately, no explicit metric of a compact G2-manifold is known. Here we construct families of metrics on compact weak G2-manifolds, which contain two conical singularities. Weak G2-manifolds have properties that are similar to the ones of proper G2-manifolds, and hence the explicit examples might be useful to better understand the generic situation. Finally, we reconsider the relation between eleven-dimensional supergravity and the E8 x E8-heterotic string. This is done by carefully studying the anomalies that appear if the supergravity theory is formulated on a ten-manifold times the interval. Again we find that the anomalies cancel locally at the boundaries of the interval through anomaly inflow, provided one suitably modifies the classical action. (author)
Covariant Noncommutative Field Theory
International Nuclear Information System (INIS)
The covariant approach to noncommutative field and gauge theories is revisited. In the process the formalism is applied to field theories invariant under diffeomorphisms. Local differentiable forms are defined in this context. The lagrangian and hamiltonian formalism is consistently introduced
Introduction to percolation theory
Stauffer, Dietrich
1991-01-01
Percolation theory deals with clustering, criticallity, diffusion, fractals, phase transitions and disordered systems. This book covers the basic theory for the graduate, and also professionals dealing with it for the first time
Combinatorics and field theory
Bender, Carl M.; Brody, Dorje C.; Meister, Bernhard K.
2006-01-01
For any given sequence of integers there exists a quantum field theory whose Feynman rules produce that sequence. An example is illustrated for the Stirling numbers. The method employed here offers a new direction in combinatorics and graph theory.
DEFF Research Database (Denmark)
Clemmensen, Torkil; Kaptelinin, Victor; Nardi, Bonnie
2016-01-01
This paper reports a study of the use of activity theory in human–computer interaction (HCI) research. We analyse activity theory in HCI since its first appearance about 25 years ago. Through an analysis and meta-synthesis of 109 selected HCI activity theory papers, we created a taxonomy of 5...... different ways of using activity theory: (1) analysing unique features, principles, and problematic aspects of the theory; (2) identifying domain-specific requirements for new theoretical tools; (3) developing new conceptual accounts of issues in the field of HCI; (4) guiding and supporting empirical...... analyses of HCI phenomena; and (5) providing new design illustrations, claims, and guidelines. We conclude that HCI researchers are not only users of imported theory, but also theory-makers who adapt and develop theory for different purposes....
Zielenkiewicz, Wojciech
2004-01-01
The purpose of this book is to give a comprehensive description of the theoretical fundamentals of calorimetry. The considerations are based on the relations deduced from the laws and general equations of heat exchange theory and steering theory.
Theories of Career Development. A Comparison of the Theories.
Osipow, Samuel H.
These seven theories of career development are examined in previous chapters: (1) Roe's personality theory, (2) Holland's career typology theory, (3) the Ginzberg, Ginsburg, Axelrod, and Herma Theory, (4) psychoanalytic conceptions, (5) Super's developmental self-concept theory, (6) other personality theories, and (7) social systems theories.…
Quantum algorithmic information theory
Svozil, Karl
1995-01-01
The agenda of quantum algorithmic information theory, ordered `top-down,' is the quantum halting amplitude, followed by the quantum algorithmic information content, which in turn requires the theory of quantum computation. The fundamental atoms processed by quantum computation are the quantum bits which are dealt with in quantum information theory. The theory of quantum computation will be based upon a model of universal quantum computer whose elementary unit is a two-port interferometer capa...
Güth, Werner
2000-01-01
Whereas orthodox game theory relies on the unrealistic assumption of (commonly known) perfect rationality, participants in game playing experiments are at best boundedly rational. This makes it necessary to supplement orthodox game theory by a behavioral theory of game playing. We first point out that this applies also to (one person-) decision theory. After reviewing the influential experiments based on repeated games and the ultimatum game the typical reactions to the striking experimental ...
Linker, Patrick
2016-01-01
A couple of quantum gravity theories were proposed to make theoretical predictions about the behavior of gravity. The most recent approach to quantum gravity, called E-theory, is proposed mathematical, but there is not formulated much about what dynamics of gravity this theory proposes. This research paper treats the main results of the application of E-theory to General relativity involving conservation laws and scattering of particles in presence of gravity. Also the low-energy limit of thi...
International Nuclear Information System (INIS)
Areas of emphasis include acceleration algorithms for the Monte Carlo analysis of lattice field and gauge theories, quaternionic generalizations of complex quantum mechanics and field theory, application of the renormalization group to the QCD phase transition, the quantum Hall effect, and black holes. Other work involved string theory, statistical properties of energy levels in integrable quantum systems, baryon asymmetry and the electroweak phase transition, anisotropies of the cosmic microwave background, and theory of superconductors
Thulasiraman, K
2011-01-01
This adaptation of an earlier work by the authors is a graduate text and professional reference on the fundamentals of graph theory. It covers the theory of graphs, its applications to computer networks and the theory of graph algorithms. Also includes exercises and an updated bibliography.
Comparing Measurement Theories.
Schumacker, Randall E.
In comparing measurement theories, it is evident that the awareness of the concept of measurement error during the time of Galileo has lead to the formulation of observed scores comprising a true score and error (classical theory), universe score and various random error components (generalizability theory), or individual latent ability and error…
Matsumoto, Kohji
2002-01-01
The book includes several survey articles on prime numbers, divisor problems, and Diophantine equations, as well as research papers on various aspects of analytic number theory such as additive problems, Diophantine approximations and the theory of zeta and L-function Audience Researchers and graduate students interested in recent development of number theory
Superspace conformal field theory
Energy Technology Data Exchange (ETDEWEB)
Quella, Thomas [Koeln Univ. (Germany). Inst. fuer Theoretische Physik; Schomerus, Volker [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
2013-07-15
Conformal sigma models and WZW models on coset superspaces provide important examples of logarithmic conformal field theories. They possess many applications to problems in string and condensed matter theory. We review recent results and developments, including the general construction of WZW models on type I supergroups, the classification of conformal sigma models and their embedding into string theory.
Battenfeld, Ingo
2008-01-01
This thesis presents Topological Domain Theory as a powerful and flexible framework for denotational semantics. Topological Domain Theory models a wide range of type constructions and can interpret many computational features. Furthermore, it has close connections to established frameworks for denotational semantics, as well as to well-studied mathematical theories, such as topology and computable analysis.
Maasland, E.
2012-01-01
Auction theory is a branch of game theory that considers human behavior in auction markets and the ensuing market outcomes. It is also successfully used as a tool to design real-life auctions. This thesis contains five essays addressing a variety of topics within the realm of auction theory. The fir
Algorithmic information theory
P.D. Grünwald; P.M.B. Vitányi
2008-01-01
We introduce algorithmic information theory, also known as the theory of Kolmogorov complexity. We explain the main concepts of this quantitative approach to defining `information'. We discuss the extent to which Kolmogorov's and Shannon's information theory have a common purpose, and where they are
Algorithmic information theory
P.D. Grünwald; P.M.B. Vitányi
2008-01-01
We introduce algorithmic information theory, also known as the theory of Kolmogorov complexity. We explain the main concepts of this quantitative approach to defining 'information'. We discuss the extent to which Kolmogorov's and Shannon's information theory have a common purpose, and where they are
Sobreiro, R. F.; Tomaz, A. A.; Otoya, V. J. Vasquez
2012-01-01
Pure gauge theories for de Sitter, anti de Sitter and orthogonal groups, in four-dimensional Euclidean spacetime, are studied. It is shown that, if the theory is asymptotically free and a dynamical mass is generated, then an effective geometry may be induced and a gravity theory emerges.
Reflections on Activity Theory
Bakhurst, David
2009-01-01
It is sometimes suggested that activity theory represents the most important legacy of Soviet philosophy and psychology. But what exactly "is" activity theory? The canonical account in the West is given by Engestrom, who identifies three stages in the theory's development: from Vygotsky's insights, through Leontiev's articulation of the…
Peim, Nick
2009-01-01
This paper seeks to re-examine Yrio Engestrom's activity theory as a technology of knowledge designed to enable positive transformations of specific practices. The paper focuses on a key paper where Engestrom defines the nature and present state of activity theory. Beginning with a brief account of the relations between activity theory and…
Superspace conformal field theory
International Nuclear Information System (INIS)
Conformal sigma models and WZW models on coset superspaces provide important examples of logarithmic conformal field theories. They possess many applications to problems in string and condensed matter theory. We review recent results and developments, including the general construction of WZW models on type I supergroups, the classification of conformal sigma models and their embedding into string theory.
Missinne, Leo E.; Wilcox, Victoria
This paper discusses the life, theories, and therapeutic techniques of psychotherapist, Viktor E. Frankl. A brief biography of Frankl is included discussing the relationship of his early experiences as a physician to his theory of personality. Frankl's theory focusing on man's need for meaning and emphasizing the spiritual dimension in each human…
Positioning Theory in Paradigms
Institute of Scientific and Technical Information of China (English)
FU Xiao-qiu
2015-01-01
This article discusses the importance of theory and paradigm to a researcher. It starts from introducing and analyzing the definition of the two terms, by using the theories in the field of intercultural communication as examples. To a good researcher, he needs not only clarifying the paradigm his research is positioned, but also integrating the theories in his paradigm.
Vazzana, Anthony; Garth, David
2007-01-01
One of the oldest branches of mathematics, number theory is a vast field devoted to studying the properties of whole numbers. Offering a flexible format for a one- or two-semester course, Introduction to Number Theory uses worked examples, numerous exercises, and two popular software packages to describe a diverse array of number theory topics.
Theory and context / Theory in context
DEFF Research Database (Denmark)
Glaveanu, Vlad Petre
2014-01-01
It is debatable whether the psychology of creativity is a field in crisis or not. There are clear signs of increased fragmenta-tion and a scarcity of integrative efforts, but is this necessari-ly bad? Do we need more comprehensive theories of creativ-ity and a return to old epistemological...... questions? This de-pends on how one understands theory. Against a view of theoretical work as aiming towards generality, universality, uniformity, completeness, and singularity, I advocate for a dynamic perspective in which theory is plural, multifaceted, and contextual. Far from ‘waiting for the Messiah......’, theoreti-cal work in the psychology of creativity can be integrative without having the ambition to explain or, even more, predict, creative expression across all people, at all times, and in all domains. To avoid such ambition, the psychology of creativi-ty requires a theory of context that doesn...
Rotor theories by Professor Joukowsky: Momentum theories
DEFF Research Database (Denmark)
van Kuik, G. A. M.; Sørensen, Jens Nørkær; Okulov, V. L.
2015-01-01
This paper is the first of two papers on the history of rotor aerodynamics with special emphasis on the role of Joukowsky. The present one focuses on the development of the momentum theory while the second one surveys the development of vortex theory for rotors. Joukowsky has played a major role......, and the contributions by individual researchers like Lanchester, Prandtl, Betz and Joukowslcy himself. After the one-dimensional momentum theory was well established, the introduction of torque and angular momentum was the next step. Joukowslcy has led the basis for this step, but Glauert's Blade Element Momentum still...... of inviscid flow. For very low tip speed ratios the general momentum theory gives unphysical results which disappear after applying a perturbation parameter representing phenomena not captured by the Euler equations. (C) 2014 Elsevier Ltd. All rights reserved....
La theorie autrement (Theory in Another Light).
Bertocchini, Paola; Costanzo, Edwige
1985-01-01
Outlines a technique using articles from "Le Francais dans le Monde" to teach reading comprehension and theory simultaneously to teachers of French as a second language. Describes a program in Italy using this approach. (MSE)
Family systems theory, attachment theory, and culture.
