Etesi, Gabor
2012-01-01
In this paper we present a proof of a mathematical version of the strong cosmic censor conjecture attributed to Geroch-Horowitz and Penrose but formulated explicitly by Wald. The proof is based on the existence of future-inextendible causal curves in causal pasts of events on the future Cauchy horizon in a non-globally hyperbolic space-time.By examining explicit non-globally hyperbolic space-times we find that in case of several physically relevant solutions these future-inextendible curves have in fact infinite length. This way we recognize a close relationship between asymptotically flat or anti-de Sitter, physically relevant extendible space-times and the so-called Malament-Hogarth space-times which play a central role in recent investigations in the theory of "gravitational computers". This motivates us to exhibit a more sharp, more geometric formulation of the strong cosmic censor conjecture, namely "all physically relevant, asymptotically flat or anti-de Sitter but non-globally hyperbolic space-times ar...
Gong, Sheng
2014-01-01
In 1919, Bieberbach posed a seemingly simple conjecture. That "simple" conjecture challenged mathematicians in complex analysis for the following 68 years! In that time, a huge number of papers discussing the conjecture and its related problems were inspired. Finally in 1984, de Branges completed the solution. In 1989, Professor Gong wrote and published a short book in Chinese, The Bieberbach Conjecture, outlining the history of the related problems and de Branges' proof. The present volume is the English translation of that Chinese edition with modifications by the author. In particular, he includes results related to several complex variables. Open problems and a large number of new mathematical results motivated by the Bieberbach conjecture are included. Completion of a standard one-year graduate complex analysis course will prepare the reader for understanding the book. It would make a nice supplementary text for a topics course at the advanced undergraduate or graduate level.
Lang's Height Conjecture and Szpiro's Conjecture
Silverman, Joseph H
2009-01-01
It is known that Szpiro's conjecture, or equivalently the ABC-conjecture, implies Lang's conjecture giving a uniform lower bound for the canonical height of nontorsion points on elliptic curves. In this note we show that a significantly weaker version of Szpiro's conjecture, which we call "prime-depleted," suffices to prove Lang's conjecture.
Data visualisations as motivational technologies
DEFF Research Database (Denmark)
Staunæs, Dorthe; Wied, Kia
2016-01-01
This paper aims to contribute with an (affirmative) critique of current tendencies to govern and educate students’ motivation through visualisations. The paper explores how educational policy with a focus on motivating improved learning for ‘all’ children is brought into the lived life of schooling...... through the invention and increased use of (small data) visualisations. Different forms of visualisation techniques such as for instance visible learning (Hattie, 2009; Nottingham, 2013) and more locally designed concepts (as True North, Rubrics e.g.) are enacted to enhance learning and performance among...
Conjectured enumeration of Vassiliev invariants
Broadhurst, D J
1997-01-01
These conjectures are motivated by successful enumerations of irreducible Euler sums. Predictions for $\\beta_{15,10}$, $\\beta_{16,12}$ and $\\beta_{19,16}$ suggest that the action of sl and osp Lie algebras, on baguette diagrams with ladder insertions, fails to detect an invariant in each case.
The Role of Technology in Gifted Students' Motivation
Housand, Brian C.; Housand, Angela M.
2012-01-01
Although technology by itself may not be motivating, a relationship seems to exist between the opportunities that technology presents and motivation for gifted students. When technology use aligns with authentic or "real-world" applications, motivation can be enhanced. This article explores the overlap between factors that have historically been…
Volume conjecture for $SU(n)$-invariants
Chen, Qingtao; Zhu, Shengmao
2015-01-01
This paper discuss an intrinsic relation among congruent relations \\cite{CLPZ}, cyclotomic expansion and Volume Conjecture for $SU(n)$ invariants. Motivated by the congruent relations for $SU(n)$ invariants obtained in our previous work \\cite{CLPZ}, we study certain limits of the $SU(n)$ invariants at various roots of unit. First, we prove a new symmetry property for the $SU(n)$ invariants by using a symmetry of colored HOMFLYPT invariants. Then we propose some conjectural formulas including the cyclotomic expansion conjecture and volume conjecture for $SU(n)$ invariants (specialization of colored HOMFLYPT invariants). We also give the proofs of these conjectural formulas for the case of figure-eight knot.
Lang's conjectures, conjecture H, and uniformity
Abramovich, D
1995-01-01
The purpose of this note is to wish a happy birthday to Professor Lucia Caporaso.* We prove that Conjecture H of Caporaso et. al. ([CHarM], sec. 6) together with Lang's conjecture implies the uniformity of rational points on varieties of general type, as predicted in [CHarM]; a few applications in arithmetic and geometry are stated. Let X be a variety of general type defined over a number field K. It was conjectured by S. Lang that the set of rational points X(K) is not Zariski dense in X. In the paper [CHarM] of L. Caporaso, J. Harris and B. Mazur it is shown that the above conjecture of Lang implies the existence of a uniform bound on the number of K-rational points of all curves of fixed genus g over K. The paper [CHarM] has immediately created a chasm among arithmetic geometers. This chasm, which often runs right in the middle of the personalities involved, divides between loyal believers of Lang's conjecture, who marvel in this powerful implication, and the disbelievers, who try (so far in vain) to use t...
Applying the ARCS Motivation Model in Technological and Vocational Education
Liao, Hung-Chang; Wang, Ya-huei
2008-01-01
This paper describes the incorporation of Keller's ARCS (Attention, Relevance, Confidence, and Satisfaction) motivation model into traditional classroom instruction-learning process. Viewing that technological and vocational students have low confidence and motivation in learning, the authors applied the ARCS motivation model not only in the…
Taking Part in Technology Education: Elements in Students' Motivation
Autio, Ossi; Hietanoro, Jenni; Ruismaki, Heikki
2011-01-01
The purpose of this study was to determine the elements motivating comprehensive school students to study technology education. In addition, we tried to discover how students' motivation towards technology education developed over the period leading up to their school experience and the effect this might have on their future involvement with…
Lanzagorta, Marco; Jitrik, Oliverio; Uhlmann, Jeffrey; Venegas-Andraca, Salvador E.
2017-05-01
In previous research we designed an interferometric quantum seismograph that uses entangled photon states to enhance sensitivity in an optomechanic device. However, a spatially-distributed array of such sensors, with each sensor measuring only nm-vibrations, may not provide sufficient sensitivity for the prediction of major earthquakes because it fails to exploit potentially critical phase information. We conjecture that relative phase information can explain the anecdotal observations that animals such as lemurs exhibit sensitivity to impending earthquakes earlier than can be done confidently with traditional seismic technology. More specifically, we propose that lemurs use their limbs as ground motion sensors and that relative phase differences are fused in the brain in a manner similar to a phased-array or synthetic-aperture radar. In this paper we will describe a lemur-inspired quantum sensor network for early warning of earthquakes. The system uses 4 interferometric quantum seismographs (e.g., analogous to a lemurs limbs) and then conducts phase and data fusion of the seismic information. Although we discuss a quantum-based technology, the principles described can also be applied to classical sensor arrays
Gender-Based Motivational Differences in Technology Education
Virtanen, Sonja; Räikkönen, Eija; Ikonen, Pasi
2015-01-01
Because of a deeply gendered history of craft education in Finland, technology education has a strong gender-related dependence. In order to motivate girls into pursuing technological studies and to enable them to see their own potential in technology, gender sensitive approaches should be developed in technology education. This study explores…
Effect Of Technology On Motivation In EFL Classrooms
Binnur GENC ILTER
2009-01-01
In language classrooms, being in unnatural conversational situations, students need motivation more than other learning milieus. Teachers try to capture the attention of students through various methods and techniques. Many researchers in EFL teaching profession have stated that good motivation has appositive effect on foreign language learning. The purpose of this study is to explore how technology could be used to increase students’ motivation in EFL classrooms. For this purpose; a ques...
Enhancing Teachers' Motivation to Apply Humanist Information Technology Innovations
Assor, Avi
2009-01-01
This article focuses on the following issue: How can we build a training and support system that would enhance the motivation and capacity of teachers for high-quality implementation of information technology innovations guided by humanist ideas? That is, a system that would not only increase teachers' motivation to apply Humanist Information…
Factors Motivating and Hindering Information and Communication Technologies Action Competence
National Research Council Canada - National Science Library
Adile Aşkım Kurt; Yavuz Akbulut; H.Ferhan Odabaşı; Beril Ceylan; Elif Buğra Kuzu; Onur Dönmez; Özden Şahin İzmirli
2013-01-01
Information and Communication Technologies Action Competence (ICTAC) can be defined as “individuals’ motivation and capacity to voluntarily employ their ICT skills for initiating or taking part in civic actions...
Institute of Scientific and Technical Information of China (English)
LI Zi-Ping; LI Ai-Min; JIANG Jin-Huan; WANG Yong-Long
2005-01-01
The extended canonical Noether identities and canonical first Noether theorem derived from an extended action in phase space for a system with a singular Lagrangian are formulated. Using these canonical Noether identities,it can be shown that the constraint multipliers connected with the first-class constraints may not be independent, so a query to a conjecture of Dirac is presented. Based on the symmetry properties of the constrained Hamiltonian system in phase space, a counterexample to a conjecture of Dirac is given to show that Dirac's conjecture fails in such a system.We present here a different way rather than Cawley's examples and other's ones in that there is no linearization of constraints in the problem. This example has a feature that neither the primary first-class constraints nor secondary first-class constraints are generators of the gauge transformation.
On the Firoozbakht's conjecture
Sabihi, Ahmad
2016-01-01
This paper proves Firoozbakht's conjecture using Rosser and Schoenfelds' inequality on the distribution of primes. This inequality is valid for all natural numbers ${n\\geq 21}$. Firoozbakht's conjecture states that if $ {p_{n}}$ and ${p_{(n+1)}}$ are consecutive prime numbers, then ${p_{(n+1)}^{1/(n+1)}< p_{n}^{1/n}}$ for every ${n\\geq 1}$. Rosser's inequality for the ${n}$th and ${(n+1)}$th roots, changes from strictly increasing to strictly decreasing for ${n\\geq 21}$. The inequality is con...
On the Firoozbakht's conjecture
Sabihi, Ahmad
2016-01-01
This paper proves Firoozbakht's conjecture using Rosser and Schoenfelds' inequality on the distribution of primes. This inequality is valid for all natural numbers ${n\\geq 21}$. Firoozbakht's conjecture states that if $ {p_{n}}$ and ${p_{(n+1)}}$ are consecutive prime numbers, then ${p_{(n+1)}^{1/(n+1)}< p_{n}^{1/n}}$ for every ${n\\geq 1}$. Rosser's inequality for the ${n}$th and ${(n+1)}$th roots, changes from strictly increasing to strictly decreasing for ${n\\geq 21}$. The inequality is con...
Unpacking Intuition: A Conjecture
2009-01-01
Can intuition be taught? The way in which faces are recognized, the structure of natural classes, and the architecture of intuition may all be instances of the same process. The conjecture that intuition is a species of recognition memory implies that human intuitive decision making can be enormously enhanced by virtual simulation.
EFFECT OF TECHNOLOGY ON MOTIVATION IN EFL CLASSROOMS
Directory of Open Access Journals (Sweden)
Binnur GENC ILTER
2009-10-01
Full Text Available In language classrooms, being in unnatural conversational situations, students need motivation more than other learning milieus. Teachers try to capture the attention of students through various methods and techniques. Many researchers in EFL teaching profession have stated that good motivation has appositive effect on foreign language learning. The purpose of this study is to explore how technology could be used to increase students’ motivation in EFL classrooms. For this purpose; a questionnaire was administered to a group of students at Akdeniz University Preparatory Classes in 2007-2008 academic year. As a result it was found out that technology was a dynamic and challenging motivating factor in EFL classrooms and there may be some suggestions focusing on the achievement of learning objectives.
Exploring motivations for the use of bitcoin technology
Khairuddin, Irni Eliana; Sas, Corina; Clinch, Sarah; Davies, Nigel
2016-01-01
This paper presents an exploratory study focusing on user experience with Bitcoin technology. We describe interviews with 9 Bitcoin users and report findings related to users’ motivations for buying and using bitcoins. Our initial findings capture three main motivations such as Bitcoin’s predicted role in a monetary revolution, users’ increased empowerment, and their perception of real value of Bitcoin currency. We conclude with reflections on the value of these findings for HCI researchers....
Energy Technology Data Exchange (ETDEWEB)
Ronnebro, Ewa
2012-06-16
PNNL’s objective in this report is to provide DOE with a technology and manufacturing readiness assessment to identify hydrogen storage technologies’ maturity levels for early market motive and non-motive applications and to provide a path forward toward commercialization. PNNL’s Technology Readiness Assessment (TRA) is based on a combination of Technology Readiness Level (TRL) and Manufacturing Readiness Level (MRL) designations that enable evaluation of hydrogen storage technologies in varying levels of development. This approach provides a logical methodology and roadmap to enable the identification of hydrogen storage technologies, their advantages/disadvantages, gaps and R&D needs on an unbiased and transparent scale that is easily communicated to interagency partners. The TRA report documents the process used to conduct the TRA, reports the TRL and MRL for each assessed technology and provides recommendations based on the findings.
Lam, T Y
1978-01-01
From the Preface: "I felt it would be useful for graduate students to see a detailed account of the sequence of mathematical developments which was inspired by the Conjecture, and which ultimately led to its full solution.... I offered a course on Serre's Conjecture to a small group of graduate students in January, 1977 [at the University of California, Berkeley] one year after its solution by Quillen and Suslin. My course was taught very much in the spirit of a mathematical 'guided tour'. Volunteering as the guide, I took upon myself the task of charting a route through all the beautiful mathematics surrounding the main problem to be treated; the 'guide' then leads his audience through the route, on to the destination, pointing out the beautiful sceneries and historical landmarks along the way."
Hales, Thomas C
2011-01-01
In 1934, Reinhardt asked for the centrally symmetric convex domain in the plane whose best lattice packing has the lowest density. He conjectured that the unique solution up to an affine transformation is the smoothed octagon (an octagon rounded at corners by arcs of hyperbolas). This article offers a detailed strategy of proof. In particular, we show that the problem is an instance of the classical problem of Bolza in the calculus of variations. A minimizing solution is known to exist. The boundary of every minimizer is a differentiable curve with Lipschitz continuous derivative. If a minimizer is piecewise analytic, then it is a smoothed polygon (a polygon rounded at corners by arcs of hyperbolas). To complete the proof of the Reinhardt conjecture, the assumption of piecewise analyticity must be removed, and the conclusion of smoothed polygon must be strengthened to smoothed octagon.
The Parisi ultrametricity conjecture
Panchenko, Dmitry
2011-01-01
In this paper we prove that the support of a random measure on the unit ball of a separable Hilbert space that satisfies the Ghirlanda-Guerra identities must be ultrametric with probability one. This implies the Parisi ultrametricity conjecture in mean-field spin glass models, such as the Sherrington-Kirkpatrick and mixed $p$-spin models, for which Gibbs' measures are known to satisfy the Ghirlanda-Guerra identities in the thermodynamic limit.
A Quantum Focussing Conjecture
Bousso, Raphael; Leichenauer, Stefan; Wall, and Aron C
2015-01-01
We propose a universal inequality that unifies the Bousso bound with the classical focussing theorem. Given a surface $\\sigma$ that need not lie on a horizon, we define a finite generalized entropy $S_\\text{gen}$ as the area of $\\sigma$ in Planck units, plus the von Neumann entropy of its exterior. Given a null congruence $N$ orthogonal to $\\sigma$, the rate of change of $S_\\text{gen}$ per unit area defines a quantum expansion. We conjecture that the quantum expansion cannot increase along $N$. This extends the notion of universal focussing to cases where quantum matter may violate the null energy condition. Integrating the conjecture yields a precise version of the Strominger-Thompson Quantum Bousso Bound. Applied to locally parallel light-rays, the conjecture implies a Quantum Null Energy Condition: a lower bound on the stress tensor in terms of the second derivative of the von Neumann entropy. We sketch a proof of this novel relation in quantum field theory.
Green's conjecture for general covers
Aprodu, Marian
2011-01-01
We establish Green's syzygy conjecture for classes of covers of curves of higher Clifford dimension. These curves have an infinite number of minimal pencils, in particular they do not verify a well-known Brill-Noether theoretic sufficient condition that implies Green's conjecture. Secondly, we study syzygies of curves with a fixed point free involution and prove that sections of Nikulin surfaces of minimal Picard number 9, verify the classical Green Conjecture but fail the Prym-Green Conjecture on syzygies of Prym-canonical curves. This provides an explicit locus in the moduli space R_g where Green's Conjecture is known to hold.
Factors Motivating and Hindering Information and Communication Technologies Action Competence
Kurt, Adile Askim; Akbulut, Yavuz; Odabasi, H. Ferhan; Ceylan, Beril; Kuzu, Elif Bugra; Donmez, Onur; Izmirli, Ozden Sahin
2013-01-01
Information and Communication Technologies Action Competence (ICTAC) can be defined as "individuals' motivation and capacity to voluntarily employ their ICT skills for initiating or taking part in civic actions". Since academic staff and teachers in ICT related fields have crucial roles in training action-competent individuals, this…
The Role of Educational Technology in Developing Achievement Motivation
McClelland, David C.
1969-01-01
Essay focusing on how achievement motivation is developed in students and adults, with some discussion of how various dimensions of educational technology may contribute to this development. Paper written pursuant to contract 0-8-071231-1747 with the U.S. Office of Education, under provisions of the Cooperative Research Program. (LS)
The Role of Educational Technology in Developing Achievement Motivation
McClelland, David C.
1969-01-01
Essay focusing on how achievement motivation is developed in students and adults, with some discussion of how various dimensions of educational technology may contribute to this development. Paper written pursuant to contract 0-8-071231-1747 with the U.S. Office of Education, under provisions of the Cooperative Research Program. (LS)
Smart Home Technologies: Insights into Generation-Specific Acceptance Motives
Gaul, Sylvia; Ziefle, Martina
In this research we examine the generation specific acceptance motives of eHealth technologies in order to assess the likelihood of success for these new technologies. 280 participants (14 - 92 years of age) volunteered to participate in a survey, in which using motives and barriers toward smart home technologies were explored. The scenario envisaged was the use of a medical stent implemented into the body, which monitors automatically the health status and which is able to remotely communicate with the doctor. Participants were asked to evaluate the pros and cons of the usage of this technology, their acceptance motives and potential utilization barriers. In order to understand the complex nature of acceptance, personal variables (age, technical expertise, health status), individual's cognitive concepts toward ageing as well as perceived usefulness were related. Outcomes show that trust, believe in the reliability of technology, privacy and security as well as intimacy facets are essential for acceptance and should be considered in order to proactively design a successful rollout of smart home technologies.
Factors Motivating and Hindering Information and Communication Technologies Action Competence
Directory of Open Access Journals (Sweden)
Adile Aşkım Kurt
2013-01-01
Full Text Available Information and Communication Technologies Action Competence (ICTAC can be defined as “individuals’ motivation and capacity to voluntarily employ their ICT skills for initiating or taking part in civic actions”. Since academic staff and teachers in ICT related fields have crucial roles in training action-competent individuals, this study aimed to determine the views of preservice teachers and instructors in Computer Education and Instructional Technology (CEIT departments about the motivating and hindering factors regarding ICTAC. Researchers used purposeful sampling technique and identified seven instructors and 16 students attending outlier CEIT departments from four different Turkish state universities. Since there is no contemporary framework on factors motivating or hindering ICTAC, the study was conducted with a qualitative approach and the data were collected through semi-structured interviews. Factors motivating and hindering ICTAC were identified through a content analysis. Findings of the study are believed to guide ICT and ICT education professionals in training students with higher levels of ICTAC and guide the course developers to focus on relevant social responsibility issues
Trahtman, A N
2012-01-01
A word w is called a synchronizing word of deterministic finite automaton (DFA) if w sends all states of the automaton to a unique state. In 1964, Jan Cerny discovered a sequence of an n-state complete DFA possessing a minimal synchronizing word of length (n-1)^2. The Cerny conjecture claims that it is also the upper bound on the length of such a word for a complete DFA. The problem has motivated great and constantly growing number of investigations and generalizations and together with the Road Coloring problem is considered as a most fascinating old problem in the theory of finite automata. The recently known upper bound for the length of the shortest synchronizing word is now equal to n(7n^2+6n-16)/48. An effort to prove the \\v{C}erny conjecture is presented.
Energy Technology Data Exchange (ETDEWEB)
Ratsch, U. (FEST, Heidelberg (Germany))
1990-08-01
Governments of various developing countries see nuclear energy as an important tool for at least three political goals: Firstly, the expected rise in future energy demand, so they argue, can only be met if nuclear electricity production in the Third World is expanded. Fossil sources are supposed to become increasingly scarce and expensive, and they are also seen to be ecologically damaging. Technologies to harness renewable energy sources are not yet mature and still too costly. Secondly, nuclear technology is seen as one of the most advanced technologies. Mastering of it might help to diminish the technological gap between the First and the Third World. Thirdly, scientific progress in developing countries is hoped to be accelerated by operating research reactors in these countries. All of these arguments ought to be taken as serious motivations. (orig./HSCH).
Generalizing Giuga's conjecture
Grau, José María
2011-01-01
In 1950 G. Giuga studied the congruence $\\sum_{j=1}^{n-1} j^{n-1} \\equiv -1$ (mod $n$) and conjectured that it was only satisfied by prime numbers. In this work we generalize Giuga's ideas considering, for each $k \\in \\mathbb{N}$, the congruence $\\sum_{j=1}^{n-1} j^{k(n-1)} \\equiv -1$ (mod $n$). It particular, it is proved that a pair $(n,k)\\in \\mathbb{N}^2$ (with composite $n$) satisfies the congruence if and only if $n$ is a Giuga Number and $ \\lambda(n)/\\gcd(\\lambda(n),n-1)$ divides $k$. In passing, we establish some new characterizations of Giuga Numbers.
Szalma, James L
2014-12-01
Motivation is a driving force in human-technology interaction. This paper represents an effort to (a) describe a theoretical model of motivation in human technology interaction, (b) provide design principles and guidelines based on this theory, and (c) describe a sequence of steps for the. evaluation of motivational factors in human-technology interaction. Motivation theory has been relatively neglected in human factors/ergonomics (HF/E). In both research and practice, the (implicit) assumption has been that the operator is already motivated or that motivation is an organizational concern and beyond the purview of HF/E. However, technology can induce task-related boredom (e.g., automation) that can be stressful and also increase system vulnerability to performance failures. A theoretical model of motivation in human-technology interaction is proposed, based on extension of the self-determination theory of motivation to HF/E. This model provides the basis for both future research and for development of practical recommendations for design. General principles and guidelines for motivational design are described as well as a sequence of steps for the design process. Human motivation is an important concern for HF/E research and practice. Procedures in the design of both simple and complex technologies can, and should, include the evaluation of motivational characteristics of the task, interface, or system. In addition, researchers should investigate these factors in specific human-technology domains. The theory, principles, and guidelines described here can be incorporated into existing techniques for task analysis and for interface and system design.
Wang, Tao
2012-01-01
A graph is diameter two edge-critical if its diameter is two and the deletion of any edge increases the diameter. Murty and Simon conjectured that the number of edges in a diameter two edge-critical graph on $n$ vertices is at most $\\lfloor \\frac{n^{2}}{4} \\rfloor$ and the extremal graph is the complete bipartite graph $K_{\\lfloor \\frac{n}{2} \\rfloor, \\lceil \\frac{n}{2} \\rceil}$. In the series papers [8-10], the Murty-Simon Conjecture stated by Haynes et al is not the original conjecture, indeed, it is only for the diameter two edge-critical graphs of even order. Haynes et al proved the conjecture for the graphs whose complements have diameter three but only with even vertices. In this paper, we prove the Murty-Simon Conjecture for the graphs whose complements have diameter three, not only with even vertices but also odd ones.
Teixidor-i-Bigas, M
1997-01-01
Let C be an algebraic curve of genus g. Let E be a vector bundle of rank n and degree d. Consider among all subbundles F' of E of rank n' those of maximal degree d'. Then s_n'(E)= n'd-nd'\\le n'(n-n')g. If E is stable s_n'(E)>0 while if E is generic s_n'(E)\\ge n'(n-n')(g-1) . The following statement was conjectured by Lange: If 0
Institute of Scientific and Technical Information of China (English)
1994-01-01
Introduction What is the difference between instrumental and integrative motivation? What kind of motivations do students have? How can our knowledge of motivation help the language learning process? Motivation can be very important in language teaching. Students can do very well when they are motivated. Teachers, with their knowledge of motivation, can make their classes more efficient and successful. Middle school teachers, in addition to learning about the English language itself, and about teaching methods, should also learn more about motivation and how this affects our students. "When we consider language teaching, motivation can be classified as either integrative or instrumental motivation" (Luxon)
Saari's Conjecture in Celestial Mechanics
Diacu, Florin; Fujiwara, Toshiaki; Pérez-Chavela, Ernesto; Santoprete, Manuele
2008-09-01
In 1969, D. Saari conjectured that the only solutions of the Newtonian n-body problem that have constant moment of inertia are relative equilibria. For n = 3, there is a computer assisted proof of this conjecture given by R. Moeckel in 2005, [10]. The collinear case was solved the same year by F. Diacu, E. Pérez-Chavela, and M. Santoprete, [4], All the other cases are open. Denoting by U the potential energy, Saari's homographic conjecture states that if along an orbit of the n-body problem IU2 is constant, then the orbit is a homographic solution, i.e. a solution whose initial configuration remains similar to itself. In this paper, we discuss both conjectures and survey the proof of the latter for a large set of initial data. This survey follows our previous paper on this subject, [5].
A proof of Sethares' conjecture
Institute of Scientific and Technical Information of China (English)
YAO; Guowu
2004-01-01
Let ψ(z) be holomorphic in the unit disk △ and meromorphic on -△. Suppose f is a Teichmuller mapping with complex dilatation k-ψ/|ψ|. In 1968, Sethares conjectured that f is extremal if and only if either (i) ψ has a double pole or (ii) ψ has no pole of order exceeding two on △. The "if" part of the conjecture had been solved by himself. We will give the affirmative answer to the "only if" part of the conjecture. In addition, a more general criterion for extremality of quasiconformal mappings is constructed in this paper,which generalizes the "if" part of Sethares' conjecture and improves the result by Reich and Shapiro in 1990.
Hajdu, L; Tijdeman, R
2011-01-01
We say that k is a P-integer if the first phi(k) primes coprime to k form a reduced residue system modulo k. In 1980 Pomerance proved the finiteness of the set of P-integers and conjectured that 30 is the largest P-integer. We prove the conjecture assuming the Riemann Hypothesis. We further prove that there is no P-integer between 30 and 10^11 and none above 10^3500.
"Conjectural" links in complex networks
Snarskii, A. A.; Zorinets, D. I.; Lande, D. V.
2016-11-01
This paper introduces the concept of Conjectural Link for Complex Networks, in particular, social networks. Conjectural Link we understand as an implicit link, not available in the network, but supposed to be present, based on the characteristics of its topology. It is possible, for example, when in the formal description of the network some connections are skipped due to errors, deliberately hidden or withdrawn (e.g. in the case of partial destruction of the network). Introduced a parameter that allows ranking the Conjectural Link. The more this parameter - the more likely that this connection should be present in the network. This paper presents a method of recovery of partially destroyed Complex Networks using Conjectural Links finding. Presented two methods of finding the node pairs that are not linked directly to one another, but have a great possibility of Conjectural Link communication among themselves: a method based on the determination of the resistance between two nodes, and method based on the computation of the lengths of routes between two nodes. Several examples of real networks are reviewed and performed a comparison to know network links prediction methods, not intended to find the missing links in already formed networks.
Persistence Motivations of Chinese Doctoral Students in Science, Technology, Engineering, and Math
Zhou, Ji
2014-01-01
This study explored what motivated 6 Chinese international students to complete a PhD in science, technology, engineering, and math fields in the United States despite perceived dissatisfaction. This study was grounded in the value-expectancy achievement motivation theory and incorporated a Confucian cultural lens to understand motivation. Four…
Persistence Motivations of Chinese Doctoral Students in Science, Technology, Engineering, and Math
Zhou, Ji
2014-01-01
This study explored what motivated 6 Chinese international students to complete a PhD in science, technology, engineering, and math fields in the United States despite perceived dissatisfaction. This study was grounded in the value-expectancy achievement motivation theory and incorporated a Confucian cultural lens to understand motivation. Four…
Warping the Weak Gravity Conjecture
Directory of Open Access Journals (Sweden)
Karta Kooner
2016-08-01
Full Text Available The Weak Gravity Conjecture, if valid, rules out simple models of Natural Inflation by restricting their axion decay constant to be sub-Planckian. We revisit stringy attempts to realise Natural Inflation, with a single open string axionic inflaton from a probe D-brane in a warped throat. We show that warped geometries can allow the requisite super-Planckian axion decay constant to be achieved, within the supergravity approximation and consistently with the Weak Gravity Conjecture. Preliminary estimates of the brane backreaction suggest that the probe approximation may be under control. However, there is a tension between large axion decay constant and high string scale, where the requisite high string scale is difficult to achieve in all attempts to realise large field inflation using perturbative string theory. We comment on the Generalized Weak Gravity Conjecture in the light of our results.
On the base sequence conjecture
Djokovic, Dragomir Z
2010-01-01
Let BS(m,n) denote the set of base sequences (A;B;C;D), with A and B of length m and C and D of length n. The base sequence conjecture (BSC) asserts that BS(n+1,n) exist (i.e., are non-empty) for all n. This is known to be true for n <= 36 and when n is a Golay number. We show that it is also true for n=37 and n=38. It is worth pointing out that BSC is stronger than the famous Hadamard matrix conjecture. In order to demonstrate the abundance of base sequences, we have previously attached to BS(n+1,n) a graph Gamma_n and computed the Gamma_n for n <= 27. We now extend these computations and determine the Gamma_n for n=28,...,35. We also propose a conjecture describing these graphs in general.
Extensions of the Multiplicity Conjecture
2005-01-01
The Multiplicity conjecture of Herzog, Huneke, and Srinivasan states an upper bound for the multiplicity of any graded $k$-algebra as well as a lower bound for Cohen-Macaulay algebras. In this note we extend this conjecture in several directions. We discuss when these bounds are sharp, find a sharp lower bound in case of not necessarily arithmetically Cohen-Macaulay one-dimensional schemes of 3-space, and we propose an upper bound for finitely generated graded torsion modules. We establish th...
Solutions of the motivic ADHM recursion formula
Mozgovoy, Sergey
2011-01-01
We give an explicit solution of the ADHM recursion formula conjectured by Chuang, Diaconescu, and Pan. This solution is closely related to the formula for the Hodge polynomials of Higgs moduli spaces conjectured by Hausel and Rodriguez-Villegas. We solve also the twisted motivic ADHM recursion formula. As a byproduct we obtain a conjectural formula for the motives of twisted Higgs moduli spaces, which generalizes the conjecture of Hausel and Rodriguez-Villegas.
Prime numbers, quantum field theory and the Goldbach conjecture
Sanchis-Lozano, Miguel-Angel; Navarro-Salas, Jose
2012-01-01
Motivated by the Goldbach and Polignac conjectures in Number Theory, we propose the factorization of a classical non-interacting real scalar field (on a two-cylindrical spacetime) as a product of either two or three (so-called primer) fields whose Fourier expansion exclusively contains prime modes. We undertake the canonical quantization of such primer fields and construct the corresponding Fock space by introducing creation operators $a_p^{\\dag}$ (labeled by prime numbers $p$) acting on the vacuum. The analysis of our model, based on the standard rules of quantum field theory, suggests intriguing connections between different topics in Number Theory, notably the Riemann hypothesis and the Goldbach and Polignac conjectures. Our analysis also suggests that the (non) renormalizability properties of the proposed model could be linked to the possible validity or breakdown of the Goldbach conjecture for large integer numbers.
Chambers, David W
2007-01-01
Motivation is short-term focused energy. The oldest theories of motivation explain motivated activity as effort to overcome primary deficiencies, such as hunger or boredom. Such theories are difficult to apply because individuals learn idiosyncratic secondary motives as alternative ways of responding to these needs. Three prominent needs theories are discussed: Herzberg's theory of hygiene and motivational factors; McClelland's needs for achievement, power, and affiliation; and Maslow's hierarchy and theory of self-actualization. A second approach to motivation holds that individuals may be thought of as engaging in rational processes to maximize their self-interests. The presented examples of this approach include Vroom's expectancy theory, Adam's theory of inequality, and the Porter-Lawler model that addresses the question of whether satisfaction leads to high performance or vice versa. Finally, several theories of motivation as life orientation are developed.
Sharpening the weak gravity conjecture with dimensional reduction
Heidenreich, Ben; Reece, Matthew; Rudelius, Tom
2016-02-01
We investigate the behavior of the Weak Gravity Conjecture (WGC) under toroidal compactification and RG flows, finding evidence that WGC bounds for single photons become weaker in the infrared. By contrast, we find that a photon satisfying the WGC will not necessarily satisfy it after toroidal compactification when black holes charged under the Kaluza-Klein photons are considered. Doing so either requires an infinite number of states of different charges to satisfy the WGC in the original theory or a restriction on allowed compactification radii. These subtleties suggest that if the Weak Gravity Conjecture is true, we must seek a stronger form of the conjecture that is robust under compactification. We propose a "Lattice Weak Gravity Conjecture" that meets this requirement: a superextremal particle should exist for every charge in the charge lattice. The perturbative heterotic string satisfies this conjecture. We also use compactification to explore the extent to which the WGC applies to axions. We argue that gravitational instanton solutions in theories of axions coupled to dilaton-like fields are analogous to extremal black holes, motivating a WGC for axions. This is further supported by a match between the instanton action and that of wrapped black branes in a higher-dimensional UV completion.
Reed's Conjecture on hole expansions
Fouquet, Jean-Luc
2012-01-01
In 1998, Reed conjectured that for any graph $G$, $\\chi(G) \\leq \\lceil \\frac{\\omega(G) + \\Delta(G)+1}{2}\\rceil$, where $\\chi(G)$, $\\omega(G)$, and $\\Delta(G)$ respectively denote the chromatic number, the clique number and the maximum degree of $G$. In this paper, we study this conjecture for some {\\em expansions} of graphs, that is graphs obtained with the well known operation {\\em composition} of graphs. We prove that Reed's Conjecture holds for expansions of bipartite graphs, for expansions of odd holes where the minimum chromatic number of the components is even, when some component of the expansion has chromatic number 1 or when a component induces a bipartite graph. Moreover, Reed's Conjecture holds if all components have the same chromatic number, if the components have chromatic number at most 4 and when the odd hole has length 5. Finally, when $G$ is an odd hole expansion, we prove $\\chi(G)\\leq\\lceil\\frac{\\omega(G)+\\Delta(G)+1}{2}\\rceil+1$.
Stahl, Herbert R
2011-01-01
We prove the BMV (Bessis, Moussa, Villani, 1975) conjecture, which states that the function t -> Tr exp(A-tB), t \\geq 0, is the Laplace transform of a positive measure on [0,\\infty) if A and B are n x n Hermitian matrices and B is positive semidefinite.
Energy Technology Data Exchange (ETDEWEB)
Borodin, Alexei [Department of Mathematics, California Institute of Technology, Mathematics 253-37, Caltech, Pasadena, CA 91125 (United States); Novikov, Alexei [Department of Mathematics, Penn State University, University Park, State College, PA 16802 (United States)
2006-07-14
We prove a conjecture of Widom (2002 Int. Math. Res. Not. 455-64 (Preprint math/0108008)) about the reality of eigenvalues of certain infinite matrices arising in asymptotic analysis of large Toeplitz determinants. As a byproduct, we obtain a new proof of Okounkov's formula for the (determinantal) correlation functions of the Schur measures on partitions.
Conjecture of Alexander and Orbach.
Rudra, Jayanta; Doiron, Curtis
2009-03-01
The dynamical properties of fractal networks have received wide range of attention. Works on this area by several pioneering authors^1-2 have led to the introduction of the spectral dimension that dictates the dynamic properties on a fractal lattice. Most of the studies involving spectral dimension have been performed on a type of fractal lattice known as percolation network. Alexander and Orbach^2 conjectured that the spectral dimension might be exactly 4/3 for percolation networks with Euclidean dimension de >= 2. Recent numerical simulations, however, could not decisively prove or disprove this conjecture, although there are other indirect evidences that it is true. We apply a stochastic approach^3 to determine the spectral dimension of percolation network for de >= 2 and check the validity of the Alexander-Orbach conjecture. Our preliminary results on 2- and 3-dimensional percolation networks indeed show that Alexander-Orbach conjecture is true, resolving a long-standing debate. References: 1. P. G. deGennes, La Recherche 7 (1976) 919. 2. S. Alexander and R. Orbach, J. Phys. Lett. (Paris) 43 (1982) L625. 3. J. Rudra and J. Kozak, Phys. Lett A 151 (1990) 429.
Multi - instantons and Maldacena's conjecture
Dorey, N.; Hollowood, T.J.; Khoze, V.V.; Mattis, M.P.; Vandoren, S.
2007-01-01
We examine certain n-point functions Gn in N = 4 supersymmetric SU(N) gauge theory at the conformal point. In the large-N limit, we are able to sum all leading-order multiinstanton contributions exactly. We find compelling evidence for Maldacena’s conjecture: (1) The large-N k-instanton collective c
Calibrating a Measure of Gender Differences in Motivation for Learning Technology
Hwang, Young Suk; Fisher, William; Vrongistinos, Konstantinos
2009-01-01
This paper reports on the theory, design, and calibration of an instrument for measuring gender difference in motivation for learning technology. The content of the instrument was developed based upon the motivational theories of Eccles and others. More specifically, the learners' self-concept of ability, perception of technology, perception of…
Weak Gravity Conjecture and Extremal Black Holes
Cottrell, William; Soler, Pablo
2016-01-01
Motivated by the desire to improve our understanding of the Weak Gravity Conjecture, we compute the one-loop correction of charged particles to the geometry and entropy of extremal black holes in 4d. Contrary to expectations, we find that loops of massive charged particles can radically alter the classical black hole geometry and that fermion loops provide evidence for the necessity of the `magnetic' WGC cutoff. The corrections are reduced when supersymmetry is present, and disappear in ${\\cal N}=4$ supergravity. We further provide some speculative arguments that in a theory with only sub-extremal particles, classical Reisner-Nordstrom black holes actually possess an infinite microcanonical entropy, though only a finite amount is visible to an external observer.
A matter of motivation: Designing engaging interactive technologies for museums
DEFF Research Database (Denmark)
Iversen, Ole Sejer; Dindler, Christian
and motivation when designing the digital museum installations. Our conceptualization of motives and motivation is based on Cultural-Historical Theory and especially the work of Vygotsky (1982) and Hedegaard (2002) as these perspectives capture the dynamics of motivation as it develops in context.......We explore the concepts of motivation and motives in relation to inform the design of digital interactive technologies for museum exhibitions. A central issue for museums is to create strong links between the subject matter knowledge and the everyday life of the children. Pursuing such an agenda...... spaces are more successful than others in spurring this engagement. We suggest that digital technology can potentially support this “double move” in which subject matter knowledge is naturally integrated into the children’s everyday life if designers take into consideration the hierarchy of motives...
Motivating Information Technology Professionals: The case of New Zealand
Shoaib Ahmed; Nazim Taskin; DAVID J. PAULEEN; Jane Parker
2017-01-01
IT professionals play a critical role in organizations. Research indicates that they may be unique in their attitudes toward motivation and job satisfaction. In New Zealand, a shortage of skilled professionals may contribute to or impact on motivation. Using a modified model of Herzberg’s two-factor theory by Smerek and Peterson (2007), this research seeks to answer the question: what motivates New Zealand IT professionals? In response, an online questionnaire was distributed to a population ...
Effect of Technology on Motivation in EFL Classrooms
Genc Ilter, Binnur
2009-01-01
In language classrooms, being in unnatural conversational situations, students need motivation more than other learning milieus. Teachers try to capture the attention of students through various methods and techniques. Many researchers in EFL teaching profession have stated that good motivation has appositive effect on foreign language learning.…
On the Strong Direct Summand Conjecture
McCullough, Jason
2009-01-01
In this thesis, our aim is the study the Vanishing of Maps of Tor Conjecture of Hochster and Huneke. We mainly focus on an equivalent characterization called the Strong Direct Summand Conjecture, due to N. Ranganathan. Our results are separated into three chapters. In Chapter 3, we prove special cases of the Strong Direct Summand Conjecture in…
Higher rank case of Dwork's conjecture
Wan, D
2000-01-01
This is the final version of ANT-0142 ("An embedding approach to Dwork's conjecture"). It reduces the higher rank case of the conjecture over a general base variety to the rank one case over the affine space. The general rank one case is completed in ANT-0235 "Rank one case of Dwork's conjecture". Both papers will appear in JAMS.
Tsirelson's problem and Kirchberg's conjecture
Fritz, Tobias
2010-01-01
Tsirelson's problem asks whether the set of nonlocal quantum correlations with a tensor product structure for the Hilbert space of states coincides with the one where only commutativity between observables located at different sites is assumed. Here it is shown that Kirchberg's QWEP conjecture on C*-algebras implies a positive answer to this question for all bipartite scenarios. The main idea is very simple and consists of relabelling measurement outcomes by complex roots of unity, so that a k-ary observable becomes a unitary of order k. This relates Tsirelson's problem to tensor products of certain group C^*-algebras to which Kirchberg's conjecture applies. For related work, see the simultaneously appearing preprint by Junge et al.
Stability, fragility, and Rota's Conjecture
Mayhew, D.; Whittle, G.; Zwam, S.H.M. van
2010-01-01
Fix a matroid N. A matroid M is N-fragile if, for each element e of M, at least one of M\\e and M/e has no N-minor. The Bounded Canopy Conjecture is that all GF(q)-representable matroids M that have an N-minor and are N-fragile have branch width bounded by a constant depending only on q and N. A matr
Stability, fragility, and Rota's Conjecture
Mayhew, D.; Whittle, G.; Zwam, S.H.M. van
2011-01-01
Fix a matroid N. A matroid M is N-fragile if, for each element e of M, at least one of M\\e and M/e has no N-minor. The Bounded Canopy Conjecture is that all GF(q)-representable matroids M that have an N-minor and are N-fragile have branch width bounded by a constant depending only on q and N. A matr
Borodin, Alexei; Novikov, Alexei
2014-01-01
In 1969 Harold Widom published his seminal paper, which gave a complete description of orthogonal and Chebyshev polynomials on a system of smooth Jordan curves. When there were Jordan arcs present the theory of orthogonal polynomials turned out to be just the same, but for Chebyshev polynomials Widom's approach proved only an upper estimate, which he conjectured to be the correct asymptotic behavior. In this note we make some clarifications which will show that the situation is more complicated.
10 conjectures in additive number theory
Cloitre, Benoit
2011-01-01
Following an idea of Rowland we give a conjectural way to generate increasing sequences of primes using algorithms involving the gcd. These algorithms seem not so useless for searching primes since it appears we found sometime primes much more greater than the number of required iterations. In an other hand we propose new formulations of famous conjectures from the additive theory of numbers (the weak twin prime conjecture, the Polignac conjecture, the Goldbach conjecture or the very general Schinzel's hypothesis H). For the moment these are experimental results obtained using pari-gp.
Weak gravity conjecture and effective field theory
Saraswat, Prashant
2017-01-01
The weak gravity conjecture (WGC) is a proposed constraint on theories with gauge fields and gravity, requiring the existence of light charged particles and/or imposing an upper bound on the field theory cutoff Λ . If taken as a consistency requirement for effective field theories (EFTs), it rules out possibilities for model building including some models of inflation. I demonstrate simple models which satisfy all forms of the WGC, but which through Higgsing of the original gauge fields produce low-energy EFTs with gauge forces that badly violate the WGC. These models illustrate specific loopholes in arguments that motivate the WGC from a bottom-up perspective; for example the arguments based on magnetic monopoles are evaded when the magnetic confinement that occurs in a Higgs phase is accounted for. This indicates that the WGC should not be taken as a veto on EFTs, even if it turns out to be a robust property of UV quantum gravity theories. However, if the latter is true, then parametric violation of the WGC at low energy comes at the cost of nonminimal field content in the UV. I propose that only a very weak constraint is applicable to EFTs, Λ ≲(log 1/g )-1 /2Mpl , where g is the gauge coupling, motivated by entropy bounds. Remarkably, EFTs produced by Higgsing a theory that satisfies the WGC can saturate but not violate this bound.
Wong, D.; Packard, B.; Girod, M.; Pugh, K.
2000-01-01
Discusses intrinsic motivation and John Dewey's perspectives on aesthetic experiences in relation to "After 3" technology programs, based on experiences with KLICK (Kids Learning in Computer Klubhouses). Highlights include control and theories of motivation and learning; and Dewey's perspectives on the opposite of control in…
Rethinking Common Assumptions about Adolescents' Motivation to Use Technology in and out of School
Jacobs, Gloria E.
2013-01-01
Research on youth use of multiliteracies and multimodal texts often imply that youth are inherently motivated by digital technologies. In this column, I consider the nature of research into motivation and multiliteracies. I suggest that the concepts of competence, autonomy, and relatedness should be integrated with a multilayered contextual…
Pre-Service Teachers' Motivation in Using Digital Technology
Yeung, Alexander S.; Tay, Eng Guan; Hui, Chenri; Lin, Jane Huiling; Low, Ee-Ling
2014-01-01
Digital technology (DT) has a significant role to play in modern education. This study examined motivational goals of student teachers in initial teacher education in Singapore and the influences of goals on their use of DT personally and in the classroom. The participants (N = 312) responded to a survey about their motivational goals (learning…
Rethinking Common Assumptions about Adolescents' Motivation to Use Technology in and out of School
Jacobs, Gloria E.
2013-01-01
Research on youth use of multiliteracies and multimodal texts often imply that youth are inherently motivated by digital technologies. In this column, I consider the nature of research into motivation and multiliteracies. I suggest that the concepts of competence, autonomy, and relatedness should be integrated with a multilayered contextual…
Liou, Pey-Yan; Kuo, Pei-Jung
2014-01-01
Background: Few studies have examined students' attitudinal perceptions of technology. There is no appropriate instrument to measure senior high school students' motivation and self-regulation toward technology learning among the current existing instruments in the field of technology education. Purpose: The present study is to validate an…
Motivating Information Technology Professionals: The case of New Zealand
Directory of Open Access Journals (Sweden)
Shoaib Ahmed
2017-06-01
Full Text Available IT professionals play a critical role in organizations. Research indicates that they may be unique in their attitudes toward motivation and job satisfaction. In New Zealand, a shortage of skilled professionals may contribute to or impact on motivation. Using a modified model of Herzberg’s two-factor theory by Smerek and Peterson (2007, this research seeks to answer the question: what motivates New Zealand IT professionals? In response, an online questionnaire was distributed to a population of New Zealand IT professionals and the data analysed using Partial Least Squares to understand the relationship between the various dimensions of job satisfaction, the impact of personal and job characteristics, and turnover intention. The findings show that the New Zealand IT professional is primarily motivated by the nature of his or her work, followed by perceptions of responsibility, and how supervisors encourage an environment for such. Satisfaction with salary is a predictor to a lesser degree. Perhaps somewhat surprisingly, professional growth opportunities, career advancement, and recognition do not have a statistically-significant positive association with motivation. We conclude that, to motivate their IT workforce, organizations should: 1 focus on the nature of the jobs that IT professionals undertake; 2 train supervisors to provide an empowering environment; 3 offer competitive salaries to retain top talent; 4 not hesitate to employ IT professionals born outside New Zealand; and 5 take account of the singularities of the New Zealand labour market in seeking to attract, recruit and retain IT professionals. Implications for policy, practice and theory are discussed.
Haim, M; Torrecillas, B
2011-01-01
We prove that a profinite algebra whose left (right) cyclic modules are torsionless is finite dimensional and QF. We give a relative version of the notion of left (right) PF ring for pseudocompact algebras and prove it is left-right symmetric and dual to the notion of quasi-co-Frobenius coalgebras. We also prove two ring theoretic conjectures of Faith, in the setting (and supplementary hypothesis) of profinite algebras: any profinite semiartinian selfinjective algebra is finite dimensional and QF, and any FGF profinite algebra is finite dimensional QF.
A Generalization of Kneser's Conjecture
Hajiabolhassan, Hossein
2009-01-01
We investigate some coloring properties of Kneser graphs. A star-free coloring is a proper coloring $c:V(G)\\to \\Bbb{N}$ such that no path with three vertices may be colored with just two consecutive numbers. The minimum positive integer $t$ for which there exists a star-free coloring $c: V(G) \\to \\{1,2,..., t\\}$ is called the star-free chromatic number of $G$ and denoted by $\\chi_s(G)$. In view of Tucker-Ky Fan's lemma, we show that for any Kneser graph ${\\rm KG}(n,k)$ we have $\\chi_s({\\rm KG}(n,k))\\geq \\max\\{2\\chi({\\rm KG}(n,k))-10, \\chi({\\rm KG}(n,k))\\}$ where $n\\geq 2k \\geq 4$. Moreover, we show that $\\chi_s({\\rm KG}(n,k))=2\\chi({\\rm KG}(n,k))-2=2n-4k+2$ provided that $n \\leq {8\\over 3}k$. This gives a partial answer to a conjecture of [12]. Also, we conjecture that for any positive integers $n\\geq 2k \\geq 4$ we have $\\chi_s({\\rm KG}(n,k))= 2\\chi({\\rm KG}(n,k))-2$.
Directory of Open Access Journals (Sweden)
Shaker Al-Mohammadi
2014-01-01
Full Text Available In today’s globalised world, technologies have been embedded in every aspect of daily activities and discourses. The field of education made no exception and hence technologies have become an integral part of all educational systems worldwide, but with different levels and layers. The presence of information technology in English language teaching has brought about notable changes for teachers and learners alike. Accordingly, this paper investigates the impact of integrating information technologies in ELT on EFL learners’ motivation and interest. Based on an authentic comparative case study, this paper explores the influence of information technology on EFL learners’ perceptions, motivation, and interest in the context of ELT in the Tunisian higher education. The findings of this study suggest that the integration of IT in ELT heavily affects EFL students’ motivation and academic performance and hence EFL instructors should take this variable into consideration.
A proof of the Goldbach conjecture
Tan, Shanguang
2011-01-01
The Goldbach conjecture was proved in this paper. The proof was by contradiction based on the fundamental theorem of arithmetic and the theory of Linear Algebra. First, by an assumption, the Goldbach conjecture was converted into a group of linear equations. Then, by investigating solutions to the group of linear equations, reductions to absurdity were derived to prove the assumption false. Hence, the Goldbach conjecture was proved that even numbers greater than 2 can be expressed as the sum of two primes.
Hodge and Tate conjectures for hypergeometric sheaves
Terasoma, T
1997-01-01
A constructible sheaf corresponding to Gel'fand Zelevinski hypergeometric functions on a torus is called hypergeometric sheaf. We consider Hodge and Tate conjectrue for hypergeomtric sheaves. Hodge conjecture is formulated in terms of variation of Hodge strucure and Tate conjecture is done for l-adic sheaves on an open set of torus. We prove Hodge and Tate conjecture up to Hodge and Tate cycle of Fermat motifes. We use cohomological Mellin transform to get the main theorem.
The Multiplicity Conjecture in low codimensions
2004-01-01
We establish the multiplicity conjecture of Herzog, Huneke, and Srinivasan about the multiplicity of graded Cohen-Macaulay algebras over a field, for codimension two algebras and for Gorenstein algebras of codimension three. In fact, we prove stronger bounds than the conjectured ones allowing us to characterize the extremal cases. This may be seen as a converse to the multiplicity formula of Huneke and Miller that inspired the conjectural bounds.
Gao's Conjecture on Zero-Sum Sequences
Indian Academy of Sciences (India)
B Sury; R Thangadurai
2002-08-01
In this paper, we shall address three closely-related conjectures due to van Emde Boas, W D Gao and Kemnitz on zero-sum problems on $\\mathbf{Z}_p \\oplus \\mathbf{Z}_p$. We prove a number of results including a proof of the conjecture of Gao for the prime = 7 (Theorem 3.1). The conjecture of Kemnitz is also proved (Propositions 4.6, 4.9, 4.10) for many classes of sequences.
Rank one case of Dwork's conjecture
Wan, D
2000-01-01
This paper proves the general rank one case of Dwork's conjecture over the affine space. It generalizes and improves the method of ANT-0141 "Dwork's conjecture on unit root zeta functions" (Ann. Math., 150(1999), 867-929). In addition, explicit information about the zeros and poles (along the Gouv\\^ea-Mazur conjecture direction) for the unit root zeta function is obtained. The paper is to appear in JAMS.
The Monodromy Conjecture for hyperplane arrangements
Budur, Nero; Teitler, Zach
2009-01-01
The Monodromy Conjecture asserts that if c is a pole of the local topological zeta function of a hypersurface, then exp(2\\pi c) is an eigenvalue of the monodromy on the cohomology of the Milnor fiber. A stronger version of the conjecture asserts that every pole is a root of the Bernstein-Sato polynomial of the hypersurface. In this note we prove the weak version of the conjecture for hyperplane arrangements. Furthermore, we reduce the strong version to the following conjecture: -n/d is always a root of the Bernstein-Sato polynomial of an indecomposable essential central hyperplane arrangement of d hyperplanes in the affine n-space.
Prime Numbers, Quantum Field Theory and the Goldbach Conjecture
Sanchis-Lozano, Miguel-Angel; Barbero G., J. Fernando; Navarro-Salas, José
2012-09-01
Motivated by the Goldbach conjecture in number theory and the Abelian bosonization mechanism on a cylindrical two-dimensional space-time, we study the reconstruction of a real scalar field as a product of two real fermion (so-called prime) fields whose Fourier expansion exclusively contains prime modes. We undertake the canonical quantization of such prime fields and construct the corresponding Fock space by introducing creation operators bp\\dag — labeled by prime numbers p — acting on the vacuum. The analysis of our model, based on the standard rules of quantum field theory and the assumption of the Riemann hypothesis, allows us to prove that the theory is not renormalizable. We also comment on the potential consequences of this result concerning the validity or breakdown of the Goldbach conjecture for large integer numbers.
Liou, Pey-Yan; Kuo, Pei-Jung
2014-05-01
Background:Few studies have examined students' attitudinal perceptions of technology. There is no appropriate instrument to measure senior high school students' motivation and self-regulation toward technology learning among the current existing instruments in the field of technology education. Purpose:The present study is to validate an instrument for assessing senior high school students' motivation and self-regulation towards technology learning. Sample:A total of 1822 Taiwanese senior high school students (1020 males and 802 females) responded to the newly developed instrument. Design and method:The Motivation and Self-regulation towards Technology Learning (MSRTL) instrument was developed based on the previous instruments measuring students' motivation and self-regulation towards science learning. Exploratory and confirmatory factor analyses were utilized to investigate the structure of the items. Cronbach's alpha was applied for measuring the internal consistency of each scale. Furthermore, multivariate analysis of variance was used to examine gender differences. Results:Seven scales, including 'Technology learning self-efficacy,' 'Technology learning value,' 'Technology active learning strategies,' 'Technology learning environment stimulation,' 'Technology learning goal-orientation,' 'Technology learning self-regulation-triggering,' and 'Technology learning self-regulation-implementing' were confirmed for the MSRTL instrument. Moreover, the results also showed that male and female students did not present the same degree of preference in all of the scales. Conclusions:The MSRTL instrument composed of seven scales corresponding to 39 items was shown to be valid based on validity and reliability analyses. While male students tended to express more positive and active performance in the motivation scales, no gender differences were found in the self-regulation scales.
Closed-universe recollapse conjecture
Energy Technology Data Exchange (ETDEWEB)
Barrow, J.D.; Galloway, G.J.; Tipler, F.J.
1986-12-15
It is widely believed that all expanding S/sup 3/ closed universes that satisfy the standard energy conditions recollapse to a second singularity. It is shown that this is false even for Friedmann universes: an ever-expanding S/sup 3/ Friedmann universe is constructed in which the matter tensor satisfies the strong, weak and dominant energy conditions and the generic condition. A general recollapse theorem for Friedmann universes is proved if the positive pressure criterion, dominant enery condition and matter regularity condition hold, then an S/sup 3/ Friedmann universe must recollapse. It is shown that all known vacuum solutions with Cauchy surface topology S/sup 3/ or S/sup 2/XS/sup 1/ recollapse, and we conjecture that this is a property of all vacuum solutions of Einstein's equations with such Cauchy surfaces.
A Proof of Onsager's Conjecture
Isett, Philip
2016-01-01
For any $\\alpha 1/3$ due to [Eyink] and [Constantin, E, Titi], solves Onsager's conjecture that the exponent $\\alpha = 1/3$ marks the threshold for conservation of energy for weak solutions in the class $L_t^\\infty C_x^\\alpha$. The previous best results were solutions in the class $C_tC_x^\\alpha$ for $\\alpha < 1/5$, due to the author, and in the class $L_t^1 C_x^\\alpha$ for $\\alpha < 1/3$ due to Buckmaster, De Lellis and Sz\\'{e}kelyhidi, both based on the method of convex integration developed for the incompressible Euler equations by De Lellis and Sz\\'ekelyhidi. The present proof combines the method of convex integration and a new "gluing approximation" technique. The convex integration part of the proof relies on the "Mikado flows" introduced by [Daneri, Sz\\'ekelyhidi] and the framework of estimates developed in the author's previous work.
Older adults' motivated choice for technological innovation: Evidence for benefit-driven selectivity
Melenhorst, Anne-Sophie; Rogers, Wendy A.; Bouwhuis, Don G.
2006-01-01
This study examined older adults' motivation to adopt technological innovation. Sixty-eight older e-mail users and nonusers discussed the use of e-mail and of traditional communication methods in 18 focus groups. The results show older adults' benefit-driven approach to new communication technology.
Motivating Factors of Florida Community and State College Information Technology Faculty
Payne, Wendy Louise
2013-01-01
In this study the core job characteristics that contribute to the internal motivational factors and job satisfaction of information technology faculty members working at a community or state college in Florida were investigated. Fifty-four information technology faculty members working at a community or state college in Florida completed the Job…
Motivating Children to Learn: The Role of Technology Education
Campbell, Coral; Jane, Beverley
2012-01-01
Design and technology education provides children with opportunities to create solutions to specific needs in innovative ways. This paper reports on research that focused on the language that the children used when they were involved in a design and technology activity. In accessing the results of the language study, the findings suggest that the…
Edixhoven, B.; Taelman, L.
2015-01-01
The André-Oort conjecture is a problem in algebraic geometry from around 1990, with arithmetic, analytic and differential geometric aspects. Klingler, Ullmo and Yafaev, as well as Pila and Tsimerman have now shown that the Generalized Riemann Hypothesis implies the Andr´e-Oort conjecture. Both proof
Green's Conjecture for the generic canonical curve
Teixidor-I-Bigas, Montserrat
1998-01-01
Green's Conjecture states the following : syzygies of the canonical model of a curve are simple up to the p^th stage if and only if the Clifford index of C is greater than p. We prove that the generic curve of genus g satisfies Green's conjecture.
Edixhoven, B.; Taelman, L.
2015-01-01
The André-Oort conjecture is a problem in algebraic geometry from around 1990, with arithmetic, analytic and differential geometric aspects. Klingler, Ullmo and Yafaev, as well as Pila and Tsimerman have now shown that the Generalized Riemann Hypothesis implies the Andr´e-Oort conjecture. Both proof
On So's conjecture for integral circulant graphs
Directory of Open Access Journals (Sweden)
J.W. Sander
2015-04-01
According to a conjecture of {\\sc So} two integral circulant graphs are isomorphic if and only if they are isospectral, i.e. they have the same eigenvalues (counted with multiplicities. We prove a weaker form of this conjecture, namely, that two integral circulant graphs with multiplicative divisor sets are isomorphic if and only if their spectral vectors coincide.
Mathematics Reading——Goldbach＇s Conjecture
Institute of Scientific and Technical Information of China (English)
无
2004-01-01
A mathematician who thinks some statement seems true but can't prove it's true may then advance it as a conjecture. The most famous actual conjecture is one made by a German mathematician who works in Russia,Christian Goldbach (1690 1764).
On topological relaxations of chromatic conjectures
Simonyi, Gábor
2010-01-01
There are several famous unsolved conjectures about the chromatic number that were relaxed and already proven to hold for the fractional chromatic number. We discuss similar relaxations for the topological lower bound(s) of the chromatic number. In particular, we prove that such a relaxed version is true for the Behzad-Vizing conjecture and also discuss the conjectures of Hedetniemi and of Hadwiger from this point of view. For the latter, a similar statement was already proven in an earlier paper of the first author with G. Tardos, our main concern here is that the so-called odd Hadwiger conjecture looks much more difficult in this respect. We prove that the statement of the odd Hadwiger conjecture holds for large enough Kneser graphs and Schrijver graphs of any fixed chromatic number.
A matter of motivation: Designing engaging interactive technologies for museums
DEFF Research Database (Denmark)
Iversen, Ole Sejer; Dindler, Christian
spaces are more successful than others in spurring this engagement. We suggest that digital technology can potentially support this “double move” in which subject matter knowledge is naturally integrated into the children’s everyday life if designers take into consideration the hierarchy of motives......We explore the concepts of motivation and motives in relation to inform the design of digital interactive technologies for museum exhibitions. A central issue for museums is to create strong links between the subject matter knowledge and the everyday life of the children. Pursuing such an agenda...... entails a commitment to understanding structures of children curiosity, interest, and engagement and the potential intersections between the everyday life of children and museum practice. Although engagement may be said to be a pervasive phenomenon, it is obvious that some technologies and exhibition...
Motivating Mathematics Learning through an Integrated Technology Enhanced Learning Environment
Samuels, Peter
2010-01-01
Many developed nations have a serious problem with a shortage in the supply of numerate graduates, fuelled by their school students' negative attitudes towards their future study of mathematics. At the same time, the smart phone and other personal sensing technological devices are becoming commonplace amongst students in schools and universities.…
Philosophical conjectures and their refutation.
Kluge, A G
2001-06-01
Sir Karl Popper is well known for explicating science in falsificationist terms, for which his degree of corroboration formalism, C(h,e,b), has become little more than a symbol. For example, de Queiroz and Poe in this issue argue that C(h,e,b) reduces to a single relative (conditional) probability, p(e,hb), the likelihood of evidence e, given both hypothesis h and background knowledge b, and in reaching that conclusion, without stating or expressing it, they render Popper a verificationist. The contradiction they impose is easily explained--de Queiroz and Poe fail to take account of the fact that Popper derived C(h,e,b) from absolute (logical) probability and severity of test, S(e,h,b), where critical evidence, p(e,b), is fundamental. Thus, de Queiroz and Poe's conjecture that p(e,hb) = C(h,e,b) is refuted. Falsificationism, not verificationism, remains a fair description of the parsimony method of inference used in phylogenetic systematics, not withstanding de Queiroz and Poe's mistaken understanding that "statistical" probability justifies that method. Although de Queiroz and Poe assert that maximum likelihood has the power "to explain data", they do not successfully demonstrate how causal explanation is achieved or what it is that is being explained. This is not surprising, bearing in mind that what is assumed about character evolution in the accompanying likelihood model M cannot then be explained by the results of a maximum likelihood analysis.
Axion monodromy and the weak gravity conjecture
Energy Technology Data Exchange (ETDEWEB)
Hebecker, Arthur; Rompineve, Fabrizio [Heidelberg Univ. (Germany). Inst. for Theoretical Physics; Westphal, Alexander [DESY Hamburg (Germany). Theory Group
2015-12-15
Axions with broken discrete shift symmetry (axion monodromy) have recently played a central role both in the discussion of inflation and the 'relaxion' approach to the hierarchy problem. We suggest a very minimalist way to constrain such models by the weak gravity conjecture for domain walls: While the electric side of the conjecture is always satisfied if the cosine-oscillations of the axion potential are sufficiently small, the magnetic side imposes a cutoff, Λ{sup 3}∝mfM{sub pl}, independent of the height of these 'wiggles'. We compare our approach with the recent related proposal by Ibanez, Montero, Uranga and Valenzuela. We also discuss the non-trivial question which version, if any, of the weak gravity conjecture for domain walls should hold. In particular, we show that string compactifications with branes of different dimensions wrapped on different cycles lead to a 'geometric weak gravity conjecture' relating volumes of cycles, norms of corresponding forms and the volume of the compact space. Imposing this 'geometric conjecture', e.g. on the basis of the more widely accepted weak gravity conjecture for particles, provides at least some support for the (electric and magnetic) conjecture for domain walls.
Shroff, Ronnie H.; Vogel, Douglas R.
2009-01-01
Research has established that intrinsic motivation has a positive effect on learning and academic achievement. In order to investigate the phenomenon of intrinsic motivation in technology-supported learning environments, this paper investigates the factors deemed to support individual student intrinsic motivation in online discussions. A research…
The Gross conjecture over rational function fields
Institute of Scientific and Technical Information of China (English)
OUYANG; Yi
2005-01-01
We study the Gross conjecture for the cyclotomic function field extension k(∧f)/k where k = Fq(t) is the rational function field and f is a monic polynomial in Fq[t].We prove the conjecture in the Fermat curve case(i.e., when f = t(t - 1)) by a direct calculation. We also prove the case when f is irreducible, which is analogous to the Weil reciprocity law. In the general case, we manage to show the weak version of the Gross conjecture here.
Numerical Evidence for a Conjecture of Poonen
Hutz, Benjamin
2009-01-01
The purpose of this note is give some evidence in support of conjectures of Poonen, and Morton and Silverman, on the periods of rational numbers under the iteration of quadratic polynomials. In particular, Poonen conjectured that there are at most 9 periodic points defined over the rational numbers for any map in the family x^2 + c for c rational. We verify this conjecture for c values up to height 10^8. For quadratic number fields, we provide evidence that the upper bound on the exact period of Q-rational periodic point is 6.
Federal investment in health information technology: how to motivate it?
Bower, Anthony G
2005-01-01
Health care market failures include inefficient standard making, problems with coordination among local providers to optimize care, and inability to measure quality accurately, inexpensively, or reliably. Study of other industries suggests policy directions for health information technology and the magnitude of gains from improving market functioning, which are very large. A perspective drawn from U.S. industrial history--in particular railroads and the interstate highway system--suggests an investment level roughly consistent with recent estimates drawn from the medical literature. The benefits of quick action probably outweigh the benefits of delaying and choosing the perfect funding mechanism.
Kwon, Hyuksoo
2016-01-01
The purpose of this study was to investigate the effect of motivation to learn technology, as perceived by South Korean middle school students, on their attitudes toward engineering. Using the instruments of Glynn et al. (2011) and Lee (2008), the study focused on eighth and ninth grade students in four middle schools located in South Korea's…
Valk, Reimira; van der Velde, E.G.; van Engen, Marloes; Godbole, R.
2014-01-01
Purpose The purpose of this paper is to gain insight into international career motives, repatriation and career success of Indian women in Science and Technology. Design/methodology/approach In total, 30 semi-structured interviews were conducted with (upper) middle-class Indian women in Science and
Legrain, Pascal; Gillet, Nicolas; Gernigon, Christophe; Lafreniere, Marc-André
2015-01-01
The purpose of this study was to test an integrative model regarding the impact of information and communication technology (ICT) on achievement in physical education. Pupils' perceptions of autonomy-support from teacher, satisfaction of basic psychological needs, and self-determined motivation were considered to mediate the impact of ICT on…
Legrain, Pascal; Gillet, Nicolas; Gernigon, Christophe; Lafreniere, Marc-André
2015-01-01
The purpose of this study was to test an integrative model regarding the impact of information and communication technology (ICT) on achievement in physical education. Pupils' perceptions of autonomy-support from teacher, satisfaction of basic psychological needs, and self-determined motivation were considered to mediate the impact of ICT on…
A Review of the N-bound and the Maximal Mass Conjectures Using NUT-Charged dS Spacetimes
Clarkson, R; Mann, R B
2004-01-01
The proposed dS/CFT correspondence remains an intriguing paradigm in the context of string theory. Recently it has motivated two interesting conjectures: the entropic N-bound and the maximal mass conjecture. The former states that there is an upper bound to the entropy in asymptotically de Sitter spacetimes, given by the entropy of pure de Sitter space. The latter states that any asymptotically de Sitter spacetime cannot have a mass larger than the pure de Sitter case without inducing a cosmological singularity. Here we review the status of these conjectures and demonstrate their limitation. We first describe a generalization of gravitational thermodynamics to asymptotically de Sitter spacetimes, and show how to compute conserved quantities and gravitational entropy using this formalism. From this we proceed to a discussion of the N-bound and maximal mass conjectures. We then illustrate that these conjectures are not satisfied for certain asymptotically de Sitter spacetimes with NUT charge. We close with a pr...
An approximate version of Sidorenko's conjecture
Conlon, David; Sudakov, Benny
2010-01-01
A beautiful conjecture of Erd\\H{o}s-Simonovits and Sidorenko states that if H is a bipartite graph, then the random graph with edge density p has in expectation asymptotically the minimum number of copies of H over all graphs of the same order and edge density. This conjecture also has an equivalent analytic form and has connections to a broad range of topics, such as matrix theory, Markov chains, graph limits, and quasirandomness. Here we prove the conjecture if H has a vertex complete to the other part, and deduce an approximate version of the conjecture for all H. Furthermore, for a large class of bipartite graphs, we prove a stronger stability result which answers a question of Chung, Graham, and Wilson on quasirandomness for these graphs.
Trivalent graphs, volume conjectures and character varieties
Nawata, Satoshi; Zodinmawia,
2014-01-01
The generalized volume conjecture and the AJ conjecture (a.k.a. the quantum volume conjecture) are extended to $U_q(sl_2)$ colored quantum invariants of trivalent graphs. The SL(2,C) character variety of the fundamental group of the complement of a trivalent graph with $E$ edges in $S^3$ is a Lagrangian subvariety of the Hitchin moduli space over the Riemann surface of genus $g=E/3+1$. The configuration of the character variety is locally determined by large color asymptotics of the quantum invariants of the trivalent graph in terms of complex Fenchel-Nielsen coordinates. Moreover, the q-holonomic difference equation of the quantum invariants provides the quantization of the character variety. In particular, we investigate both the conjectures for the theta and tetrahedron graphs.
Proof of the Witten-Yau Conjecture
Reid, James A
2012-01-01
The Witten-Yau theorem in the AdS/CFT correspondence conjectures that the conformal boundary to AdS space must possess a metric of non-negative scalar curvature for the conformal field theory defined thereon to be free of pathologies. By employing various tools from conformal geometry - such as almost Einstein structures, collapsing sphere products and tractor bundles - we rigorously prove this conjecture.