Rothbaum, Fred; Rosen, Karen; Ujiie, Tatsuo; Uchida, Nobuko
2002-01-01
Family systems theory and attachment theory have important similarities and complementarities. Here we consider two areas in which the theories converge: (a) in family system theorists' description of an overly close, or "enmeshed," mother-child dyad, which attachment theorists conceptualize as the interaction of children's ambivalent attachment and mothers' preoccupied attachment; (b) in family system theorists' description of the "pursuer-distance cycle" of marital conflict, which attachment theorists conceptualize as the interaction of preoccupied and dismissive partners. We briefly review family systems theory evidence, and more extensively review attachment theory evidence, pertaining to these points of convergence. We also review cross-cultural research, which leads us to conclude that the dynamics described in both theories reflect, in part, Western ways of thinking and Western patterns of relatedness. Evidence from Japan suggests that extremely close ties between mother and child are perceived as adaptive, and are more common, and that children experience less adverse effects from such relationships than do children in the West. Moreover, in Japan there is less emphasis on the importance of the exclusive spousal relationship, and less need for the mother and father to find time alone to rekindle romantic, intimate feelings and to resolve conflicts by openly communicating their differences. Thus, the "maladaptive" pattern frequently cited by Western theorists of an extremely close mother-child relationship, an unromantic, conflictual marriage characterized by little verbal communication and a peripheral, distant father, may function very differently in other cultures. While we believe that both theories will be greatly enriched by their integration, we caution against the application of either theory outside the cultures in which they were developed.
Irvine, J M
1972-01-01
Nuclear Structure Theory provides a guide to nuclear structure theory. The book is comprised of 23 chapters that are organized into four parts; each part covers an aspect of nuclear structure theory. In the first part, the text discusses the experimentally observed phenomena, which nuclear structure theories need to look into and detail the information that supports those theories. The second part of the book deals with the phenomenological nucleon-nucleon potentials derived from phase shift analysis of nucleon-nucleon scattering. Part III talks about the phenomenological parameters used to de
Prest, M
1988-01-01
In recent years the interplay between model theory and other branches of mathematics has led to many deep and intriguing results. In this, the first book on the topic, the theme is the interplay between model theory and the theory of modules. The book is intended to be a self-contained introduction to the subject and introduces the requisite model theory and module theory as it is needed. Dr Prest develops the basic ideas concerning what can be said about modules using the information which may be expressed in a first-order language. Later chapters discuss stability-theoretic aspects of module
Bollobas, Bela
2004-01-01
The ever-expanding field of extremal graph theory encompasses a diverse array of problem-solving methods, including applications to economics, computer science, and optimization theory. This volume, based on a series of lectures delivered to graduate students at the University of Cambridge, presents a concise yet comprehensive treatment of extremal graph theory.Unlike most graph theory treatises, this text features complete proofs for almost all of its results. Further insights into theory are provided by the numerous exercises of varying degrees of difficulty that accompany each chapter. A
Kilmister, Clive William
1970-01-01
Special Theory of Relativity provides a discussion of the special theory of relativity. Special relativity is not, like other scientific theories, a statement about the matter that forms the physical world, but has the form of a condition that the explicit physical theories must satisfy. It is thus a form of description, playing to some extent the role of the grammar of physics, prescribing which combinations of theoretical statements are admissible as descriptions of the physical world. Thus, to describe it, one needs also to describe those specific theories and to say how much they are limit
Generalized Teleparallel Theory
Junior, Ednaldo L B
2015-01-01
We construct a theory in which the gravitational interaction is described only by torsion, but that generalizes the Teleparallel Theory still keeping the invariance of local Lorentz transformations. We show that our theory falls, to a certain limit of a real parameter, in the $f(R)$ Gravity or, to another limit of the same real parameter, in a modified $f(T)$ Gravity, interpolating between these two theories and still can fall on several other theories. We explicitly show the equivalence with $f(R)$ Gravity for cases of Friedmann-Lemaitre-Robertson-Walker flat metric for diagonal tetrads, and a metric with spherical symmetry for diagonal and non-diagonal tetrads.
Variational Transition State Theory
Energy Technology Data Exchange (ETDEWEB)
Truhlar, Donald G. [Univ. of Minnesota, Minneapolis, MN (United States)
2016-09-29
This is the final report on a project involving the development and applications of variational transition state theory. This project involved the development of variational transition state theory for gas-phase reactions, including optimized multidimensional tunneling contributions and the application of this theory to gas-phase reactions with a special emphasis on developing reaction rate theory in directions that are important for applications to combustion. The development of variational transition state theory with optimized multidimensional tunneling as a useful computational tool for combustion kinetics involved eight objectives.
Gross, Jonathan L
2003-01-01
The Handbook of Graph Theory is the most comprehensive single-source guide to graph theory ever published. Best-selling authors Jonathan Gross and Jay Yellen assembled an outstanding team of experts to contribute overviews of more than 50 of the most significant topics in graph theory-including those related to algorithmic and optimization approaches as well as ""pure"" graph theory. They then carefully edited the compilation to produce a unified, authoritative work ideal for ready reference.Designed and edited with non-experts in mind, the Handbook of Graph Theory makes information easy to fi
Directory of Open Access Journals (Sweden)
Antonio De Felice
2010-06-01
Full Text Available Over the past decade, f(R theories have been extensively studied as one of the simplest modifications to General Relativity. In this article we review various applications of f(R theories to cosmology and gravity – such as inflation, dark energy, local gravity constraints, cosmological perturbations, and spherically symmetric solutions in weak and strong gravitational backgrounds. We present a number of ways to distinguish those theories from General Relativity observationally and experimentally. We also discuss the extension to other modified gravity theories such as Brans–Dicke theory and Gauss–Bonnet gravity, and address models that can satisfy both cosmological and local gravity constraints.
Generalization Rough Set Theory
Institute of Scientific and Technical Information of China (English)
XIAO Di; ZHANG Jun-feng; HU Shou-song
2008-01-01
In order to avoid the discretization in the classical rough set theory, a generlization rough set theory is proposed.At first, the degree of general importance of an attribute and attribute subsets are presented.Then, depending on the degree of general importance of attribute, the space distance can be measured with weighted method.At last, a generalization rough set theory based on the general near neighborhood relation is proposed.The proposed theory partitions the universe into the tolerant modules, and forms lower approximation and upper approximation of the set under general near neighborhood relationship, which avoids the discretization in Pawlak's rough set theory.
Barron, E N
2013-01-01
An exciting new edition of the popular introduction to game theory and its applications The thoroughly expanded Second Edition presents a unique, hands-on approach to game theory. While most books on the subject are too abstract or too basic for mathematicians, Game Theory: An Introduction, Second Edition offers a blend of theory and applications, allowing readers to use theory and software to create and analyze real-world decision-making models. With a rigorous, yet accessible, treatment of mathematics, the book focuses on results that can be used to
Förste, S; Forste, Stefan; Louis, Jan
1996-01-01
In this lecture we review some of the recent developments in string theory on an introductory and qualitative level. In particular we focus on S-T-U dualities of toroidally compactified ten-dimensional string theories and outline the connection to M-theory. Dualities among string vacua with less supersymmetries in six and four space-time dimensions is discussed and the concept of F-theory is briefly presented. (Lecture given by J. Louis at the Workshop on Gauge Theories, Applied Supersymmetry and Quantum Gravity, Imperial College, London, UK, July 5--10, 1996.)
Introduction to bifurcation theory
International Nuclear Information System (INIS)
Bifurcation theory is a subject with classical mathematical origins. The modern development of the subject starts with Poincare and the qualitative theory of differential equations. In recent years, the theory has undergone a tremendous development with the infusion of new ideas and methods from dynamical systems theory, singularity theory, group theory, and computer-assisted studies of dynamics. As a result, it is difficult to draw the boundaries of the theory with any confidence. In this review, the objects in question will be parameterized families of dynamical systems (vector fields or maps). In the sciences these families commonly arise when one formulates equations of motion to model a physical system. We specifically analyze how the time evolution near an equilibrium can change as parameters are varied; for simplicity we consider the case of a single parameter only
Niederreiter, Harald
2015-01-01
This textbook effectively builds a bridge from basic number theory to recent advances in applied number theory. It presents the first unified account of the four major areas of application where number theory plays a fundamental role, namely cryptography, coding theory, quasi-Monte Carlo methods, and pseudorandom number generation, allowing the authors to delineate the manifold links and interrelations between these areas. Number theory, which Carl-Friedrich Gauss famously dubbed the queen of mathematics, has always been considered a very beautiful field of mathematics, producing lovely results and elegant proofs. While only very few real-life applications were known in the past, today number theory can be found in everyday life: in supermarket bar code scanners, in our cars’ GPS systems, in online banking, etc. Starting with a brief introductory course on number theory in Chapter 1, which makes the book more accessible for undergraduates, the authors describe the four main application areas in Chapters...
Computational invariant theory
Derksen, Harm
2015-01-01
This book is about the computational aspects of invariant theory. Of central interest is the question how the invariant ring of a given group action can be calculated. Algorithms for this purpose form the main pillars around which the book is built. There are two introductory chapters, one on Gröbner basis methods and one on the basic concepts of invariant theory, which prepare the ground for the algorithms. Then algorithms for computing invariants of finite and reductive groups are discussed. Particular emphasis lies on interrelations between structural properties of invariant rings and computational methods. Finally, the book contains a chapter on applications of invariant theory, covering fields as disparate as graph theory, coding theory, dynamical systems, and computer vision. The book is intended for postgraduate students as well as researchers in geometry, computer algebra, and, of course, invariant theory. The text is enriched with numerous explicit examples which illustrate the theory and should be ...
[Introduction to grounded theory].
Wang, Shou-Yu; Windsor, Carol; Yates, Patsy
2012-02-01
Grounded theory, first developed by Glaser and Strauss in the 1960s, was introduced into nursing education as a distinct research methodology in the 1970s. The theory is grounded in a critique of the dominant contemporary approach to social inquiry, which imposed "enduring" theoretical propositions onto study data. Rather than starting from a set theoretical framework, grounded theory relies on researchers distinguishing meaningful constructs from generated data and then identifying an appropriate theory. Grounded theory is thus particularly useful in investigating complex issues and behaviours not previously addressed and concepts and relationships in particular populations or places that are still undeveloped or weakly connected. Grounded theory data analysis processes include open, axial and selective coding levels. The purpose of this article was to explore the grounded theory research process and provide an initial understanding of this methodology.
Johnson, C V
2006-01-01
We present a class of solvable models that resemble string theories in many respects but have a strikingly different non-perturbative sector. In particular, there are no exponentially small contributions to perturbation theory in the string coupling, which normally are associated with branes and related objects. Perturbation theory is no longer an asymptotic expansion, and so can be completely re-summed to yield all the non-perturbative physics. We examine a number of other properties of the theories, for example constructing and examining the physics of loop operators, which can be computed exactly, and gain considerable understanding of the difference between these new theories and the more familiar ones, including the possibility of how to interpolate between the two types. Interestingly, the models we exhibit contain a family of zeros of the partition function which suggest a novel phase structure. The theories are defined naturally by starting with models that yield well-understood string theories and al...
A Reconciliation of Collision Theory and Transition State Theory
Yi, Y. G.
2001-01-01
A statistical-mechanical treatment of collision leads to a formal connection with transition-state theory, suggesting that collision theory and transition-state theory might be joined ultimately as a collision induced transition state theory.
EIA THEORIES — ALL CHINESE WHISPERS AND NO CRITICAL THEORY
JOE WESTON
2010-01-01
There have been a large number of attempts to develop a theory or theories of Environmental Impact Assessment in order to justify its use in environmental decision-making. A review of academic articles demonstrates that these theories are largely drawn from planning theories. Planning theories are themselves a development of sociological theories of decision-making and from one particular strand of sociological theory. In this review of the theories of EIA it is argued that an understanding o...
Institute of Scientific and Technical Information of China (English)
王贵友
2001-01-01
玻尔在科学观念上实现了从微观现象个体性概念到系统目的性概念的过渡，实现了还原论与机体论、因果决定论与目的论的“两性相通”。这主要基于他对微观现象个体性之观测条件及量子力学形式系统之操作定义的互补解释。在这里，因果分析方法具有根本上的局限性，并与目的论整体方法之间保持特定“张力”，个体性的“定态”与“跃迁”概念同作为目的性概念基础的结构稳定与变换思想具有可通约性。%Bohr's scientific idea have a transition from the Concept of Micro-phenomenal Individuality to the one of Systematic Teleology,realized "two-polarities-open-out-to-each-other/" between reductionism and organism and between determinism and teleology.This based mainly on his complementary interpretation given to the measurement conditions of the Micro-phenomenal Individuality and on the operational definition of quantum mechanics' form system.The cause-end analysis here has fundamentally a limitation,and keeps a special "tension" with teleological unity.The concepts of individual "fixity" and "transitivity" are reducible to the idea of structural stability and mobility that is the foundation of the teleology.