On a conjecture on linear systems
Indian Academy of Sciences (India)
SONICA ANAND
2017-06-01
In a remark to Green’s conjecture, Paranjape and Ramanan analysed the vector bundle $E$ which is the pullback by the canonical map of the universal quotient bundle $T_\\mathbb{P}^{g−1}(−1)$ on $\\mathbb{P}^{g−1}$ and stated a more general conjecture and proved it for the curveswith Clifford Index 1 (trigonal and plane quintics). In this paper, we state the conjecturefor general linear systems and obtain results for the case of hyper-elliptic curves.
SYM Correlators and the Maldacena Conjecture
Trittmann, Uwe
2002-01-01
We report on progress in evaluating quantum filed theories with supersymmetric discrete light-cone quantization (SDLCQ). We compare the method to lattice gauge theory and point out its relevance for lattice calculations. As an exciting application we present a test of the Maldacena conjecture. We test the conjecture by evaluating the correlator of the stress-energy tensor in the strong coupling field theory and comparing to the string theory prediction of its behavior as a function of the dis...
On resolution to Wu's conjecture on Cauchy function's exterior singularities
Institute of Scientific and Technical Information of China (English)
Theodore Yaotsu Wu
2011-01-01
This is a series of studies on Wu's conjecture and on its resolution to be presented herein. Both are devoted to expound all the comprehensive properties of Cauchy's function f(z) (z = x + iy) and its integral J[∫(z)] = (2πi)-1 φ f(t)(t - z)-1dt taken along the unit circle as contour C, inside which (the open domain D+)f(z) is regular but has singularities distributed in open domain Doutside C. Resolution is given to the inverse problem that the singularities of f(z) can be determined in analytical form in terms of the values f(t) of f(z) numerically prescribed on C (｜t｜ = 1), as so enunciated by Wu's conjecture. The case of a single singularity is solved using complex algebra and analysis to acquire the solution structure for a standard reference. Multiple singularities are resolved by reducing them to a single one by elimination in principle, for which purpose a general asymptotic method is developed here for resolution to the conjecture by induction, and essential singularities aretreated with employing the generalized Hilbert transforms.These new methods are applicable to relevant problems in mathematics, engineering and technology in analogy with resolving the inverse problem presented here.
A proof of the $\\ell$-adic version of the integral identity conjecture for polynomials
Thuong, Le Quy
2012-01-01
We consider the $\\ell$-adic version of the integral identity conjecture and give a complete proof in the case of polynomials. This conjecture is among of the key foundations of the theory of motivic Donaldson-Thomas invariants for non-commutative 3d Calabi-Yau varieties, which was introduced recently by Kontsevich and Soibelman. Our approach is to use some results on the Berkovich spaces, specially the comparison theorem for nearby cycles and the K$\\ddot{\\text{u}}$nneth isomorphism for cohomology with compact support.
Motivation and Technology Use During Second-Language Study Abroad in the Digital Age
Directory of Open Access Journals (Sweden)
Aroline E. Seibert Hanson
2016-12-01
Full Text Available Abstract Study abroad culture is constantly changing (Kinginger, 2013, involving new challenges such as easier access to the first language culture via technology. There has been little research done on technology use abroad and its relationship with both linguistic gains (Coleman & Chafer, 2010; Kelly, 2010 and motivation (Allen, 2013; Irie & Ryan, 2015. To explore the role of motivation in developing a successful study abroad culture in the digital age, we documented technology use in the first language and second language of 15 college students during their summer sojourn in Argentina. We quantitatively evaluated participants’ motivation (Gardner, 1985; Ushida, 2003 and proficiency (Seibert Hanson & Carlson, 2014, and qualitatively analyzed their responses to open-ended questions about goals and culture shock. We found that higher motivation levels were correlated with greater linguistic gains and less technology use in the first language (specifically internet-related. Lower motivation levels matched increased technology use in the first language, and perceptions of failure to achieve study abroad goals and integrate into the host culture. Résumé La culture de l’étude à l’étranger est en pleine évolution (Kinginger 2013, ce qui entraîne de nouveaux défis comme l’accès facile à la culture de la langue maternelle grâce à la technologie. L’usage de la technologie à l’étranger, y compris son rapport aux acquisitions linguistiques (Coleman et Chafer, 2010 ; Kelly, 2010 et à la motivation des étudiants (Allen, 2013 ; Irie et Ryan, 2015, est un sujet peu étudié jusqu’à présent. Afin d’explorer le rôle de la motivation dans le développement réussi d’une culture de l’étude à l’étranger, nous avons documenté l’usage de la technologie dans la première et la deuxième langues d’étudiants universitaires lors de leur séjour d’été en Argentine. Nous avons analysé quantitativement la motivation
The 1 , 2 , 3-Conjecture And 1 , 2-Conjecture For Sparse Graphs
Directory of Open Access Journals (Sweden)
Cranston Daniel W.
2014-11-01
Full Text Available The 1, 2, 3-Conjecture states that the edges of a graph without isolated edges can be labeled from {1, 2, 3} so that the sums of labels at adjacent vertices are distinct. The 1, 2-Conjecture states that if vertices also receive labels and the vertex label is added to the sum of its incident edge labels, then adjacent vertices can be distinguished using only {1, 2}. We show that various configurations cannot occur in minimal counterexamples to these conjectures. Discharging then confirms the conjectures for graphs with maximum average degree less than 8/3. The conjectures are already confirmed for larger families, but the structure theorems and reducibility results are of independent interest.
Directory of Open Access Journals (Sweden)
Mingxia Zhao
2014-01-01
Full Text Available Choosing proper partners is the key to the success of the alliance. Based on the analysis of the characters of the Industrial Technology Innovation Strategic Alliance, a new kind of cooperative organization occurred in China in recent years. The problem of “adverse selection” at the stage of the its establishment is discussed in this paper. The game model is built based on motivation theory and the principle-agent theory and then proved by examples. The conclusions can be got from the model. By setting the ranges of funds, preferential policy, and sharable profits and designing membership rules, the organizer of the Industrial Technology Innovation Strategic Alliance can motivate the risk neutral applicant to reveal his real capacity and the one with higher capacity to participate intothe alliance more actively and even can set capacity threshold for applicants implicitly.
Intrinsic motivation, curiosity and learning: theory and applications in educational technologies
Oudeyer, Pierre-Yves; Gottlieb, Jacqueline; Lopes, Manuel
2016-01-01
International audience; This article studies the bi-directional causal interactions between curiosity and learning, and discusses how understanding these interactions can be leveraged in educational technology applications. First, we review recent results showing how state curiosity, and more generally the experience of novelty and surprise, can enhance learning and memory retention. Then, we discuss how psychology and neuroscience have conceptualized curiosity and intrinsic motivation, study...
Eigenvalue conjecture and colored Alexander polynomials
Mironov, A
2016-01-01
We connect two important conjectures in the theory of knot polynomials. The first one is the property Al_R(q) = Al_{[1]}(q^{|R|}) for all single hook Young diagrams R, which is known to hold for all knots. The second conjecture claims that all the mixing matrices U_{i} in the relation {\\cal R}_i = U_i{\\cal R}_1U_i^{-1} between the i-th and the first generators {\\cal R}_i of the braid group are universally expressible through the eigenvalues of {\\cal R}_1. Since the above property of Alexander polynomials is very well tested, this relation provides a new support to the eigenvalue conjecture, especially for i>2, when its direct check by evaluation of the Racah matrices and their convolutions is technically difficult.
Evidence for a Lattice Weak Gravity Conjecture
Heidenreich, Ben; Rudelius, Tom
2016-01-01
The Weak Gravity Conjecture postulates the existence of superextremal charged particles, i.e. those with mass smaller than or equal to their charge in Planck units. We present further evidence for our recent observation that in known examples a much stronger statement is true: an infinite tower of superextremal particles of different charges exists. We show that effective Kaluza-Klein field theories and perturbative string vacua respect the Sublattice Weak Gravity Conjecture, namely that a finite index sublattice of the full charge lattice exists with a superextremal particle at each site. In perturbative string theory we show that this follows from modular invariance. However, we present counterexamples to the stronger possibility that a superextremal state exists at every lattice site, including an example in which the lightest charged state is subextremal. The Sublattice Weak Gravity Conjecture has many implications both for abstract theories of quantum gravity and for real-world physics. For instance, it ...
The dynamical Mordell-Lang conjecture
Bell, Jason P; Tucker, Thomas J
2016-01-01
The Dynamical Mordell-Lang Conjecture is an analogue of the classical Mordell-Lang conjecture in the context of arithmetic dynamics. It predicts the behavior of the orbit of a point x under the action of an endomorphism f of a quasiprojective complex variety X. More precisely, it claims that for any point x in X and any subvariety V of X, the set of indices n such that the n-th iterate of x under f lies in V is a finite union of arithmetic progressions. In this book the authors present all known results about the Dynamical Mordell-Lang Conjecture, focusing mainly on a p-adic approach which provides a parametrization of the orbit of a point under an endomorphism of a variety.
Note on the reduction of Alperin's Conjecture
Puig, Lluis
2011-01-01
In a recent paper, Gabriel Navarro and Pham Huu Tiep show that the so-called Alperin Weight Conjecture can be verified via the Classification of the Finite Simple Groups, provided any simple group fulfills a very precise list of conditions. Our purpose here is to show to the interested reader that the results in our book "Frobenius categories versus Brauer blocks", Progress in Math. 274(2009), and the reduction arguments in "On the reduction of Alperin's Conjecture to the quasi-simple groups", J. of Algebra 328(2011), suggest a numerical statement - implying Alperin's Conjecture block by block - which can be reduced again to check that the same holds on the quasi-simple groups and, this time, this statement on the quasi-simple groups follows from the list of conditions demanded by Navarro and Tiep.
The volume conjecture and topological strings
Dijkgraaf, R.; Fuji, H.
2009-09-01
In this paper, we discuss a relation between Jones-Witten theory of knot invariants and topological open string theory on the basis of the volume conjecture. We find a similar Hamiltonian structure for both theories, and interpret the AJ conjecture as the D-module structure for a D-brane partition function. In order to verify our claim, we compute the free energy for the annulus contributions in the topological string using the Chern-Simons matrix model, and find that it coincides with the Reidemeister torsion in the case of the figure-eight knot complement and the SnapPea census manifold m009.
The Volume Conjecture and Topological Strings
Dijkgraaf, Robbert
2009-01-01
In this paper, we discuss a relation between Jones-Witten theory of knot invariants and topological open string theory on the basis of the volume conjecture. We find a similar Hamiltonian structure for both theories, and interpret the AJ conjecture as the D-module structure for a D-brane partition function. In order to verify our claim, we compute the free energy for the annulus contributions in the topological string using the Chern-Simons matrix model, and find that it coincides with the Reidemeister torsion in the case of the figure-eight knot complement and the SnapPea census manifold m009.
Thermodynamics of gravity favours Weak Censorship Conjecture
Acquaviva, Giovanni; Hamid, Aymen I M; Maharaj, Sunil D
2015-01-01
We use the formulation of thermodynamics of gravity as proposed by Clifton, Ellis and Tavakol on the gravitational collapse of dustlike matter, that violates the strong or weak cosmic censorship conjecture depending on the initial data. We transparently demonstrate that the gravitational entropy prefers the scenario where the stronger version is violated but the weak censorship conjecture is satisfied. This is a novel result, showing the weak cosmic censorship and hence the future asymptotically simple structure of spacetime, is being validated by the nature of gravity, without imposing any extra constraint on the form of matter.
The real Fatou conjecture (AM-144)
Graczyk, Jacek
2014-01-01
In 1920, Pierre Fatou expressed the conjecture that--except for special cases--all critical points of a rational map of the Riemann sphere tend to periodic orbits under iteration. This conjecture remains the main open problem in the dynamics of iterated maps. For the logistic family x- ax(1-x), it can be interpreted to mean that for a dense set of parameters ""a,"" an attracting periodic orbit exists. The same question appears naturally in science, where the logistic family is used to construct models in physics, ecology, and economics. In this book, Jacek Graczyk and Grzegorz Swiatek provi
Celebrating Cercignani's conjecture for the Boltzmann equation
Desvillettes, Laurent; Villani, Cédric
2010-01-01
Cercignani's conjecture assumes a linear inequality between the entropy and entropy production functionals for Boltzmann's nonlinear integral operator in rarefied gas dynamics. Related to the field of logarithmic Sobolev inequalities and spectral gap inequalities, this issue has been at the core of the renewal of the mathematical theory of convergence to thermodynamical equilibrium for rarefied gases over the past decade. In this review paper, we survey the various positive and negative results which were obtained since the conjecture was proposed in the 1980s.
On a conjecture of Kaneko and Ohno
Li, Zhong-hua
2011-01-01
Let $X_0^{\\star}(k,n,s)$ denote the sum of all multiple zeta-star values of weight $k$, depth $n$ and height $s$. Kaneko and Ohno conjecture that for any positive integers $m,n,s$ with $m,n\\geqslant s$, the difference $(-1)^mX_0^{\\star}(m+n+1,n+1,s)-(-1)^nX_0^{\\star}(m+n+1,m+1,s)$ can be expressed as a polynomial of zeta values with rational coefficients. We give a proof of this conjecture in this paper.
Celebrating Cercignani's conjecture for the Boltzmann equation
Villani, Cédric
2011-01-01
Cercignani\\'s conjecture assumes a linear inequality between the entropy and entropy production functionals for Boltzmann\\'s nonlinear integral operator in rarefied gas dynamics. Related to the field of logarithmic Sobolev inequalities and spectral gap inequalities, this issue has been at the core of the renewal of the mathematical theory of convergence to thermodynamical equilibrium for rarefied gases over the past decade. In this review paper, we survey the various positive and negative results which were obtained since the conjecture was proposed in the 1980s. © American Institute of Mathematical Sciences.
Benson, Suzanne G; Dundis, Stephen P
2003-09-01
This paper applies Maslow's Hierarchy of Needs Model to the challenges of understanding and motivating employees in a rapidly changing health care industry. The perspective that Maslow's Model brings is an essential element that should be considered as the health care arena is faced with reorganization, re-engineering, mergers, acquisitions, increases in learning demands, and the escalating role of technology in training. This paper offers a new perspective related to how Maslow's Model, as used in business/organizational settings, can be directly related to current workforce concerns: the need for security and freedom from stress, social belongingness, self-esteem, self-actualization, altered work/social environments, and new opportunities for learning and self-definition. Changes in health care will continue at an accelerated pace and with these changes will come the need for more and more training. The use of technology in training has heightened access, faster distribution, innovation and increased collaboration. However, with this technology come attendant challenges including keeping up with the technology, the increased pace of training, depersonalization, and fear of the unknown. The Maslow model provides a means for understanding these challenges in terms of universal individual needs. How does one motivate employees in the face of increased demands, particularly when they are being asked to meet these demands with fewer resources? The answer is, in large part, to make the employee feel secure, needed, and appreciated. This is not at all easy, but if leaders take into consideration the needs of the individual, the new technology that provides challenges and opportunities for meeting those needs, and provides the training to meet both sets of needs, enhanced employee motivation and commitment is possible.
New experimental results concerning the Goldbach conjecture
Deshouillers, J.-M.; Riele, H.J.J. te; Saouter, Y.
1998-01-01
The Goldbach conjecture states that every even integer $ge4$ can be written as a sum of two prime numbers. It is known to be true up to $4times 10^{11$. In this paper, new experiments on a Cray C916 supercomputer and on an SGI compute server with 18 R8000 CPUs are described, which extend this bound
Geometric approach to Ending Lamination Conjecture
Soma, Teruhiko
2008-01-01
We present a new proof of the bi-Lipschitz model theorem, which occupies the main part of the Ending Lamination Conjecture proved by Minsky and Brock-Canary-Minsky. Our proof is done by using techniques of standard hyperbolic geometry as much as possible.
Proof of the Thin Sandwich Conjecture
Bartnik, R; Bartnik, Robert; Fodor, Gyula
1993-01-01
We prove that the Thin Sandwich Conjecture in general relativity is valid, provided that the data $(g_{ab},\\dot g_{ab})$ satisfy certain geometric conditions. These conditions define an open set in the class of possible data, but are not generically satisfied. The implications for the ``superspace'' picture of the Einstein evolution equations are discussed.
On the Ramanujan conjecture over number fields
Blomer, Valentin
2010-01-01
We extend to an arbitrary number field the best known bounds towards the Ramanujan conjecture for the groups GL(n), n=2, 3, 4. In particular, we present a technique allowing to overcome the analytic obstacles posed by the presence of an infinite group of units.
The center conjecture for thick spherical buildings
Ramos-Cuevas, Carlos
2009-01-01
We prove that a convex subcomplex of a spherical building of type E7 or E8 is a subbuilding or the group of building automorphisms preserving the subcomplex has a fixed point in it. Together with previous results of Muehlherr-Tits, and Leeb and the author, this completes the proof of Tits' Center Conjecture for thick spherical buildings.
Hod mice and the mouse set conjecture
Sargsyan, Grigor
2015-01-01
The author develops the theory of Hod mice below AD_{\\mathbb{R}}+ "\\Theta is regular". He uses this theory to show that HOD of the minimal model of AD_{\\mathbb{R}}+ "\\Theta is regular" satisfies GCH. Moreover, he shows that the Mouse Set Conjecture is true in the minimal model of AD_{\\mathbb{R}}+ "\\Theta is regular".
An Intrinsic Approach to Lichnerowicz Conjecture
Indian Academy of Sciences (India)
Akhil Ranjan
2000-02-01
In this paper we give a proof of Lichnerowicz conjecture for compact simply connected manifolds which is intrinsic in the sense that it avoids the nice embeddings into eigenspaces of the Laplacian. Even if one wants to use these embeddings, this paper gives a more streamlined proof. As a byproduct, we get a simple criterion for a polynomial to be a Jacobi polynomial.
Kane, D. M.
2009-06-01
A case study is described of the redesign of an assessment task - the writing of an Optoelectronic Technology profile - to achieve improved outcomes in student education and capability development, in particular, research skills. Attention is drawn to the value of a formally scheduled discussion between teacher and student around controlling the scope of the profile via an appropriately constructed "brief", and the selection and evaluation of the reference resources to be used in completing the task. Student motivation is improved through "student publishing" and encouraging students to regard their technology profile as an example of their work that can be shown to potential employers, possibly as part of a portfolio. Students have the choice as to whether they will also use the technology profile task as a vehicle to develop teamwork experience and skills.
On the Mordell-Lang conjecture in positive characteristic
Rössler, Damian
2011-01-01
We describe an algebraic proof of a generalization of a part of the Tate-Voloch conjecture. Using jet spaces, the Mordell-Lang conjecture in positive characteristic (Hrushovski's theorem, see below) follows as a corollary.
On the geometry of thin exceptional sets in Manin's conjecture
DEFF Research Database (Denmark)
Lehmann, Brian; Tanimoto, Sho
2016-01-01
Manin’s Conjecture predicts the rate of growth of rational points of a bounded height after removing those lying on an exceptional set. We study whether the exceptional set in Manin’s Conjecture is a thin set.......Manin’s Conjecture predicts the rate of growth of rational points of a bounded height after removing those lying on an exceptional set. We study whether the exceptional set in Manin’s Conjecture is a thin set....
An improved Multiplicity Conjecture for codimension three Gorenstein algebras
2006-01-01
The Multiplicity Conjecture is a deep problem relating the multiplicity (or degree) of a Cohen-Macaulay standard graded algebra with certain extremal graded Betti numbers in its minimal free resolution. In the case of level algebras of codimension three, Zanello has proposed a stronger conjecture. We prove this conjecture for the case of codimension three graded Gorenstein algebras.
Directory of Open Access Journals (Sweden)
Gruzhevsky V.A.
2014-02-01
Full Text Available Purpose: introduction in educational process of innovative technologies aimed at creating a student-centered motivation of students on the value of physical education. Material : the study involved 379 1st year students from different regions of the Crimea and the students of the Crimean Tatar nationality. Results : determined the dominant category of motives that emphasize feature innovative technologies in shaping the personality- oriented motivation of students to physical education. Identified the following groups of motives: cognitive activity, social, emotional satisfaction from motives of exercise; motives of needs of importance of physical education in the future professional activity; motives of critical attitude to the conditions and forms of organization of physical education. Found that the fundamental principles in innovative implementations become the following: the humanization; nature- compliance and nature- appropriate; tolerance; differentiation and individuality, which is closely linked with the principles of physical education. Conclusions : the proven efficiency of formation of positive student-centered motivation among college students to physical education provided records of all significant components of the previous ethnic environment.
The volume conjecture and topological strings
Energy Technology Data Exchange (ETDEWEB)
Dijkgraaf, R. [Institute for Theoretical Physics, University of Amsterdam (Netherlands); Korteweg-de Vries Institute for Mathematics, University of Amsterdam (Netherlands); Fuji, H. [Department of Physics, Nagoya University (Japan)
2009-09-15
In this paper, we discuss a relation between Jones-Witten theory of knot invariants and topological open string theory on the basis of the volume conjecture. We find a similar Hamiltonian structure for both theories, and interpret the AJ conjecture as the D-module structure for a D-brane partition function. In order to verify our claim, we compute the free energy for the annulus contributions in the topological string using the Chern-Simons matrix model, and find that it coincides with the Reidemeister torsion in the case of the figure-eight knot complement and the SnapPea census manifold m009. (Abstract Copyright [2009], Wiley Periodicals, Inc.)
Synchronous correlation matrices and Connes’ embedding conjecture
Energy Technology Data Exchange (ETDEWEB)
Dykema, Kenneth J., E-mail: kdykema@math.tamu.edu [Department of Mathematics, Texas A& M University, College Station, Texas 77843-3368 (United States); Paulsen, Vern, E-mail: vern@math.uh.edu [Department of Mathematics, University of Houston, Houston, Texas 77204 (United States)
2016-01-15
In the work of Paulsen et al. [J. Funct. Anal. (in press); preprint arXiv:1407.6918], the concept of synchronous quantum correlation matrices was introduced and these were shown to correspond to traces on certain C*-algebras. In particular, synchronous correlation matrices arose in their study of various versions of quantum chromatic numbers of graphs and other quantum versions of graph theoretic parameters. In this paper, we develop these ideas further, focusing on the relations between synchronous correlation matrices and microstates. We prove that Connes’ embedding conjecture is equivalent to the equality of two families of synchronous quantum correlation matrices. We prove that if Connes’ embedding conjecture has a positive answer, then the tracial rank and projective rank are equal for every graph. We then apply these results to more general non-local games.
The closed-universe recollapse conjecture
Barrow, John D.; Galloway, Gregory J.; Tipler, Frank J.
1986-12-01
It is widely believed that all expanding S3 closed universes that satisfy the standard energy conditions recollapse to a second singularity. The authors show that this is false even for Friedmann universes: they construct an ever-expanding S3 Friedmann universe in which the matter tensor satisfies the strong, weak and dominant energy conditions and the generic condition. The authors prove a general recollapse theorem for Friedmann universes: if the positive pressure criterion, dominant energy condition and matter regularity condition hold, then an S3 Friedmann universe must recollapse. The authors show that all known vacuum solutions with Cauchy surface topology S3 or S2×S1 recollapse, and they conjecture that this is a property of all vacuum solutions of Einstein's equations with such Cauchy surfaces. The authors consider a number of Kantowski-Sachs and Bianchi IX universes with various matter tensors, and formulate a new recollapse conjecture for matter-filled universes.
Conjectural Equilibrium in Water-filling Games
Su, Yi
2008-01-01
This paper considers a non-cooperative game in which competing users sharing a frequency-selective interference channel selfishly optimize their power allocation in order to improve their achievable rates. Previously, it was shown that a user having the knowledge of its opponents' channel state information can make foresighted decisions and substantially improve its performance compared with the case in which it deploys the conventional iterative water-filling algorithm, which does not exploit such knowledge. This paper discusses how a foresighted user can acquire this knowledge by modeling its experienced interference as a function of its own power allocation. To characterize the outcome of the multi-user interaction, the conjectural equilibrium is introduced, and the existence of this equilibrium for the investigated water-filling game is proved. Interestingly, both the Nash equilibrium and the Stackelberg equilibrium are shown to be special cases of the generalization of conjectural equilibrium. We develop...
Gauge Identities and the Dirac Conjecture
Rothe, Heinz J.; Rothe, Klaus D.
2004-01-01
The gauge symmetries of a general dynamical system can be systematically obtained following either a Hamiltonean or a Lagrangean approach. In the former case, these symmetries are generated, according to Dirac's conjecture, by the first class constraints. In the latter approach such local symmetries are reflected in the existence of so called gauge identities. The connection between the two becomes apparent, if one works with a first order Lagrangean formulation. Our analysis applies to purel...
Haglund's conjecture on 3-column Macdonald polynomials
Blasiak, Jonah
2014-01-01
We prove a positive combinatorial formula for the Schur expansion of LLT polynomials indexed by a 3-tuple of skew shapes. This verifies a conjecture of Haglund. The proof requires expressing a noncommutative Schur function as a positive sum of monomials in Lam's algebra of ribbon Schur operators. Combining this result with the expression of Haglund, Haiman, and Loehr for transformed Macdonald polynomials in terms of LLT polynomials then yields a positive combinatorial rule for transformed Mac...
JACOBIAN CONJECTURE, TWO-DIMENSIONAL CASE
Directory of Open Access Journals (Sweden)
V. V. Starkov
2016-12-01
Full Text Available The Jacobian Conjecture was first formulated by O. Keller in 1939. In the modern form it supposes injectivity of the polynomial mapping f: R^n → R^n (C^n → C^n provided that jacobian J_f ≡ const ≠ 0. In this note we consider structure of polynomial mappings f that provide J_f ≡ const ≠ 0.
Symplectic cobordisms and the strong Weinstein conjecture
GEIGES, Hansjörg; Zehmisch, Kai
2011-01-01
We study holomorphic spheres in certain symplectic cobordisms and derive information about periodic Reeb orbits in the concave end of these cobordisms from the non-compactness of the relevant moduli spaces. We use this to confirm the strong Weinstein conjecture (predicting the existence of null-homologous Reeb links) for various higher-dimensional contact manifolds, including contact type hypersurfaces in subcritical Stein manifolds and in some cotangent bundles. The quantitative character of...
Proof of Ira Gessel's lattice path conjecture
Kauers, Manuel; Koutschan, Christoph; Zeilberger, Doron
2009-01-01
We present a computer-aided, yet fully rigorous, proof of Ira Gessel's tantalizingly simply stated conjecture that the number of ways of walking 2n steps in the region x + y ≥ 0,y ≥ 0 of the square lattice with unit steps in the east, west, north, and south directions, that start and end at the origin, equals 16n(5/6)n(1/2)n(5/3)n(2)n.
Legendrian links, causality, and the Low conjecture
Chernov, Vladimir
2008-01-01
Let $(X^{m+1}, g)$ be a globally hyperbolic spacetime with Cauchy surface diffeomorphic to an open subset of $\\mathbb R^m$. The Legendrian Low conjecture formulated by Nat\\'ario and Tod says that two events $x,y\\in X$ are causally related if and only if the Legendrian link of spheres $\\mathfrak S_x, \\mathfrak S_y$ whose points are light geodesics passing through $x$ and $y$ is non-trivial in the contact manifold of all light geodesics in $X$. The Low conjecture says that for $m=2$ the events $x,y$ are causally related if and only if $\\mathfrak S_x, \\mathfrak S_y$ is non-trivial as a topological link. We prove the Low and the Legendrian Low conjectures. We also show that similar statements hold for any globally hyperbolic $(X, g)$ such that the universal cover of its Cauchy surface is diffeomorphic to an open domain of $\\mathbb R^m.$
A unitary test of the Ratios Conjecture
Goes, John; Miller, Steven J; Montague, David; Ninsuwan, Kesinee; Peckner, Ryan; Pham, Thuy
2009-01-01
The Ratios Conjecture of Conrey, Farmer and Zirnbauer predicts the answers to numerous questions in number theory, ranging from n-level densities and correlations to mollifiers to moments and vanishing at the central point. The conjecture gives a recipe to generate these answers, which are believed to be correct up to square-root cancelation. These predictions have been verified, for suitably restricted test functions, for the 1-level density of orthogonal and symplectic families of L-functions. In this paper we verify the conjecture's predictions for the unitary family of all Dirichlet $L$-functions with prime conductor; we show square-root agreement between prediction and number theory if the support of the Fourier transform of the test function is in (-1,1), and for support up to (-2,2) we show agreement up to a power savings in the family's cardinality. The interesting feature in this family (which has not surfaced in previous investigations) is determining what is and what is not a diagonal term in the R...
The weak gravity conjecture and scalar fields
Palti, Eran
2017-08-01
We propose a generalisation of the Weak Gravity Conjecture in the presence of scalar fields. The proposal is guided by properties of extremal black holes in N=2 supergravity, but can be understood more generally in terms of forbidding towers of stable gravitationally bound states. It amounts to the statement that there must exist a particle on which the gauge force acts more strongly than gravity and the scalar forces combined. We also propose that the scalar force itself should act on this particle stronger than gravity. This implies that generically the mass of this particle decreases exponentially as a function of the scalar field expectation value for super-Planckian variations, which is behaviour predicted by the Refined Swampland Conjecture. In the context of N=2 supergravity the Weak Gravity Conjecture bound can be tied to bounds on scalar field distances in field space. Guided by this, we present a general proof that for any linear combination of moduli in any Calabi-Yau compactification of string theory the proper field distance grows at best logarithmically with the moduli values for super-Planckian distances.
Evidence for a sublattice weak gravity conjecture
Heidenreich, Ben; Reece, Matthew; Rudelius, Tom
2017-08-01
The Weak Gravity Conjecture postulates the existence of superextremal charged particles, i.e. those with mass smaller than or equal to their charge in Planck units. We present further evidence for our recent observation that in known examples a much stronger statement is true: an infinite tower of superextremal particles of different charges exists. We show that effective Kaluza-Klein field theories and perturbative string vacua respect the Sublattice Weak Gravity Conjecture, namely that a finite index sublattice of the full charge lattice exists with a superextremal particle at each site. In perturbative string theory we show that this follows from modular invariance. However, we present counterexamples to the stronger possibility that a superextremal particle exists at every lattice site, including an example in which the lightest charged particle is subextremal. The Sublattice Weak Gravity Conjecture has many implications both for abstract theories of quantum gravity and for real-world physics. For instance, it implies that if a gauge group with very small coupling e exists, then the fundamental gravitational cutoff energy of the theory is no higher than ˜ e 1/3 M Pl.
Invariant measures and the soliton resolution conjecture
Chatterjee, Sourav
2012-01-01
The soliton resolution conjecture for the focusing nonlinear Schrodinger equation (NLS) is the vaguely worded claim that a global solution of the NLS, for generic initial data, will eventually resolve into a radiation component that disperses like a linear solution, plus a localized component that behaves like a soliton or multi-soliton solution. Considered to be one of the fundamental open problems in the area of nonlinear dispersive equations, this conjecture has eluded a proof or even a precise formulation till date. This paper proves a "statistical version" of this conjecture at mass-subcritical nonlinearity, in the following sense. The uniform probability distribution on the set of all functions with a given mass and energy, if such a thing existed, would be a natural invariant measure for the NLS flow and would reflect the long-term behavior for "generic initial data" with that mass and energy. Unfortunately, such a probability measure does not exist. We circumvent this problem by constructing a sequenc...
The Tate conjecture for K3 surfaces over finite fields
Charles, François
2013-10-01
Artin's conjecture states that supersingular K3 surfaces over finite fields have Picard number 22. In this paper, we prove Artin's conjecture over fields of characteristic p>3. This implies Tate's conjecture for K3 surfaces over finite fields of characteristic p>3. Our results also yield the Tate conjecture for divisors on certain holomorphic symplectic varieties over finite fields, with some restrictions on the characteristic. As a consequence, we prove the Tate conjecture for cycles of codimension 2 on cubic fourfolds over finite fields of characteristic p>3.
Gish, Jessica; Vrkljan, Brenda; Grenier, Amanda; Van Miltenburg, Benita
2016-08-04
For older drivers, in-vehicle technology offers much potential to improve safety and increase longevity of retaining both licensure and community mobility. However, little is known about how older drivers perceive Advanced Vehicle Technologies (AVTs) based on everyday driving experience. Interviews with 35 older drivers (20 men; 15 women) aged 60-85 who owned a vehicle with at least two AVTs (e.g., back-up camera, lane departure warning) were conducted to explore the meanings that older drivers assigned to AVTs and motivations for use, including whether age-related functional changes were part of their automobile purchase decision. Findings indicate that age-related changes are not a primary reason for why older adults seek out AVTs, but they still perceived and experienced AVTs to counteract age-related changes in driving performance based upon changes they felt occurring within the body. Older drivers also described AVTs as generating a sense of comfort behind-the-wheel. Comfort with this technology was equated with convenience, ease of use, and increased feelings of safety. Discussion emphasizes how assessments of the quality of driving performance and value of technology occur in relation to an aging body. Copyright © 2016 Elsevier Ltd. All rights reserved.
On a conjecture concerning helly circle graphs
Directory of Open Access Journals (Sweden)
Durán Guillermo
2003-01-01
Full Text Available We say that G is an e-circle graph if there is a bijection between its vertices and straight lines on the cartesian plane such that two vertices are adjacent in G if and only if the corresponding lines intersect inside the circle of radius one. This definition suggests a method for deciding whether a given graph G is an e-circle graph, by constructing a convenient system S of equations and inequations which represents the structure of G, in such a way that G is an e-circle graph if and only if S has a solution. In fact, e-circle graphs are exactly the circle graphs (intersection graphs of chords in a circle, and thus this method provides an analytic way for recognizing circle graphs. A graph G is a Helly circle graph if G is a circle graph and there exists a model of G by chords such that every three pairwise intersecting chords intersect at the same point. A conjecture by Durán (2000 states that G is a Helly circle graph if and only if G is a circle graph and contains no induced diamonds (a diamond is a graph formed by four vertices and five edges. Many unsuccessful efforts - mainly based on combinatorial and geometrical approaches - have been done in order to validate this conjecture. In this work, we utilize the ideas behind the definition of e-circle graphs and restate this conjecture in terms of an equivalence between two systems of equations and inequations, providing a new, analytic tool to deal with it.
A Reduction of the Graph Reconstruction Conjecture
Directory of Open Access Journals (Sweden)
Monikandan S.
2014-08-01
Full Text Available A graph is said to be reconstructible if it is determined up to isomor- phism from the collection of all its one-vertex deleted unlabeled subgraphs. Reconstruction Conjecture (RC asserts that all graphs on at least three vertices are reconstructible. In this paper, we prove that interval-regular graphs and some new classes of graphs are reconstructible and show that RC is true if and only if all non-geodetic and non-interval-regular blocks G with diam(G = 2 or diam(Ḡ = diam(G = 3 are reconstructible
Supercongruence conjectures of Rodriguez-Villegas
McCarthy, Dermot
2009-01-01
In examining the relationship between the number of points over $\\mathbb{F}_p$ on certain Calabi-Yau manifolds and hypergeometric series which correspond to a particular period of the manifold, Rodriguez-Villegas identified 22 possible supercongruences. We provide a framework of congruences covering all 22 cases. Using this framework we prove one of the outstanding supercongruence conjectures between a special value of a truncated ordinary hypergeometric series and the $p$-th Fourier coefficient of a modular form. In the course of this work we also establish two new binomial coefficient-harmonic sum identities.