Blagojević, Milutin
2012-01-01
During the last five decades, gravity, as one of the fundamental forces of nature, has been formulated as a gauge field theory of the Weyl-Cartan-Yang-Mills type. The resulting theory, the Poincar\\'e gauge theory of gravity, encompasses Einstein's gravitational theory as well as the teleparallel theory of gravity as subcases. In general, the spacetime structure is enriched by Cartan's torsion and the new theory can accommodate fermionic matter and its spin in a perfectly natural way. The present reprint volume contains articles from the most prominent proponents of the theory and is supplemented by detailed commentaries of the editors. This guided tour starts from special relativity and leads, in its first part, to general relativity and its gauge type extensions a la Weyl and Cartan. Subsequent stopping points are the theories of Yang-Mills and Utiyama and, as a particular vantage point, the theory of Sciama and Kibble. Later, the Poincar\\'e gauge theory and its generalizations are explored and specific topi...
Matrix String Theory As A Generalized Quantum Theory
Minic, Djordje
1997-01-01
Matrix String Theory of Banks, Fischler, Shenker and Susskind can be understood as a generalized quantum theory (provisionally named "quansical" theory) which differs from Adler's generalized trace quantum dynamics. The effective Matrix String Theory Hamiltonian is constructed in a particular fermionic realization of Matrix String Theory treated as an example of "quansical" theory.
The theories on inequality: class theory
Directory of Open Access Journals (Sweden)
Ali Arslan
2006-11-01
Full Text Available This stduy aims to analyse class theory and its major expansions. In addition, the problems and dilemmas of class theory are discussed. Social inequality, either socially or economically, is one of the most common features of capitalist societies. Some people or some social groups have more money, more prestige, more privilege and more influence on the decision making process. Two main strategies have been used for analysing and explaining inequalities. The first and most popular strategy is “class theory” which stresses ownership and control to explain class differentiation. It concentrates on the inequalities based mainly on the ownership or non-ownership of economic resources. Class theory was fathered by Karl Marx and especially developed by Marxist writers. Class analysts focus on identification of classes as the major social forces of society. There are two main schools of thought in class theory with their variations within each school: a Marxist Class Theory, b Weberian Class Theory If the Marxist class analysis and Weberian class analysis are examined it will be seen that, two approaches are incompatible and it is impossible to synthesise them. Nevertheless, Hindess sees Weber’s view as the correction of and supplement to Marx’s ideas rather than an alternative. When the ideas of Marx and Weber are compared, it will be clearly seen that both Marx and Weber explain classes in relation to the economy. Nevertheless, while Marx defines classes in terms of the relations of production, Weber defines them in relation to the market.
Chung, Daniel J H
2016-01-01
We reformulate gauge theories in analogy with the vierbein formalism of general relativity. More specifically, we reformulate gauge theories such that their gauge dynamical degrees of freedom are local fields that transform linearly under the dual representation of the charged matter field. These local fields, which naively have the interpretation of non-local operators similar to Wilson lines, satisfy constraint equations. A set of basis tensor fields are used to solve these constraint equations, and their field theory is constructed. A new local symmetry in terms of the basis tensor fields is used to make this field theory local and maintain a Hamiltonian that is bounded from below. The field theory of the basis tensor fields is what we call the basis tensor gauge theory.
Linch, William D
2015-01-01
We consider, at the linearized level, the superspace formulation of lower-dimensional F-theory. In particular, we describe the embedding of 3D Type II supergravity of the superstring, or 4D, N=1 supergravity of M-theory, into the corresponding F-theory in full detail, giving the linearized action and gauge transformations in terms of the prepotential. This manifestly supersymmetric formulation reveals some features not evident from a component treatment, such as Weyl and local S-supersymmetry invariances. The linearized multiplet appears as a super 3-form (just as that for the manifestly T-dual theory is a super 2-form), reflecting the embedding of M-theory (as the T-dual theory embeds Type II supergravity). We also give the embedding of matter multiplets into this superspace, and derive the F-constraint from the gauge invariance of the gauge invariance.
DEFF Research Database (Denmark)
Zander, Pär Ola
2014-01-01
theory. The paper concludes that Baudrillard's arguments for abandoning Marxism altogether are problematic and led him away from developing a more finished theory of value. This is unfortunate because it remains a project that may yield interesting insights even in contemporary social theory, not least......Jean Baudrillard outlined a theory of value in his early writings that built on, but also criticized, Marxist concepts of use value and exchange value. In this paper, I use a close reading to delineate the diachronic transition of Baudrillard's writings toward anti-Marxism and (allegedly......) postmodernism, with specific focus on his value theory, in order to understand his own reasons for abandoning his previous position. I then follow the marginal stream of scholars who are making use of the early Baudrillard. I find his value theory promising but still a mere sketch rather than an actual general...
Algebraic quantum field theory
International Nuclear Information System (INIS)
The basic assumption that the complete information relevant for a relativistic, local quantum theory is contained in the net structure of the local observables of this theory results first of all in a concise formulation of the algebraic structure of the superselection theory and an intrinsic formulation of charge composition, charge conjugation and the statistics of an algebraic quantum field theory. In a next step, the locality of massive particles together with their spectral properties are wed for the formulation of a selection criterion which opens the access to the massive, non-abelian quantum gauge theories. The role of the electric charge as a superselection rule results in the introduction of charge classes which in term lead to a set of quantum states with optimum localization properties. Finally, the asymptotic observables of quantum electrodynamics are investigated within the framework of algebraic quantum field theory. (author)
DEFF Research Database (Denmark)
Javadi, Hossein; Forouzbakhsh, Farshid; Daei Kasmaei, Hamed
2016-01-01
is the mechanism of increasing in the photon energy that causes increase in its frequency growth? So, in CPH theory (Creative particles of Higgs Theory), it has been attempted to scrutinize the interface between classical mechanics, relativity and quantum mechanics through a novel approach to the established......There are various theories in physics, but nature is unique. This is not nature's problem that we have various theories; nature obeys simple and unique law. We should improve our theories. Universal constancy of the speed of light undergoes the question whether the limit on the light speed...... physical events. Emphasizing on these phenomena and presenting the relation between photon's energy and frequency, CPH Theory is to draw attention on the importance of constancy of speed in relation to the mass structure which will be scrutinized in reviewing relativistic Newton's second law. The results...
Thorbj, rn Knudsen
2002-01-01
The present article provides a minimal description of the causal structure of economic selection theory and outlines how the internal selection dynamics of business organisations can be reconciled with selection in competitive markets. In addition to generic similarity in terms of the Darwinian principles of variation, continuity and selection, it is argued that economic selection theory should mimic the causal structure of neo-Darwinian theory. Two of the most influential explanations of eco...
Vinokurov, Evgeny
2007-01-01
The manuscript represents a comprehensive theory of enclaves and exclaves. The theory comprises both political and economic aspects. It is the first general book on the world’s enclaves and exclaves. Due to its comprehensive and pioneer character, it has a potential to become a book of reference for the nascent and promising research field. In its attempt to provide a fully-fledged theory of enclaves and exclaves, it covers a wide scope of regions and territories throughout the world. Basical...
Tong, David
2009-01-01
This is a one semester course on bosonic string theory aimed at beginning graduate students. The lectures assume a working knowledge of quantum field theory and general relativity. Contents: 1. The Classical String 2. The Quantum String 3. Open Strings and D-Branes 4. Introducing Conformal Field Theory 5. The Polyakov Path Integral and Ghosts 6. String Interactions 7. The Low-Energy Effective Action 8. Compactification and T-Duality
Relevance Theory in Translation
Institute of Scientific and Technical Information of China (English)
Shao Jun; Jiang Min
2008-01-01
In perspective of relevance theory, translation is regarded as communication. According to relevance theory, communication not only requires encoding, transfer and decoding processes, but also involves inference in addition. As communication, translation decision-making is also based on the human beings' inferential mental faculty. Concentrating on relevance theory, this paper tries to analyze and explain some translation phenomena in two English versions of Cai Gen Tan-My Crude Philosophy of Life.
Accounting and Economic Theory
Martin Shubik
2003-01-01
This paper deals with the changing relationship between economic theory and accounting practice and theory. It argues that many of the basic problems encountered in practice cannot be avoided in any attempt to construct an economic theory adequate to handle dynamics. In particular problems of timing become critical. furthermore, there are several critical problems concerning profit maximization, the nature of the rate of interest, agency problems within the firm and the payment of dividends w...
Marx Boopathi
2012-01-01
The game theory techniques are used to find the equilibrium of a market. Game theory refers to the ways in which strategic interactions among economic agents produce outcomes with respect to the preferences (or utilities) of those agents, where the outcomes in question might have been intended by none of the agents. The oligopolistic market structures are taken and how game theory applies to them is explained.
International Nuclear Information System (INIS)
Some of the difficulties and limitations encountered when teaching neutron slowing down theory to nuclear engineering students, are examined. Specific problems in teaching the kinetics of the slowing down of neutrons, the neutron balance equation, resonance escape probabilities, and the continuous slowing down theory, are considered and it is suggested that, as far as possible, use should be made, by analogy, of the work already done with the students in deriving diffusion theory and its one group equation. (U.K.)
Theory Modeling and Simulation
Energy Technology Data Exchange (ETDEWEB)
Shlachter, Jack [Los Alamos National Laboratory
2012-08-23
Los Alamos has a long history in theory, modeling and simulation. We focus on multidisciplinary teams that tackle complex problems. Theory, modeling and simulation are tools to solve problems just like an NMR spectrometer, a gas chromatograph or an electron microscope. Problems should be used to define the theoretical tools needed and not the other way around. Best results occur when theory and experiments are working together in a team.
Hypergraph theory an introduction
Bretto, Alain
2013-01-01
This authored monograph presents hypergraph theory and covers both traditional elements of the theory as well as more original concepts such as entropy of hypergraph, similarities and kernels. Moreover, the author gives a detailed account to applications of the theory, including, but not limited to, applications for telecommunications and modeling of parallel data structures. The target audience primarily comprises researchers and practitioners in applied sciences but the book may also be beneficial for graduate students.
Supergravity for Effective Theories
Daniel Baumann; Daniel Green(Stanford Institute for Theoretical Physics, Stanford University, 382 Via Pueblo Mall, Stanford, CA 94305, U.S.A.)
2011-01-01
Higher-derivative operators are central elements of any effective field theory. In supersymmetric theories, these operators include terms with derivatives in the K\\"ahler potential. We develop a toolkit for coupling such supersymmetric effective field theories to supergravity. We explain how to write the action for minimal supergravity coupled to chiral superfields with arbitrary numbers of derivatives and curvature couplings. We discuss two examples in detail, showing how the component actio...
Supergravity from Gauge Theory
Berkowitz, Evan
2016-01-01
Gauge/gravity duality is the conjecture that string theories have dual descriptions as gauge theories. Weakly-coupled gravity is dual to strongly-coupled gauge theories, ideal for lattice calculations. I will show precision lattice calculations that confirm large-N continuum D0-brane quantum mechanics correctly reproduces the leading-order supergravity prediction for a black hole's internal energy---the first leading-order test of the duality---and constrains stringy corrections.
Chartrand, Gary
1984-01-01
Graph theory is used today in the physical sciences, social sciences, computer science, and other areas. Introductory Graph Theory presents a nontechnical introduction to this exciting field in a clear, lively, and informative style. Author Gary Chartrand covers the important elementary topics of graph theory and its applications. In addition, he presents a large variety of proofs designed to strengthen mathematical techniques and offers challenging opportunities to have fun with mathematics. Ten major topics - profusely illustrated - include: Mathematical Models, Elementary Concepts of Grap
DEFF Research Database (Denmark)
Rijkhoff, Jan
2010-01-01
This paper argues that grammatical theorizing and linguistic typologizing must go hand in hand and that rare typological features play a central role in the interaction of typology and theory. The paper is organized as follows. Section 2 discusses a sampling method that (compared to other sampling...... Functional (Discourse) Grammar and sections 4 and 5 are concerned with the crucial role of rara both in theory driven data collection and in data driven theory building....