Non-Abelian Bosonization and Haldane's Conjecture
Cabra, D C; Von Reichenbach, M C
1998-01-01
We study the long wavelength limit of a spin S Heisenberg antiferromagnetic chain. The fermionic Lagrangian obtained corresponds to a perturbed level 2S SU(2) Wess-Zumino-Witten model. This effective theory is then mapped into a compact U(1) boson interacting with Z_{2S} parafermions. The analysis of this effective theory allows us to show that when S is an integer there is a mass gap to all excitations, whereas this gap vanishes in the half-odd-integer spin case. This gives a field theory treatment of the so-called Haldane's conjecture for arbitrary values of the spin S.
Empowering Polynomial Theory Conjectures with Spreadsheets
Directory of Open Access Journals (Sweden)
Chris Petersdinh
2017-06-01
Full Text Available Polynomial functions and their properties are fundamental to algebra, calculus, and mathematical modeling. Students who do not have a strong understanding of the relationship between factoring and solving equations can have difficulty with optimization problems in calculus and solving application problems in any field. Understanding function transformations is important in trigonometry, the idea of the general antiderivative, and describing the geometry of a problem mathematically. This paper presents spreadsheet activities designed to bolster students' conceptualization of the factorization theorem for polynomials, complex zeros of polynomials, and function transformations. These activities were designed to use a constructivist approach involving student experimentation and conjectures.
The Fibered Isomorphism Conjecture for Complex Manifolds
Institute of Scientific and Technical Information of China (English)
S. K. ROUSHON
2007-01-01
In this paper we show that the Fibered Isomorphism Conjecture of Farrell and Jones,corresponding to the stable topological pseudoisotopy functor, is true for the fundamental groups of a class of complex manifolds. A consequence of this result is that the Whitehead group, reduced projective class groups and the negative K-groups of the fundamental groups of these manifolds vanish whenever the fundamental group is torsion free. We also prove the same results for a class of real manifolds including a large class of 3-manifolds which has a finite sheeted cover fibering over the circle.
Clark, Stephen Allan
The impact of technology (including computers and probes, low friction carts, video camera, VCR's and electronic balances) on the motivation of adolescent science students was investigated using a naturalistic case study of college preparatory ninth grade physics classes at a comprehensive high school in the southeastern United States. The students were positively affected by the use of computer technology as compared to other "low tech" labs. The non-computer technologies had little motivational effect on the students. The most important motivational effect was the belief among the students that they could successfully operate the equipment and gather meaningful results. At times, the students spent more cognitive energy on performing the experiment than on learning the physics. This was especially true when microcomputer-based labs were used. When the technology led to results that were clear to the students and displayed in a manner that could be easily interpreted, they were generally receptive and motivated to persist at the task. Many students reported being especially motivated when a computer was used to gather the data because they "just liked computers." Furthermore, qualitative evidence suggested that they had learned the physics concept they were working on. This is in close agreement with the conceptual change model of learning in that students are most likely to change their prior conceptions when the new idea is plausible (the technology makes it so), intelligible (real time graphing, actual light rays), and fruitful (the new idea explains what they actually see). However, many of the microcomputer-based laboratory (MBL) activities and "high tech" labs were too unstructured, leaving students bewildered, confused and unmotivated. To achieve maximum motivational effects from the technology, it was necessary to reduce the cognitive demand on the students so they could concentrate on the data gathered rather than the operation of the equipment.
On the degenerated Arnold-Givental conjecture
Lu, Guangcun
2008-01-01
Let $(M, \\omega, \\tau)$ be a real symplectic manifold with nonempty and compact real part $L={\\rm Fix}(\\tau)$. We study the following degenerated version of the Arnold-Givental conjecture: $\\sharp(L\\cap\\phi(L))\\ge{\\rm Cuplength}_{\\F}(L)$ for any Hamiltonian diffeomorphism $\\phi:M\\to M$ and $\\F=\\Z, \\Z_2$. Suppose that $(M, \\omega)$ is geometrical bounded for some $J\\in{\\cal J}(M, \\omega)$ with $\\tau^\\ast J=-J$. We prove $\\sharp(L\\cap\\phi(L))\\ge {\\rm Cuplength}_{\\F}(L)$ for $\\F=\\Z_2$, and $\\F=\\Z_2, \\Z$ if $L$ is orientable, and for every Hamiltonian diffeomorphism $\\phi$ generated by a compactly supported Hamiltonian function whose Hofer norm is less than the minimal area of all nonconstant $J$-holomorphic spheres in $M$. In particular, this implies that the above degenerated Arnold-Givental conjecture holds on the K3-surfaces and closed negative monotone real symplectic manifolds of dimension $2n$ with either $n\\le 3$ or minimal Chern number $N\\ge n-2$. As consequences we get that every Hamiltonian diffeomorph...
On the Kostant conjecture for Clifford algebra
Alekseev, Anton
2011-01-01
Let g be a complex simple Lie algebra, and h be a Cartan subalgebra. In the end of 1990s, B. Kostant defined two filtrations on h, one using the Clifford algebras and the odd analogue of the Harish-Chandra projection $hc: Cl(g) \\to Cl(h)$, and the other one using the canonical isomorphism $\\check{h} = h^*$ (here $\\check{h}$ is the Cartan subalgebra in the simple Lie algebra corresponding to the dual root system) and the adjoint action of the principal sl2-triple. Kostant conjectured that the two filtrations coincide. The two filtrations arise in very different contexts, and comparing them proved to be a difficult task. Y. Bazlov settled the conjecture for g of type A using explicit expressions for primitive invariants in the exterior algebra of g. Up to now this approach did not lead to a proof for all simple Lie algebras. Recently, A. Joseph proved that the second Kostant filtration coincides with the filtration on h induced by the generalized Harish-Chandra projection $(Ug \\otimes g)^g \\to Sh \\otimes h$ and...
Dynamical Horizon Entropy Bound Conjecture in Loop Quantum Cosmology
Institute of Scientific and Technical Information of China (English)
李丽仿; 朱建阳
2012-01-01
The covariant entropy bound conjecture is an important hint for the quantum gravity, with several versions available in the literature. For cosmology, Ashtekar and Wilson-Ewing ever show the consistence between the loop gravity theory and one version of this conjecture. Recently, He and Zhang [J. High Energy Phys. 10 （2007） 077] proposed a version for the dynamical horizon of the universe, which validates the entropy bound conjecture for the cosmology filled with perfect fluid in the classical scenario when the universe is far away from the big bang singularity. However, their conjecture breaks down near big bang region. We examine this conjecture in the context of the loop quantum cosmology. With the example of photon gas, this conjecture is protected by the quantum geometry effects as expected.
On Jannsen's conjecture for Hecke characters of imaginary quadratic fields
Bars, Francesc
2007-01-01
We present a collection of results on a conjecture of Jannsen about the $p$-adic realizations associated to Hecke characters over an imaginary quadratic field $K$ of class number 1. The conjecture is easy to check for Galois groups purely of local type. We prove the conjecture under a geometric regularity condition for the imaginary quadratic field $K$ at $p$, which is related to the property that a global Galois group is purely of local type. Without this regularity assumption at $p$, we present a review of the known situations in the critical case and in the non-critical case for the realizations associated to Hecke characters over $K$. We relate the conjecture to the non-vanishing of some concrete non-critical values of the associated $p$-adic $L$-function of the Hecke character. Finally, we prove that the conjecture follows from a general conjecture on Iwasawa theory for almost all Tate twists.
Intrinsic motivation, curiosity, and learning: Theory and applications in educational technologies.
Oudeyer, P-Y; Gottlieb, J; Lopes, M
2016-01-01
This chapter studies the bidirectional causal interactions between curiosity and learning and discusses how understanding these interactions can be leveraged in educational technology applications. First, we review recent results showing how state curiosity, and more generally the experience of novelty and surprise, can enhance learning and memory retention. Then, we discuss how psychology and neuroscience have conceptualized curiosity and intrinsic motivation, studying how the brain can be intrinsically rewarded by novelty, complexity, or other measures of information. We explain how the framework of computational reinforcement learning can be used to model such mechanisms of curiosity. Then, we discuss the learning progress (LP) hypothesis, which posits a positive feedback loop between curiosity and learning. We outline experiments with robots that show how LP-driven attention and exploration can self-organize a developmental learning curriculum scaffolding efficient acquisition of multiple skills/tasks. Finally, we discuss recent work exploiting these conceptual and computational models in educational technologies, showing in particular how intelligent tutoring systems can be designed to foster curiosity and learning. © 2016 Elsevier B.V. All rights reserved.
Sorebo, Oystein; Halvari, Hallgier; Gulli, Vebjorn Flaata; Kristiansen, Roar
2009-01-01
Based on self-determination theory, this study proposes an extended information systems continuance theory in the context of teachers' utilization of e-learning technology in connection with on-site courses. In the proposed model teachers' extrinsic motivation (i.e. perceived usefulness), confirmation of pre-acceptance expectations and intrinsic…
Kerner, Charlotte; Goodyear, Victoria A.
2017-01-01
Background: Considerable numbers of young people are not meeting physical activity guidelines. Wearable fitness devices can provide opportunities for physical activity promotion. Purpose: The aim of the study was to explore whether wearable healthy lifestyle technologies impacted on adolescents' (13- to 14-year-olds) motivation for physical…
The FZZ-Duality Conjecture - A Proof
Hikida, Yasuaki
2009-01-01
We prove that the cigar conformal field theory is dual to the Sine-Liouville model, as conjectured originally by Fateev, Zamolodchikov and Zamolodchikov. Since both models possess the same chiral algebra, our task is to show that correlations of all tachyon vertex operators agree. We accomplish this goal through an off-critical version of the geometric Langlands duality for sl(2). More explicitly, we combine the well-known self-duality of Liouville theory with an intriguing correspondence between the cigar and Liouville field theory. The latter is derived through a path integral treatment. After a very detailed discussion of genus zero amplitudes, we extend the duality to arbitrary closed surfaces.
On a Conjecture of M. J. Dunwoody
Institute of Scientific and Technical Information of China (English)
Alberto Cavicchioli; Beatrice Ruini; Fulvia Spaggiari
2001-01-01
We deal with three combinatorial representations of closed orientable 3-manifolds, i.e., Heegaard diagrams, branched coverings, and crystallizations (a special class of pseudo-graphs endowed with proper edge-colorings). Exploring the connections between those theories, we prove the validity of a conjecture,stated by Dunwoody in [14], concerning the class of closed orientable 3-manifolds represented by symmetric Heegaard diagrams. As a consequence, we classify the topological and geometric structures of many interesting classes of cyclic branched coverings of (hyperbolic) knots encoded by cyclic presentations of groups. In all cases, we show that the polynomial associated with the cyclic presentation coincides (up to a multiplicative unit) with the Alexander polynomial of the considered knot. Finally, we include a partial output of a computer program which generates symmetric Heegaard diagrams of cyclic branched coverings of 3-bridge knots up to nine crossings.
The FZZ-duality conjecture. A proof
Energy Technology Data Exchange (ETDEWEB)
Hikida, Y. [High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki (Japan); Schomerus, V. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
2008-05-15
We prove that the cigar conformal field theory is dual to the Sine-Liouville model, as conjectured originally by Fateev, Zamolodchikov and Zamolodchikov. Since both models possess the same chiral algebra, our task is to show that correlations of all tachyon vertex operators agree. We accomplish this goal through an off-critical version of the geometric Langlands duality for sl(2). More explicitly, we combine the well-known self-duality of Liouville theory with an intriguing correspondence between the cigar and Liouville field theory. The latter is derived through a path integral treatment. After a very detailed discussion of genus zero amplitudes, we extend the duality to arbitrary closed surfaces. (orig.)
The Weak Gravity Conjecture in three dimensions
Energy Technology Data Exchange (ETDEWEB)
Montero, Miguel [Departamento de Física Teórica, Facultad de Ciencias,Universidad Autónoma de Madrid,Calle Francisco Tomás y Valiente 7, 28049 Madrid (Spain); Instituto de Física Teórica IFT-UAM/CSIC, Campus de Cantoblanco,C/ Nicolás Cabrera 13-15, 28049 Madrid (Spain); Shiu, Gary; Soler, Pablo [Department of Physics, University of Wisconsin-Madison,1150 University Ave, Madison, WI 53706 (United States); Department of Physics & Institute for Advanced Study,Hong Kong University of Science and Technology,Lo Ka Chung Building, Lee Shau Kee Campus, Clear Water Bay (Hong Kong)
2016-10-28
We study weakly coupled U(1) theories in AdS{sub 3}, their associated charged BTZ solutions, and their charged spectra. We find that modular invariance of the holographic dual two-dimensional CFT and compactness of the gauge group together imply the existence of charged operators with conformal dimension significantly below the black hole threshold. We regard this as a form of the Weak Gravity Conjecture (WGC) in three dimensions. We also explore the constraints posed by modular invariance on a particular discrete ℤ{sub N} symmetry which arises in our discussion. In this case, modular invariance does not guarantee the existence of light ℤ{sub N}-charged states. We also highlight the differences between our discussion and the usual heuristic arguments for the WGC based on black hole remnants.
The Weak Gravity Conjecture in three dimensions
Montero, Miguel; Soler, Pablo
2016-01-01
We study weakly coupled $U(1)$ theories in $AdS_3$, their associated charged BTZ solutions, and their charged spectra. We find that modular invariance of the holographic dual two-dimensional CFT and compactness of the gauge group together imply the existence of charged operators with conformal dimension significantly below the black hole threshold. We regard this as a form of the Weak Gravity Conjecture (WGC) in three dimensions. We also explore the constraints posed by modular invariance on a particular discrete $\\mathbb{Z}_N$ symmetry which arises in our discussion. In this case, modular invariance does not guarantee the existence of light $\\mathbb{Z}_N$-charged states. We also highlight the differences between our discussion and the usual heuristic arguments for the WGC based on black hole remnants.
The Weak Gravity Conjecture and Effective Field Theory
Saraswat, Prashant
2016-01-01
The Weak Gravity Conjecture (WGC) is a proposed constraint on theories with gauge fields and gravity, requiring the existence of light charged particles and/or imposing an upper bound on the field theory cutoff $\\Lambda$. If taken as a consistency requirement for effective field theories (EFTs), it rules out possibilities for model-building including some models of inflation. I demonstrate simple models which satisfy all forms of the WGC, but which through Higgsing of the original gauge fields produce low-energy EFTs with gauge forces that badly violate the WGC. These models illustrate specific loopholes in arguments that motivate the WGC from a bottom-up perspective; for example the arguments based on magnetic monopoles are evaded when the magnetic confinement that occurs in a Higgs phase is accounted for. This indicates that the WGC should not be taken as a veto on EFTs, even if it turns out to be a robust property of UV quantum gravity theories. However, if the latter is true then parametric violation of t...
Solution of the propeller conjecture in $\\R^3$
Heilman, Steven; Naor, Assaf
2011-01-01
It is shown that every measurable partition ${A_1,..., A_k}$ of $\\R^3$ satisfies \\sum_{i=1}^k|\\int_{A_i} xe^{-\\frac12|x|_2^2}dx|_2^2\\le 9\\pi^2. Let ${P_1,P_2,P_3}$ be the partition of $\\R^2$ into $120^\\circ$ sectors centered at the origin. The bound is sharp, with equality holding if $A_i=P_i\\times \\R$ for $i\\in {1,2,3}$ and $A_i=\\emptyset$ for $i\\in \\{4,...,k}$ (up to measure zero corrections, orthogonal transformations and renumbering of the sets $\\{A_1,...,A_k\\}$). This settles positively the 3-dimensional Propeller Conjecture of Khot and Naor (FOCS 2008). The proof of reduces the problem to a finite set of numerical inequalities which are then verified with full rigor in a computer-assisted fashion. The main consequence (and motivation) of \\eqref{eq:abs} is complexity-theoretic: the Unique Games hardness threshold of the Kernel Clustering problem with 4 \\times 4 centered and spherical hypothesis matrix equals $\\frac{2\\pi}{3}$.
A conjecture on the norm of Lyapunov mapping
Institute of Scientific and Technical Information of China (English)
Daizhan CHENG; Yahong ZHU; Hongsheng QI
2009-01-01
A conjecture that the norm of Lyapunov mapping LA equals to its restriction to the symmetric set,S,i.e.,‖LA‖ = ‖LA |s‖ was proposed in [1].In this paper,a method for numerical testing is provided first.Then,some recent progress on this conjecture is presented.
Note on a Conjecture of Gopakumar-Vafa
Institute of Scientific and Technical Information of China (English)
Jun LI; Baosen WU
2006-01-01
We rephrase the Gopakumar-Vafa conjecture on genus zero Gromov-Witten invariants of Calabi-Yau threefolds in terms of the virtual degree of the moduli of pure dimension one stable sheaves and investigate the conjecture for K3 fibred local Calabi-Yau threefolds.
On a conjecture about enumerating $(2+2)$-free posets
Yan, Sherry H F
2010-01-01
Recently, Kitaev and Remmel posed a conjecture concerning the generating function for the number of unlabeled $(2+2)$-free posets with respect to number of elements and number of minimal elements. In this paper, we present a combinatorial proof of this conjecture.
The quantum unique ergodicity conjecture for thin sets
Young, Matthew P
2013-01-01
We consider some analogs of the quantum unique ergodicity conjecture for geodesics, horocycles, or ``shrinking'' families of sets. In particular, we prove the analog of the QUE conjecture for Eisenstein series restricted to the infinite geodesic connecting 0 and infinity inside the modular surface.
Quantum hoop conjecture and a natural cutoff for vacuum energy
Yang, Rong-Jia
2015-01-01
We propose here a quantum hoop conjecture which states: the de Broglie wavelength of a quantum system can not be infinitely small, otherwise it will collapse into a quantum black hole. Based on this conjecture, we find an upper bound for the wave number of a particle, which offers a natural cutoff for the vacuum energy.
Indian Academy of Sciences (India)
S Subburam; R Thangadurai
2015-05-01
In this article, we prove that infinite number of integers satsify Erdős–Woods conjecture. Moreover, it follows that the number of natural numbers ≤ satisfies Erdős–Woods conjecture with = 2 is at least /(log ) for some positive constant > 2.
Huber, Annette
2017-01-01
This book casts the theory of periods of algebraic varieties in the natural setting of Madhav Nori’s abelian category of mixed motives. It develops Nori’s approach to mixed motives from scratch, thereby filling an important gap in the literature, and then explains the connection of mixed motives to periods, including a detailed account of the theory of period numbers in the sense of Kontsevich-Zagier and their structural properties. Period numbers are central to number theory and algebraic geometry, and also play an important role in other fields such as mathematical physics. There are long-standing conjectures about their transcendence properties, best understood in the language of cohomology of algebraic varieties or, more generally, motives. Readers of this book will discover that Nori’s unconditional construction of an abelian category of motives (over fields embeddable into the complex numbers) is particularly well suited for this purpose. Notably, Kontsevich's formal period algebra represents a to...
A B\\"ocherer-Type Conjecture for Paramodular Forms
Ryan, Nathan C
2010-01-01
In the 1980s B\\"ocherer formulated a conjecture relating the central value of the quadratic twists of the spinor L-function attached to a Siegel modular form F to the coefficients of F . He proved the conjecture when F is a Saito-Kurokawa lift. Later Kohnen and Kuss gave numerical evidence for the conjecture in the case when F is a rational eigenform that is not a Saito-Kurokawa lift. In this paper we develop a conjecture relating the central value of the quadratic twists of the spinor L-function attached to a paramodular form and the coefficients of the form. We prove the conjecture in the case when the form is a Gritsenko lift and provide numerical evidence when it is not a lift.
A remark on the Generalized Hodge Conjecture
Portelli, Dario
2010-01-01
Let X be a smooth, projective variety over the field of complex numbers. On the space H of its rational cohomology of degree i we have the arithmetic filtration F^p. On the other hand, on the space of cohomology of degree i of X with complex coefficients we have the Hodge filtration G^p. It is well known that F^p is contained in the intersection of G^p with H, and that, in general, this inclusion is strict. In this paper we propose a natural substitute S^p for the Hodge filtration space G^p such that the intersection of S^p with H is the space F^p of the arithmetic filtration. In particular, S^p is a complex subspace of G^p. This result leaves untouched Grothendieck's Generalized Hodge Conjecture. But the method used here to construct algebraic supports for suitable cohomology classes seems to me of some interest. The main technical tool is the use of semi-algebraic sets, which are available by the triangulation of complex projective algebraic varieties.
Relaxion monodromy and the Weak Gravity Conjecture
Ibáñez, L. E.; Montero, M.; Uranga, A. M.; Valenzuela, I.
2016-04-01
The recently proposed relaxion models require extremely large trans-Planckian axion excursions as well as a potential explicitly violating the axion shift symmetry. The latter property is however inconsistent with the axion periodicity, which corresponds to a gauged discrete shift symmetry. A way to make things consistent is to use monodromy, i.e. both the axion and the potential parameters transform under the discrete shift symmetry. The structure is better described in terms of a 3-form field C μνρ coupling to the SM Higgs through its field strength F 4. The 4-form also couples linearly to the relaxion, in the Kaloper-Sorbo fashion. The extremely small relaxion-Higgs coupling arises in a see-saw fashion as g ≃ F 4 /f , with f being the axion decay constant. We discuss constraints on this type of constructions from membrane nucleation and the Weak Gravity Conjecture. The latter requires the existence of membranes, whose too fast nucleation could in principle drive the theory out of control, unless the cut-off scale is lowered. This allows to rule out the simplest models with the QCD axion as relaxion candidate on purely theoretical grounds. We also discuss possible avenues to embed this structure into string theory.
Tests of conjectures on multiple Watson values
Broadhurst, David
2015-01-01
I define multiple Watson values (MWVs) as iterated integrals, on the interval $x\\in[0,1]$, of the 6 differential forms $A=d\\log(x)$, $B=-d\\log(1-x)$, $T=-d\\log(1-z_1x)$, $U=-d\\log(1-z_2x)$, $V=-d\\log(1-z_3x)$ and $W=-d\\log(1-z_4x)$, where $z_1=\\gamma^2$, $z_2=\\gamma/(1+\\gamma)$, $z_3=\\gamma^2/(1-\\gamma)$ and $z_4=\\gamma=2\\sin(\\pi/14)$ solves the cubic $(1-\\gamma^2)(1-\\gamma)=\\gamma$. Following a suggestion by Pierre Deligne, I conjecture that the dimension of the space of ${\\mathbb Z}$-linearly independent MWVs of weight $w$ is the number $D_w$ generated by $1/(1-2x-x^2-x^3)=1+\\sum_{w>0}D_w x^w$. This agrees with 6639 integer relation searches, of dimensions up to $D_5+1=85$, performed at 2000-digit precision, for $w<6$.
Empirical Limits on the Russell Conjecture
Reddick, Rachel
2013-01-01
The Russell Conjecture states that there is an unproven possibility of small (<1 m) hollow heat-resistant objects (HoHOs) in Earth orbit or otherwise present in the inner solar system or asteroid belt. While such objects are not the current target of any ongoing searches, we can place stringent limits on their presence using current optical and infrared surveys. The high albedo of HoHOs partially compensates for their small size. As such, we find that no HoHOs greater than 10 cm in radius to a distance of at least 30,000 km, by the Air Force Space Surveillance System. Objects of that size in a stable orbit at 384,000 km (the Earth-Moon distance) may be detected and confirmed by more infrequent, deeper sweeps of the same system. However, it remains possible for undetected HoHOs to exist in near-Earth or Martian orbit. We discuss the prospects of finding such HoHOs in the near future with new telescopes such as LSST.
Planckian axions and the Weak Gravity Conjecture
Bachlechner, Thomas C.; Long, Cody; McAllister, Liam
2016-01-01
Several recent works [1-3] have claimed that the Weak Gravity Conjecture (WGC) excludes super-Planckian displacements of axion fields, and hence large-field axion inflation, in the absence of monodromy. We argue that in theories with N ≫ 1 axions, super-Planckian axion diameters D are readily allowed by the WGC. We clarify the non-trivial relationship between the kinetic matrix K — unambiguously defined by its form in a Minkowski-reduced basis — and the diameter of the axion fundamental domain, emphasizing that in general the diameter is not solely determined by the eigenvalues f 1 2 ≤ ṡ ṡ ṡ ≤ f N 2 of K: the orientations of the eigenvectors with respect to the identifications imposed by instantons must be incorporated. In particular, even if one were to impose the condition f N M pl does not immediately imply the existence of unsuppressed higher harmonic contributions to the potential. Finally, we argue that in effective axion-gravity theories, the zero-form version of the WGC can be satisfied by gravitational instantons that make negligible contributions to the potential.
Planckian Axions and the Weak Gravity Conjecture
Bachlechner, Thomas C; McAllister, Liam
2015-01-01
Several recent works have claimed that the Weak Gravity Conjecture (WGC) excludes super-Planckian displacements of axion fields, and hence large-field axion inflation, in the absence of monodromy. We argue that in theories with $N\\gg1$ axions, super-Planckian axion diameters $\\cal{D}$ are readily allowed by the WGC. We clarify the nontrivial relationship between the kinetic matrix $K$ --- unambiguously defined by its form in a Minkowski-reduced basis --- and the diameter of the axion fundamental domain, emphasizing that in general the diameter is not solely determined by the eigenvalues $f_1^2 \\le ... \\le f_N^2$ of $K$: the orientations of the eigenvectors with respect to the identifications imposed by instantons must be incorporated. In particular, even if one were to impose the condition $f_NM_{pl}$ does not immediately imply the existence of unsuppressed higher harmonic contributions to the potential. Finally, we argue that in effective axion-gravity theories, the zero-form version of the WGC can be satisf...
Contractor renormalization group and the Haldane conjecture
Energy Technology Data Exchange (ETDEWEB)
Weinstein, Marvin
2001-05-01
The contractor renormalization group formalism (CORE) is a real-space renormalization group method which is the Hamiltonian analogue of the Wilson exact renormalization group equations. In an earlier paper [Phys. Rev. D 61, 034505 (2000)] I showed that the CORE method could be used to map a theory of free quarks and quarks interacting with gluons into a generalized frustrated Heisenberg antiferromagnet (HAF) and proposed using CORE methods to study these theories. Since generalizations of HAF's exhibit all sorts of subtle behavior which, from a continuum point of view, are related to topological properties of the theory, it is important to know that CORE can be used to extract this physics. In this paper I show that despite the folklore which asserts that all real-space renormalization group schemes are necessarily inaccurate, simple CORE computations can give highly accurate results even if one only keeps a small number of states per block and a few terms in the cluster expansion. In addition I argue that even very simple CORE computations give a much better qualitative understanding of the physics than naive renormalization group methods. In particular I show that the simplest CORE computation yields a first-principles understanding of how the famous Haldane conjecture works for the case of the spin-1/2 and spin-1 HAF.
MOTIVATION TO SHARE HOSPITAL BUILDING DESIGN KNOWLEDGE BY INFORMATION TECHNOLOGY IN HONG KONG
Directory of Open Access Journals (Sweden)
Rita Yi Man LI
2010-06-01
Full Text Available Hospital building design is important as it is the place where bacteria and microorganisms concentrate. Poor ventilation system and layout traps disease causing pathogens, threatens the lives of many frontline workers such as doctors, nurses, and health care assistants. While design knowledge sharing by IT ensures a rapid knowledge sharing among designers from all over the world, what are their motivations? Few or no paper has studied this issue. This paper studies this base on 4 traditional motivation theories: Theory X, Theory Y, Reinforcement theory, Two factor theory. Results show that positive reinforcement theory and motivation factors in two factor theory provide better explanation.
Constraints on hypothetical counterexamples to the Casas-Alvero conjecture
Laterveer, Robert
2012-01-01
The Casas-Alvero conjecture states: if a complex univariate polynomial has a common root with each of its derivatives, then it has a unique root. We show that hypothetical counterexamples must have at least 5 different roots. The first case where the conjecture is not known is in degree 12. We study the case of degree 12, and more generally degree p+1, where p is a prime number. While we don't come closing to solving the conjecture in degree 12, we present several further constraints that counterexamples would have to satisfy.
Aspects of Quantum Mathematics Hitchin Connections and AJ Conjectures
DEFF Research Database (Denmark)
Lauridsen, Magnus Roed
We discuss two different areas related to -dimensional Topological Quantum Field Theory, namely geometric quantization and the AJ-conjecture in knot theory. First, we construct a Hitchin connection in geometric quantization with metaplectic correction of symplectic manifolds, and compare...... it to previous constructions. Second, we review the AJ-conjecture in knot theory, relating the coloured Jones polynomial and the A-polynomial. We reformulate this conjecture geometrically, drawing on geometric quantization of moduli spaces. Last, we use Faddeev's quantum dilogarithm to describe the asymptotic...
On the generalized lower bound conjecture for polytopes and spheres
Murai, Satoshi
2012-01-01
In 1971, McMullen and Walkup posed the following conjecture, which is called the generalized lower bound conjecture (GLBC): If $P$ is a simplicial $d$-polytope then its $h$-vector $(h_0,h_1,...,h_d)$ satisfies $h_0 \\leq h_1 \\leq ... \\leq h_{\\lfloor d/2 \\rfloor}$. Moreover, if $h_{r-1}=h_r$ for some $r \\leq d/2$ then $P$ can be triangulated without introducing simplices of dimension $\\leq d-r$. The first part of the conjecture was solved by Stanley in 1980 using the Hard Lefschetz theorem for toric varieties. In this paper, we give a proof of the remaining part of the conjecture. In addition, we generalize this property to a certain class of simplicial spheres, namely those admitting the weak Lefschetz property.
An algebro-geometric proof of Witten's conjecture
Kazarian, M. E.; Lando, S. K.
2007-10-01
We present a new proof of Witten's conjecture. The proof is based on the analysis of the relationship between intersection indices on moduli spaces of complex curves and Hurwitz numbers enumerating ramified coverings of the 2 -sphere.
On conjectures of Minkowski and Woods for $n = 9$
Indian Academy of Sciences (India)
LEETIKA KATHURIA; MADHU RAKA
2016-10-01
Let $\\mathbb{R}^n$ be the $n$-dimensional Euclidean space with $O$ as the origin. Let $\\wedge$ be a lattice of determinant 1 such that there is a sphere $\\mid X \\mid \\lt R$ which contains no point of $\\wedge$ other than $O$ and has $n$ linearly independent points of $\\wedge$ on its boundary. A well known conjecture in the geometry of numbers asserts that any closed sphere in $\\mathbb{R}^n$ of radius $\\sqrt{n/4}$ contains a point of $\\wedge$. This is known to be true for $n\\leq 8$. Here we prove a more general conjecture of Woods for $n = 9$ from which this conjecture follows in $\\mathbb{R}^9$. Together with a result of McMullen (J. Amer. Math. Soc. 18 (2005) 711–734), the long standing conjecture of Minkowski follows for $n = 9$.
Berry{close_quote}s conjecture and information theory
Energy Technology Data Exchange (ETDEWEB)
Jarzynski, C. [Theoretical Astrophysics, T-6, MS B288, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
1997-08-01
It is shown that, by applying a principle of information theory, one obtains Berry{close_quote}s conjecture regarding the high-lying quantal energy eigenstates of classically chaotic systems. {copyright} {ital 1997} {ital The American Physical Society}
A Conjecture on the Origin of Dark Energy
Institute of Scientific and Technical Information of China (English)
GAO Shan
2005-01-01
@@ A conjecture on the origin of the dark energy in our universe is proposed. The analysis indicates that the dark energy may originate from the quantum fluctuations of space-time limited in our universe.
Conjecturing and Generalization Process on The Structural Development
Ni'mah, Khomsatun; Purwanto; Bambang Irawan, Edy; Hidayanto, Erry
2017-06-01
This study aims to describe how conjecturing process and generalization process of structural development to thirty children in middle school at grade 8 in solving problems of patterns. Processing of the data in this study uses qualitative data analysis techniques. The analyzed data is the data obtained through direct observation technique, documentation, and interviews. This study based on research studies Mulligan et al (2012) which resulted in a five - structural development stage, namely prestructural, emergent, partial, structural, and advance. From the analysis of the data in this study found there are two phenomena that is conjecturing and generalization process are related. During the conjecturing process, the childrens appropriately in making hypothesis of patterns problem through two phases, which are numerically and symbolically. Whereas during the generalization of process, the childrens able to related rule of pattern on conjecturing process to another context.
Saari's Conjecture for the Collinear $n$-Body Problem
Diacu, Florin; Santoprete, Manuele
2009-01-01
In 1970 Don Saari conjectured that the only solutions of the Newtonian $n$-body problem that have constant moment of inertia are the relative equilibria. We prove this conjecture in the collinear case for any potential that involves only the mutual distances. Furthermore, in the case of homogeneous potentials, we show that the only collinear and non-zero angular momentum solutions are homographic motions with central configurations.
Gauge-flation and Cosmic No-Hair Conjecture
Maleknejad, A; Soda, Jiro
2011-01-01
Gauge-flation, inflation from non-Abelian gauge fields, was introduced in [1,2]. In this work, we study the cosmic no-hair conjecture in gauge-flation. Starting from Bianchi-type I cosmology and through analytic and numeric studies we demonstrate that the isotropic FLRW inflation is an attractor of the dynamics of the theory and that the anisotropies are damped within a few e-folds, in accord with the cosmic no-hair conjecture.
Upper bounds for prime gaps related to Firoozbakht's conjecture
Kourbatov, Alexei
2015-01-01
We study two kinds of conjectural bounds for the prime gap after the k-th prime $p_k$: (A) $p_{k+1} 9$. The upper bound (A) is equivalent to Firoozbakht's conjecture. We prove that (A) implies (B) with $b=1$; on the other hand, (B) with $b=1.17$ implies (A). We also give other sufficient conditions for (A) that have the form (B) with $b\\to1$ as $p_k\\to\\infty$.
The Generalized Effros-Hahn Conjecture for Groupoids
Ionescu, Marius
2008-01-01
The generalized Effros-Hahn conjecture for groupoid C*-algebras says that, if G is amenable, then every primitive ideal of the groupoid C*-algebra C*(G) is induced from a stability group. We prove that the conjecture is valid for all second countable amenable locally compact Hausdorff groupoids. Our results are a sharpening of previous work of Jean Renault and depend significantly on his results.
Constraints on Dark Energy Models from Weak Gravity Conjecture
Institute of Scientific and Technical Information of China (English)
CHEN Xi-Ming; LIU Jie; GONG Yun-Gui
2008-01-01
@@ We study the constraints on the dark energy model with constant equation of state parameter w = p/p and the holographic dark energy model by using the weak gravity conjecture. The combination of weak gravity conjecture and the observational data gives w < -0.7 at the 3σ confidence level. The holographic dark energy model realized by a scalar field is in swampland.
The Farrell-Jones Isomorphism Conjecture in K-Theory
Morteo, Marcelo Gomez
2012-01-01
We prove that the Farrell-Jones isomorphism conjecture for non connective K theory for a discrete group G and a coefficient ring R holds true if G belongs to the class of groups acting on trees under certain conditions on G and if R is either regular or hereditary, depending on the structure of G. It is known that these groups verify the isomorphism conjecture if finitely generated for any coefficient ring, but in this article G may not be finitely generated.
A proof of the Barát-Thomassen conjecture
DEFF Research Database (Denmark)
Bensmail, Julien; Harutyunyan, Ararat; Le, Tien Nam;
2017-01-01
The Barát-Thomassen conjecture asserts that for every tree T on m edges, there exists a constant kT such that every kT-edge-connected graph with size divisible by m can be edge-decomposed into copies of T. So far this conjecture has only been verified when T is a path or when T has diameter at mo...