Botond Koszegi
2014-01-01
This review provides a critical survey of psychology-and-economics ("behavioral-economics") research in contract theory. First, I introduce the theories of individual decision making most frequently used in behavioral contract theory, and formally illustrate some of their implications in contracting settings. Second, I provide a more comprehensive (but informal) survey of the psychology-and-economics work on classical contract-theoretic topics: moral hazard, screening, mechanism design, and i...
Ed Nosal; Peter Rupert
2002-01-01
It wasn’t A Beautiful Mind—the book or the movie—that made John Forbes Nash, Jr., famous. It was his work in game theory, a theory that models strategic interactions between people as games. Before Nash, the only games theorists could get a handle on were artificial ones with no real-world applications. Nash’s insights enabled economists to expand the use of game theory to interesting practical problems.
Introduction to superstring theory
Energy Technology Data Exchange (ETDEWEB)
Nunez, Carmen [Instituto de Astronomia y Fisica del Espacio, Buenos Aires (Argentina)], e-mail: carmen@iafe.uba.ar
2009-07-01
This is a very basic introduction to the AdS/CFT correspondence. The first lecture motivates the duality between gauge theories and gravity/string theories. The next two lectures introduce the bosonic and supersymmetric string theories. The fourth lecture is devoted to study Dp-branes and finally, in the fifth lecture I discuss the two worlds: N=4 SYM in 3+1 flat dimensions and type IIB superstrings in AdS{sub 5} x S5. (author)
Effective quantum field theories
International Nuclear Information System (INIS)
Certain dimensional parameters play a crucial role in the understanding of weak and strong interactions based on SU(2) x U(1) and SU(3) symmetry group theories and of grand unified theories (GUT's) based on SU(5). These parameters are the confinement scale of quantum chromodynamics and the breaking scales of SU(2) x U(1) and SU(5). The concepts of effective quantum field theories and renormalisability are discussed with reference to the economics and ethics of research. (U.K.)
Automated Lattice Perturbation Theory
Energy Technology Data Exchange (ETDEWEB)
Monahan, Christopher
2014-11-01
I review recent developments in automated lattice perturbation theory. Starting with an overview of lattice perturbation theory, I focus on the three automation packages currently "on the market": HiPPy/HPsrc, Pastor and PhySyCAl. I highlight some recent applications of these methods, particularly in B physics. In the final section I briefly discuss the related, but distinct, approach of numerical stochastic perturbation theory.
Gardner, JW
2003-01-01
Radical Theory of Rings distills the most noteworthy present-day theoretical topics, gives a unified account of the classical structure theorems for rings, and deepens understanding of key aspects of ring theory via ring and radical constructions. Assimilating radical theory's evolution in the decades since the last major work on rings and radicals was published, the authors deal with some distinctive features of the radical theory of nonassociative rings, associative rings with involution, and near-rings. Written in clear algebraic terms by globally acknowledged authorities, the presentation
Baird, J. K.
1986-01-01
The Ostwald-ripening theory is deduced and discussed starting from the fundamental principles such as Ising model concept, Mayer cluster expansion, Langer condensation point theory, Ginzburg-Landau free energy, Stillinger cutoff-pair potential, LSW-theory and MLSW-theory. Mathematical intricacies are reduced to an understanding version. Comparison of selected works, from 1949 to 1984, on solution of diffusion equation with and without sink/sources term(s) is presented. Kahlweit's 1980 work and Marqusee-Ross' 1954 work are more emphasized. Odijk and Lekkerkerker's 1985 work on rodlike macromolecules is introduced in order to simulate interested investigators.
Cappell, Sylvain; Rosenberg, Jonathan
2014-01-01
Surgery theory, the basis for the classification theory of manifolds, is now about forty years old. There have been some extraordinary accomplishments in that time, which have led to enormously varied interactions with algebra, analysis, and geometry. Workers in many of these areas have often lamented the lack of a single source that surveys surgery theory and its applications. Indeed, no one person could write such a survey. The sixtieth birthday of C. T. C. Wall, one of the leaders of the founding generation of surgery theory, provided an opportunity to rectify the situation and produce a
Cappell, Sylvain; Rosenberg, Jonathan
2014-01-01
Surgery theory, the basis for the classification theory of manifolds, is now about forty years old. The sixtieth birthday (on December 14, 1996) of C.T.C. Wall, a leading member of the subject''s founding generation, led the editors of this volume to reflect on the extraordinary accomplishments of surgery theory as well as its current enormously varied interactions with algebra, analysis, and geometry. Workers in many of these areas have often lamented the lack of a single source surveying surgery theory and its applications. Because no one person could write such a survey, the editors ask
Enderton, Herbert B
1977-01-01
This is an introductory undergraduate textbook in set theory. In mathematics these days, essentially everything is a set. Some knowledge of set theory is necessary part of the background everyone needs for further study of mathematics. It is also possible to study set theory for its own interest--it is a subject with intruiging results anout simple objects. This book starts with material that nobody can do without. There is no end to what can be learned of set theory, but here is a beginning.
DEFF Research Database (Denmark)
Schlamovitz, Jesper
2015-01-01
Process thinking and process-based theory are receiving increased attention in the field of organization studies and organization theory development (Tsoukas & Chia, 2002; Langley & Tsoukas, 2010; Hernes, 2014). The aim has been to study processes rather than structures, in organizations. This has...... recently inspired research on the organizing of projects and the development of a (new) theory of temporary organizations (Bakker, 2010; Blomquist et al. 2010; Söderlund, 2013). These theories are still under development and need empirical studies that can show their relevance for practice. This paper...
Generalized etale cohomology theories
Jardine, John F
1997-01-01
A generalized etale cohomology theory is a theory which is represented by a presheaf of spectra on an etale site for an algebraic variety, in analogy with the way an ordinary spectrum represents a cohomology theory for spaces. Examples include etale cohomology and etale K-theory. This book gives new and complete proofs of both Thomason's descent theorem for Bott periodic K-theory and the Nisnevich descent theorem. In doing so, it exposes most of the major ideas of the homotopy theory of presheaves of spectra, and generalized etale homology theories in particular. The treatment includes, for the purpose of adequately dealing with cup product structures, a development of stable homotopy theory for n-fold spectra, which is then promoted to the level of presheaves of n-fold spectra. This book should be of interest to all researchers working in fields related to algebraic K-theory. The techniques presented here are essentially combinatorial, and hence algebraic. An extensive background in traditional stable hom...
Empirical comparison of theories
International Nuclear Information System (INIS)
The book represents the first, comprehensive attempt to take an empirical approach for comparative assessment of theories in sociology. The aims, problems, and advantages of the empirical approach are discussed in detail, and the three theories selected for the purpose of this work are explained. Their comparative assessment is performed within the framework of several research projects, which among other subjects also investigate the social aspects of the protest against nuclear power plants. The theories analysed in this context are the theory of mental incongruities and that of the benefit, and their efficiency in explaining protest behaviour is compared. (orig./HSCH)
MALFLIET, R
1993-01-01
We discuss the present status of relativistic transport theory. Special emphasis is put on problems of topical interest: hadronic features, thermodynamical consistent approximations and spectral properties.
Crisan, Mircea
1989-01-01
This book discusses the most important aspects of the theory. The phenomenological model is followed by the microscopic theory of superconductivity, in which modern formalism of the many-body theory is used to treat most important problems such as superconducting alloys, coexistence of superconductivity with the magnetic order, and superconductivity in quasi-one-dimensional systems. It concludes with a discussion on models for exotic and high temperature superconductivity. Its main aim is to review, as complete as possible, the theory of superconductivity from classical models and methods up t
Games, theory and applications
Thomas, L C
2011-01-01
Anyone with a knowledge of basic mathematics will find this an accessible and informative introduction to game theory. It opens with the theory of two-person zero-sum games, two-person non-zero sum games, and n-person games, at a level between nonmathematical introductory books and technical mathematical game theory books. Succeeding sections focus on a variety of applications - including introductory explanations of gaming and meta games - that offer nonspecialists information about new areas of game theory at a comprehensible level. Numerous exercises appear with full solutions, in addition
International Nuclear Information System (INIS)
The formation mechanism and plasma theory of tornado are proposed. Tornado is considered as a gas discharge. Electrical fields, currents, electromagnetic forces and velocities fields have been obtained
Dwivedi, Yogesh K; Schneberger, Scott L
2011-01-01
The overall mission of this book is to provide a comprehensive understanding and coverage of the various theories and models used in IS research. Specifically, it aims to focus on the following key objectives: To describe the various theories and models applicable to studying IS/IT management issues. To outline and describe, for each of the various theories and models, independent and dependent constructs, reference discipline/originating area, originating author(s), seminal articles, level of analysis (i.e. firm, individual, industry) and links with other theories. To provide a critical revie
Mandl, Franz
2010-01-01
Following on from the successful first (1984) and revised (1993) editions, this extended and revised text is designed as a short and simple introduction to quantum field theory for final year physics students and for postgraduate students beginning research in theoretical and experimental particle physics. The three main objectives of the book are to: Explain the basic physics and formalism of quantum field theory To make the reader proficient in theory calculations using Feynman diagrams To introduce the reader to gauge theories, which play a central role in elementary particle physic
DEFF Research Database (Denmark)
Balle, Søren Hattesen
2009-01-01
This paper takes its starting point in a short poem by Wallace Stevens from 1917, which incidentally bears the title “Theory”. The poem can be read as a parable of theory, i.e., as something literally ’thrown beside’ theory (cf. OED: “< ancient Greek: parabole: a placing side by side“). In the ph......, so theory needs its stylistic features to rule the world. And Stevens’s poem is a good example of how theory is at the hands of literature for gaining power through style....
Young, Petyon
2014-01-01
The ability to understand and predict behavior in strategic situations, in which an individual's success in making choices depends on the choices of others, has been the domain of game theory since the 1950s. Developing the theories at the heart of game theory has resulted in 8 Nobel Prizes and insights that researchers in many fields continue to develop. In Volume 4, top scholars synthesize and analyze mainstream scholarship on games and economic behavior, providing an updated account of developments in game theory since the 2002 publication of Volume 3, which only covers work through the mi
DEFF Research Database (Denmark)
Hastings, Gerard; Brown, Abraham; Anker, Thomas Boysen
2010-01-01
The chapter looks at three important theories which help social marketers to think more systematically about the key questions they need to address: (i) how does the target group or population feel about a particular behaviour (Stages of Change Theory); (ii) what social and contextual factors...... influence this positioning (Social Cognitive Theory and Social Norms) and; (iii) what offerings might encourage them to change their behaviour – or, those in a position to do so, to make the social context more conducive to change (Exchange Theory). Moreover, the chapter outlines how social marketers might...
Goethe, Johann Wolfgang von
2006-01-01
The wavelength theory of light and color had been firmly established by the time the great German poet published his Theory of Colours in 1810. Nevertheless, Goethe believed that the theory derived from a fundamental error, in which an incidental result was mistaken for a elemental principle. Far from affecting a knowledge of physics, he maintained that such a background would inhibit understanding. The conclusions Goethe draws here rest entirely upon his personal observations.This volume does not have to be studied to be appreciated. The author's subjective theory of colors permits him to spe
Kontextualisierung von Queer Theory Contextualizing Queer Theory
Directory of Open Access Journals (Sweden)
Anna Voigt
2008-03-01
Full Text Available Christine M. Klapeer legt in diesem Einführungsband dar, aus welchen politischen und theoretischen Kontexten heraus sich ‚queer‘ zu einem Begriff mit besonderem politischem und theoretischem Gehalt entwickelt hat. Wesentlich zielt sie dabei auf eine kritische Kontextualisierung von „queer theory”. Die Autorin geht zunächst auf das Gay Liberation Movement ein, grenzt die Queer Theory vom Poststrukturalismus, von feministischen Theorien und den Lesbian and Gay Studies ab, beleuchtet Eckpunkte queeren Denkens und zeichnet schließlich die Entwicklungen in Österreich sowohl politisch-rechtlich als auch bewegungsgeschichtlich und in der Wissenschaftslandschaft nach.Christine M. Klapeer’s introductory volume demonstrates the manner in which ‘queer’ grew out of various political and theoretical contexts to become a term with special political and theoretical content. She focuses primarily on a critical contextualization of “queer theory.” The author begins by approaching the Gay Liberation Movement and then distinguishes Queer Theory from poststructuralism, from feminist theories, and from Lesbian and Gay Studies. She continues on to illuminate the key aspects of queer thought and concludes by sketching the development in Austria in terms of politics and the law, the history of movements, and within the landscape of knowledge.