The Secant Conjecture in the real Schubert calculus
Garcia-Puente, Luis; Hillar, Christopher J; del Campo, Abraham Martin; Ruffo, James; Sottile, Frank; Teitler, Zach
2010-01-01
We formulate the Secant Conjecture, which is a generalization of the Shapiro Conjecture for Grassmannians. It asserts that an intersection of Schubert varieties in a Grassmannian is transverse with all points real, if the flags defining the Schubert varieties are secant along disjoint intervals of a rational normal curve. We present both theoretical evidence for its validity and computational evidence obtained in an experiment using over one terahertz-year of computing, and we discuss some phenomena we observed in our data.
Directory of Open Access Journals (Sweden)
Deirdre Walsh
2015-10-01
This formative work has outlined key patient and stakeholder concerns regarding engagement with a technology enabled behavior change intervention in CR. Factors that inhibit and promote engagement have been explored using the COM-B framework. Motivational factors related to social interaction were deemed one of the integral aspects for engagement and adherence to PATHway. In terms of capability factors, technology ease- of-use was highlighted among patient and stakeholders as important for uptake and continued use. This project has received funding from the European Union’s Horizon 2020 Framework Programme for Research and Innovation Action under Grant Agreement no. 643491. PATHway: Technology enabled behavioural change as a pathway towards better self-management of CVD (www.pathway2health.eu
Irby, Thaddaeus
2011-01-01
This study examines the three generations comprising today's IT organizations to determine whether the Situational Leadership approach is effective in motivating this diverse work force to perform project-related tasks. Baby Boomer employees, Generation X employees, and Generation Y employees are the three generations actively employed in IT…
Motivating Children to Develop Their Science, Technology, Engineering, and Mathematics (STEM) Talent
Andersen, Lori
2013-01-01
Motivation in mathematics and science appears to be more important to STEM occupational choice than ability. Using the expectancy value model, parents may be able to recognize potential barriers to children's selection of a STEM occupation and take actions to help facilitate talent development. These are especially important for parents of…
Irby, Thaddaeus
2011-01-01
This study examines the three generations comprising today's IT organizations to determine whether the Situational Leadership approach is effective in motivating this diverse work force to perform project-related tasks. Baby Boomer employees, Generation X employees, and Generation Y employees are the three generations actively employed in IT…
Efe, Hülya Aslan; Baysal, Yunus Emre
2017-01-01
In line with the growing importance of use of education technologies in the field of education, teachers are increasingly expected to use education technologies in class environment and to provide students with appropriate environments and opportunities to use these technologies. This situation makes it necessary to investigate teachers'…
Mieszczak, Gina L.
2013-01-01
Organizations depend extensively on Information Technology professionals to drive and deliver technology solutions quickly, efficiently, and effectively to achieve business goals and profitability. It has been demonstrated that professionals with experience specific to the company are valuable assets, and their departure puts technology projects…
Directory of Open Access Journals (Sweden)
Mark Bussin
2015-02-01
Full Text Available Purpose: The world of work is evolving and the nature of relationships between knowledge workers and their employers has changed distinctly, leading to a change in the type of rewards they prefer. The nature of these preferences in the South African, industry-specific context is poorly understood. The purpose of this study was to deepen understanding of the reward preferences of Information technology (IT knowledge workers in South Africa, specifically as these relate to the attraction, retention and motivation of knowledge workers.Design: The research design included a quantitative, empirical and descriptive study of reward preferences, measured with a self-administered survey and analysed using non-parametric tests for variance between dependent and independent groups and non-parametric analysis of variance.Findings: This study found that there are specific reward preferences in knowledge workers in the IT sector in South Africa and that these preferences apply differently when related to the attraction, retention and motivation of employees. It identified the most important reward components in the competition for knowledge workers and also demonstrated that demographic characteristics play a statistically significant role in determining reward preferences.Practical implications: The study’s findings show that a holistic approach to total rewards is required, failing which, companies will find themselves facing increased turnover and jobhopping. Importantly, the study also highlights that different rewards need to form part of knowledge workers’ relationship with their employer in three different scenarios: attraction, retention and motivation.
MOTIVATION TO SHARE HOSPITAL BUILDING DESIGN KNOWLEDGE BY INFORMATION TECHNOLOGY IN HONG KONG
Li, Rita Yi Man; Rita PEIHUA Zhang
2010-01-01
Hospital building design is important as it is the place where bacteria and microorganisms concentrate. Poor ventilation system and layout traps disease causing pathogens, threatens the lives of many frontline workers such as doctors, nurses, and health care assistants. While design knowledge sharing by IT ensures a rapid knowledge sharing among designers from all over the world, what are their motivations? Few or no paper has studied this issue. This paper studies this base on 4 traditional ...
DEFF Research Database (Denmark)
are grappling with how to create motivating products, and as a primer for students who want a brief introduction to some of the relevant theories, findings and design interventions in these fields. The editor's introduction raises a number of issues encountered when we try to apply behavioural research......How can products be designed to change our habits for the better? What is some of the leading research that designers can draw on to create new systems that motivate people towards healthier behaviour? Designing Motivation is an edited collection of ‘industrialist cheat sheets’: 22 single......-page summaries of research articles relating to technology design, motivation, and behaviour change. Ranging across the fields of economics, sociology, design research and behavioural science, each summary draws out the design implications of the research. It is intended as a resource for designers who...
DEFF Research Database (Denmark)
are grappling with how to create motivating products, and as a primer for students who want a brief introduction to some of the relevant theories, findings and design interventions in these fields. The editor's introduction raises a number of issues encountered when we try to apply behavioural research......How can products be designed to change our habits for the better? What is some of the leading research that designers can draw on to create new systems that motivate people towards healthier behaviour? Designing Motivation is an edited collection of ‘industrialist cheat sheets’: 22 single......-page summaries of research articles relating to technology design, motivation, and behaviour change. Ranging across the fields of economics, sociology, design research and behavioural science, each summary draws out the design implications of the research. It is intended as a resource for designers who...
The mixed Schmidt conjecture in the theory of Diophantine approximation
Badziahin, Dzmitry; Velani, Sanju
2010-01-01
Let $\\mathcal{D}=(d_n)_{n=1}^\\infty$ be a bounded sequence of integers with $d_n\\ge 2$ and let $(i, j)$ be a pair of strictly positive numbers with $i+j=1$. We prove that the set of $x \\in \\RR$ for which there exists some constant $c(x) > 0$ such that \\[ \\max\\{|q|_\\DDD^{1/i}, \\|qx\\|^{1/j}\\} > c(x)/ q \\qquad \\forall q \\in \\NN \\] is one quarter winning (in the sense of Schmidt games). Thus the intersection of any countable number of such sets is of full dimension. In turn, this establishes the natural analogue of Schmidt's conjecture within the framework of the de Mathan-Teuli\\'e conjecture -- also known as the `Mixed Littlewood Conjecture'.
Can we observationally test the weak cosmic censorship conjecture?
Energy Technology Data Exchange (ETDEWEB)
Kong, Lingyao; Malafarina, Daniele; Bambi, Cosimo [Fudan University, Department of Physics, Center for Field Theory and Particle Physics, Shanghai (China)
2014-08-15
In general relativity, gravitational collapse of matter fields ends with the formation of a spacetime singularity, where the matter density becomes infinite and standard physics breaks down. According to the weak cosmic censorship conjecture, singularities produced in the gravitational collapse cannot be seen by distant observers and must be hidden within black holes. The validity of this conjecture is still controversial and at present we cannot exclude that naked singularities can be created in our Universe from regular initial data. In this paper, we study the radiation emitted by a collapsing cloud of dust and check whether it is possible to distinguish the birth of a black hole from the one of a naked singularity. In our simple dust model, we find that the properties of the radiation emitted in the two scenarios is qualitatively similar. That suggests that observational tests of the cosmic censorship conjecture may be very difficult, even in principle. (orig.)
A proof of Connelly's conjecture on 3-connected generic cycles
DEFF Research Database (Denmark)
Berg, Alex Rune; Jordán, Tibor
2001-01-01
A graph G = (V , E) is called a generic circuit if |E| = 2|V| - 2 and every X ⊂ V with 2 ≥ |X| ≥ |V| - 1 satisfies i(X) ≤ 2|X| - 3. Here i(X) denotes the number of edges induced by X. The operation extension subdivides an edge uw of a graph by a new vertex v and adds a new edge vz for some vertex z...... ≠ u, w. Connelly conjectured that every 3-connected generic circuit can be obtained from K4 by a sequence of extensions. We prove this conjecture. As a corollary, we also obtain a special case of a conjecture of Hendrickson on generically globally rigid graphs....
Shaker Al-Mohammadi; Emira Derbel
2014-01-01
In today’s globalised world, technologies have been embedded in every aspect of daily activities and discourses. The field of education made no exception and hence technologies have become an integral part of all educational systems worldwide, but with different levels and layers. The presence of information technology in English language teaching has brought about notable changes for teachers and learners alike. Accordingly, this paper investigates the impact of integrating information techn...
Orok-Duke, Orok Ekpo; Sackey, Jacob; Usiabulu, Michael; Bassey, Okpa Inah
2016-01-01
The purpose of this study was to find out the impact of incessant strike actions and industrial disputes in Cross River University of Technology and its effect on students' motivation to learning. Over the years, a considerable amount of effort has been put on ground in order to run the Cross River University of Technology devoid of financial…
The Andr\\'e-Oort Conjecture for Drinfeld Modular Varieties
Hubschmid, Patrik
2012-01-01
We consider the analogue of the Andr\\'e-Oort conjecture for Drinfeld modular varieties which was formulated by Breuer. We prove this analogue for special points with separable reflex field over the base field by adapting methods which were used by Klingler and Yafaev to prove the Andr\\'e-Oort conjecture under the generalized Riemann hypothesis in the classical case. Our result extends results of Breuer showing the correctness of the analogue for special points lying in a curve and for special points having a certain behaviour at a fixed set of primes.
Saari's Homographic Conjecture of the Three-Body Problem
Diacu, Florin; Perez-Chavela, Ernesto; Santoprete, Manuele
2009-01-01
Saari's homographic conjecture, which extends a classical statement proposed by Donald Saari in 1970, claims that solutions of the Newtonian $n$-body problem with constant configurational measure are homographic. In other words, if the mutual distances satisfy a certain relationship, the configuration of the particle system may change size and position but not shape. We prove this conjecture for large sets of initial conditions in three-body problems given by homogeneous potentials, including the Newtonian one. Some of our results are true for $n\\ge 3$.
Cosmic Censorship Conjecture in Kerr-Sen Black Hole
Gwak, Bogeun
2016-01-01
The validity of cosmic censorship conjecture for the Kerr-Sen black hole, which is a solution to the low-energy effective field theory for four-dimensional heterotic string theory, is investigated using charged particle absorption. When the black hole absorbs the particle, its charges are changed due to the conserved quantities of the particle. Changes in the black hole are constrained to the equation for the motion of the particle and are consistent with the laws of thermodynamics. Particle absorption increases the mass of the extremal Kerr-Sen black hole to more than its charges, so the black hole cannot be overcharged. Therefore, cosmic censorship conjecture is valid.
An analytical proof for Lehmer's totient conjecture using Mertens' theorems
2016-01-01
We make an analytical proof for Lehmer's totient conjecture. Lehmer conjectured that there is no solution for the congruence equation $n-1\\equiv 0~(mod~\\phi(n))$ with composite integers,$n$, where $\\phi(n)$ denotes Euler's totient function. He also showed that if the equation has any composite solutions, $n$ must be odd, square-free, and divisible by at least 7 primes. Several people have obtained conditions on values ,$n$, and number of square-free primes constructing $n$ if the equation can...
An analytical proof for Lehmer's totient conjecture using Mertens' theorems
Sabihi, Ahmad
2016-01-01
We make an analytical proof for Lehmer's totient conjecture. Lehmer conjectured that there is no solution for the congruence equation $n-1\\equiv 0~(mod~\\phi(n))$ with composite integers,$n$, where $\\phi(n)$ denotes Euler's totient function. He also showed that if the equation has any composite solutions, $n$ must be odd, square-free, and divisible by at least 7 primes. Several people have obtained conditions on values ,$n$, and number of square-free primes constructing $n$ if the equation can...
The Dirac Conjecture and the Non-uniqueness of Lagrangian
Wang, Yong-Long; Jiang, Hua; Lu, Wei-Tao; Pan, Hong-Zhe
2013-01-01
We prove the validity of the Dirac conjecture generally by adding the total time derivatives of all constraints to the Lagrangian step by step. It is worthy to state that the total time derivatives added to the original Lagrangian can turn up some constraints, and discover the symmetries hidden in the original Lagrangian. For a constrained system, the extended Hamiltonian $H_E$ contains more constraints, and shows more symmetries. We discuss the Cawley's counterexample, and prove it not a real one to the Dirac conjecture. And we offer an example, its extended Hamiltonian is better that its total Hamiltonian for its Lagrangian.
On the relation of Matrix theory and Maldacena conjecture
Silva, Pedro J.
1998-01-01
We report a sign that M(atrix) theory conjecture and the Maldacena conjecture for the case of D0-branes are compatible. Furthermore Maldacena point of view implies a restriction of range of validity in the DLCQ version of M(atrix) theory. The analysis is based on the uplift of type IIA supersymetric solution in the Maldacena approach to eleven dimensions, using a boost as a main tool. The relation is explored on both, IMF and DLCF versions of M(atrix) theory
BetterPoints: Motivating behaviour change using technology-driven incentivisation
Anne Lancaster
2015-01-01
Background Conference theme: Using behaviour change theory to create high-quality interventions and products. BetterPoints is a localised behaviour change system that uses incentivisation, recognition and social interaction – all driven by an innovative technology. Our main method of engagement is a proprietary smartphone app. The app is part of a powerful behaviour change technology platform that allows rapid customisation, massive reward flexibility and sophisticated reporting. This...
Holland, Denise D.; Piper, Randy T.
2014-01-01
Nobel laureates Schultz (1971) and Becker (1964, 1993) reinvigorated the analysis of education investments. Human capital investments that improve cognitive skills for elementary and secondary students have important economic implications. An interdisciplinary, 12-construct technology integration education (TIE) model was developed. The sample…
Rodriguez, Michael C.; Ooms, Ann; Montanez, Marcel; Yan, Yelena L.
2005-01-01
Online courses are appearing at a high rate, increasing the competitiveness of the distance learning market. Reluctance to invest in this area is due to cost and quality concerns. This study reports the findings of a survey of 700 professional and graduate education students regarding their comfort with technology, satisfaction with those…
The prime-pair conjectures of Hardy and Littlewood
Korevaar, J.
2012-01-01
By (extended) Wiener-Ikehara theory, the prime-pair conjectures are equivalent to simple pole-type boundary behavior of corresponding Dirichlet series. Under a weak Riemann-type hypothesis, the boundary behavior of weighted sums of the Dirichlet series can be expressed in terms of the behavior of ce
The remodeling conjecture and the Faber-Pandharipande formula
Bouchard, Vincent; Marchal, Olivier; Sulkowski, Piotr
2011-01-01
In this note, we prove that the free energies F_g constructed from the Eynard-Orantin topological recursion applied to the curve mirror to C^3 reproduce the Faber-Pandharipande formula for genus g Gromov-Witten invariants of C^3. This completes the proof of the remodeling conjecture for C^3.
Local Conjecturing Process in the Solving of Pattern Generalization Problem
Sutarto; Nusantara, Toto; Subanji; Sisworo
2016-01-01
This aim of this study is to describe the process of local conjecturing in generalizing patterns based on Action, Process, Object, Schema (APOS) theory. The subjects were 16 grade 8 students from a junior high school. Data collection used Pattern Generalization Problem (PGP) and interviews. In the first stage, students completed PGP; in the second…
A new proof of Faber's intersection number conjecture
Buryak, A
2009-01-01
We give a new proof of Faber's intersection number conjecture concerning the top intersections in the tautological ring of the moduli space of curves $\\M_g$. The proof is based on a very straightforward geometric and combinatorial computation with double ramification cycles.
Comments on the floating body and the hyperplane conjecture
Fresen, Daniel
2011-01-01
We provide upper and lower bounds on the logarithmic Hausdorff distance between an arbitrary convex body $K\\subset \\mathbb{R}^{d}$\\ and the convex floating body $K_{\\delta}$ inside $K$. We also discuss the hyperplane conjecture (the slicing problem) and provide a reformulation of this famous unsolved mystery in terms of the floating body.
Is the five-flow conjecture almost false?
Jacobsen, Jesper L
2010-01-01
The number of nowhere-zero Z_Q flows on a bridgeless graph G can be shown to be a polynomial in Q, defining the flow polynomial \\Phi_G(Q). According to Tutte's five-flow conjecture, \\Phi_G(5) > 0 for any G. A conjecture by Welsh that \\Phi_G(Q) has no real roots for Q \\in (4,\\infty) was recently disproved by Haggard, Pearce and Royle. These authors conjectured the same result for Q \\in [5,\\infty). We study the real and complex roots of \\Phi_G(Q) for a family of non-planar cubic graphs known as generalised Petersen graphs G(n,k). We show that the modified conjecture on real flow roots is also false, by exhibiting infinitely many real flow roots Q>5 within the class G(nk,k). In particular, we compute explicitly G(119,7) showing that it has real roots at Q\\approx 5.0000197675 and Q\\approx 5.1653424423. We moreover prove that the graph families G(6n,6) and G(7n,7) possess real flow roots that accumulate at Q=5 as n\\to\\infty; and that Q_c(7)\\approx 5.2352605291 is a non-isolated accumulation point of real zeros of ...
Game Show Mathematics: Specializing, Conjecturing, Generalizing, and Convincing
Lane, Catherine Pullin; Harkness, Shelly Sheats
2012-01-01
This article describes the authors' use of three game shows--"Survivor," "The Biggest Loser," and "Deal or No Deal?"--to determine to what degree students engaged in mathematical thinking: specializing, conjecturing, generalizing, and convincing (Burton, 1984). Student responses to the task of creating winning strategies to these shows were…
Counterexample to a Penrose inequality conjectured by Gibbons
Dain, Sergio; Yamada, Sumio
2010-01-01
We show that the Brill-Lindquist initial data provides a counterexample to a Riemannian Penrose inequality with charge conjectured by G. Gibbons. The observation illustrates a sub-additive characteristic of the area radii for the individual connected components of an outermost horizon as a lower bound of the ADM mass.
On the general elephant conjecture for Mori conic bundles
Prokhorov, Yu G
1996-01-01
Let $f:X\\to S$ be an extremal contraction from a threefolds with terminal singularities onto a surface (so called Mori conic bundle). We study some particular cases of such contractions: quotients of usual conic bundles and index two contractions. Assuming Reid's general elephants conjecture we also obtain a rough classification. We present many examples.
Min-Rank Conjecture for Log-Depth Circuits
Jukna, S
2010-01-01
A completion of an m-by-n matrix A with entries in {0,1,*} is obtained by setting all *-entries to constants 0 or 1. A system of semi-linear equations over GF(2) has the form Mx=f(x), where M is a completion of A and f:{0,1}^n --> {0,1}^m is an operator, the i-th coordinate of which can only depend on variables corresponding to *-entries in the i-th row of A. We conjecture that no such system can have more than 2^{n-c\\cdot mr(A)} solutions, where c>0 is an absolute constant and mr(A) is the smallest rank over GF(2) of a completion of A. The conjecture is related to an old problem of proving super-linear lower bounds on the size of log-depth boolean circuits computing linear operators x --> Mx. The conjecture is also a generalization of a classical question about how much larger can non-linear codes be than linear ones. We prove some special cases of the conjecture and establish some structural properties of solution sets.
Hamiltonian formulation of the Belinskii-Khalatnikov-Lifshitz conjecture
Ashtekar, A.; Henderson, A.; Sloan, D.J.A.
2011-01-01
The Belinskii, Khalatnikov, and Lifshitz conjecture [ V. A. Belinskii, I. M. Khalatnikov and E. M. Lifshitz Adv. Phys. 19 525 (1970)] posits that on approach to a spacelike singularity in general relativity the dynamics are well approximated by “ignoring spatial derivatives in favor of time
The stable moduli space of Riemann surfaces: Mumford's conjecture
DEFF Research Database (Denmark)
Madsen, I.; Weiss, Michael
2007-01-01
D. Mumford conjectured in "Towards an enumerative geometry of the moduli space of curves" that the rational cohomology of the stable moduli space of Riemann surfaces is a polynomial algebra generated by certain classes $\\kappa_i$ of dimension $2i$. For the purpose of calculating rational cohomolo...
The Bloch-Kato Conjecture and Galois Theory
Karagueuzian, Dikran; Miná\\vc, Ján
2010-01-01
We investigate the relations in Galois groups of maximal p-extensions of fields, the structure of their natural filtrations, and their relationship with the Bloch-Kato conjecture proved by Rost and Voevodsky with Weibel's patch. Our main focus is on the third degree, but we provide examples for all degrees.
Symmetric moment problems and a conjecture of Valent
Berg, C.; Szwarc, R.
2017-03-01
In 1998 Valent made conjectures about the order and type of certain indeterminate Stieltjes moment problems associated with birth and death processes which have polynomial birth and death rates of degree {p≥slant 3}. Romanov recently proved that the order is 1/p as conjectured. We prove that the type with respect to the order is related to certain multi-zeta values and that this type belongs to the interval which also contains the conjectured value. This proves that the conjecture about type is asymptotically correct as p\\to∞. The main idea is to obtain estimates for order and type of symmetric indeterminate Hamburger moment problems when the orthonormal polynomials P_n and those of the second kind Q_n satisfy P2n^2(0)∼ c_1n-1/β and Q2n-1^2(0)∼ c2 n-1/α, where 0proof of Romanov's Theorem that the order is 1/p. Bibliography: 19 titles.
Topological Hochschild homology and the Bass trace conjecture
DEFF Research Database (Denmark)
Berrick, A. J.; Hesselholt, Lars
2015-01-01
We use the methods of topological Hochschild homology to shed new light on groups satisfying the Bass trace conjecture. Factorization of the Hattori–Stallings rank map through the Bökstedt–Hsiang–Madsen cyclotomic trace map leads to Linnell's restriction on such groups. As a new consequence...
Motivations of Women Participating in a Technology-Based Social Entrepreneurship Program
Dzombak, Rachel; Mouakkad, Sally; Mehta, Khanjan
2016-01-01
Academic programs focused on engineering entrepreneurship are growing in number and popularity at American universities. However, the fields of engineering, entrepreneurship and technology-based entrepreneurship struggle to recruit and retain female students: a historic and endemic failure at obtaining gender-balanced participation. Understanding…
Wu, Tung-Ju; Tai, Yu-Nan
2016-01-01
Under the waves of the Internet and the trend of era, information technology is a door connecting to the world to generate the multiplier effect of learning. Students' learning should not be regarded as the tool to cope with school examinations. The frequent contact with computers, networks, and relevant information allow students enjoying the…
Fibonacci Numbers Revisited: Technology-Motivated Inquiry into a Two-Parametric Difference Equation
Abramovich, Sergei; Leonov, Gennady A.
2008-01-01
This article demonstrates how within an educational context, supported by the notion of hidden mathematics curriculum and enhanced by the use of technology, new mathematical knowledge can be discovered. More specifically, proceeding from the well-known representation of Fibonacci numbers through a second-order difference equation, this article…
Holland, Denise D.; Piper, Randy T.
2016-01-01
The technology integration education model is a 12 construct model that includes 8 primary constructs and 4 moderator constructs. By testing the relationships among two primary constructs (motivation and technological, pedagogical, and content knowledge competencies) and four moderator constructs (goals, feedback, task value, and self-regulation),…
A note on a conjecture of Graffiti%关于Graffiti的一个猜想
Institute of Scientific and Technical Information of China (English)
陈恬; 束金龙
2006-01-01
In this paper,we will give a very simpleproof of a conjecture of Graffiti. (WOW Conjecture 584) :Let T be a tree of order n with independence number α , thenλ1 ≤ 2 + α , where λ1 is the Laplacian speetralradius. ( Xiao -dong Zhang , On the two conjectures of Graffiti, Linear Algebra and its Applications , described all extremal treesthat attain the maximal Laplacian spectral radius and used theresults to show conjectures.
Class numbers of cyclic 2-extensions and Gross conjecture over Q
Institute of Scientific and Technical Information of China (English)
无
2010-01-01
The Gross conjecture over Q was first claimed by Aoki in 1991.However,the original proof contains too many mistakes and false claims to be considered as a serious proof.This paper is an attempt to find a sound proof of the Gross conjecture under the outline of Aoki.We reduce the conjecture to an elementary conjecture concerning the class numbers of cyclic 2-extensions of Q.
The mixed Ax-Lindemann theorem and its applications to the Zilber-Pink conjecture
Gao, Ziyang
2014-01-01
The Zilber-Pink conjecture is a common generalization of the Andre-Oort and the Mordell-Lang conjectures. In this dissertation, we study its sub-conjectures: Andre-Oort, which predicts that a subvariety of a mixed Shimura variety having dense intersection with the set of special points is special; a
Equivalence of ELSV and Bouchard-Mariño conjectures for r-spin Hurwitz numbers
Shadrin, S.; Spitz, L.; Zvonkine, D.
2015-01-01
We propose two conjectures on Hurwitz numbers with completed (r+1)-cycles, or, equivalently, on certain relative Gromov-Witten invariants of the projective line. The conjectures are analogs of the ELSV formula and of the Bouchard-Mariño conjecture for ordinary Hurwitz numbers. Our r-ELSV formula is
Lawlor, John; Marshall, Kevin; Tangney, Brendan
2016-01-01
It is generally accepted that intrinsic student motivation is a critical requirement for effective learning but formal learning in school places a huge reliance on extrinsic motivation to focus the learner. This reliance on extrinsic motivation is driven by the pressure on formal schooling to "deliver to the test." The experience of the…
A Proof of the Boyd-Carr Conjecture
Schalekamp, Frans; van Zuylen, Anke
2011-01-01
Determining the precise integrality gap for the subtour LP relaxation of the traveling salesman problem is a significant open question, with little progress made in thirty years in the general case of symmetric costs that obey triangle inequality. Boyd and Carr [3] observe that we do not even know the worst-case upper bound on the ratio of the optimal 2-matching to the subtour LP; they conjecture the ratio is at most 10/9. In this paper, we prove the Boyd-Carr conjecture. In the case that a fractional 2-matching has no cut edge, we can further prove that an optimal 2-matching is at most 10/9 times the cost of the fractional 2-matching.
Complex analysis conformal inequalities and the Bieberbach conjecture
Kythe, Prem K
2015-01-01
Complex Analysis: Conformal Inequalities and the Bieberbach Conjecture discusses the mathematical analysis created around the Bieberbach conjecture, which is responsible for the development of many beautiful aspects of complex analysis, especially in the geometric-function theory of univalent functions. Assuming basic knowledge of complex analysis and differential equations, the book is suitable for graduate students engaged in analytical research on the topics and researchers working on related areas of complex analysis in one or more complex variables. The author first reviews the theory of analytic functions, univalent functions, and conformal mapping before covering various theorems related to the area principle and discussing Löwner theory. He then presents Schiffer’s variation method, the bounds for the fourth and higher-order coefficients, various subclasses of univalent functions, generalized convexity and the class of a-convex functions, and numerical estimates of the coefficient problem. The boo...
Constraints on axion inflation from the weak gravity conjecture
Energy Technology Data Exchange (ETDEWEB)
Rudelius, Tom [Jefferson Physical Laboratory, Harvard University,Cambridge, MA 02138 (United States)
2015-09-08
We derive constraints facing models of axion inflation based on decay constant alignment from a string-theoretic and quantum gravitational perspective. In particular, we investigate the prospects for alignment and ‘anti-alignment’ of C{sub 4} axion decay constants in type IIB string theory, deriving a strict no-go result in the latter case. We discuss the relationship of axion decay constants to the weak gravity conjecture and demonstrate agreement between our string-theoretic constraints and those coming from the ‘generalized’ weak gravity conjecture. Finally, we consider a particular model of decay constant alignment in which the potential of C{sub 4} axions in type IIB compactifications on a Calabi-Yau three-fold is dominated by contributions from D7-branes, pointing out that this model evades some of the challenges derived earlier in our paper but is highly constrained by other geometric considerations.
Complete solution to a conjecture of Zhang-Liu-Zhou
Directory of Open Access Journals (Sweden)
Mostafa Tavakoli
2014-11-01
Full Text Available Let dn;m = 2n+1 and En;m be the graph obtained from a path Pdn;m+1 = v0v1:::vdn;m by joining each vertex of Kn by joining each vertex of Kn. Zhang, Liu and Zhou [On the maximal eccentric connectivity indices of graphs, Appl. Math. J. Chinese Univ., in press] conjectured that if dn;m > 3, then En;m is the graph with maximal eccentric connectivity ndex among all connected graph with n vertices and m edges. In this note, we prove this conjecture. Moreover, we present the graph with maximal eccentric connectivity index among the connected graphs with n vertices. Finally, the minimum of this graph invariant n the classes of tricyclic and tetracyclic graphs are computed.
Introduction to sofic and hyperlinear groups and Connes' embedding conjecture
Capraro, Valerio
2015-01-01
This monograph presents some cornerstone results in the study of sofic and hyperlinear groups and the closely related Connes' embedding conjecture. These notions, as well as the proofs of many results, are presented in the framework of model theory for metric structures. This point of view, rarely explicitly adopted in the literature, clarifies the ideas therein, and provides additional tools to attack open problems. Sofic and hyperlinear groups are countable discrete groups that can be suitably approximated by finite symmetric groups and groups of unitary matrices. These deep and fruitful notions, introduced by Gromov and Radulescu, respectively, in the late 1990s, stimulated an impressive amount of research in the last 15 years, touching several seemingly distant areas of mathematics including geometric group theory, operator algebras, dynamical systems, graph theory, and quantum information theory. Several long-standing conjectures, still open for arbitrary groups, are now settled for sofic or hyperlinear ...
The Baum-Connes conjecture for free orthogonal quantum groups
Voigt, Christian
2009-01-01
We prove an analogue of the Baum-Connes conjecture for free orthogonal quantum groups. More precisely, we show that these quantum groups have a $ \\gamma $-element and that $ \\gamma = 1 $. It follows that free orthogonal quantum groups are $ K $-amenable. We compute explicitly their $ K $-theory and deduce in the unimodular case that the corresponding reduced $ C^* $-algebras do not contain nontrivial idempotents. Our approach is based on the reformulation of the Baum-Connes conjecture by Meyer and Nest using the language of triangulated categories. An important ingredient is the theory of monoidal equivalence of compact quantum groups developed by Bichon, De Rijdt and Vaes. This allows us to study the problem in terms of the quantum group $ SU_q(2) $. The crucial part of the argument is a detailed analysis of the equivariant Kasparov theory of the standard Podle\\'s sphere.
Yang-Mills Theory and the ABC Conjecture
He, Yang-Hui; Probst, Malte; Read, James
2016-01-01
We establish a precise correspondence between the ABC Conjecture and N=4 super-Yang-Mills theory. This is achieved by combining three ingredients: (i) Elkies' method of mapping ABC-triples to elliptic curves in his demonstration that ABC implies Mordell/Faltings; (ii) an explicit pair of elliptic curve and associated Belyi map given by Khadjavi-Scharaschkin; and (iii) the fact that the bipartite brane-tiling/dimer model for a gauge theory with toric moduli space is a particular dessin d'enfant in the sense of Grothendieck. We explore this correspondence for the highest quality ABC-triples as well as large samples of random triples. The Conjecture itself is mapped to a statement about the fundamental domain of the toroidal compactification of the string realization of N=4 SYM.
Virus Structure: From Crick and Watson to a New Conjecture
Iorio, Alfredo
2007-01-01
We conjecture that certain patterns (scars), theoretically and numerically predicted to be formed by electrons arranged on a sphere to minimize the repulsive Coulomb potential (the Thomson problem) and experimentally found in spherical crystals formed by self-assembled polystyrene beads (an instance of the generalized Thomson problem), could be relevant to extend the classic Caspar and Klug construction for icosahedrally-shaped virus capsids. The main idea is that scars could be produced at an intermediate stage of the assembly of the virus capsids and the release of the bending energy present in scars into stretching energy could allow for a variety of non-spherical capsids' shapes. The conjecture can be tested in experiments on the assembly of artificial protein-cages where these scars should appear.
Amro, Hanan Jamal
2014-01-01
Demand for online learning has increased in recent years due to the convenience of course delivery. However, some students appear to have difficulties with online education resulting in lack of completion. The study utilized a quantitative approach with archival data and survey design. The factors of demographics, motivation, technology, and…
Amro, Hanan Jamal
2014-01-01
Demand for online learning has increased in recent years due to the convenience of course delivery. However, some students appear to have difficulties with online education resulting in lack of completion. The study utilized a quantitative approach with archival data and survey design. The factors of demographics, motivation, technology, and…
Kenar, Ismail; Köse, Mücahit; Demir, Halil Ibrahim
2016-01-01
In this research, determination of motivation of 5th grade students living in rural and urban environments towards science learning and their attitudes towards science-technology course is aimed. This research is conducted based on descriptive survey model. Samples are selected through teleological model in accordance with the aim of this…
Proof of the WARM whisker conjecture for neuronal connections
Holmes, Mark; Kleptsyn, Victor
2017-04-01
This paper is devoted to the study of the so-called WARM reinforcement models that are generalisations of Pólya's urn. We show that in the graph setting, once the exponent α of the reinforcement function is greater than 2, the stable and critical equilibria can be supported only on spanning forests, and once α > 25 , on spanning whisker forests. Thus, we prove the whisker forests conjecture from Hofstad et al. [Ann. Appl. Probab. 26(4), 2494-2539 (2016)].
On Howard's Conjecture in Heterogeneous Shear Flow Problem
Indian Academy of Sciences (India)
R G Shandil; Jagjit Singh
2003-11-01
Howard's conjecture, which states that in the linear instability problem of inviscid heterogeneous parallel shear flow growth rate of an arbitrary unstable wave must approach zero as the wave length decreases to zero, is established in a mathematically rigorous fashion for plane parallel heterogeneous shear flows with negligible buoyancy force $g \\ll 1$ (Miles J W, J. Fluid Mech. 10 (1961) 496–508), where is the basic heterogeneity distribution function).
On a supercongruence conjecture of Rodriguez-Villegas
McCarthy, Dermot
2012-01-01
In examining the relationship between the number of points over $\\mathbb{F}_p$ on certain Calabi-Yau manifolds and hypergeometric series which correspond to a particular period of the manifold, Rodriguez-Villegas identified numerically 22 possible supercongruences. We prove one of the outstanding supercongruence conjectures between a special value of a truncated generalized hypergeometric series and the $p$-th Fourier coefficient of a modular form.
On the first integral conjecture of Rene Thom
Cresson, Jacky; Daniilidis, Aris; Shiota, Masahiro
2007-01-01
More that half a century ago R. Thom asserted in an unpublished manuscript that, generically, vector fields on compact connected smooth manifolds without boundary can admit only trivial continuous first integrals. Though somehow unprecise for what concerns the interpretation of the word \\textquotedblleft generically\\textquotedblright, this statement is ostensibly true and is nowadays commonly accepted. On the other hand, the (few) known formal proofs of Thom's conjecture are all relying to th...
Melham's Conjecture on Odd Power Sums of Fibonacci Numbers
Sun, Brian Y.; Xie, Matthew H. Y.; Yang, Arthur L.B.
2015-01-01
Ozeki and Prodinger showed that the odd power sum of the first several consecutive Fibonacci numbers of even order is equal to a polynomial evaluated at certain Fibonacci number of odd order. We prove that this polynomial and its derivative both vanish at $1$, and will be an integer polynomial after multiplying it by a product of the first consecutive Lucas numbers of odd order. This presents an affirmative answer to a conjecture of Melham.
Regarding a Representation-Theoretic Conjecture of Wigderson
Moore, Cristopher
2010-01-01
We show that there exists a family of irreducible representations R_i (of finite groups G_i) such that, for any constant t, the average of R_i over t uniformly random elements g_1, ..., g_t of G_i has operator norm 1 with probability approaching 1 as i limits to infinity. This settles a conjecture of Wigderson in the negative.
A groupoid approach to L\\"uck's amenability conjecture
Kyed, David
2012-01-01
We prove that amenability of a discrete group is equivalent to dimension flatness of certain ring inclusions naturally associated with measure preserving actions of the group. This provides a group-measure space theoretic solution to a conjecture of L\\"uck stating that amenability of a group is characterized by dimension flatness of the inclusion of its complex group algebra into the associated von Neumann algebra.
Factorization Conjecture and the Open/Closed String Correspondence
Baumgartl, M; Shatashvili, S L; Baumgartl, Marcus; Sachs, Ivo; Shatashvili, Samson L.
2005-01-01
We present evidence for the factorization of the world-sheet path integrals for 2d conformal field theories on the disk into bulk and boundary contributions. This factorization is then used to reinterpret a shift in closed string backgrounds in terms of boundary deformations in background independent open string field theory. We give a proof of the factorization conjecture in the cases where the background is represented by WZW and related models.
Compact Lie groups: Euler constructions and generalized Dyson conjecture
Cacciatori, S L; Scotti, A
2012-01-01
In this paper we present a very general method to construct generalized Euler parameterizations for compact simple Lie groups w.r.t. maximally symmetrically embedded simple Lie groups. Our construction is based on a detailed analysis of the geometry of these groups, which moreover gives rise to an interesting connection with certain generalized Dyson integrals. In particular, we obtain a geometry based proof of the generalized Macdonald conjecture correspondent to the root systems associated to all irreducible symmetric spaces.
On Lehmer's Conjecture for Polynomials and for Elliptic Curves
Silverman, Joseph H
2010-01-01
A number of authors have proven explicit versions of Lehmer's conjecture for polynomials whose coefficients are all congruent to 1 modulo m. We prove a similar result for polynomials f(X) that are divisible in (Z/mZ)[X] by a polynomial of the form 1+X+...+X^n for some n > \\epsilon*deg(f). We also formulate and prove an analogous statement for elliptic curves.
Conjecture on the physical implications of the scale anomaly
Energy Technology Data Exchange (ETDEWEB)
Hill, Christopher T.; /Fermilab
2005-10-01
Murray Gell-Mann, after co-inventing QCD, recognized the interplay of the scale anomaly, the renormalization group, and the origin of the strong scale, {Lambda}{sub QCD}. I tell a story, then elaborate this concept, and for the sake of discussion, propose a conjecture that the physical world is scale invariant in the classical, {h_bar}, limit. This principle has implications for the dimensionality of space-time, the cosmological constant, the weak scale, and Planck scale.
Saari's conjecture for the restricted three-body problem
Roberts, G. E.; Melanson, L.
2007-03-01
Saari’s conjecture adapted to the restricted three-body problem is proven analytically using BKK theory. Specifically, we show that it is not possible for a solution of the planar, circular, restricted three-body problem to travel along a level curve of the amended potential function unless it is fixed at a critical point (one of the five libration points.) Due to the low dimension of the problem, our proof does not rely on the use of a computer.
Eternal Chaotic Inflation is Prohibited by Weak Gravity Conjecture
Huang, Qing-Guo; Wang, Yi
2007-01-01
We investigate whether the eternal chaotic inflation can be achieved when the weak gravity conjecture is taken into account. We show that even the assisted chaotic inflation with potential $\\lambda\\phi^4$ or $m^2\\phi^2$ can not be eternal. The effective field theory description for the inflaton field breaks down before inflation reaches the eternal regime. We also find that the total number of e-folds is still bounded by the inflationary entropy for the assisted inflation.
The History of the Total Chromatic Number Conjecture
Shahmohamad, Hossein
2011-01-01
The total chromatic number conjecture which has appeared in a few hundred articles and in numerous books thus far is now one of the classic mathematical unsolved problems. It appears that many authors coincidentally have attributed it to Professor M. Behzad and/or to Professor V. G. Vizing. Eventually after four decades, Professor A. Soifer investigated the origin of this conjecture; published his findings in The Mathematical Coloring Book - 2009; and stated that, "In my opinion this unquestionably merits the joint credit to Vizing and Behzad." After checking all the arguments presented and the blames cited, I decided to investigate the controversy stated in this book on my own. My findings which are presented in this report specifically signify the following two points. - M. Behzad is the sole author of the Total Chromatic Number Conjecture. - The wrong referrals provided by numerous authors over the last forty four years, to indicate Vizing's authorship, must be brought to the attention of the authors and r...
Graph theory favorite conjectures and open problems 1
Hedetniemi, Stephen; Larson, Craig
2016-01-01
This is the first in a series of volumes, which provide an extensive overview of conjectures and open problems in graph theory. The readership of each volume is geared toward graduate students who may be searching for research ideas. However, the well-established mathematician will find the overall exposition engaging and enlightening. Each chapter, presented in a story-telling style, includes more than a simple collection of results on a particular topic. Each contribution conveys the history, evolution, and techniques used to solve the authors’ favorite conjectures and open problems, enhancing the reader’s overall comprehension and enthusiasm. The editors were inspired to create these volumes by the popular and well attended special sessions, entitled “My Favorite Graph Theory Conjectures," which were held at the winter AMS/MAA Joint Meeting in Boston (January, 2012), the SIAM Conference on Discrete Mathematics in Halifax (June,2012) and the winter AMS/MAA Joint meeting in Baltimore(January, 2014). In...
What is the magnetic Weak Gravity Conjecture for axions
Energy Technology Data Exchange (ETDEWEB)
Hebecker, Arthur; Henkenjohann, Philipp [Institute for Theoretical Physics, University of Heidelberg (Germany); Witkowski, Lukas T. [APC, Universite Paris 7, CNRS/IN2P3, CEA/IRFU, Obs. de Paris, Sorbonne Paris Cite, Paris (France)
2017-03-15
The electric Weak Gravity Conjecture demands that axions with large decay constant f couple to light instantons. The resulting large instantonic corrections pose problems for natural inflation. We explore an alternative argument based on the magnetic Weak Gravity Conjecture for axions, which we try to make more precise. Roughly speaking, it demands that the minimally charged string coupled to the dual 2-form-field exists in the effective theory. Most naively, such large-f strings curve space too much to exist as static solutions, thus ruling out large-f axions. More conservatively, one might allow non-static string solutions to play the role of the required charged objects. In this case, topological inflation would save the superplanckian axion. Furthermore, a large-f axion may appear in the low-energy effective theory based on two subplanckian axions in the UV. The resulting effective string is a composite object built from several elementary strings and domain walls. It may or may not satisfy the magnetic Weak Gravity Conjecture depending on how strictly the latter is interpreted and on the cosmological dynamics of this composite object, which remain to be fully understood. Finally, we recall that large-field brane inflation is naively possible in the codimension-one case. We show how string-theoretic back-reaction closes this apparent loophole of large-f (non-periodic) pseudo-axions. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Weak Gravity Conjecture in AdS/CFT
Nakayama, Yu
2015-01-01
We study implications of the weak gravity conjecture in the AdS/CFT correspondence. Unlike in Minkowski spacetime, AdS spacetime has a physical length scale, so that the conjecture must be generalized with an additional parameter. We discuss possible generalizations and translate them into the language of dual CFTs, which take the form of inequalities involving the dimension and charge of an operator as well as the current and energy-momentum tensor central charges. We then test these inequalities against various CFTs to see if they are universally obeyed by all the CFTs. We find that certain CFTs, such as supersymmetric QCDs, do not satisfy them even in the large $N$ limit. This does not contradict the conjecture in AdS spacetime because the theories violating them are either unlikely or unclear to have weakly coupled gravitational descriptions, but it suggests that the CFT inequalities obtained here by naive translations do not apply beyond the regime in which weakly coupled gravitational descriptions are a...
Shuhatovich, Olga M; Sharman, Mathilde P; Mirabal, Yvette N; Earle, Nan R; Follen, Michele; Basen-Engquist, Karen
2005-12-01
In order to improve recruitment for cervical cancer screening trials, it is necessary to analyze the effectiveness of recruitment strategies used in current trials. A trial to test optical spectroscopy for the diagnosis of cervical neoplasia recruited 1000 women from the community; the trial evaluated the emerging technology against Pap smears and colposcopically directed biopsies for cervical dysplasia. We have examined women's reasons for participating as well as the effectiveness and efficiency for each recruitment strategy. Reasons for participation were identified and compared between trials. The recruitment method that resulted in the most contacts was newspaper reportorial coverage and advertising, followed by family and friends, then television news coverage. The most cost-effective method for finding eligible women who attend the research appointment is word of mouth from a family member or friend. Recommendations are given for maximizing the efficiency of recruitment for cervical cancer screening trials.
Energy Technology Data Exchange (ETDEWEB)
Cui, Helen H [Los Alamos National Laboratory
2011-01-18
Through discussion the conference aims to: (1) Identify core components of a comprehensive global biosurveillance capability; (2) Determine the scientific and technical bases to support such a program; (3) Explore the improvement in biosurveillance to enhance regional and global disease outbreak prediction; (4) Recommend an engagement approach to establishing an effective international community and regional or global network; (5) Propose implementation strategies and the measures of effectiveness; and (6) Identify the challenges that must be overcome in the next 3-5 years in order to establish an initial global biosurveillance capability that will have significant positive impact on BioNP as well as public health and/or agriculture. There is also a look back at the First Biothreat Nonproliferation Conference from December 2007. Whereas the first conference was an opportunity for problem solving to enhance and identify new paradigms for biothreat nonproliferation, this conference is moving towards integrated comprehensive global biosurveillance. Main reasons for global biosurveillance are: (1) Rapid assessment of unusual disease outbreak; (2) Early warning of emerging, re-emerging and engineered biothreat enabling reduced morbidity and mortality; (3) Enhanced crop and livestock management; (4) Increase understanding of host-pathogen interactions and epidemiology; (5) Enhanced international transparency for infectious disease research supporting BWC goals; and (6) Greater sharing of technology and knowledge to improve global health.
FUTURE ENGINEER TRAINING: MOTIVATING TECHNIQUES
2016-01-01
The motivating techniques for training future engineer are proposed. Intrinsic and extrinsic motivations in professional training have been analyzed. The peculiarities of the formation process of students’ motivation in learning language at non-language universities have been systematized. Heuristic training technology based on students’ motivation to cognitive research has been implemented.
McDonald, Angelic P
2009-01-01
The radiologic career field has undergone radical changes in technology, regulatory compliance, and customer expectation.These changes often require dramatic alterations to processes,which can break down communication, create stress, and have a negative effect on department productivity. Motivation itself is a frequently analyzed and reported topic in professional publications. For this purpose, this literature review specifically researches motivation as identified by radiology administrators through Radiology Management. Three key elements surfaced as those with the most impact: (1) motivation is an intrinsic factor which can be influenced but not created, (2) clear attainable goals are an essential component of motivation,and (3) motivation begins with identification of employee needs.
The weak 3-flow conjecture and the weak circular flow
DEFF Research Database (Denmark)
Thomassen, Carsten
2012-01-01
We show that, for each natural number k>1, every graph (possibly with multiple edges but with no loops) of edge-connectivity at least 2k2+k has an orientation with any prescribed outdegrees modulo k provided the prescribed outdegrees satisfy the obvious necessary conditions. For k=3 the edge-conn...... proposed in 2006 by Bárat and Thomassen when restricted to stars. Finally, it is the currently strongest partial result on the (2+ϵ)-flow conjecture by Goddyn and Seymour....
Quantum hoop conjecture: Black hole formation by particle collisions
Energy Technology Data Exchange (ETDEWEB)
Casadio, Roberto, E-mail: casadio@bo.infn.it [Dipartimento di Fisica e Astronomia, Università di Bologna, via Irnerio 46, 40126 Bologna (Italy); I.N.F.N., Sezione di Bologna, viale Berti Pichat 6/2, 40127 Bologna (Italy); Micu, Octavian, E-mail: octavian.micu@spacescience.ro [Institute of Space Science, Bucharest, P.O. Box MG-23, RO-077125 Bucharest-Magurele (Romania); Scardigli, Fabio, E-mail: fabio@phys.ntu.edu.tw [Dipartimento di Matematica, Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milano (Italy); Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502 (Japan)
2014-05-01
We address the issue of (quantum) black hole formation by particle collision in quantum physics. We start by constructing the horizon wave-function for quantum mechanical states representing two highly boosted non-interacting particles that collide in flat one-dimensional space. From this wave-function, we then derive a probability that the system becomes a black hole as a function of the initial momenta and spatial separation between the particles. This probability allows us to extend the hoop conjecture to quantum mechanics and estimate corrections to its classical counterpart.
On a conjecture about inverse domination in graphs
DEFF Research Database (Denmark)
Frendrup, Allan; Henning, Michael A.; Randerath, Bert
Let G = (V,E) be a graph with no isolated vertex. A classical observation in domination theory is that if D is a minimum dominating set of G, then V \\D is also a dominating set of G. A set D′ is an inverse dominating set of G if D′ is a dominating set of G and D′ ⊆ V \\D for some minimum dominating...... domination number of G is at most the independence number of G. We prove this conjecture for special families of graphs, including claw-free graphs, bipartite graphs, split graphs, very well covered graphs, chordal graphs and cactus graphs....
On a Conjecture about Inverse Domination in Graphs
DEFF Research Database (Denmark)
Frendrup, Allan; Henning, Michael A.; Randerath, Bert
2010-01-01
Let G = (V, E) be a graph with no isolated vertex. A classical observation in domination theory is that if D is a minimum dominating set of G, then V \\ D is also a dominating set of G. A set D' is an inverse dominating set of G if D' is a dominating set of G and D' subset of V \\ D for some minimum...... domination number of G is at most the independence number of G. We prove this conjecture for special families of graphs, including claw-free graphs, bipartite graphs, split graphs, very well covered graphs, chordal graphs and cactus graphs....
The stable moduli space of Riemann surfaces: Mumford's conjecture
DEFF Research Database (Denmark)
Madsen, I.; Weiss, Michael
2007-01-01
D. Mumford conjectured in "Towards an enumerative geometry of the moduli space of curves" that the rational cohomology of the stable moduli space of Riemann surfaces is a polynomial algebra generated by certain classes $\\kappa_i$ of dimension $2i$. For the purpose of calculating rational cohomology......, one may replace the stable moduli space of Riemann surfaces by $B\\Gamma_{\\infty}$, where $\\Gamma_\\infty$ is the group of isotopy classes of automorphisms of a smooth oriented connected surface of ``large'' genus. Tillmann's theorem that the plus construction makes $B\\Gamma_{\\infty}$ into an infinite...
The quantum chaos conjecture and generalized continued fractions
Pustyl'nikov, L. D.
2003-04-01
The proof of the quantum chaos conjecture is given for a class of systems including as a special case the model of a rotating particle under the action of periodic impulse perturbations. (The distribution of the distances between adjacent energy levels is close to the Poisson distribution and differs from it by terms of the third order of smallness.) The proof reduces to a result in number theory on the distribution of the distances between adjacent fractional parts of values of a polynomial, while the estimate of the remainder term is based on the new theory of generalized continued fractions for vectors.
Holomorphic Morse inequalities and the Green-Griffiths-Lang conjecture
Demailly, Jean-Pierre
2010-01-01
The goal of this work is to study the existence and properties of non constant entire curves f drawn in a complex irreducible n-dimensional variety X, and more specifically to show that they must satisfy certain global algebraic or differential equations as soon as X is projective of general type. By means of holomorphic Morse inequalities and a probabilistic analysis of the cohomology of jet spaces, we are able to reach a significant step towards a generalized version of the Green-Griffiths-Lang conjecture.
Remarks on S. Lang's conjecture over function fields
Moriwaki, A
1994-01-01
In this short note, we will show the following weak evidence of S. Lang conjecture over function fields. Let f : X ---> Y be a projective and surjective morphism of algebraic varieties over an algebraically closed field k of characteristic zero, whose generic fiber is geometrically irreducible and of general type. If f is not birationally trivial, then there are countably many proper closed varieties { Z_i } of X such that every quasi-section of f is contained in the union of Z_i.
On a problem in simultaneous Diophantine approximation: Schmidt's conjecture
Badziahin, Dzmitry; Velani, Sanju
2010-01-01
For any $i,j \\ge 0$ with $i+j =1$, let $\\bad(i,j)$ denote the set of points $(x,y) \\in \\R^2$ for which $ \\max \\{\\|qx\\|^{1/i}, \\|qy\\|^{1/j} \\} > c/q $ for all $ q \\in \\N $. Here $c = c(x,y)$ is a positive constant. Our main result implies that any finite intersection of such sets has full dimension. This settles a conjecture of Wolfgang M. Schmidt in the theory of simultaneous Diophantine approximation.
Conjecture and hypothesis: The importance of reality checks
Directory of Open Access Journals (Sweden)
David Deamer
2017-03-01
Full Text Available In origins of life research, it is important to understand the difference between conjecture and hypothesis. This commentary explores the difference and recommends alternative hypotheses as a way to advance our understanding of how life can begin on the Earth and other habitable planets. As an example of how this approach can be used, two conditions have been proposed for sites conducive to the origin of life: hydrothermal vents in salty seawater, and fresh water hydrothermal fields associated with volcanic landmasses. These are considered as alternative hypotheses and the accumulating weight of evidence for each site is described and analyzed.
Proofs of two conjectures on ternary weakly regular bent functions
Helleseth, Tor; Hollmann, Henk D. L.; Kholosha, Alexander; Wang, Zeying; Xiang, Qing
2008-01-01
We study ternary monomial functions of the form $f(x)=\\Tr_n(ax^d)$, where $x\\in \\Ff_{3^n}$ and $\\Tr_n: \\Ff_{3^n}\\to \\Ff_3$ is the absolute trace function. Using a lemma of Hou \\cite{hou}, Stickelberger's theorem on Gauss sums, and certain ternary weight inequalities, we show that certain ternary monomial functions arising from \\cite{hk1} are weakly regular bent, settling a conjecture of Helleseth and Kholosha \\cite{hk1}. We also prove that the Coulter-Matthews bent functions are weakly regular.
Graph Edge Coloring Vizing's Theorem and Goldberg's Conjecture
Stiebitz, Michael; Toft, Bjarne; Favrholdt, Lene M
2012-01-01
Features recent advances and new applications in graph edge coloring Reviewing recent advances in the Edge Coloring Problem, Graph Edge Coloring: Vizing's Theorem and Goldberg's Conjecture provides an overview of the current state of the science, explaining the interconnections among the results obtained from important graph theory studies. The authors introduce many new improved proofs of known results to identify and point to possible solutions for open problems in edge coloring. The book begins with an introduction to graph theory and the concept of edge coloring. Subsequent chapters explor
Knowledge space theory and union-closed sets conjecture
Directory of Open Access Journals (Sweden)
Chatchawan Panraksa
2016-08-01
Full Text Available The knowledge space theory provides a framework for knowledge management. One of major problems is to find core information for a body of knowledge. Union closed set conjecture, if true, guarantees that for a given knowledge space, there is an information that is linked to at least half of the knowledge units. This paper deals with a variant problem, where the knowledge space is also a topological space and possibly infinite. We prove that there is a point belonging to as many open sets as of the topological space itself.
On a conjecture of compatibility of multi-states characters
Habib, Michel
2011-01-01
Perfect phylogeny consisting of determining the compatibility of a set of characters is known to be NP-complete. We propose in this article a conjecture on the necessary and sufficient conditions of compatibility: Given a set $\\mathcal{C}$ of $r$-states full characters, there exists a function $f(r)$ such that $\\mathcal{C}$ is compatible iff every set of $f(r)$ characters of $\\mathcal{C}$ is compatible. Some previous work showed that $f(2)=2$, $f(3)=3$ and $f(r) \\ge r-1$. Gusfield et al. 09 conjectured that $f(r) = r$ for any $r \\ge 2$. In this paper, we present an example showing that $f(4) \\ge 5$ and then a closure operation for chordal sandwich graphs. The later problem is a common approach of perfect phylogeny. This operation can be the first step to simplify the problem before solving some particular cases $f(4), f(5), ... $, and determining the function $f(r)$.
A Counterexample to a Generalized Saari's Conjecture with a Continuum of Central Configurations
Santoprete, Manuele
2009-01-01
In this paper we show that in the $n$-body problem with harmonic potential one can find a continuum of central configurations for $n=3$. Moreover we show a counterexample to an interpretation of Jerry Marsden Generalized Saari's conjecture. This will help to refine our understanding and formulation of the Generalized Saari's conjecture, and in turn it might provide insight in how to solve the classical Saari's conjecture for $n\\geq 4$.
On the coefficient conjecture of Clunie and Sheil-Small on univalent harmonic mappings
Indian Academy of Sciences (India)
S Ponnusamy; A Sairam Kaliraj
2015-08-01
In this paper, we first prove the coefficient conjecture of Clunie and Sheil-Small for a class of univalent harmonic functions which includes functions convex in some direction. Next, we prove growth and covering theorems and some related results. Finally, we propose two conjectures, an affirmative answer to one of which would then imply, for example, a solution to the conjecture of Clunie and Sheil-Small.
Motivated information processing in organizational teams: Progress, puzzles, and prospects
Nijstad, B.A.; de Dreu, C.K.W.
2012-01-01
Much of the research into group and team functioning looks at groups that perform cognitive tasks, such as decision making, problem solving, and innovation. The Motivated Information Processing in Groups Model (MIP-G; De Dreu, Nijstad, & Van Knippenberg, 2008) conjectures that information processing
Motivated information processing in organizational teams: Progress, puzzles, and prospects
Nijstad, B.A.; de Dreu, C.K.W.
2012-01-01
Much of the research into group and team functioning looks at groups that perform cognitive tasks, such as decision making, problem solving, and innovation. The Motivated Information Processing in Groups Model (MIP-G; De Dreu, Nijstad, & Van Knippenberg, 2008) conjectures that information processing
A holographic perspective on Gubser-Mitra conjecture
Buchel, A
2005-01-01
We point out an elementary thermodynamics fact that whenever the specific heat of a system is negative, the speed of sound in such a media is imaginary. The latter observation presents a proof of Gubser-Mitra conjecture on the relation between dynamical and thermodynamic instabilities for gravitational backgrounds with a translationary invariant horizon, provided such geometries can be interpreted as holographic duals to finite temperature gauge theories. It further identifies a tachyonic mode of the Gubser-Mitra instability (the lowest quasinormal mode of the corresponding horizon geometry) as a holographic dual to a sound wave in a dual gauge theory. As a specific example, we study sound wave propagation in Little String Theory (LST) compactified on a two-sphere. We find that at high energies (for temperatures close to the LST Hagedorn temperature) the speed of sound is purely imaginary. This implies that the lowest quasinormal mode of the finite temperature Maldacena-Nunez background is tachyonic.
Embeddings, immersions and the Bartnik quasi-local mass conjectures
Anderson, Michael T
2016-01-01
Given a Riemannian 3-ball $(B, g)$ of non-negative scalar curvature, Bartnik conjectured that $(B, g)$ admits an asymptotically flat (AF) extension (without horizons) of the least possible ADM mass, and that such a mass-minimizer is an AF solution to the static vacuum Einstein equations, uniquely determined by natural geometric conditions on the boundary data of $(B, g)$. We prove the validity of the second statement, i.e. such mass-minimizers, if they exist, are indeed AF solutions of the static vacuum equations. On the other hand, we prove that the first statement is not true in general; there is a rather large class of bodies $(B, g)$ for which a minimal mass extension does not exist.
Hoop Conjecture and Black Holes on a Brane
Nakamura, K; Mishima, T; Nakamura, Kouji; Nakao, Ken-ichi; Mishima, Takeshi
2003-01-01
The initial data of gravity for a cylindrical matter distribution confined to a brane are studied in the framework of the single-brane Randall-Sundrum scenario. In this scenario, the 5-dimensional nature of gravity appears in the short-range gravitational interaction. We find that a sufficiently thin configuration of matter leads to the formation of a marginal surface, even if the configuration is infinitely long. This implies that the hoop conjecture proposed by Thorne does not hold on the brane: Even if a mass $M$ does not become compacted into a region whose circumference ${\\cal C}$ in every direction satisfies ${\\cal C}> 4\\pi GM$, black holes with horizons can form in the Randall-Sundrum scenario.
Hoop Conjecture and Cosmic Censorship in the Brane-World
Nakao, K; Mishima, T; Nakao, Ken-ichi; Nakamura, Kouji; Mishima, Takashi
2003-01-01
The initial data of gravity for a cylindrical matter distribution confined on the brane is studied in the framework of the single brane Randall-Sundrum scenario. In this scenario, 5-dimensional aspect of gravity appears in the short range gravitational interaction. We found that the sufficiently thin configuration of matter leads to the formation of the marginal surface even if the configuration is infinitely long. This means that the hoop conjecture proposed by Thorne does not hold in the Randall-Sundrum scenario; Even if a mass $M$ does not get compacted into a region whose circumference in every direction is ${\\cal C}\\le 4\\pi GM$, black holes with horizons can form in the Randall-Sundrum scenario.
Tryon's conjecture and Energy and momentum of Bianchi Type Universes
Mishra, Prajyot Kumar; Pattanayak, Pradosh Ranjan; Tripathy, Sunil Kumar
2016-01-01
The energy and momentum of the Bianchi type $III$ universes are obtained using different prescriptions for the energy-momentum complexes in the framework of General Relativity. The energy and momentum of the Bianchi $III$ universe is found to be zero for the M\\o{}ller prescription. For all other prescriptions the energy and momentum vanish when the metric parameter $h$ vanishes. In an earlier work, Tripathy et al. \\cite{SKT15} have obtained the energy and momentum of Bianchi $VI_h$ metric and found that the energy of the Universe vanish only for $h=-1$. This result raised a question: why this specific choice?. We explored the Tryon's conjecture that 'the Universe must have a zero net value for all conserved quantities' to get some ideas on the specific values of this parameter for Bianchi type Universes.
Sums of hermitian squares and the BMV conjecture
Klep, Igor
2007-01-01
Recently Lieb and Seiringer showed that the Bessis-Moussa-Villani conjecture from quantum physics can be restated in the following purely algebraic way: The sum of all words in two positive semidefinite matrices where the number of each of the two letters is fixed is always a matrix with nonnegative trace. We show that this statement holds if the words are of length at most 13. This has previously been known only up to length 7. In our proof, we establish a connection to sums of hermitian squares of polynomials in noncommuting variables and to semidefinite programming. As a by-product we obtain an example of a real polynomial in two noncommuting variables having nonnegative trace on all symmetric matrices of the same size, yet not being a sum of hermitian squares and commutators.
Representations of unipotent groups over local fields and Gutkin's conjecture
Boyarchenko, Mitya
2010-01-01
Let F be a finite field or a local field of any characteristic. If A is a finite dimensional associative nilpotent algebra over F, the set 1+A of all formal expressions of the form 1+x, where x ranges over the elements of A, is a locally compact group with the topology induced by the standard one on F and the multiplication given by (1+x)(1+y)=1+(x+y+xy). We prove a result conjectured by Eugene Gutkin in 1973: every unitary irreducible representation of 1+A can be obtained by unitary induction from a 1-dimensional unitary character of a subgroup of the form 1+B, where B is an F-subalgebra of A. In the case where F is local and nonarchimedean we also establish an analogous result for smooth irreducible representations of 1+A over the field of complex numbers and show that every such representation is admissible and carries an invariant Hermitian inner product.
A Holographic Entanglement Entropy Conjecture for General Spacetimes
Sanches, Fabio
2016-01-01
We present a natural generalization of holographic entanglement entropy proposals beyond the scope of AdS/CFT by anchoring extremal surfaces to holographic screens. Holographic screens are a natural extension of the AdS boundary to arbitrary spacetimes and are preferred codimension 1 surfaces from the viewpoint of the covariant entropy bound. Screens have a unique preferred foliation into codimension 2 surfaces called leaves. Our proposal is to find the areas of extremal surfaces achored to the boundaries of regions in leaves. We show that the properties of holographic screens are sufficient to prove, under generic conditions, that extremal surfaces anchored in this way always lie within a causal region associated with a given leaf. Within this causal region, a maximin construction similar to that of Wall proves that our proposed quantity satisfies standard properties of entanglement entropy like strong subadditivity. We conjecture that our prescription computes entanglement entropies in quantum states that h...
Spectral Duality in Integrable Systems from AGT Conjecture
Mironov, A; Zenkevich, Y; Zotov, A
2012-01-01
We describe relationships between integrable systems with N degrees of freedom arising from the AGT conjecture. Namely, we prove the equivalence (spectral duality) between the N-cite Heisenberg spin chain and a reduced gl(N) Gaudin model both at classical and quantum level. The former one appears on the gauge theory side of the AGT relation in the Nekrasov-Shatashvili (and further the Seiberg-Witten) limit while the latter one is natural on the CFT side. At the classical level, the duality transformation relates the Seiberg-Witten differentials and spectral curves via a bispectral involution. The quantum duality extends this to the equivalence of the corresponding Baxter-Schrodinger equations (quantum spectral curves). This equivalence generalizes both the spectral self-duality between the 2x2 and NxN representations of the Toda chain and the famous AHH duality.
The swampland conjecture and F-term axion monodromy inflation
Blumenhagen, Ralph; Valenzuela, Irene; Wolf, Florian
2017-07-01
We continue the investigation of F-term axion monodromy inflation in string theory, while seriously taking the issue of moduli stabilization into account. For a number of closed and open string models, we show that they suffer from serious control issues once one is trying to realize trans-Planckian field excursions. More precisely, the flux tuning required to delay the logarithmic scaling of the field distance to a trans-Planckian value cannot be done without leaving the regime where the employed effective supergravity theory is under control. Our findings are consistent with the axionic extension of the Refined Swampland Conjecture, stating that in quantum gravity the effective theory breaks down for a field excursion beyond the Planck scale. Our analysis suggests that models of F-term axion monodromy inflation with a tensor-to-scalar ratio r ≥ O(10-3) cannot be parametrically controlled.
Notes on the proof of the KKV conjecture
Pandharipande, R
2014-01-01
The Katz-Klemm-Vafa conjecture expresses the Gromov-Witten theory of K3 surfaces (and K3-fibred 3-folds in fibre classes) in terms of modular forms. Its recent proof gives the first non-toric geometry in dimension greater than 1 where Gromov-Witten theory is exactly solved in all genera. We survey the various steps in the proof. The MNOP correspondence and a new Pairs/Noether-Lefschetz correspondence for K3-fibred 3-folds transform the Gromov-Witten problem into a calculation of the full stable pairs theory of a local K3-fibred 3-fold. The stable pairs calculation is then carried out via degeneration, localisation, vanishing results, and new multiple cover formulae.
A Comment on Quantum Distribution Functions and the OSV Conjecture
Gómez, C; Gomez, Cesar; Montanez, Sergio
2006-01-01
Using the attractor mechanism and the relation between the quantization of $H^{3}(M)$ and topological strings on a Calabi Yau threefold $M$ we define a map from BPS black holes into coherent states. This map allows us to represent the Bekenstein-Hawking-Wald entropy as a quantum distribution function on the phase space $H^{3}(M)$. This distribution function is a mixed Husimi/anti-Husimi distribution corresponding to the different normal ordering prescriptions for the string coupling and deviations of the complex structure moduli. From the integral representation of this distribution function in terms of the Wigner distribution we recover the Ooguri-Strominger-Vafa (OSV) conjecture in the region "at infinity" of the complex structure moduli space. The physical meaning of the OSV corrections are briefly discussed in this limit.
A comment on quantum distribution functions and the OSV conjecture
Energy Technology Data Exchange (ETDEWEB)
Gomez, Cesar [Instituto de Fisica Teorica CSIC/UAM, C-XVI Universidad Autonoma, E-28049 Madrid (Spain); Montanez, Sergio [Instituto de Fisica Teorica CSIC/UAM, C-XVI Universidad Autonoma, E-28049 Madrid (Spain)
2006-12-15
Using the attractor mechanism and the relation between the quantization of H{sup 3}(M) and topological strings on a Calabi Yau threefold M we define a map from BPS black holes into coherent states. This map allows us to represent the Bekenstein-Hawking-Wald entropy as a quantum distribution function on the phase space H{sup 3}(M). This distribution function is a mixed Husimi/anti-Husimi distribution corresponding to the different normal ordering prescriptions for the string coupling and deviations of the complex structure moduli. From the integral representation of this distribution function in terms of the Wigner distribution we recover the Ooguri-Strominger-Vafa (OSV) conjecture in the region 'at infinity' of the complex structure moduli space. The physical meaning of the OSV corrections are briefly discussed in this limit.
The mixed Littlewood conjecture for pseudo-absolute values
Harrap, Stephen
2010-01-01
In this paper we prove the mixed Littlewood conjecture for a p-adic absolute value and any pseudo-absolute value with bounded ratios. More precisely we show that if p is a prime and D is a pseudo-absolute value sequence with elements divisible by finitely many primes not equal to p, and if the terms of D grow more slowly than the exponential of a polynomial then the infimum over natural numbers n of the quantity n.|n|_p.|n|_D.||nx|| equals 0 for all real x. Our proof relies on two deep results, a measure rigidity theorem due to Lindenstrauss and lower bounds for linear forms in logarithms due to Baker and Wustholz. We also deduce the answer to the related metric question of how fast the infimum above tends to zero, for almost every x.
Investigation of the conjectured nucleon deformation at low momentum transfer
Sparveris, N F; Bernstein, A M; Bertozzi, W; Botto, T; Bourgeois, P; Calarco, J; Casagrande, F; Distler, M O; Dow, K; Farkondeh, M; Georgakopoulos, S V; Gilad, S; Hicks, R; Holtrop, M; Hotta, A; Jiang, X; Karabarbounis, A; Kirkpatrick, J; Kowalski, S; Milner, R; Miskimen, R; Nakagawa, I; Papanicolas, C N; Sarty, A J; Sato, Y; Sirca, S; Shaw, J; Six, E; Stave, S; Stiliaris, E; Tamae, T; Tsentalovich, G; Tschalär, C; Turchinetz, W E; Zhou, Z L; Zwart, T
2004-01-01
We report new precise H$(e,e^\\prime p)\\pi^0$ measurements at the $\\Delta(1232)$ resonance at $Q^2= 0.127$ (GeV/c)$^2$ using the MIT/Bates out-of-plane scattering (OOPS) facility. The data reported here are particularly sensitive to the transverse electric amplitude ($E2$) of the $\\gamma^* N\\to\\Delta$ transition. Analyzed together with previous data yield precise quadrupole to dipole amplitude ratios $EMR = (-2.3 \\pm 0.3_{stat+sys} \\pm 0.6_{model})%$ and $CMR = (-6.1 \\pm 0.2_{stat+sys}\\pm 0.5_{model})%$ and for $M^{3/2}_{1+} = (41.4 \\pm 0.3_{stat+sys}\\pm 0.4_{model})(10^{-3}/m_{\\pi^+})$. They give credence to the conjecture of deformation in hadronic systems favoring, at low $Q^2$, the dominance of mesonic effects.