[Topics in field theory and string theory
International Nuclear Information System (INIS)
In the past year, I have continued to investigate the relations between conformal field theories and lattice statistical mechanical models, and in particular have been studying two dimensional models coupled to quantum gravity. I have continued as well to consider possible extension of these results to higher dimensions and potential applications in other contexts
Dynasting Theory: Lessons in learning grounded theory
Directory of Open Access Journals (Sweden)
Johnben Teik-Cheok Loy, MBA, MTS, Ph.D.
2011-06-01
Full Text Available This article captures the key learning lessons gleaned from the author’s experience learning and developing a grounded theory for his doctoral dissertation using the classic methodology as conceived by Barney Glaser. The theory was developed through data gathered on founders and successors of Malaysian Chinese family-own businesses. The main concern for Malaysian Chinese family businesses emerged as dynasting . the building, maintaining, and growing the power and resources of the business within the family lineage. The core category emerged as dynasting across cultures, where founders and successors struggle to transition from traditional Chinese to hybrid cultural and modernized forms of family business from one generation to the next. The key learning lessons were categorized under five headings: (a sorting through different versions of grounded theory, (b educating and managing research stakeholders, (c embracing experiential learning, (d discovering the core category: grounded intuition, and (e recognizing limitations and possibilities.Keywords: grounded theory, learning, dynasting, family business, Chinese
Rowe, D. J.; McCoy, A. E.; Caprio, M. A.
2016-03-01
The nuclear collective models introduced by Bohr, Mottelson and Rainwater, together with the Mayer-Jensen shell model, have provided the central framework for the development of nuclear physics. This paper reviews the microscopic evolution of the collective models and their underlying foundations. In particular, it is shown that the Bohr-Mottelson models have expressions as macroscopic limits of microscopic models that have precisely defined expressions in many-nucleon quantum mechanics. Understanding collective models in this way is especially useful because it enables the analysis of nuclear properties in terms of them to be revisited and reassessed in the light of their microscopic foundations.
String Theory and Gauge Theories (Strings, Gravity, and the Large N Limit of Gauge Theories)
International Nuclear Information System (INIS)
We will see how gauge theories, in the limit that the number of colors is large, give string theories. We will discuss some examples of particular gauge theories where the corresponding string theory is known precisely, starting with the case of the maximally supersymmetric theory in four dimensions which corresponds to ten dimensional string theory. We will discuss recent developments in this area.
Mayer, William V.
In this paper the author examines the question of whether evolution is a theory or a dogma. He refutes the contention that there is a monolithic scientific conspiracy to present evolution as dogma and suggests that his own presentation might be more appropriately entitled "Creationism: Theory or Dogma." (PEB)
DEFF Research Database (Denmark)
Wæver, Ole
2011-01-01
distinct from both the study of political practices of securitization and explorations of competing concepts of politics among security theories. It means tracking what kinds of analysis the theory can produce and whether such analysis systematically impacts real-life political struggles. Securitization...
Suppes, Patrick
1972-01-01
This clear and well-developed approach to axiomatic set theory is geared toward upper-level undergraduates and graduate students. It examines the basic paradoxes and history of set theory and advanced topics such as relations and functions, equipollence, finite sets and cardinal numbers, rational and real numbers, and other subjects. 1960 edition.
Rexhepi, Jevdet; Torres, Carlos Alberto
2011-01-01
This paper discusses Critical Theory, a model of theorizing in the field of the political sociology of education. We argue for a "reimagined" Critical Theory to herald an empowering, liberatory education that fosters curiosity and critical thinking, and a means for successful bottom-up, top-down political engagement. We present arguments at a…
Evaluating Conceptual Metaphor Theory
Gibbs, Raymond W., Jr.
2011-01-01
A major revolution in the study of metaphor occurred 30 years ago with the introduction of "conceptual metaphor theory" (CMT). Unlike previous theories of metaphor and metaphorical meaning, CMT proposed that metaphor is not just an aspect of language, but a fundamental part of human thought. Indeed, most metaphorical language arises from…
2003-01-01
With the start of next year, CERN's Theory Division and Experimental Physics Division will merge to form the new Department of Physics. The Bulletin looks back at an era, has a closer a look at what the Theory Division is and what makes it so special.
Shor, Mikhael
2003-01-01
States making game theory relevant and accessible to students is challenging. Describes the primary goal of GameTheory.net is to provide interactive teaching tools. Indicates the site strives to unite educators from economics, political and computer science, and ecology by providing a repository of lecture notes and tests for courses using…
DEFF Research Database (Denmark)
Michelsen, Aage U.
2004-01-01
Tankegangen bag Theory of Constraints samt planlægningsprincippet Drum-Buffer-Rope. Endvidere skitse af The Thinking Process.......Tankegangen bag Theory of Constraints samt planlægningsprincippet Drum-Buffer-Rope. Endvidere skitse af The Thinking Process....
Rewriting the Opportunity Theory
DEFF Research Database (Denmark)
Korsgaard, Steffen T.
The aim of this paper is to further the discussion of opportunity theory by discussing its ontological and epistemological underpinnings, which have been neglected in previous discussions. The idea that opportunities have an objective component is critically examined drawing on insights from social...... constructionism. It is argued that opportunity theory needs to be rewritten....
International Nuclear Information System (INIS)
This report briefly discussion the following programs of the Institute for Nuclear Theory: fundamental interactions in nuclei; strangeness in hadrons and nuclei; microscopic nuclear structure theory; nuclear physics in atoms and molecules; phenomenology and lattice QCD; and large amplitude collective motion
Jaeger, Audrey J.; Dunstan, Stephany; Thornton, Courtney; Rockenbach, Alyssa B.; Gayles, Joy G.; Haley, Karen J.
2013-01-01
When making decisions that impact student learning, college educators often consider previous experiences, precedent, common sense, and advice from colleagues. But how often do they consider theory? At a recent state-level educators' meeting, the authors of this article asked 50 student affairs educators about the use of theory in their practice.…
Multisource Algorithmic Information Theory
Shen, Alexander
2006-01-01
Multisource information theory is well known in Shannon setting. It studies the possibilities of information transfer through a network with limited capacities. Similar questions could be studied for algorithmic information theory and provide a framework for several known results and interesting questions.
Molder, te H.F.M.
2009-01-01
Available in both print and electronic formats, the Encyclopedia of Communication Theory provides students and researchers with a comprehensive two-volume overview of contemporary communication theory. Reference librarians report that students frequently approach them seeking a source that will prov
Science and information theory
Brillouin, Leon
2013-01-01
A classic source for exploring the connections between information theory and physics, this text is geared toward upper-level undergraduates and graduate students. The author, a giant of 20th-century mathematics, applies the principles of information theory to a variety of issues, including Maxwell's demon, thermodynamics, and measurement problems. 1962 edition.
Towards Extended Vantage Theory
Glaz, Adam
2010-01-01
The applicability of Vantage Theory (VT), a model of (colour) categorization, to linguistic data largely depends on the modifications and adaptations of the model for the purpose. An attempt to do so proposed here, called Extended Vantage Theory (EVT), slightly reformulates the VT conception of vantage by capitalizing on some of the entailments of…
Energy Technology Data Exchange (ETDEWEB)
Catterall, Simon [Syracuse University; Hubisz, Jay [Syracuse University; Balachandran, Aiyalam [Syracuse University; Schechter, Joe [Syracuse University
2013-01-05
This final report describes the activities of the high energy theory group at Syracuse University for the period 1 January 2010 through April 30 2013. The research conducted by the group includes lattice gauge theory, non-commutative geometry, phenomenology and mathematical physics.
DEFF Research Database (Denmark)
Pais, Alexandre; Valero, Paola
2014-01-01
What is the place of social theory in mathematics education research, and what is it for? This special issue of Educational Studies in Mathematics offers insights on what could be the role of some sociological theories in a field that has historically privileged learning theories coming from...... from a “socio-cultural” approach to learning and rather deploy sociological theories in the analysis of mathematics education practices. In this commentary paper, we will point to what we see to be the contributions of these papers to the field. We will do so by highlighting issues that run through...... the six papers. We will try to synthetize what we think are the benchmarks of the social approach to mathematics education that they propose. We will also take a critical stance and indicate some possible extensions of the use of social theory that are not addressed in this special issue but nonetheless...
Statistical theory and inference
Olive, David J
2014-01-01
This text is for a one semester graduate course in statistical theory and covers minimal and complete sufficient statistics, maximum likelihood estimators, method of moments, bias and mean square error, uniform minimum variance estimators and the Cramer-Rao lower bound, an introduction to large sample theory, likelihood ratio tests and uniformly most powerful tests and the Neyman Pearson Lemma. A major goal of this text is to make these topics much more accessible to students by using the theory of exponential families. Exponential families, indicator functions and the support of the distribution are used throughout the text to simplify the theory. More than 50 ``brand name" distributions are used to illustrate the theory with many examples of exponential families, maximum likelihood estimators and uniformly minimum variance unbiased estimators. There are many homework problems with over 30 pages of solutions.
Pachner, J.
1984-11-01
In order to make reliable predictions in any region of human activity, it is necessary to distinguish clearly what is based on experience and what is a construction of intellect. The theory of knowledge developed in the present paper is an attempt to devise a set of axioms that demarcate experience, as the only source of our knowledge of the external world, from the ideas, scientific models, and theories by means of which the scientific predictions are made. After a discussion of the causality in relation to the laws of nature, the axioms of the expounded theory are formulated in the formalism of set theory. The theory is then applied to some problems in physics to demonstrate its usefulness.
Theory of gravitational interactions
Gasperini, Maurizio
2013-01-01
This reference textbook is an up-to-date and self-contained introduction to the theory of gravitational interactions. The first part of the book follows the traditional presentation of general relativity as a geometric theory of the macroscopic gravitational field. A second, advanced part then discusses the deep analogies (and differences) between a geometric theory of gravity and the gauge theories of the other fundamental interactions. This fills a gap which is present in the context of the traditional approach to general relativity, and which usually makes students puzzled about the role of gravity. The necessary notions of differential geometry are reduced to the minimum, leaving more room for those aspects of gravitational physics of current phenomenological and theoretical interest, such as the properties of gravitational waves, the gravitational interactions of spinors, and the supersymmetric and higher-dimensional generalization of the Einstein equations. Theory of Gravitational Interactions will be o...
DEFF Research Database (Denmark)
Birkedal, Lars; Bizjak, Aleš; Clouston, Ranald;
2016-01-01
types. This further expands the foundations of CTT as a basis for formalisation in mathematics and computer science. We present examples to demonstrate the expressivity of our type theory, all of which have been checked using a prototype type-checker implementation, and present semantics in a presheaf......This paper improves the treatment of equality in guarded dependent type theory (GDTT), by combining it with cubical type theory (CTT). GDTT is an extensional type theory with guarded recursive types, which are useful for building models of program logics, and for programming and reasoning with...... coinductive types. We wish to implement GDTT with decidable type-checking, while still supporting non-trivial equality proofs that reason about the extensions of guarded recursive constructions. CTT is a variation of Martin-L\\"of type theory in which the identity type is replaced by abstract paths between...