Searching Exact Solutions for Compact Stars in Braneworld: a conjecture
Ovalle, J
2007-01-01
In the context of the braneworld, a spherically symmetric, static and nonhomogeneous stellar distribution with local and non-local bulk terms is studied. Using a toy solution, it is shown how the general relativistic limit could be lost while a solution is being generated on the brane. The source of this problem is clearly identified and solved by a general solution where a constraint can be identified. This constraint is physically interpreted as a necessary condition to regain general relativity, and a particular solution for it is used to find an exact analytical internal solution to no-uniform stellar distributions on the brane. It is shown that such an exact solution is possible due to the fact that bulk corrections to pressure, density and a metric component are a null source of anisotropic effects on the brane. A conjecture is proposed about the possibility of finding physically relevant exact solutions to non-uniform stellar distributions on the brane.
Notes on Ding-Iohara algebra and AGT conjecture
Awata, H; Hoshino, A; Kanai, M; Shiraishi, J; Yanagida, S
2011-01-01
We study the representation theory of the Ding-Iohara algebra $\\calU$ to find $q$-analogues of the Alday-Gaiotto-Tachikawa (AGT) relations. We introduce the endomorphism $T(u,v)$ of the Ding-Iohara algebra, having two parameters $u$ and $v$. We define the vertex operator $\\Phi(w)$ by specifying the permutation relations with the Ding-Iohara generators $x^\\pm(z)$ and $\\psi^\\pm(z)$ in terms of $T(u,v)$. For the level one representation, all the matrix elements of the vertex operators with respect to the Macdonald polynomials are factorized and written in terms of the Nekrasov factors for the $K$-theoretic partition functions as in the AGT relations. For higher levels $m=2,3,...$, we present some conjectures, which imply the existence of the $q$-analogues of the AGT relations.
Conjectures regarding kissing spheres hierarchy and quantum gravity unification
Energy Technology Data Exchange (ETDEWEB)
El Naschie, M.S. [Department of Astrophysics, University of Cairo (Egypt); Donghua University Shanghai (China)], E-mail: Chaossf@aol.com
2008-01-15
Conjectures regarding connections between hyper-spheres kissing problems in one- to eight-dimensional spaces and the inverse coupling constant of quantum gravity are presented. In particular we demonstrate that in S{sup (7)} and S{sup (8)} the coupling constants of the non-super-symmetric and the super-symmetric unification are given by {alpha}-bar{sub g}={sup 7}{radical}(K(128)){approx_equal}42 and {alpha}-bar{sub gs}={sup 8}{radical}(K(128)){approx_equal}26 respectively where K(128) {approx_equal} (2.18)(10){sup 11} is the sphere kissing number in D = 128 Euclidian space.
Global Units modulo Circular Units : descent without Iwasawa's Main Conjecture
Belliard, Jean-Robert
2009-01-01
Iwasawa's classical asymptotical formula relates the orders of the $p$-parts $X_n$ of the ideal class groups along a $\\ZM_p$-extension $F_\\infty/F$ of a number field $F$, to Iwasawa structural invariants $\\la$ and $\\mu$ attached to the inverse limit $X_\\infty=\\limpro X_n$. It relies on "good" descent properties satisfied by $X_n$. If $F$ is abelian and $F_\\infty$ is cyclotomic it is known that the $p$-parts of the orders of the global units modulo circular units $U_n/C_n$ are asymptotically equivalent to the $p$-parts of the ideal class numbers. This suggests that these quotients $U_n/C_n$, so to speak unit class groups, satisfy also good descent properties. We show this directly, i.e. without using Iwasawa's Main Conjecture.
Cognition and Language: From Apprehension to Judgment -- Quantum Conjectures
Arecchi, F. T.
2014-12-01
We critically discuss the two moments of human cognition, namely, apprehension (A), whereby a coherent perception emerges from the recruitment of neuronal groups, and judgment (B), that entails the comparison of two apprehensions acquired at different times, coded in a suitable language and recalled by memory. (B) requires selfconsciousness, in so far as the agent who expresses the judgment must be aware that the two apprehensions are submitted to his/her own scrutiny and that it is his/her duty to extract a mutual relation. Since (B) lasts around 3 seconds, the semantic value of the pieces under comparison must be decided within this time. This implies a fast search of the memory contents. As a fact, exploring human subjects with sequences of simple words, we find evidence of a limited time window, corresponding to the memory retrieval of a linguistic item in order to match it with the next one in a text flow (be it literary, or musical,or figurative). Classifying the information content of spike trains, an uncertainty relation emerges between the bit size of a word and its duration. This uncertainty is ruled by a constant that can be given a numerical value and that has nothing to do with Planck's constant. A "quantum conjecture" in the above sense might explain the onset and decay of the memory window connecting successive pieces of a linguistic text. The conjecture here formulated is applicable to other reported evidences of quantum effects in human cognitive processes, so far lacking a plausible framework since no efforts to assign a quantum constant have been associated.
Hilbert-P\\'olya Conjecture, Zeta-Functions and Bosonic Quantum Field Theories
Andrade, Julio
2013-01-01
The original Hilbert and P\\'olya conjecture is the assertion that the non-trivial zeros of the Riemann zeta function can be the spectrum of a self-adjoint operator. So far no such operator was found. However the suggestion of Hilbert and P\\'olya, in the context of spectral theory, can be extended to approach other problems and so it is natural to ask if there is a quantum mechanical system related to other sequences of numbers which are originated and motivated by Number Theory. In this paper we show that the functional integrals associated with a hypothetical class of physical systems described by self-adjoint operators associated with bosonic fields whose spectra is given by three different sequence of numbers cannot be constructed. The common feature of the sequence of numbers considered here, which causes the impossibility of zeta regularization, is that the various Dirichlet series attached to such sequences - such as those which are sums over "primes" of $(\\mathrm{norm} \\ P)^{-s}$ have a natural boundar...
关于Steiner比猜想%A Report on the Steiner Ratio Conjecture
Institute of Scientific and Technical Information of China (English)
越民义
2000-01-01
The paper consists of an introduction and two sections. In the introduction we give a short historical review about this problem and, incidentally, point out some mistakes in the paper by Du and Hwang [4], and assert that their proof is wrong. By this way, we hope to be able to justify our motive of writing this paper. Section 2 gives some new and simple proofs for the cases n =3, 4 and 5. In section 3, the general case is discussed in details, and a proof is given to the truth of the Steiner Ratio Conjecture.%本文所讨论的是Steiner比猜想.全文共分两部分:第一部分包括历史回顾和对n=3,4,5三种情况对该猜想的正确性给出了简单的证明;第二部分则对于一般的n给出了一个证明.
Directory of Open Access Journals (Sweden)
Lisa Mwaikambo
2016-03-01
Full Text Available Access to training opportunities is strongly correlated with health workers’ motivation because it enables health workers to take on more challenging duties. Mobile technology can be leveraged for professional development support by providing access to open education resources. Community Health Nurses (CHNs in Ghana are the frontline health workers of the Ghana Health Service (GHS and play a vital role in extending maternal and child health care to rural communities. However, as the lowest credentialed nurses, they are at the bottom of the GHS hierarchy. CHNs have limited opportunities for career advancement and report challenges with isolation and lack of resources. Leveraging open-source technology platforms and open eLearning content, the Care Community Hub (CCH project sought to address these barriers in CHN motivation by developing and deploying a mobile application (app, CHN on the Go, to CHNs in five rural districts. The app supports CHNs through tools for continuous learning, diagnostic decision-making, and improved nurse-supervisor interactions. This paper focuses on the adaptation and use of the open eLearning content to address CHNs’ motivation challenges and, ultimately, improve their knowledge and job performance as a result of having access to open education resources.
Directory of Open Access Journals (Sweden)
Donna Sundre
2012-01-01
Full Text Available This study from the Norwegian University of Science and Technology (NTNU examines students’ learning goals and attitudes toward mathematics in a first-year calculus course in undergraduate engineering education. Achievement motivation research using the Achievement Goal Questionnaire (AGQ is advanced from current literature with two additions: (1 a course specific context using introductory college calculus students, and (2 participation of Norwegian students.Pre- and posttest measures of attitudes indicate that students do change learning goals over time, unfortunately opposite to the instructors’ aspirations. A significant increase in “Mastery Avoidance” and “Work Avoidance” was accompanied with a drop in “Mastery Approach” and “Performance Approach”. Variables such as value, motivation and enjoyment decreased along with a significant drop in self-confidence.
Institute of Scientific and Technical Information of China (English)
于雪霞; 石春生; 李靖
2012-01-01
National defence science and technology award was an important system in the field of national defence technology innovation. And it brought positive motivation to national defence technology innovation. By reviewing its origin and analyzing its essence, the paper put forward the motivation frame of national defence science and technology award on technology innovation, and then analyzed the motivation mechanism. It pointed out that national defence science and technology award played an important role in advancing the national defence technology innovation through inspiring power, stabilizing team, introducing competition and cultivating body.%国防科技奖励是国防技术创新领域中的重要制度形式,它的建立对国防技术创新活动产生了积极的激励作用.回顾国防科技奖励的起源,分析其本质,提出国防科技奖励对国防技术创新的激励作用框架,深入剖析其激励作用机理,指出正是通过不断地激发国防技术创新动力、稳定国防技术创新团队、引入国防技术创新竞争和培育国防技术创新主体等方式,国防科技奖励制度发挥了促进国防技术创新又好又快地发展的作用.
On the Beilinson-Hodge conjecture for $H^2$ and rational varieties
Chatzistamatiou, Andre
2011-01-01
The Beilinson-Hodge conjecture asserts the surjectivity of the cycle map $$H^n_M(X,\\Q(n)) \\to {\\rm Hom}_{MHS}(\\Q(-n),H^n(X,\\Q))$$ for all positive integers $n$ and every smooth complex algebraic variety $X$. For $n=2$, we prove the conjecture if $X$ is rational.
The bounded isometry conjecture for the Kodaira-Thurston manifold and 4-Torus
Han, Zhigang
2007-01-01
The purpose of this note is to study the bounded isometry conjecture proposed by Lalonde and Polterovich. In particular, we show that the conjecture holds for the Kodaira-Thurston manifold with the standard symplectic form and for the 4-torus with all linear symplectic forms.
Modelling of and Conjecturing on a Soccer Ball in a Korean Eighth Grade Mathematics Classroom
Lee, Kyeong-Hwa
2011-01-01
The purpose of this article was to describe the task design and implementation of cultural artefacts in a mathematics lesson based on the integration of modelling and conjecturing perspectives. The conceived process of integrating a soccer ball into mathematics lessons via modelling- and conjecturing-based instruction was first detailed. Next, the…
Proof of an entropy conjecture for Bloch coherent spin states and its generalizations
DEFF Research Database (Denmark)
H. Lieb, Elliott; Solovej, Jan Philip
2014-01-01
in 1978 who also extended the conjecture to Bloch SU(2) spin-coherent states for every angular momentum $J$. This conjecture is proved here. We also recall our 1991 extension of the Wehrl map to a quantum channel from $J$ to $K=J+1/2, J+1, ...$, with $K=\\infty$ corresponding to the Wehrl map to classical...
A Proof of George Andrews' and David Robbins' $q$-TSPP Conjecture
Koutschan, Christoph; Zeilberger, Doron
2010-01-01
The conjecture that the orbit-counting generating function for totally symmetric plane partitions can be written as an explicit product-formula, has been stated independently by George Andrews and David Robbins around 1983. We present a proof of this long-standing conjecture.
Notes from the Underground: A Propos of Givental's Conjecture
Energy Technology Data Exchange (ETDEWEB)
Song, Yun S.
2001-04-11
These brief notes record our puzzles and findings surrounding Givental's recent conjecture which expresses higher genus Gromov-Witten invariants in terms of the genus-0 data. We limit our considerations to the case of a projective line, whose Gromov-Witten invariants are well-known and easy to compute. We make some simple checks supporting his conjecture.
Verification of the Firoozbakht conjecture for primes up to four quintillion
Kourbatov, Alexei
2015-01-01
If $p_k$ is the k-th prime, the Firoozbakht conjecture states that the sequence $(p_k)^{1/k}$ is strictly decreasing. We use the table of first-occurrence prime gaps in combination with known bounds for the prime-counting function to verify the Firoozbakht conjecture for primes up to four quintillion $(4\\times10^{18})$.
The Erd(o)s-Sós Conjecture for Graphs Whose Complements Contain No C4
Institute of Scientific and Technical Information of China (English)
Jian-hua Yin; Jiong-sheng Li
2004-01-01
Erd(o)s and Sós conjectured in 1963 (see [1], Problem 12 in 247) that every graph G on n vertices with size e(G) > 12 n(k - 1) contains every tree T of size k. In this paper, we prove the conjecture for graphs whose complements contain no cycles of length 4.
Constraining the interacting dark energy models from weak gravity conjecture and recent observations
Chen, Ximing; Pan, Nana; Gong, Yungui
2010-01-01
We examine the effectiveness of the weak gravity conjecture in constraining the dark energy by comparing with observations. For general dark energy models with plausible phenomenological interactions between dark sectors, we find that although the weak gravity conjecture can constrain the dark energy, the constraint is looser than that from the observations.
Limits from Weak Gravity Conjecture on Chaplygin-Gas-Type Models
Institute of Scientific and Technical Information of China (English)
WU Xing; ZHU Zong-Hong
2008-01-01
@@ The weak gravity conjecture is proposed as a criterion to distinguish the landscape from the swampland in string theory. As an application in cosmology of this conjecture, we use it to impose theoretical constraint on parameters of the Chaplygin-gas-type models. Our analysis indicates that the Chaplygin-gas-type models realized in quintessence field are in the swampland.
A NEGATIVE ANSWER TO A CONJECTURE ON SELF-SIMILAR SETS WITH OPEN SET CONDITION
Institute of Scientific and Technical Information of China (English)
Jiandong Yin
2009-01-01
Zhou and Feng posed a conjecture on self-similar set in 2004. In this paper, a self-similar set is constructed which has a best covering but its natural covering is not a best one. Thus, we indeed give a negative answer to the conjecture.
Noncommutative Versions of the Singer-Wermer Conjecture with Linear Left θ-derivations
Institute of Scientific and Technical Information of China (English)
Yong Soo JUNG; Kyoo Hong PARK
2008-01-01
The noncommutative Singer-Wermer conjecture states that every linear(possibly unbounded)derivation on a(possibly noncommutative)Banach algebra maps into its Jacobson radical.This conjecture is still an open question for more than thirty years.In this paper we approach this question via linear left θ-derivations.
Modelling of and Conjecturing on a Soccer Ball in a Korean Eighth Grade Mathematics Classroom
Lee, Kyeong-Hwa
2011-01-01
The purpose of this article was to describe the task design and implementation of cultural artefacts in a mathematics lesson based on the integration of modelling and conjecturing perspectives. The conceived process of integrating a soccer ball into mathematics lessons via modelling- and conjecturing-based instruction was first detailed. Next, the…
Test Driven Development: Advancing Knowledge by Conjecture and Confirmation
Directory of Open Access Journals (Sweden)
Manfred Lange
2011-12-01
Full Text Available Test Driven Development (TDD is a critical agile software development practice that supports innovation in short development cycles. However, TDD is one of the most challenging agile practices to adopt because it requires changes to work practices and skill sets. It is therefore important to gain an understanding of TDD through the experiences of those who have successfully adopted this practice. We collaborated with an agile team to provide this experience report on their adoption of TDD, using observations and interviews within the product development environment. This article highlights a number of practices that underlie successful development with TDD. To provide a theoretical perspective that can help to explain how TDD supports a positive philosophy of software development, we have revised Northover et al.’s conceptual framework, which is based on a four stage model of agile development, to reinterpret Popper’s theory of conjecture and falsification in the context of agile testing strategies. As a result of our findings, we propose an analytical model for TDD in agile software development which provides a theoretical basis for further investigations into the role of TDD and related practices.
Searching Exact Solutions for Compact Stars in Braneworld:. a Conjecture
Ovalle, J.
In the context of the braneworld, a method to find consistent solutions to Einstein's field equations in the interior of a spherically symmetric, static and non-uniform stellar distribution with Weyl stresses is developed. This method, based on the fact that any braneworld stellar solution must have the general relativity solution as a limit, produces a constraint which reduces the degrees of freedom on the brane. Hence the nonlocality and non-closure of the braneworld equations can be overcome. The constraint found is physically interpreted as a necessary condition to regain general relativity, and a particular solution for it is used to find an exact and physically acceptable analytical internal solution to no-uniform stellar distributions on the brane. It is shown that such an exact solution is possible due to the fact that bulk corrections to pressure, density and a metric component are a null source of anisotropic effects on the brane. A conjecture is proposed regarding the possibility of finding physically relevant exact solutions to non-uniform stellar distributions on the brane.
2015-01-01
This book presents a broad design purview within the framework of “pre-design, design, and post-design” by focusing on the “motive of design,” which implies an underlying reason for the design of a product. The chapters are comprised of papers based on discussions at the “Design Research Leading Workshop” held in Nara, Japan, in 2013. This book encourages readers to enhance and expand their thinking within a widened design perspective.
An additive combinatorics approach to the log-rank conjecture in communication complexity
Ben-Sasson, Eli; Zewi, Noga
2011-01-01
For a $\\{0,1\\}$-valued matrix $M$ let $\\rm{CC}(M)$ denote the deterministic communication complexity of the boolean function associated with $M$. The log-rank conjecture of Lov\\'{a}sz and Saks [FOCS 1988] states that $\\rm{CC}(M) \\leq \\log^c(\\rm{rank}(M))$ for some absolute constant $c$ where $\\rm{rank}(M)$ denotes the rank of $M$ over the field of real numbers. We show that $\\rm{CC}(M)\\leq c \\cdot \\rm{rank}(M)/\\log \\rm{rank}(M)$ for some absolute constant $c$, assuming a well-known conjecture from additive combinatorics known as the Polynomial Freiman-Ruzsa (PFR) conjecture. Our proof is based on the study of the "approximate duality conjecture" which was recently suggested by Ben-Sasson and Zewi [STOC 2011] and studied there in connection to the PFR conjecture. First we improve the bounds on approximate duality assuming the PFR conjecture. Then we use the approximate duality conjecture (with improved bounds) to get the aforementioned upper bound on the communication complexity of low-rank martices, where thi...
Analytical study of the conjecture rule for the combination of multipole effects in LHC
Guignard, Gilbert
1997-01-01
This paper summarizes the analytical investigation done on the conjecture law found by tracking for the effect on the dynamic aperture of the combination of two multipoles of various order. A one-dimensional model leading to an integrable system has been used to find closed formulae for the dynamic aperture associated with a fully distributed multipole. The combination has then been studied and the resulting expression compared with the assumed conjecture law. For integrated multipoles small with respect to the focusing strength, the conjecture appears to hold, though with an exponent different from the one expected by crude reasoning.
Weak Gravity Conjecture and Holographic Dark Energy Model with Interaction and Spatial Curvature
Institute of Scientific and Technical Information of China (English)
SUN Cheng-Yi
2011-01-01
In the paper, we apply the weak gravity conjecture to the holographic quintessence model of dark energy.Three different holographic dark energy models are considered: without the interaction in the non-flat universe; with interaction in the flat universe; with interaction in the non-flat universe. We find that only in the models with the spatial curvature and interaction term proportional to the energy density of matter, it is possible for the weak gravity conjecture to be satisfied. And it seems that the weak gravity conjecture favors an open universe and the decaying of matter into dark energy.
The Shapiro Conjecture Prompt or Delayed Collapse in the head-on collision of neutron stars?
Miller, M; Tobias, M; Miller, Mark; Suen, Wai-Mo; Tobias, Malcolm
1999-01-01
We study the question of prompt vs. delayed collapse in the head-on collision of two neutron stars. We show that the prompt formation of a black hole is possible, contrary to a conjecture of Shapiro which claims that collapse is delayed until after neutrino cooling. We discuss the insight provided by Shapiro's conjecture and its limitation. An understanding of the limitation of the conjecture is provided in terms of the many time scales involved in the problem. General relativistic simulations in the Einstein theory with the full set of Einstein equations coupled to the general relativistic hydrodynamic equations are carried out in our study.
On the non-commutative Local Main Conjecture for elliptic curves with complex multiplication
Venjakob, Otmar
2012-01-01
This paper is a natural continuation of the joint work [6] on non-commutative Main Conjectures for CM elliptic curves: now we concentrate on the local Main Conjecture or more precisely on the epsilon-isomorphism conjecture by Fukaya and Kato in [20]. Our results rely heavily on Kato's unpublished proof of (commutative) epsilon-isomorphisms for one dimensional representations of G_{Q_p} in [24]. For the convenience of the reader we give a slight modification or rather reformulation of it in the language of [20] and extend it to the (slightly non-commutative) semi-global setting.
Culmer, Nathan Paul
2012-01-01
Change is an organizational inevitability. There are few fields that undergo change more rapidly than information technology. Keeping up with the pace of change in a field so inclined toward change may take a unique toll on workers in information technology. Yet, little has been done to investigate workers' orientations towards change in this…
Stevenson, Heidi J.
2014-01-01
The Business Roundtable (2013) website presents a common narrative in regard to STEM (Science, Technology, Engineering and Mathematics) education, "American students are falling behind in math and science. Fewer and fewer students are pursuing careers in science, technology, engineering and mathematics, and American students are performing at…
Culmer, Nathan Paul
2012-01-01
Change is an organizational inevitability. There are few fields that undergo change more rapidly than information technology. Keeping up with the pace of change in a field so inclined toward change may take a unique toll on workers in information technology. Yet, little has been done to investigate workers' orientations towards change in this…
Proof of a Null Penrose Conjecture using a new Quasi-local Mass
Roesch, Henri
2016-01-01
We define an explicit quasi-local mass functional which is non-decreasing along all foliations (satisfying a convexity assumption) of null cones. We use this new functional to prove the null Penrose conjecture under fairly generic conditions.
A counterexample to Beck's conjecture on the discrepancy of three permutations
Newman, Alantha
2011-01-01
Given three permutations on the integers 1 through n, consider the set system consisting of each interval in each of the three permutations. Jozsef Beck conjectured (c. 1987) that the discrepancy of this set system is O(1). We give a counterexample to this conjecture: for any positive integer n = 3^k, we exhibit three permutations whose corresponding set system has discrepancy Omega(log(n)). Our counterexample is based on a simple recursive construction, and our proof of the discrepancy lower bound is by induction. This example also disproves a generalization of Beck's conjecture due to Spencer, Srinivasan and Tetali, who conjectured that a set system corresponding to l permutations has discrepancy O(sqrt(l)).
Brief Comments on "The Shapiro Conjecture, Prompt or Delayed Collapse ?" by Miller, Suen and Tobias
Shapiro, S L
1999-01-01
Recent numerical simulations address a conjecture by Shapiro that when two neutron stars collide head-on from rest at infinity, sufficient thermal pressure may be generated to support the hot remnant in quasi-static equilibrium against collapse prior to neutrino cooling. The conjecture is meant to apply even when the total remnant mass exceeds the maximum mass of a cold neutron star. One set of simulations seems to corroborate the conjecture, while another, involving higher mass progenitors each very close to the maximum mass, does not. In both cases the total mass of the remnant exceeds the maximum mass. We point out numerical subtleties in performing such simulations when the progenitors are near the maximum mass; they can explain why the simulations might have difficulty assessing the conjecture in such high-mass cases.
Conjectures on the normal covering number of finite symmetric and alternating groups
Directory of Open Access Journals (Sweden)
Daniela Bubboloni
2014-06-01
Full Text Available Let gamma(Sn be the minimum number of proper subgroups Hi, i = 1,...,ell, of the symmetric group Sn such that each element in Sn lies in some conjugate of one of the Hi. In this paper we conjecture that gamma(Sn =(n/2(1-1/p_1 (1-1/p_2 + 2, where p1, p2 are the two smallest primes in the factorization of n and n is neither a prime power nor a product of two primes. Support for the conjecture is given by a previous result for the case where n has at most two distinct prime divisors. We give further evidence by confirming the conjecture for certain integers of the form n = 15q, for an infinite set of primes q, and by reporting on a Magma computation. We make a similar conjecture for gamma(An, when n is even, and provide a similar amount of evidence.
Tiny graviton matrix theory: DLCQ of IIB plane-wave string theory, a conjecture
Energy Technology Data Exchange (ETDEWEB)
Sheikh-Jabbari, Mohammad M. [Department of Physics, Stanford University, 382 via Pueblo Mall, Stanford CA 94305-4060 (United States)]. E-mail: jabbari@itp.stanford.edu
2004-09-01
We conjecture that the discrete light-cone quantization (DLCQ) of strings on the maximally supersymmetric type IIB plane-wave background in the sector with J units of light-cone momentum is a supersymmetric 0+1 dimensional U(J) gauge theory (quantum mechanics) with PSU(2|2) x PSU(2|2) x U(1) superalgebra. The conjectured hamiltonian for the plane-wave matrix (string) theory, the tiny graviton matrix theory, is the quantized (regularized) three brane action on the same background. We present some pieces of evidence for this conjecture through analysis of the hamiltonian , its vacua, spectrum and coupling constant. Moreover, we discuss an extension of our conjecture to the DLCQ of type IIB strings on AdS{sub 5} x S{sup 5} geometry. (author)
The generalized Hodge and Bloch conjectures are equivalent for general complete intersections
Voisin, Claire
2011-01-01
Let $X$ be a smooth complex projective variety with trivial Chow groups. (By trivial, we mean that the cycle class is injective.) We show (assuming the Lefschetz standard conjecture) that if the vanishing cohomology of a general complete intersection $Y$ of ample hypersurfaces in $X$ has geometric coniveau $\\geq c$, then the Chow groups of cycles of dimension $\\leq c-1$ of $Y$ are trivial. The generalized Bloch conjecture for $Y$ is this statement with "geometric coniveau" replaced by "Hodge coniveau".
Lang maps and Harris's conjecture a note in search for content
Abramovich, D
1995-01-01
The Lang map, namely the universal dominant rational map to a variety of general type, is constructed and briefly discussed in relation with arithmetic conjectures of Harris, Lang and Manin. Existence of the Lang map follows from the additivity of Kodaira dimension, but the fine structure depends on conjectures on birational classification of algebraic varieties. Serious applications of the Lang map are still being searched.
Comparison Theorems for Eigenvalues of Elliptic Operators and the Generalized Polya Conjecture
Energy Technology Data Exchange (ETDEWEB)
Wang Qiaoling, E-mail: wang@impa.br; Xia, Changyu, E-mail: xia@mat.unb.b [UnB, Departamento de Matematica (Brazil)
2010-09-15
We establish comparison theorems for eigenvalues between higher order elliptic equations on compact manifolds with boundary. As an application, it follows that if the Polya conjecture is true then so is the generalized Polya conjecture proposed by Ku et al. (J Differ Equ 97:127-139, 1992). We also obtain new lower bound for the eigenvalues of higher order elliptic equations on bounded domains in a Euclidean space.
Matrix Models and A Proof of the Open Analog of Witten's Conjecture
Buryak, Alexandr; Tessler, Ran J.
2017-08-01
In a recent work, R. Pandharipande, J. P. Solomon and the second author have initiated a study of the intersection theory on the moduli space of Riemann surfaces with boundary. They conjectured that the generating series of the intersection numbers satisfies the open KdV equations. In this paper we prove this conjecture. Our proof goes through a matrix model and is based on a Kontsevich type combinatorial formula for the intersection numbers that was found by the second author.
Cohomologie non ramifi\\'ee et conjecture de Hodge enti\\`ere
Colliot-Thélène, Jean-Louis
2010-01-01
Building upon the Bloch-Kato conjecture in Milnor K-theory, we relate the third unramified cohomology group with Q/Z coefficients with a group which measures the failure of the integral Hodge conjecture in degree 4. As a first consequence, a geometric theorem of the second-named author implies that the third unramified cohomology group with Q/Z coefficients vanishes on all uniruled threefolds. As a second consequence, a 1989 example by Ojanguren and the first named author implies that the integral Hodge conjecture in degree 4 fails for unirational varieties of dimension at least 6. For certain classes of threefolds fibered over a curve, we establish a relation between the integral Hodge conjecture and the computation of the index of the generic fibre. --------- En nous appuyant sur la conjecture de Bloch-Kato en K-th\\'eorie de Milnor, nous \\'etablissons un lien g\\'en\\'eral entre le d\\'efaut de la conjecture de Hodge enti\\`ere pour la cohomologie de degr\\'e 4 et le troisi\\`eme groupe de cohomologie non ramifi\\...
Patterson, Richard; Operskalski, Joachim T.; Barbey, Aron K.
2015-01-01
Although motivation is a well-established field of study in its own right, and has been fruitfully studied in connection with attribution theory and belief formation under the heading of “motivated thinking,” its powerful and pervasive influence on specifically explanatory processes is less well explored. Where one has a strong motivation to understand some event correctly, one is thereby motivated to adhere as best one can to normative or “epistemic” criteria for correct or accurate explanation, even if one does not consciously formulate or apply such criteria. By contrast, many of our motivations to explain introduce bias into the processes involved in generating, evaluating, or giving explanations. Non-epistemic explanatory motivations, or following Kunda's usage, “directional” motivations, include self-justification, resolution of cognitive dissonance, deliberate deception, teaching, and many more. Some of these motivations lead to the relaxation or violation of epistemic norms; others enhance epistemic motivation, so that one engages in more careful and thorough generational and evaluative processes. We propose that “real life” explanatory processes are often constrained by multiple goals, epistemic and directional, where these goals may mutually reinforce one another or may conflict, and where our explanations emerge as a matter of weighing and satisfying those goals. We review emerging evidence from psychology and neuroscience to support this framework and to elucidate the central role of motivation in human thought and explanation. PMID:26528166
Evolution of the mirror approach to fusion: some conjectures
Energy Technology Data Exchange (ETDEWEB)
Post, R.E.
1984-09-18
Some possible directions for the future evolution of the mirror approach to fusion are outlined, in the context of economically-motivated criteria. Speculations are given as to the potential advantages, economic and otherwise, of the use of axially-symmetric systems, operated in semi-collisional regimes of lower Q (fusion power balance ratio) than that projected for present-day tandem mirror designs. These regims include barely tandem modes, and ion-heated modes, in association with higher efficiency direct conversion. Another possible economically advantageous approach mentioned is the use of a tandem mirror plasma to stabilize a FRM (field-reversed mirror) plasma, with potential synergistic advantages.
Motivation and library management
Directory of Open Access Journals (Sweden)
Tatjana Likar
2000-01-01
Full Text Available The present article deals with motivation, its relation to management and its role and use in librarianship in our country and abroad. The countries where librarianship is well developed started to deal with library management and questions of motivation of library workers decades ago, whereas elsewhere the subject is at its start. The prerequisite for modern policy making is attention to the elements of modern library management. Librarians, library managers and directors of libraries should create a work environment providing long term satisfaction with work by means of certain knowledge and tools. The level of motivation of the staff is influenced by the so called higher factors deriving from the work process itself and related to work contents: achieve¬ment, recognition, trust and work itself. Extrinsic factors (income, interpersonal relations, technology of administration, company policy, working conditions, work con¬trol, personal security, job security and position... should exercise lesser impact on the level of motivation.
Directory of Open Access Journals (Sweden)
Richard ePatterson
2015-10-01
Full Text Available Although motivation is a well-established field of study in its own right, and has been fruitfully studied in connection with attribution theory and belief formation under the heading of motivated thinking, its powerful and pervasive influence on explanatory processes is less well explored. Where one has a strong motivation to understand some event correctly, one is thereby motivated to adhere as best one can to normative or epistemic criteria for correct or accurate explanation, even if one does not consciously formulate or apply such criteria. By contrast, many of our motivations to explain introduce bias into the processes involved in generating, evaluating, or giving of explanations. Non-epistemic explanatory motivations, or (following Kunda’s usage, directional motivations, include self-justification, resolution of cognitive dissonance, deliberate deception, teaching, and many more. Some of these motivations lead to the relaxation or violation of epistemic norms, combined with an effort to preserve the appearance of accuracy; others enhance epistemic motivation, so that one engages in more careful and thorough generational and evaluative processes. In short, real life explanatory processes are often constrained by multiple goals, epistemic and directional, where these goals may mutually reinforce one another or may conflict, and where our explanations emerge as a matter of weighing and satisfying those goals. Our proposals are largely programmatic, although we do review a good deal of relevant behavioral and neurological evidence. Specifically, we recognize five generative processes, some of which cover further sub-processes, and six evaluative processes. All of these are potential points of entry for the influence of motivation. We then suggest in some detail how specific sorts of explanatory motivation interact with specific explanatory processes.
Nolen, Susan Bobbitt; Horn, Ilana Seidel; Ward, Christopher J.
2015-01-01
This article describes a situative approach to studying motivation to learn in social contexts. We begin by contrasting this perspective to more prevalent psychological approaches to the study of motivation, describing epistemological and methodological differences that have constrained conversation between theoretical groups. We elaborate on…
DEFF Research Database (Denmark)
Karlsen, Kamilla; Humaidan, Peter; Sørensen, Lise H;
2013-01-01
This is a retrospective study to investigate whether motivational interviewing increases weight loss among obese or overweight women prior to fertility treatment. Women with body mass index (BMI) > 30 kg/m(2) approaching the Fertility Clinic, Regional Hospital Skive, were given advice about diet...... and physical activity with the purpose of weight loss. In addition, they were asked if they wanted to receive motivational interviewing. Among other data, age, height and weight were obtained. Main outcomes were weight loss measured in kg and decrease in BMI. We studied 187 women: 110 received sessions...... of motivational interviewing (intervention group, n = 110), 64 received motivational support by phone or e-mail only and 13 women did not wish any motivational support (control group, n = 77). The mean weight loss and decrease in BMI was greater in the intervention group compared with the control group (9.3 kg...
Kenan-Smalls, Yottie Marie
2011-01-01
The purpose of this quantitative study was to investigate diversity and inclusion from an age perspective among information technology (IT) professionals that were categorized as 4 different generations in the workforce today: Traditionalists, Baby Boomers, Generation X, and Generation Y. At the same time, this study sought to examine motivational…
Kenan-Smalls, Yottie Marie
2011-01-01
The purpose of this quantitative study was to investigate diversity and inclusion from an age perspective among information technology (IT) professionals that were categorized as 4 different generations in the workforce today: Traditionalists, Baby Boomers, Generation X, and Generation Y. At the same time, this study sought to examine motivational…
DEFF Research Database (Denmark)
Markussen, Thomas
2008-01-01
By applying Gilles Fauconnier & Mark Turner’s theory of conceptual blending to a design case I demonstrate how experiencing emotional qualities in technology design may influence the way users cognitively reconstruct standard expectations of use. In so doing, I expand the dominating cognitive...... theory of emotion in design in three central respects: (i) the understanding of mixed emotions is deepened; (ii) a more detailed explanation is given of the specific operations involved in appraisal processes grounded in embodied interaction; (iii) a structural model is proposed for mapping...