Bergshoeff, Eric A; Penas, Victor A; Riccioni, Fabio
2016-01-01
We present the dual formulation of double field theory at the linearized level. This is a classically equivalent theory describing the duals of the dilaton, the Kalb-Ramond field and the graviton in a T-duality or O(D,D) covariant way. In agreement with previous proposals, the resulting theory encodes fields in mixed Young-tableau representations, combining them into an antisymmetric 4-tensor under O(D,D). In contrast to previous proposals, the theory also requires an antisymmetric 2-tensor and a singlet, which are not all pure gauge. The need for these additional fields is analogous to a similar phenomenon for "exotic" dualizations, and we clarify this by comparing with the dualizations of the component fields. We close with some speculative remarks on the significance of these observations for the full non-linear theory yet to be constructed.
Lipstein, Arthur E
2014-01-01
We formulate the theory of a 2-form gauge field on a Euclidean spacetime lattice. In this approach, the fundamental degrees of freedom live on the faces of the lattice, and the action can be constructed from the sum over Wilson surfaces associated with each fundamental cube of the lattice. If we take the gauge group to be $U(1)$, the theory reduces to the well-known abelian gerbe theory in the continuum limit. We also propose a very simple and natural non-abelian generalization with gauge group $U(N) \\times U(N)$, which gives rise to $U(N)$ Yang-Mills theory upon dimensional reduction. Formulating the theory on a lattice has several other advantages. In particular, it is possible to compute many observables, such as the expectation value of Wilson surfaces, analytically at strong coupling and numerically for any value of the coupling.
Quantal density functional theory
Sahni, Viraht
2016-01-01
This book deals with quantal density functional theory (QDFT) which is a time-dependent local effective potential theory of the electronic structure of matter. The treated time-independent QDFT constitutes a special case. In the 2nd edition, the theory is extended to include the presence of external magnetostatic fields. The theory is a description of matter based on the ‘quantal Newtonian’ first and second laws which is in terms of “classical” fields that pervade all space, and their quantal sources. The fields, which are explicitly defined, are separately representative of electron correlations due to the Pauli exclusion principle, Coulomb repulsion, correlation-kinetic, correlation-current-density, and correlation-magnetic effects. The book further describes Schrödinger theory from the new physical perspective of fields and quantal sources. It also describes traditional Hohenberg-Kohn-Sham DFT, and explains via QDFT the physics underlying the various energy functionals and functional derivatives o...
Theory X and Theory Y in the Organizational Structure.
Barry, Thomas J.
This document defines contrasting assumptions about the labor force--theory X and theory Y--and shows how they apply to the pyramid organizational structure, examines the assumptions of the two theories, and finally, based on a survey and individual interviews, proposes a merger of theories X and Y to produce theory Z. Organizational structures…
String theory as a higher spin theory
Gaberdiel, Matthias R.; Gopakumar, Rajesh
2016-09-01
The symmetries of string theory on {AdS}_3× {S}^3× T^4 at the dual of the symmetric product orbifold point are described by a so-called Higher Spin Square (HSS). We show that the massive string spectrum in this background organises itself in terms of representations of this HSS, just as the matter in a conventional higher spin theory does so in terms of representations of the higher spin algebra. In particular, the entire untwisted sector of the orbifold can be viewed as the Fock space built out of the multiparticle states of a single representation of the HSS, the so-called `minimal' representation. The states in the twisted sector can be described in terms of tensor products of a novel family of representations that are somewhat larger than the minimal one.
Field-theory methods in coagulation theory
International Nuclear Information System (INIS)
Coagulating systems are systems of chaotically moving particles that collide and coalesce, producing daughter particles of mass equal to the sum of the masses involved in the respective collision event. The present article puts forth basic ideas underlying the application of methods of quantum-field theory to the theory of coagulating systems. Instead of the generally accepted treatment based on the use of a standard kinetic equation that describes the time evolution of concentrations of particles consisting of a preset number of identical objects (monomers in the following), one introduces the probability W(Q, t) to find the system in some state Q at an instant t for a specific rate of transitions between various states. Each state Q is characterized by a set of occupation numbers Q = (n1, n2, ..., ng, ...), where ng is the total number of particles containing precisely g monomers. Thereupon, one introduces the generating functional Ψ for the probability W(Q, t). The time evolution of Ψ is described by an equation that is similar to the Schrödinger equation for a one-dimensional Bose field. This equation is solved exactly for transition rates proportional to the product of the masses of colliding particles. It is shown that, within a finite time interval, which is independent of the total mass of the entire system, a giant particle of mass about the mass of the entire system may appear in this system. The particle in question is unobservable in the thermodynamic limit, and this explains the well-known paradox of mass-concentration nonconservation in classical kinetic theory. The theory described in the present article is successfully applied in studying the time evolution of random graphs.
Higher Gauge Theory and M-Theory
Palmer, Sam
2014-01-01
In this thesis, the emerging field of higher gauge theory will be discussed, particularly in relation to problems arising in M-theory, such as selfdual strings and the so-called (2,0) theory. This thesis will begin with a Nahm-like construction for selfdual strings using loop space, the space of loops on spacetime. This construction maps solutions of the Basu-Harvey equation, the BPS equation arising in the description of multiple M2-branes, to solutions of a selfdual string equation on loop space. Furthermore, all ingredients of the construction reduce to those of the ordinary Nahm construction when compactified on a circle with all loops restricted to those wrapping the circle. The rest of this thesis, however, will not involve loop space. We will see a Nahm-like construction for the case of infinitely many selfdual strings, suspended between two M5-branes. This is possible since the limit taken renders the fields describing the M5-branes abelian. This avoids the problem which the rest of this thesis focuse...
Energy Technology Data Exchange (ETDEWEB)
Svozil, K. [Univ. of Technology, Vienna (Austria)
1995-11-01
Inasmuch as physical theories are formalizable, set theory provides a framework for theoretical physics. Four speculations about the relevance of set theoretical modeling for physics are presented: the role of transcendental set theory (i) in chaos theory, (ii) for paradoxical decompositions of solid three-dimensional objects, (iii) in the theory of effective computability (Church-Turing thesis) related to the possible {open_quotes}solution of supertasks,{close_quotes} and (iv) for weak solutions. Several approaches to set theory and their advantages and disadvantages for physical applications are discussed: Cantorian {open_quotes}naive{close_quotes} (i.e., nonaxiomatic) set theory, contructivism, and operationalism. In the author`s opinion, an attitude, of {open_quotes}suspended attention{close_quotes} (a term borrowed from psychoanalysis) seems most promising for progress. Physical and set theoretical entities must be operationalized wherever possible. At the same time, physicists should be open to {open_quotes}bizarre{close_quotes} or {open_quotes}mindboggling{close_quotes} new formalisms, which need not be operationalizable or testable at the time of their creation, but which may successfully lead to novel fields of phenomenology and technology.
Bollobás, Béla
1998-01-01
The time has now come when graph theory should be part of the education of every serious student of mathematics and computer science, both for its own sake and to enhance the appreciation of mathematics as a whole. This book is an in-depth account of graph theory, written with such a student in mind; it reflects the current state of the subject and emphasizes connections with other branches of pure mathematics. The volume grew out of the author's earlier book, Graph Theory -- An Introductory Course, but its length is well over twice that of its predecessor, allowing it to reveal many exciting new developments in the subject. Recognizing that graph theory is one of several courses competing for the attention of a student, the book contains extensive descriptive passages designed to convey the flavor of the subject and to arouse interest. In addition to a modern treatment of the classical areas of graph theory such as coloring, matching, extremal theory, and algebraic graph theory, the book presents a detailed ...
Finite temperature field theory
Das, Ashok
1997-01-01
This book discusses all three formalisms used in the study of finite temperature field theory, namely the imaginary time formalism, the closed time formalism and thermofield dynamics. Applications of the formalisms are worked out in detail. Gauge field theories and symmetry restoration at finite temperature are among the practical examples discussed in depth. The question of gauge dependence of the effective potential and the Nielsen identities are explained. The nonrestoration of some symmetries at high temperature (such as supersymmetry) and theories on nonsimply connected space-times are al
Theories of information behavior
Erdelez, Sandra; McKechnie, Lynne
2005-01-01
This unique book presents authoritative overviews of more than 70 conceptual frameworks for understanding how people seek, manage, share, and use information in different contexts. A practical and readable reference to both well-established and newly proposed theories of information behavior, the book includes contributions from 85 scholars from 10 countries. Each theory description covers origins, propositions, methodological implications, usage, links to related conceptual frameworks, and listings of authoritative primary and secondary references. The introductory chapters explain key concepts, theory–method connections, and the process of theory development.
Theory of intermolecular forces
Margenau, H; Ter Haar, D
1971-01-01
Theory of Intermolecular Forces deals with the exposition of the principles and techniques of the theory of intermolecular forces. The text focuses on the basic theory and surveys other aspects, with particular attention to relevant experiments. The initial chapters introduce the reader to the history of intermolecular forces. Succeeding chapters present topics on short, intermediate, and long range atomic interactions; properties of Coulomb interactions; shape-dependent forces between molecules; and physical adsorption. The book will be of good use to experts and students of quantum mechanics
Hansen, Jean-Pierre
1986-01-01
This book gives a comprehensive and up-to-date treatment of the theory of ""simple"" liquids. The new second edition has been rearranged and considerably expanded to give a balanced account both of basic theory and of the advances of the past decade. It presents the main ideas of modern liquid state theory in a way that is both pedagogical and self-contained. The book should be accessible to graduate students and research workers, both experimentalists and theorists, who have a good background in elementary mechanics.Key Features* Compares theoretical deductions with experimental r
Fraïssé, R
2011-01-01
The first part of this book concerns the present state of the theory of chains (= total or linear orderings), in connection with some refinements of Ramsey's theorem, due to Galvin and Nash-Williams. This leads to the fundamental Laver's embeddability theorem for scattered chains, using Nash-Williams' better quasi-orderings, barriers and forerunning.The second part (chapters 9 to 12) extends to general relations the main notions and results from order-type theory. An important connection appears with permutation theory (Cameron, Pouzet, Livingstone and Wagner) and with logics (existence criter
DEFF Research Database (Denmark)
Dindler, Christian; Dalsgaard, Peter
2014-01-01
We present the notion of ‘bridging concepts’ as a particular form of intermediary knowledge in HCI research, residing between theory and practice. We argue that bridging concepts address the challenge of facilitating exchange between theory and practice in HCI, and we compare it to other....... These constituents specify how bridging concepts, as a form of knowledge, are accountable to both theory and practice. We present an analysis of the concept of ‘peepholes’ as an example of a bridging concept aimed at spurring user curiosity and engagement....
Quantum electronics basic theory
Fain, V M; Sanders, J H
1969-01-01
Quantum Electronics, Volume 1: Basic Theory is a condensed and generalized description of the many research and rapid progress done on the subject. It is translated from the Russian language. The volume describes the basic theory of quantum electronics, and shows how the concepts and equations followed in quantum electronics arise from the basic principles of theoretical physics. The book then briefly discusses the interaction of an electromagnetic field with matter. The text also covers the quantum theory of relaxation process when a quantum system approaches an equilibrium state, and explai
Superstring perturbation theory
Adam, I.
2009-01-01
The state of superstring perturbation theory is reviewed with an emphasis on the state of the pure spinor superstring perturbation theory. We begin with a brief summary of the state of perturbation theory in the Ramond–Neveu–Schwarz and in the Green–Schwarz formulations of the superstring. Then we proceed to a quick review of the minimal and non-minimal pure spinor formulations of the superstring and discuss the multi-loop amplitude prescriptions in each of them. We end with a summary and ope...
Eves, Howard
1980-01-01
The usefulness of matrix theory as a tool in disciplines ranging from quantum mechanics to psychometrics is widely recognized, and courses in matrix theory are increasingly a standard part of the undergraduate curriculum.This outstanding text offers an unusual introduction to matrix theory at the undergraduate level. Unlike most texts dealing with the topic, which tend to remain on an abstract level, Dr. Eves' book employs a concrete elementary approach, avoiding abstraction until the final chapter. This practical method renders the text especially accessible to students of physics, engineeri
Cohn, Harvey
1980-01-01
""A very stimulating book ... in a class by itself."" - American Mathematical MonthlyAdvanced students, mathematicians and number theorists will welcome this stimulating treatment of advanced number theory, which approaches the complex topic of algebraic number theory from a historical standpoint, taking pains to show the reader how concepts, definitions and theories have evolved during the last two centuries. Moreover, the book abounds with numerical examples and more concrete, specific theorems than are found in most contemporary treatments of the subject.The book is divided into three parts
Menasco, William
2005-01-01
This book is a survey of current topics in the mathematical theory of knots. For a mathematician, a knot is a closed loop in 3-dimensional space: imagine knotting an extension cord and then closing it up by inserting its plug into its outlet. Knot theory is of central importance in pure and applied mathematics, as it stands at a crossroads of topology, combinatorics, algebra, mathematical physics and biochemistry.* Survey of mathematical knot theory* Articles by leading world authorities* Clear exposition, not over-technical* Accessible to readers with undergraduate background in mathematics
DEFF Research Database (Denmark)
Knudsen, Thorbjørn
2003-01-01
The present article provides a minimal description of the causal structure of economic selection theory and outlines how the internal selection dynamics of business organisations can be reconciled with selection in competitive markets. In addition to generic similarity in terms of the Darwinian...... principles of variation, continuity and selection, it is argued that economic selection theory should mimic the causal structure of neo-Darwinian theory. Two of the most influential explanations of economic evolution, Alchian's and Nelson and Winter's, are used to illustrate how this could be achieved....
Irreversible processes kinetic theory
Brush, Stephen G
2013-01-01
Kinetic Theory, Volume 2: Irreversible Processes deals with the kinetic theory of gases and the irreversible processes they undergo. It includes the two papers by James Clerk Maxwell and Ludwig Boltzmann in which the basic equations for transport processes in gases are formulated, together with the first derivation of Boltzmann's ""H-theorem"" and a discussion of this theorem, along with the problem of irreversibility.Comprised of 10 chapters, this volume begins with an introduction to the fundamental nature of heat and of gases, along with Boltzmann's work on the kinetic theory of gases and s
Gross, Jonathan L; Zhang, Ping
2013-01-01
In the ten years since the publication of the best-selling first edition, more than 1,000 graph theory papers have been published each year. Reflecting these advances, Handbook of Graph Theory, Second Edition provides comprehensive coverage of the main topics in pure and applied graph theory. This second edition-over 400 pages longer than its predecessor-incorporates 14 new sections. Each chapter includes lists of essential definitions and facts, accompanied by examples, tables, remarks, and, in some cases, conjectures and open problems. A bibliography at the end of each chapter provides an ex
On Nietzsche's "Superman" Theory
Institute of Scientific and Technical Information of China (English)
董晓烨; 吴晓意
2016-01-01
Nietzsche, German philosopher, who has had a great influence on the transformation of western philosophy from the contemporary to the modern, is a non-rationalist. Since the birth of Nietzsche's philosophy, evaluation from the international academic circles on his thoughts has been mixed. The"Superman" philosophy is an important part of Nietzsche's theory. He believes the spirit of strong will and that the development of man is endless, finally, we will have a"Superman". This theory has broken the tradition of western rationalism, the moral tradition of Christianity and the cultural tradition of the enlightenment since Socrates. However, we should evaluate the"Superman" theory properly.
Georgiev, Svetlin G
2015-01-01
This book explains many fundamental ideas on the theory of distributions. The theory of partial differential equations is one of the synthetic branches of analysis that combines ideas and methods from different fields of mathematics, ranging from functional analysis and harmonic analysis to differential geometry and topology. This presents specific difficulties to those studying this field. This book, which consists of 10 chapters, is suitable for upper undergraduate/graduate students and mathematicians seeking an accessible introduction to some aspects of the theory of distributions. It can also be used for one-semester course.
Generalized Supersymmetric Perturbation Theory
Institute of Scientific and Technical Information of China (English)
B. G(o)n(ǖ)l
2004-01-01
@@ Using the basic ingredient of supersymmetry, a simple alternative approach is developed to perturbation theory in one-dimensional non-relativistic quantum mechanics. The formulae for the energy shifts and wavefunctions do not involve tedious calculations which appear in the available perturbation theories. The model applicable in the same form to both the ground state and excited bound states, unlike the recently introduced supersymmetric perturbation technique which, together with other approaches based on logarithmic perturbation theory, are involved within the more general framework of the present formalism.
Dynkin, E B
1960-01-01
Theory of Markov Processes provides information pertinent to the logical foundations of the theory of Markov random processes. This book discusses the properties of the trajectories of Markov processes and their infinitesimal operators.Organized into six chapters, this book begins with an overview of the necessary concepts and theorems from measure theory. This text then provides a general definition of Markov process and investigates the operations that make possible an inspection of the class of Markov processes corresponding to a given transition function. Other chapters consider the more c
Durante, Fabrizio
2015-01-01
Principles of Copula Theory explores the state of the art on copulas and provides you with the foundation to use copulas in a variety of applications. Throughout the book, historical remarks and further readings highlight active research in the field, including new results, streamlined presentations, and new proofs of old results.After covering the essentials of copula theory, the book addresses the issue of modeling dependence among components of a random vector using copulas. It then presents copulas from the point of view of measure theory, compares methods for the approximation of copulas,
Iterative q difference Galois Theory
Hardouin, Charlotte
2009-01-01
We propose in this paper a Galois theory of $q$-difference equations where q is a root of unity. This theory is the q difference analogue of the Galois theory of iterative differential equations, that is differential equations over fields of positive characteristic. This theory contains and generalizes the Galois theory of q difference equations developed by Singer and van der Put.
Nonstandard Methods in Lie Theory
Goldbring, Isaac Martin
2009-01-01
In this thesis, we apply model theory to Lie theory and geometric group theory. These applications of model theory come via nonstandard analysis. In Lie theory, we use nonstandard methods to prove two results. First, we give a positive solution to the local form of Hilbert's Fifth Problem, which asks whether every locally euclidean local…
Almost ring theory - sixth release
Gabber, Ofer; Ramero, Lorenzo
2002-01-01
We develop almost ring theory, which is a domain of mathematics somewhere halfway between ring theory and category theory (whence the difficulty of finding appropriate MSC-class numbers). We apply this theory to valuation theory and to p-adic analytic geometry. You should really have a look at the introductions (each chapter has one).
Beyond generalized Proca theories
Heisenberg, Lavinia; Tsujikawa, Shinji
2016-01-01
We consider higher-order derivative interactions beyond second-order generalized Proca theories that propagate only the three desired polarizations of a massive vector field besides the two tensor polarizations from gravity. These new interactions follow the similar construction criteria to those arising in the extension of scalar-tensor Horndeski theories to Gleyzes-Langlois-Piazza-Vernizzi (GLPV) theories. On the maximally symmetric space-time, we perform the Hessian and Hamiltonian analysis and show the presence of a second-class constraint that removes the would-be ghost associated with the temporal component of the vector field. Furthermore, we study the behavior of linear perturbations on top of the homogeneous and isotropic cosmological background in the presence of a matter perfect fluid and find the same number of propagating degrees of freedom as in generalized Proca theories. Moreover, we obtain the conditions for the avoidance of ghosts and Laplacian instabilities of tensor, vector, and scalar per...
International Nuclear Information System (INIS)
We have recently developed a new theoretical approach to the study of polymer liquids. The theory is based on the ''reference interaction site model'' (RISM theory) of Chandler and Andersen, which has been successful in describing the structure of small molecule liquids. We have recently extended our polymer RISM theory to the case of polymer blends. In the present investigation we have applied this theory to two special binary blends: (1) the athermal mixture where we isolate structural effects, and (2) the isotopic mixture in which structurally identical polymer chains interact with dissimilar attractive interactions. By studying these two special cases we are able to obtain insights into the molecular factors which control the miscibility in polymer mixtures. 18 refs., 2 figs
International Nuclear Information System (INIS)
We discuss an aspect of string theory which has been tackled from many different perspectives, but incompletely: the role of nonlocality in the theory and its relation to the geometric shape of the string. In particular, we will describe in quantitative terms how one can zoom out from an extended object such as a string in such a way that, at sufficiently large scales, it appears structureless. Since there are no free parameters in free-string theory, the notion of large scales will be unambiguously determined. In other words, we will be able to answer the question: how and at which scale can the string be seen as a particle? In doing so, we will employ the concept of spectral dimension in a new way with respect to its usual applications in quantum gravity. The operational notions of worldsheet and target spacetime dimension in string theory are also clarified and found to be in mutual agreement. (paper)
Swanson, Donald Gary
2008-01-01
Developed from the lectures of a leading expert in plasma wave research, Plasma Kinetic Theory provides the essential material for an introductory course on plasma physics as well as the basis for a more advanced course on kinetic theory. Exploring various wave phenomena in plasmas, it offers wide-ranging coverage of the field. After introducing basic kinetic equations and the Lenard–Balescu equation, the book covers the important Vlasov–Maxwell equations. The solutions of these equations in linear and quasilinear approximations comprise the majority of kinetic theory. Another main topic in kinetic theory is to assess the effects of collisions or correlations in waves. The author discusses the effects of collisions in magnetized plasma and calculates the different transport coefficients, such as pressure tensor, viscosity, and thermal diffusion, that depend on collisions. With worked examples and problem sets that enable sound comprehension, this text presents a detailed, mathematical approach to app...
Large Spin Perturbation Theory
Alday, Luis F
2016-01-01
We consider conformal field theories around points of large twist degeneracy. Examples of this are theories with weakly broken higher spin symmetry and perturbations around generalised free fields. At the degenerate point we introduce twist conformal blocks. These are eigenfunctions of certain quartic operators and encode the contribution, to a given four-point correlator, of the whole tower of intermediate operators with a given twist. As we perturb around the degenerate point, the twist degeneracy is lifted. In many situations this breaking is controlled by inverse powers of the spin. In such cases the twist conformal blocks can be decomposed into a sequence of functions which we systematically construct. Decomposing the four-point correlator in this basis turns crossing symmetry into an algebraic problem. Our method can be applied to a wide spectrum of conformal field theories in any number of dimensions and at any order in the breaking parameter. As an example, we compute the spectrum of various theories ...
DEFF Research Database (Denmark)
Pries-Heje, Jan; Baskerville, Richard
2014-01-01
Technological knowledge has been characterized as having a scope that is specific to a particular problem. However, the information systems community is exploring forms of design science research that provide a promising avenue to technological knowledge with broader scope: design theories. Because...... design science research is materially prescriptive, it requires a different perspective in developing the breadth of applications of design theories. In this paper we propose different concepts that embody forms of general technological knowledge The concept of projectability, developed originally...... as a means of distinguishing realized generalizations from unrealized generalizations, helps explain how design theories, being prescriptive, possess a different form of applicability. The concept of entrenchment describes the use of a theory in many projections. Together these concepts provide a means...
International Nuclear Information System (INIS)
We discuss the wormhole effective interactions in string theory, thought of as a sum over two-dimensional field theories on different world sheets. The effective interactions are calculated in the ''dilute wormhole approximation,'' initially by considering the Green's functions on higher-genus Riemann surfaces, and then by calculating the effect of a complete basis of wave functions on scattering amplitudes for a surface with a boundary. The sum over wormholes is equivalent to having a world sheet of trivial topology and summing over different space-time and matter-field backgrounds. To leading order these consist of the massless fluctuations, since the tachyon cancels out when a sum is done over different spin structures going through the wormhole. In this way we recover quantized general relativity as an effective theory, from a sum over field theories on higher-genus Riemann surfaces
Kirschner, Paul A.; Kirschner, Femke; Paas, Fred
2010-01-01
Kirschner, P. A., Kirschner, F. C., & Paas, F. (2009). Cognitive load theory. In E. M. Anderman & L. H. Anderman (Eds.). Psychology of classroom learning: An encyclopedia, Volume 1, a-j (pp. 205-209). Detroit, MI: Macmillan Reference.
Einstein's theory of relativity
Born, Max
2012-01-01
Semi-technical account includes a review of classical physics (origin of space and time measurements, Ptolemaic and Copernican astronomy, laws of motion, inertia, more) and of Einstein's theories of relativity.
DEFF Research Database (Denmark)
Schindler, Samuel
2013-01-01
practices are efficient in guarding against any epistemological threat posed by theory-ladenness. In this paper I show that one can generate a thesis of theory-ladenness for experimental practices from an influential New Experimentalist account. The notion I introduce for this purpose is the concept of...... light bending in 1919 by Eddington and others) to show that TDRs are used by scientists to resolve data conflicts. I argue that the rationality of the practices which employ TDRs can be saved if the independent support of the theories driving TDRs is construed in a particular way.......The thesis of theory-ladenness of observations, in its various guises, is widely considered as either ill-conceived or harmless to the rationality of science. The latter view rests partly on the work of the proponents of New Experimentalism who have argued, among other things, that experimental...
Theory of fundamental interactions
International Nuclear Information System (INIS)
In the present article the theory of fundamental interactions is derived in a systematic way from the first principles. In the developed theory there is no separation between space-time and internal gauge space. Main equations for basic fields are derived. In is shown that the theory satisfies the correspondence principle and gives rise to new notions in the considered region. In particular, the conclusion is made about the existence of particles which are characterized not only by the mass, spin, charge but also by the moment of inertia. These are rotating particles, the particles which represent the notion of the rigid body on the microscopical level and give the key for understanding strong interactions. The main concepts and dynamical laws for these particles are formulated. The basic principles of the theory may be examined experimentally not in the distant future. 29 refs
Jarvis, Frazer
2014-01-01
The technical difficulties of algebraic number theory often make this subject appear difficult to beginners. This undergraduate textbook provides a welcome solution to these problems as it provides an approachable and thorough introduction to the topic. Algebraic Number Theory takes the reader from unique factorisation in the integers through to the modern-day number field sieve. The first few chapters consider the importance of arithmetic in fields larger than the rational numbers. Whilst some results generalise well, the unique factorisation of the integers in these more general number fields often fail. Algebraic number theory aims to overcome this problem. Most examples are taken from quadratic fields, for which calculations are easy to perform. The middle section considers more general theory and results for number fields, and the book concludes with some topics which are more likely to be suitable for advanced students, namely, the analytic class number formula and the number field sieve. This is the fi...
Relativistic theories of materials
Bressan, Aldo
1978-01-01
The theory of relativity was created in 1905 to solve a problem concerning electromagnetic fields. That solution was reached by means of profound changes in fundamental concepts and ideas that considerably affected the whole of physics. Moreover, when Einstein took gravitation into account, he was forced to develop radical changes also in our space-time concepts (1916). Relativistic works on heat, thermodynamics, and elasticity appeared as early as 1911. However, general theories having a thermodynamic basis, including heat conduction and constitutive equations, did not appear in general relativity until about 1955 for fluids and appeared only after 1960 for elastic or more general finitely deformed materials. These theories dealt with materials with memory, and in this connection some relativistic versions of the principle of material indifference were considered. Even more recently, relativistic theories incorporating finite deformations for polarizable and magnetizable materials and those in which couple s...
Dreyfus, Thomas
2015-01-01
In this paper, we develop a difference Galois theory in the setting of real fields. After proving the existence and uniqueness of the real Picard-Vessiot extension, we define the real difference Galois group and prove a Galois correspondence.
Kuang, Zhen-Bang
2014-01-01
Theory of Electroelasticity analyzes the stress, strain, electric field and electric displacement in electroelastic structures such as sensors, actuators and other smart materials and structures. This book also describes new theories such as the physical variational principle and the inertial entropy theory. It differs from the traditional method by using the physical variational principle to derive the governing equations of the piezoelectric material, whereas the Maxwell stress is obtained automatically. By using the inertial entropy theory, the temperature wave equation is obtained very easily. The book is intended for scientists, researchers and engineers in the areas of mechanics, physics, smart material and control engineering as well as mechanical, aeronautical and civil engineering, etc. Zhen-Bang Kuang is a professor at Shanghai Jiao Tong University.
2008-01-01
String Theory supporters argue that the universe we live in has eleven dimensions, out of which three spacial dimensions and a temporal one, which define the void and the space-time environment we experience daily.
Swanson, E S
2009-01-01
A brief review of theoretical progress in hadron spectroscopy and nonperturbative QCD is presented. Attention is focussed on recent lattice gauge theory, the Dyson-Schwinger formalism, unquenching constituent models, and some beyond the Standard Model physics.
International Nuclear Information System (INIS)
Members of the Institute have worked on a number of problems including the following: acceleration algorithms for the Monte Carlo analysis of lattice field, and gauge and spin theories, based on changes of variables specific to lattices of dimension 2ell; construction of quaternionic generalizations of complex quantum mechanics and field theory; wave functions for paired Hall states; black hole quantum mechanics; generalized target-space duality in curved string backgrounds; gauge symnmetry algebra of the N = 2 string; two-dimensional quantum gravity and associated string theories; organizing principles from which the signal processing of neural networks in the retina and cortex can be deduced; integrable systems of KdV type; and a theory for Kondo insulators
Close, Frank
2017-01-01
Physicist Frank Close takes the reader to the frontiers of science in a vividly told investigation of revolutionary science and enterprise from the seventeenth century to the present. He looks at what has been meant by theories of everything, explores the scientific breakthroughs they have allowed, and shows the far-reaching effects they have had on crucial aspects of life and belief. Theories of everything, he argues, can be described as those which draw on all relevant branches of knowledge to explain everything known about the universe. Such accounts may reign supreme for centuries. Then, often as a result of the advances they themselves have enabled, a new discovery is made which the current theory cannot explain. A new theory is needed which inspiration, sometimes, supplies. Moving from Isaac Newton's work on gravity and motion in the seventeenth century to thermodynamics and James Clerk Maxwell's laws of electromagnetism in the nineteenth to Max Planck's and Paul Dirac's quantum physics in the twentiet...
Morava, Jack
2012-01-01
We suggest a generalization of \\pi_0 for topological groupoids, which encodes incidence relations among the strata of the associated quotient object, and argue for its utility by example, starting from the orbit categories of the theory of compact Lie groups. [The most substantial example [\\S 2.1], however, comes from Arnol'd's classification of isolated singularities.] One of the points of this note is that Thom's theory of structurally stable forms fits quite nicely with the categorical theory of databases developed recently by D. Spivak; the other is that the stratifications studied by Thom are closely related to the phase transitions studied in physics, and that the generalization of \\pi_0 proposed here may be useful in their study: in particular, in organizing our understanding of the scaling laws which naturally accompany such phenomena, in the theory of condensed matter, biology, finance ...
International Nuclear Information System (INIS)
Assuming that a lattice gauge theory describes a fundamental attribute of Nature, it should be pointed out that such a theory in the form of a gauge glass is a weaker assumption than a regular lattice model in as much as it is not constrained by the imposition of translational invariance; translational invariance is, however, recovered approximately in the long wavelength or continuum limit. (orig./WL)
Erçetin, Şefika; Tekin, Ali
2014-01-01
The present work investigates global politics and political implications of social science and management with the aid of the latest complexity and chaos theories. Until now, deterministic chaos and nonlinear analysis have not been a focal point in this area of research. This book remedies this deficiency by utilizing these methods in the analysis of the subject matter. The authors provide the reader a detailed analysis on politics and its associated applications with the help of chaos theory, in a single edited volume.
Arlinghaus Sandra L.; Kerski Joseph
2015-01-01
Is mathematical category theory a unifying tool for geography? Here we look at a few basic category theoretical ideas and interpret them in geographic example. We also offer links to indicate how category theory has been used as such in other disciplines. Finally, we announce the direction of our research program on this topic as a way to facilitate the learning, and maintenance of learning, of GIS software – and in the spirit of Quaestiones Geographicae, invite debate, comment, and contribut...
Hokky Situngkir; Deni Khanafiah
2004-01-01
We construct a model based on social balance theory proposed by Fritz Heider to analyze the interpersonal network among social agents. The model of social balance theory provides us an interesting tool to see how a social group evolves to the possible balance state. We introduce the balance index that can be used to measure social balance in macro structure level (global balance index) or in micro structure (local balance index) to see how the local balance index influences the global balance...
Krueger, Joachim I
2016-01-01
The theory of group-selected Big God religions is a master narrative of cultural evolution. The evidence is a positive manifold of correlated assumptions and variables. Although provocative, the theory is overly elastic. Its critical ingredient - belief in Big Gods - is neither necessary nor sufficient to account for in-group prosociality and discipline. Four specific issues illustrate this elasticity.
DEFF Research Database (Denmark)
Grønlund, Bo
2002-01-01
Concept of urbanity, urban theory a short overview, Johan Asplund, William Whyte, Henri Lefebvre, Richard Serenelt, Bill Hillrer and Spree Syntax Analyses. Forelæsningsnoter til kursus 3.314 i 2001 og 3.308 i 2002.......Concept of urbanity, urban theory a short overview, Johan Asplund, William Whyte, Henri Lefebvre, Richard Serenelt, Bill Hillrer and Spree Syntax Analyses. Forelæsningsnoter til kursus 3.314 i 2001 og 3.308 i 2002....
Waerden, B
1996-01-01
From the reviews: "... Federer's timely and beautiful book indeed fills the need for a comprehensive treatise on geometric measure theory, and his detailed exposition leads from the foundations of the theory to the most recent discoveries. ... The author writes with a distinctive style which is both natural and powerfully economical in treating a complicated subject. This book is a major treatise in mathematics and is essential in the working library of the modern analyst." Bulletin of the London Mathematical Society.
Energy Technology Data Exchange (ETDEWEB)
Ahlén, Olof, E-mail: olof.ahlen@aei.mpg.de [Max-Planck-Institut für Gravitationsphysik (Albert-Einstein-Institut), Am Mühlenberg 1, DE-14476 Potsdam (Germany)
2015-12-17
These proceedings from the second Caesar Lattes meeting in Rio de Janeiro 2015 are a brief introduction to how automorphic forms appear in the low energy effective action of maximally supersymmetric string theory. The explicit example of the R{sup 4}-interaction of type IIB string theory in ten dimensions is discussed. Its Fourier expansion is interpreted in terms of perturbative and non-perturbative contributions to the four graviton amplitude.
Entrepreneurship and Economic Theory
Khalil, Elias
2006-01-01
Let us define entrepreneurship as creativity and the evolution of novelty. Let us suppose, the main thesis of the chapter, that entrepreneurship is an action that does not differ from everyday action such as walking, driving, or chewing gum. If the definition and supposition are granted we can conclude that the theory of everyday action, such as walking or chewing gum, is one and the same as the theory of evolution. The conclusion is definitely strange if not extraordinary. It is based on...
Leadership styles and theories.
Giltinane, Charlotte Louise
It is useful for healthcare professionals to be able to identify the leadership styles and theories relevant to their nursing practice. Being adept in recognising these styles enables nurses to develop their skills to become better leaders, as well as improving relationships with colleagues and other leaders, who have previously been challenging to work with. This article explores different leadership styles and theories, and explains how they relate to nursing practice.
Itoyama, H
2016-01-01
This is a brief summary of an introductory lecture for students and scholars in general given by the author at Nambu Memorial Symposium which was held at Osaka City University on September 29, 2015. We review the invention of string theory by Professor Yoichiro Nambu following the discovery of the Veneziano amplitude. We also discuss Professor Nambu's proposal on string theory in the Schild gauge in 1976 which is related to the matrix model of Yang-Mills type.
Recursion theory for metamathematics
Smullyan, Raymond M
1993-01-01
This work is a sequel to the author''s Godel''s Incompleteness Theorems, though it can be read independently by anyone familiar with Godel''s incompleteness theorem for Peano arithmetic. The book deals mainly with those aspects of recursion theory that have applications to the metamathematics of incompleteness, undecidability, and related topics. It is both an introduction to the theory and a presentation of new results in the field.