The Bourgain-Tzafriri conjecture and concrete constructions of non-pavable projections
Casazza, Peter G; Mixon, Dustin G; Tremain, Janet C
2010-01-01
It is known that the Kadison-Singer Problem (KS) and the Paving Conjecture (PC) are equivalent to the Bourgain-Tzafriri Conjecture (BT). Also, it is known that (PC) fails for $2$-paving projections with constant diagonal $1/2$. But the proofs of this fact are existence proofs. We will use variations of the discrete Fourier Transform matrices to construct concrete examples of these projections and projections with constant diagonal $1/r$ which are not $r$-pavable in a very strong sense. In 1989, Bourgain and Tzafriri showed that the class of zero diagonal matrices with small entries (on the order of $\\le 1/log^{1+\\epsilon}n$, for an $n$-dimensional Hilbert space) are {\\em pavable}. It has always been assumed that this result also holds for the BT-Conjecture - although no one formally checked it. We will show that this is not the case. We will show that if the BT-Conjecture is true for vectors with small coefficients (on the order of $\\le C/\\sqrt{n}$) then the BT-Conjecture is true and hence KS and PC are true.
Lee, Ahlam
2011-12-01
Using the Educational Longitudinal Study of 2002/06, this study examined the effects of the selected mathematical learning and teacher motivation factors on graduates' science, technology, engineering, and math (STEM) related major choices in 4-year colleges and universities, as mediated by math performance and math self-efficacy. Using multilevel structural equation modeling, I analyzed: (1) the association between mathematical learning instruction factors (i.e., computer, individual, and lecture-based learning activities in mathematics) and students' STEM major choices in 4-year colleges and universities as mediated by math performance and math self-efficacy and (2) the association between school factor, teacher motivation and students' STEM major choices in 4-year colleges and universities via mediators of math performance and math self-efficacy. The results revealed that among the selected learning experience factors, computer-based learning activities in math classrooms yielded the most positive effects on math self-efficacy, which significantly predicted the increase in the proportion of students' STEM major choice as mediated by math self-efficacy. Further, when controlling for base-year math Item Response Theory (IRT) scores, a positive relationship between individual-based learning activities in math classrooms and the first follow-up math IRT scores emerged, which related to the high proportion of students' STEM major choices. The results also indicated that individual and lecture-based learning activities in math yielded positive effects on math self-efficacy, which related to STEM major choice. Concerning between-school levels, teacher motivation yielded positive effects on the first follow up math IRT score, when controlling for base year IRT score. The results from this study inform educators, parents, and policy makers on how mathematics instruction can improve student math performance and encourage more students to prepare for STEM careers. Students
On the Erdős-Gyárfás Conjecture in Claw-Free Graphs
Directory of Open Access Journals (Sweden)
Nowbandegani Pouria Salehi
2014-08-01
Full Text Available The Erdős-Gyárfás conjecture states that every graph with minimum degree at least three has a cycle whose length is a power of 2. Since this conjecture has proven to be far from reach, Hobbs asked if the Erdős-Gyárfás conjecture holds in claw-free graphs. In this paper, we obtain some results on this question, in particular for cubic claw-free graphs
The generalized Kac-Wakimoto conjecture and support varieties for the Lie superalgebra osp(m|2n)
Kujawa, Jonathan
2011-01-01
Atypicality is a fundamental combinatorial invariant for simple supermodules of a basic Lie superalgebra. Boe, Nakano, and the author gave a conjectural geometric interpretation of atypicality via support varieties. Inspired by low dimensional topology, Geer, Patureau-Mirand, and the author gave a generalization of the Kac-Wakimoto atypicality conjecture. We prove both of these conjectures for the Lie superalgebra osp(m|2n).
Conjectures and experiments concerning the moments of $L(1/2,\\chi_d)$
Alderson, Matthew W
2011-01-01
We report on some extensive computations and experiments concerning the moments of quadratic Dirichlet $L$-functions at the critical point. We computed the values of $L(1/2,\\chi_d)$ for $- 5\\times 10^{10} < d < 1.3 \\times 10^{10}$ in order to numerically test conjectures concerning the moments $\\sum_{|d|
Revisiting the Zassenhaus conjecture on torsion units for the integral group rings of small groups
Indian Academy of Sciences (India)
Allen Herman; Gurmail Singh
2015-05-01
In recent years several new restrictions on integral partial augmentations for torsion units of $\\mathbb{Z}G$ have been introduced, which have improved the effectiveness of the Luthar–Passi method for checking the Zassenhaus conjecture for specific groups . In this note, we report that the Luthar–Passi method with the new restrictions are sufficient to verify the Zassenhaus conjecture with a computer for all groups of order less than 96, except for one group of order 48 – the non-split covering group of 4, and one of order 72 of isomorphism type ( × ) × 8. To verify the Zassenhaus conjecture for this group we give a new construction of normalized torsion units of $\\mathbb{Q}G$ that are not conjugate to elements of $\\mathbb{Z}G$.
Disproving the Peres conjecture by showing Bell nonlocality from bound entanglement.
Vértesi, Tamás; Brunner, Nicolas
2014-11-05
Quantum entanglement has a central role in many areas of physics. To grasp the essence of this phenomenon, it is fundamental to understand how different manifestations of entanglement relate to each other. In 1999, Peres conjectured that Bell nonlocality is equivalent to distillability of entanglement. The intuition of Peres was that the non-classicality of an entangled state, as witnessed via Bell inequality violation, implies that pure entanglement can be distilled from this state, hence making it useful for quantum information protocols. Subsequently, the Peres conjecture was shown to hold true in several specific cases, and became a central open question in quantum information theory. Here we disprove the Peres conjecture by showing that an undistillable bipartite entangled state--a bound entangled state--can violate a Bell inequality. Hence Bell nonlocality implies neither entanglement distillability, nor non-positivity under partial transposition. This clarifies the relation between three fundamental aspects of entanglement.
Durand, Fabien
2011-01-01
Nivat's conjecture is about the link between the pure periodicity of a subset $M$ of $\\ZZ^2$, i.e., invariance under translation by a fixed vector, and some upper bound on the function counting the number of different rectangular blocks occurring in $M$. Attempts to solve this conjecture have been considered during the last fifteen years. Let $d\\ge 2$. A legitimate extension to a multidimensional setting of the notion of periodicity is to consider sets of $\\ZZ^d$ definable by a first order formula in the Presburger arithmetic $$. With this latter notion and using a powerful criterion due to Muchnik, we solve an analogue of Nivat's conjecture and characterize sets of $\\ZZ^d$ definable in $$ in terms of some functions counting recurrent blocks, that is, blocks occurring infinitely often.
Inequalities relating to Lp-version of Petty's conjectured projection inequality
Institute of Scientific and Technical Information of China (English)
WANG Wei-dong; LENG Gang-song
2007-01-01
Petty's conjectured projection inequality is a famous open problem in the theory of convex bodies. In this paper, it is shown that an inequality relating to Lp-version of the Petty's conjectured projection inequality is developed by using the notions of the Lp-mixed volume and the Lp-dual mixed volume, the relation of the Lp-projection body and the geometric body Γ-pK, the Bourgain-Milman inequality and the Lp-BusemannPetty inequality. In addition, for each origin-symmetric convex body, by applying the Jensen inequality and the monotonicity of the geometric body Γ-pK, the reverses of Lp-version of the Petty's conjectured projection inequality and the Lp-Petty projection inequality are given, respectively.
Wormholes, emergent gauge fields, and the weak gravity conjecture
Energy Technology Data Exchange (ETDEWEB)
Harlow, Daniel [Center for the Fundamental Laws of Nature, Physics Department, Harvard University,Cambridge MA, 02138 (United States)
2016-01-20
This paper revisits the question of reconstructing bulk gauge fields as boundary operators in AdS/CFT. In the presence of the wormhole dual to the thermofield double state of two CFTs, the existence of bulk gauge fields is in some tension with the microscopic tensor factorization of the Hilbert space. I explain how this tension can be resolved by splitting the gauge field into charged constituents, and I argue that this leads to a new argument for the “principle of completeness”, which states that the charge lattice of a gauge theory coupled to gravity must be fully populated. I also claim that it leads to a new motivation for (and a clarification of) the “weak gravity conjecture”, which I interpret as a strengthening of this principle. This setup gives a simple example of a situation where describing low-energy bulk physics in CFT language requires knowledge of high-energy bulk physics. This contradicts to some extent the notion of “effective conformal field theory”, but in fact is an expected feature of the resolution of the black hole information problem. An analogous factorization issue exists also for the gravitational field, and I comment on several of its implications for reconstructing black hole interiors and the emergence of spacetime more generally.
Donehew, G R
1979-01-01
Although pharmacists are developing interest in many types of pharmacy practice, they are still spending the bulk of their time in the prescription dispensing process. Any effort to provide motivation must consider the prescription dispensing process. The pharmacy literature includes only a few studies that dealt with pharmacists as people. The studies usually showed that pharmacists basically were unhappy with their jobs. In developing a motivational climate for pharmacists, pharmacy supervisors have several concepts to consider: the hierarchy of needs by Maslow; the expectancy theory by Hampton; the gygiene-motivator theory by Herzberg; and the Theory Y management approach by McGregor. Because pharmacists must be induced to enter and remain in an organization, supervisors should be aware of the need to use any technique available in developing a motivational climate.
DEFF Research Database (Denmark)
Grunert, Klaus G; Rosendahl, Jacob; Andronikidis, Andreas I.
2013-01-01
, and quenching one’s thirst. The non-alcoholic products scoring low on functionality are coffee, tea, soft drinks, and energy drinks. Analysis of socio-demographic differences resulted in only a few effects. Men, lower education groups, and lower income groups are more likely to drink alcohol for reasons other......This chapter presents an analysis of what consumer in Europe drink and why they drink what they drink. The concept of drinking motives is developed and defined, and analysis of data on drinking motives shows that these can be grouped into two major classes: self-expressive and functional....... This distinction is universal and henceapplies across Europe. However, the importance of self-expressive as compared to functional motives, as well as the way in which these relate to different beverages, does differ across Europe. Both dimensions are relevant for the motives for drinking non-alcoholic drinks...
RECOGNIZING MOTIVES: THE DISSENSUAL SELF
DEFF Research Database (Denmark)
Nissen, Morten; Christensen, Tine Friis
2017-01-01
, these technologies confirm a common-sense, managerial self; others read them as a ‘poetics of practice’ that performs and produces new motives and selves in a liminal space of discursive creativity. These two readings are superseded as we – with art theory from Vygotsky through Brecht to Groys, Bourriaud...... that reconfigures sense and meaning, can play a part. This chapter aims at suggesting these potentials by rearticulating activities in which people display (represent, avow, reflect, expose, externalize, etc.) their motives. Most contemporary ‘motivational technologies’ stage a pragmatic self-calculation. For some...... emerging selves, senses, and motives....
Reduction of the Hall-Paige conjecture to sporadic simple groups
Wilcox, Stewart
2010-01-01
A complete mapping of a group $G$ is a permutation $\\phi:G\\rightarrow G$ such that $g\\mapsto g\\phi(g)$ is also a permutation. Complete mappings of $G$ are equivalent to tranversals of the Cayley table of $G$, considered as a latin square. In 1953, Hall and Paige proved that a finite group admits a complete mapping only if its Sylow-2 subgroup is trivial or non-cyclic. They conjectured that this condition is also sufficient. We prove that it is sufficient to check the conjecture for the 26 sporadic simple groups and the Tits group.
Anisotropic Power-law Inflation: A counter example to the cosmic no-hair conjecture
Soda, Jiro
2014-01-01
It is widely believed that anisotropy in the expansion of the universe will decay exponentially fast during inflation. This is often referred to as the cosmic no-hair conjecture. However, we find a counter example to the cosmic no-hair conjecture in the context of supergravity. As a demonstration, we present an exact anisotropic power-law inflationary solution which is an attractor in the phase space. We emphasize that anisotropic inflation is quite generic in the presence of anisotropic sources which couple with an inflaton.
Woltjer-Taylor State Without Taylor's Conjecture - Plasma Relaxation at all Wavelengths
Energy Technology Data Exchange (ETDEWEB)
Qin, Hong; Liu, Wandong; Li, Hong; Squire, Jonathan
2012-10-10
In astrophysical and laboratory plasmas, it has been discovered that plasmas relax towards the well-known Woltjer-Taylor state specified by ∇ x B = αB for a constant α . To explain how such a relaxed state is reached, Taylor developed his famous relaxation theory based on the conjecture that the relaxation is dominated by short wavelength fluctuations. However, there is no conclusive experimental and numerical evidence to support Taylor's conjecture. A new theory is developed, which predicts that the system will evolve towards the Woltjer-Taylor state for an arbitrary fluctuation spectrum.
Does horizon entropy satisfy a quantum null energy conjecture?
Fu, Zicao; Marolf, Donald
2016-12-01
A modern version of the idea that the area of event horizons gives 4G times an entropy is the Hubeny-Rangamani causal holographic information (CHI) proposal for holographic field theories. Given a region R of a holographic QFTs, CHI computes A/4G on a certain cut of an event horizon in the gravitational dual. The result is naturally interpreted as a coarse-grained entropy for the QFT. CHI is known to be finitely greater than the fine-grained Hubeny-Rangamani-Takayanagi (HRT) entropy when \\partial R lies on a Killing horizon of the QFT spacetime, and in this context satisfies other non-trivial properties expected of an entropy. Here we present evidence that it also satisfies the quantum null energy condition (QNEC), which bounds the second derivative of the entropy of a quantum field theory on one side of a non-expanding null surface by the flux of stress-energy across the surface. In particular, we show CHI to satisfy the QNEC in 1 + 1 holographic CFTs when evaluated in states dual to conical defects in AdS3. This surprising result further supports the idea that CHI defines a useful notion of coarse-grained holographic entropy, and suggests unprecedented bounds on the rate at which bulk horizon generators emerge from a caustic. To supplement our motivation, we include an appendix deriving a corresponding coarse-grained generalized second law for 1 + 1 holographic CFTs perturbatively coupled to dilaton gravity.
Mixed motives and their realization in derived categories
Huber, Annette
1995-01-01
The conjectural theory of mixed motives would be a universal cohomology theory in arithmetic algebraic geometry. The monograph describes the approach to motives via their well-defined realizations. This includes a review of several known cohomology theories. A new absolute cohomology is introduced and studied. The book assumes knowledge of the standard cohomological techniques in algebraic geometry as well as K-theory. So the monograph is primarily intended for researchers. Advanced graduate students can use it as a guide to the literature.
Hamilton decompositions of regular expanders: a proof of Kelly's conjecture for large tournaments
Kühn, Daniela
2012-01-01
A long-standing conjecture of Kelly states that every regular tournament on n vertices can be decomposed into (n-1)/2 edge-disjoint Hamilton cycles. We prove this conjecture for large n. In fact, we prove a far more general result, based on our recent concept of robust expansion and a new method for decomposing graphs. We show that every sufficiently large regular digraph G on n vertices whose degree is linear in n and which is a robust outexpander has a decomposition into edge-disjoint Hamilton cycles. This enables us to obtain numerous further results, e.g. as a special case we confirm a conjecture of Erdos on packing Hamilton cycles in random tournaments. As corollaries to the main result, we also obtain several results on packing Hamilton cycles in undirected graphs, giving e.g. the best known result on a conjecture of Nash-Williams. We also apply our result to solve a problem on the domination ratio of the Asymmetric Travelling Salesman problem, which was raised e.g. by Glover and Punnen as well as Alon,...
The Hodge conjecture for self-products of certain K3 surfaces
Schlickewei, Ulrich
2009-01-01
We use a result of van Geemen to determine the endomorphism algebra of the Kuga--Satake variety of a K3 surface with real multiplication. This is applied to prove the Hodge conjecture for self-products of double covers of $\\PP^2$ which are ramified along six lines.
Directory of Open Access Journals (Sweden)
Linz Simone
2010-10-01
Full Text Available Abstract Background Recently, Hill et al. 1 implemented a new software package--called SPRIT--which aims at calculating the minimum number of horizontal gene transfer events that is needed to simultaneously explain the evolution of two rooted binary phylogenetic trees on the same set of taxa. To this end, SPRIT computes the closely related so-called rooted subtree prune and regraft distance between two phylogenies. However, calculating this distance is an NP-hard problem and exact algorithms are often only applicable to small- or medium-sized problem instances. Trying to overcome this problem, Hill et al. propose a divide-and-conquer approach to speed up their algorithm and conjecture that this approach can be used to compute the rooted subtree prune and regraft distance exactly. Results In this note, we present a counterexample to Hill et al's conjecture and subsequently show that a modified version of their conjecture holds. Conclusion While Hill et al's conjecture may result in an overestimate of the rooted subtree prune and regraft distance, a slightly more restricted version of their approach gives the desired outcome and can be applied to speed up the exact calculation of this distance between two phylogenies.
The proof of Ushio's conjecture concerning path factorization of complete bipartite graphs
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
Let Km,n be a complete bipartite graph with two partite sets having m and n vertices, respectively. A Pv-factorization of Km,n is a set of edge-disjoint Pv-factors of Km,n which partition the set of edges of Km,n. When v is an even number, Wang and Ushio gave a necessary and sufficient condition for existence of Pv-factorization of Km,n. When k is an odd number, Ushio in 1993 proposed a conjecture. Very recently, we have proved that Ushio's conjecture is true when v = 4k - 1. In this paper we shall show that Ushio Conjecture is true when v = 4k + 1, and then Ushio's conjecture is true. That is, we will prove that a necessary and sufficient condition for the existence of a P4k+1-factorization of Km,n is (i) 2km ≤ (2k + 1)n,(ii) 2kn ≤ (2k + 1)m, (iii) m + n ≡ 0 (mod 4k + 1), (iv) (4k + 1)mn/[4k(m + n)] is an integer.
The elementary theory of groups a guide through the proofs of the Tarski conjectures
Fine, Benjamin; Myasnikov, Alexei; Rosenberger, Gerhard; Spellman, Dennis
2014-01-01
After being an open question for sixty years the Tarski conjecture was answered in the affirmative by Olga Kharlampovich and Alexei Myasnikov and independently by Zlil Sela. This book is an examination of the material on the general elementary theory of groups that is necessary to begin to understand the proofs.
Morgan, Stephen L.; Todd, Jennifer J.
2009-01-01
This article reexamines the conjecture of James S. Coleman that intergenerational social closure promotes student achievement in high schools, analyzing the best national data on academic achievement and social networks: the 2002 and 2004 waves of the Education Longitudinal Study. The results show that within the Catholic school sector, schools…
Norton, Anderson
2008-01-01
This article reports on students' learning through conjecturing, by drawing on a semester-long teaching experiment with 6 sixth-grade students. It focuses on 1 of the students, Josh, who developed especially powerful ways of operating over the course of the teaching experiment. Through a fine-grained analysis of Josh's actions, this article…
Unfolding Mixed-Symmetry Fields in AdS and the BMV Conjecture I. General Formalism
Boulanger, Nicolas; Sundell, Per
2009-01-01
We present some generalities of unfolded on-shell dynamics that are useful in analyzing the BMV conjecture for mixed-symmetry fields in constantly curved backgrounds. In particular we discuss the unfolded notion of local degrees of freedom in theories with and without gravity and with and without massive deformation parameters, using the language of Weyl zero-form modules and their duals.
Canonical heights for plane polynomial maps of small topological degree: a conjecture of Silverman
Jonsson, Mattias
2012-01-01
We prove a conjecture of Silverman regarding canonical heights, in the case of plane polynomial mappings of small topological degree. The proof uses the existence, proved by Favre and the first author, of certain compactifications of the plane adapted to the dynamics.
Weak gravity conjecture as a razor criterium for exotic D-brane instantons
Addazi, Andrea
2017-01-01
We discuss implications of weak gravity conjecture (WGC) for exotic D-brane instantons. In particular, WGC leads to indirect stringent bounds on non-perturbative superpotentials generated by exotic instantons with many implications for phenomenology: R-parity violating processes, neutrino mass, μ-problem, neutron-antineutron transitions and collider physics.
On the Matsaev's conjecture for contractions on noncommutative Lp-spaces
Arhancet, Cédric
2010-01-01
We study the noncommutative analogue of the Matsaev's conjecture introduced by V.V. Peller, in 1985. We show that the conjecture is true for some classes of contractions on noncommutative $L_p$-spaces. In particular, we prove that the Schur multipliers associated with a real matrix on Schatten spaces $S_p$ and Fourier multipliers associated with a real function on $L_p\\big(\\VN(G)\\big)$, where $\\VN(G)$ is the von Neumann algebra of an amenable discrete group $G$, which are absolute contractions, satisfy the conjecture. For that, we construct isometric dilations for some Schur multipliers and Fourier multipliers, answering partially a question of V.V. Peller. Moreover, we disprove a conjecture of V. V. Peller. Indeed, if $S$ is the shift on $\\ell_p$ and $\\sigma$ the shift on the Schatten space $S_p$, the norms $\\bnorm{P(S)}_{\\ell_p \\xra{}\\ell_p}$ and $\\bnorm{P(\\sigma)\\ot \\Id_{S_p}}_{S_p(S_p) \\xra{}S_p(S_p)}$ are generally different for a complex polynomial $P$.
Fisher-Hartwig conjecture and the correlators in the inpenetrable Bose gas
Energy Technology Data Exchange (ETDEWEB)
Ovchinnikov, A.A. [Institute for Nuclear Research, RAS, Moscow 117312 (Russian Federation)], E-mail: ovch@ms2.inr.ac.ru
2009-01-12
We apply the theorems from the theory of Toeplitz determinants to calculate the asymptotics of various correlators including the exponential ones in the inpenetrable one-dimensional Bose gas system. The known correlators in the free-fermion system are also used to test the generalized Fisher-Hartwig conjecture.
Proof of the Wehrl-type Entropy Conjecture for Symmmetric SU(N) Coherent States
DEFF Research Database (Denmark)
Lieb, Elliott H.; Solovej, Jan Philip
2016-01-01
The Wehrl entropy conjecture for coherent (highest weight) states in representations of the Heisenberg group, which was proved in 1978 and recently extended by us to the group SU(2) SU(2) , is further extended here to symmetric representations of the groups SU(N) SU(N) for all N. This result gives...
Tax evasion in transition: Outcome of an institutional clash? - Testing Feige's conjecture
Gërxhani, K.
2003-01-01
A field survey of households was conducted in Tirana, Albania in 2000. A response rate of 89.3% yielded 1.340 valid questionnaires, allowing us to test Feige’s (1997) conjecture that more tax evasion will be observed, when formal and informal institutions clash. Respondents’ attitudes towards formal
Disproving Hibi's Conjecture with CoCoA or Projective Curves with bad Hilbert Functions
Niesi, G
1992-01-01
In this paper we show how to combine different techniques from Commutative Algebra and a systematic use of a Computer Algebra System (in our case mainly CoCoA) in order to explicitly construct Cohen-Macaulay domains, which are standard $k$-algebras and whose Hilbert function is ``bad". In particular we disprove a well-known conjecture by Hibi.
On AGT-W Conjecture and q-Deformed W-Algebra
Taki, Masato
2014-01-01
We propose an extension of the Alday-Gaiotto-Tachikawa-Wyllard conjecture to 5d SU(N) gauge theories. A Nekrasov partition function then coincides with the scalar product of the corresponding Gaiotto-Whittaker vectors of the q-deformed W_N algebra.
A conjecture on a class of elements of finite order in K2Fp
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
For a local field F the finite subgroups of K2F are expressed by a class of special elements of finite order, which makes a famous theorem built by Moore, Carroll, Tate and Merkurjev more explicit and also disproves a conjecture posed by Browkin.
Zumbo, Bruno D.; Pope, Gregory A.; Watson, Jackie E.; Hubley, Anita M.
1997-01-01
E. Roskam's (1985) conjecture that steeper item characteristic curve (ICC) "a" parameters (slopes) (and higher item total correlations in classical test theory) would be found with more concretely worded test items was tested with results from 925 young adults on the Eysenck Personality Questionnaire (H. Eysenck and S. Eysenck, 1975).…
The cosmic no-hair conjecture: A study of the Nariai solutions
Beyer, Florian
2010-01-01
In this talk, we investigate the cosmic no-hair conjecture for perturbed Nariai solutions within the class of Gowdy symmetric solutions of Einstein's field equations in vacuum with a positive cosmological constant. In particular, we are interested whether these perturbations allow to construct new cosmological black hole solutions.
Institute of Scientific and Technical Information of China (English)
杨优优; 范巍巍; 贾路路
2014-01-01
自编问卷对133名定向培养基层农技人员的入学动机进行调查，分析了入学动机对专业认可度、入学后表现情况等的影响，提出了通过加强诚信教育、激发学习动机等方式提高学习效果，达到培养目标。%This paper made a survey on the study motivation of 133 grassroots personnels of agricultural technology in the ori-ented training by self-made questionnaire, analyzed the influence of study motivation on specialty recognition and their performance in the study, and proposed the improvement of study effect through enhancing honesty education and stimulating study moti-vation, so as to achieve the cultivation goal.
Fujiwara, Toshiaki; Ozaki, Hiroshi; Taniguchi, Tetsuya
2011-01-01
Donald Saari conjectured that the N-body motion with constant configurational measure is a motion with fixed shape. We will show that this conjecture is true for planar equal-mass three-body problem under the strong force potential $\\sum 1/r_{ij}^2$.
Order 1/N2 test of the Maldacena conjecture : cancellation of the one-loop Weyl anomaly.
Mansfield, Paul; Nolland, David
2000-01-01
We test the Maldacena conjecture for type IIB String Theory/ N=4 Yang-Mills by calculating the one-loop corrections in the bulk theory to the Weyl anomaly of the boundary CFT when the latter is coupled to a Ricci-flat metric. The contributions cancel within each supermultiplet, in agreement with the conjecture.
Goodman, Charles H.
1971-01-01
Motivation is an area which has received some systematic psychological study only in the past seventy years. It is the purpose of this article to explore and examine some of the knowledge that has been acquired and to see how this knowledge may be applied. (24 references) (Author/NH)
2016-01-01
In this paper, at first two new functions are given then three new functions are developed based on the first two functions. Using these functions accompanied by a novel method, we make a conjecture to prove "every even integer greater than 2 can be represented by the sum of two prime numbers".In order to make the proof, firstly a simple function as $h(n)=n-\\Sigma_{j=0}^{k-1}(r_{1}^{j})^2+f(k)$ is made for each even integer $n$ and is then extended as function $\\hat{h}(n)=n-\\Sigma_{j=0}^{k-1}...
Sabihi, Ahmad
2016-01-01
In this paper, at first two new functions are given then three new functions are developed based on the first two functions. Using these functions accompanied by a novel method, we make a conjecture to prove "every even integer greater than 2 can be represented by the sum of two prime numbers".In order to make the proof, firstly a simple function as $h(n)=n-\\Sigma_{j=0}^{k-1}(r_{1}^{j})^2+f(k)$ is made for each even integer $n$ and is then extended as function $\\hat{h}(n)=n-\\Sigma_{j=0}^{k-1}...
Institute of Scientific and Technical Information of China (English)
2000-01-01
Zheng Min(Maggie):Initiation of the discus-sion topicDear Mr.Ma,I’m very sorry for this late initia-tion of discussion topics.Just come from one countyof Inner Mongolia near the city of Chi Feng.There isreally a lack of competent teachers of English in ruralareas,and in astonishment I saw many who barelyspeak English teaches English in middle schools.Asfor the topic of discussion,I’d like to focus on learn-er’s motivation,which is a vital factor in successfullearning.It is well known that motivation is classi-fied by Gardner & Lambert(1972)into"integrative"and"instrumental"ones.Other categorization in-
National Research Council Canada - National Science Library
Marina Yepifanova; Boris Zhelezovsky
2012-01-01
It is theoretically proved and experimentally possibility of maintenance of continuity of formation of socially significant hierarchy of motives of the learning of senior pupils by means of multimedia...
Numerical Tests of the Cosmic Censorship Conjecture with Collisionless Matter Collapse
Okounkova, Maria; Hemberger, Daniel; Scheel, Mark
2016-03-01
We present our results of numerical tests of the weak cosmic censorship conjecture (CCC), which states that generically, singularities of gravitational collapse are hidden within black holes, and the hoop conjecture, which states that black holes form when and only when a mass M gets compacted into a region whose circumference in every direction is C <= 4 πM . We built a smooth particle methods module in SpEC, the Spectral Einstein Code, to simultaneously evolve spacetime and collisionless matter configurations. We monitor RabcdRabcd for singularity formation, and probe for the existence of apparent horizons. We include in our simulations the prolate spheroid configurations considered in Shapiro and Teukolsky's 1991 numerical study of the CCC. This research was partially supported by the Dominic Orr Fellowship at Caltech.
Black objects and hoop conjecture in five-dimensional space-time
Energy Technology Data Exchange (ETDEWEB)
Yamada, Yuta; Shinkai, Hisa-aki, E-mail: m1m08a26@info.oit.ac.j, E-mail: shinkai@is.oit.ac.j [Faculty of Information Science and Technology, Osaka Institute of Technology, 1-79-1 Kitayama, Hirakata, Osaka 573-0196 (Japan)
2010-02-21
We numerically investigated the sequences of initial data of a thin spindle and a thin ring in five-dimensional space-time in the context of the cosmic censorship conjecture. We modeled the matter in non-rotating homogeneous spheroidal or toroidal configurations under the momentarily static assumption, solved the Hamiltonian constraint equation and searched the apparent horizons. We discussed when S{sup 3} (black-hole) or S{sup 1} x S{sup 2} (black-ring) horizons ('black objects') are formed. By monitoring the location of the maximum Kretchmann invariant, an appearance of 'naked singularity' or 'naked ring' under special situations is suggested. We also discuss the validity of the hyper-hoop conjecture using a minimum area around the object, and show that the appearance of the ring horizon does not match with this hoop.
Uniform asymptotics for the full moment conjecture of the Riemann zeta function
Hiary, Ghaith A
2011-01-01
Conrey, Farmer, Keating, Rubinstein, and Snaith recently conjectured formulas for the full asymptotics of the moments of $L$-functions. In the case of the Riemann zeta function, their conjecture states that the $2k$-th absolute moment of zeta on the critical line is asymptotically given by a certain $2k$-fold residue integral. This residue integral can be expressed as a polynomial of degree $k^2$, whose coefficients are given in exact form by elaborate and complicated formulas. In this article, uniform asymptotics for roughly the first $k$ coefficients of the moment polynomial are derived. Numerical data to support our asymptotic formula are presented. An application to bounding the maximal size of the zeta function is considered.
Cvijović, Djurdje
2010-01-01
Borwein and Broadhurst, using experimental-mathematics techniques, in 1998 identified numerous hyperbolic 3-manifolds whose volumes are rationally related to values of various Dirichlet L series $\\textup{L}_{d}(s)$. In particular, in the simplest case of an ideal tetrahedron in hyperbolic space, they conjectured that a dilogarithmic integral representing the volume equals to $\\textup{L}_{-7}(2)$. Here we have provided a formal proof of this conjecture which has been recently numerically verified (to at least 19,995 digits, using 45 minutes on 1024 processors) in cutting-edge computing experiments. The proof essentially relies on the results of Zagier on the formula for the value of Dedekind zeta function $\\zeta_{\\mathbb{K}}(2)$ for an arbitrary field $\\mathbb{K}$.
Conjecture on imminent earthquake prediction --- from shaving foam to cloud patterns
Liu, Xin
2013-01-01
A conjecture on imminent earthquake prediction is presented. Drastic geological deformations of crustal rock strata taking place immediately (hours/days) before an earthquake may cause fast air or gas emission/absorption vertically in between ground and sky. I conjecture, inspired by an observation of strange patterns appearing on shaving foam, that this fast movement of air fluid may produce unusual cloud patterns at interfaces between atmosphere levels. This air movement is vertical and drastic, different from the horizontal and moderate meteorological air movement, hence its caused cloud patterns are expected to be different from meteorological cloud patterns. This provides a possible origin for the so-called earthquake cloud. Recognition of different earthquake cloud patterns may provide a practical way to estimate location, magnitude and strength of geological deformations of rock strata, and hence a method with support of physics for imminent earthquake prediction. In the end of this paper an experiment...
Black Objects and Hoop Conjecture in Five-dimensional Space-time
Yamada, Yuta
2009-01-01
We numerically investigated the sequences of initial data of thin spindle and thin ring in five-dimensional space-time in the context of the cosmic censorship conjecture. We modeled the matter in non-rotating homogeneous spheroidal or toroidal configurations under the momentarily static assumption, solved the Hamiltonian constraint equation, and searched the apparent horizon. We found both $S^3$ (black hole) and $S^2\\times S^1$ (black ring) horizons ("black objects"), only when the matter configuration is not sharp. By monitoring the location of the maximum Kretchmann invariant, an appearance of `naked singularity' or `naked ring' under the special situations is suggested. We also discuss the validity of the {\\it hyper-hoop} conjecture using minimum {\\it area} around the object, and show that the appearance of the ring horizon does not match with this hoop.
Axion experiments to algebraic geometry: Testing quantum gravity via the Weak Gravity Conjecture
Heidenreich, Ben; Reece, Matthew; Rudelius, Tom
2016-06-01
Common features of known quantum gravity theories may hint at the general nature of quantum gravity. The absence of continuous global symmetries is one such feature. This inspired the Weak Gravity Conjecture, which bounds masses of charged particles. We propose the Lattice Weak Gravity Conjecture, which further requires the existence of an infinite tower of particles of all possible charges under both abelian and nonabelian gauge groups and directly implies a cutoff for quantum field theory. It holds in a wide variety of string theory examples and has testable consequences for the real world and for pure mathematics. We sketch some implications of these ideas for models of inflation, for the QCD axion (and LIGO), for conformal field theory, and for algebraic geometry.
Axion Experiments to Algebraic Geometry: Testing Quantum Gravity via the Weak Gravity Conjecture
Heidenreich, Ben; Rudelius, Tom
2016-01-01
Common features of known quantum gravity theories may hint at the general nature of quantum gravity. The absence of continuous global symmetries is one such feature. This inspired the Weak Gravity Conjecture, which bounds masses of charged particles. We propose the Lattice Weak Gravity Conjecture, which further requires the existence of an infinite tower of particles of all possible charges under both abelian and nonabelian gauge groups and directly implies a cutoff for quantum field theory. It holds in a wide variety of string theory examples and has testable consequences for the real world and for pure mathematics. We sketch some implications of these ideas for models of inflation, for the QCD axion (and LIGO), for conformal field theory, and for algebraic geometry.
Harvey, Peter
2016-07-01
In the field of research into the treatment of problem gambling, researchers have been attempting to identify the treatment pathways that are effective in remediating gambling disorder among people seeking help. In spite of these efforts, research results remain equivocal in relation to which components of the various treatment options are effective, echoing the familiar claim that all psychotherapy treatments are effective, the Dodo Bird Conjecture.This recent tendency towards the revival of the Dodo Bird Conjecture in the field of gambling research is due to factors ranging from a continuing lack of clarity about the effective components of treatments, subjective therapist effects and the lack of validated repeated measures of outcome to assess changes in self-reported data on gambling urge: anxiety, depression and changes in the 'gambling disorder' diagnosis over time.
Violating the quantum focusing conjecture and quantum covariant entropy bound in d ⩾ 5 dimensions
Fu, Zicao; Koeller, Jason; Marolf, Donald
2017-09-01
We study the quantum focussing conjecture (QFC) in curved spacetime. Noting that quantum corrections from integrating out massive fields generally induce a Gauss-Bonnet term, we study Einstein-Hilbert-Gauss-Bonnet gravity and show for d≥slant 5 spacetime dimensions that weakly-curved solutions can violate the associated QFC for either sign of the Gauss-Bonnet coupling. The nature of the violation shows that—so long as the Gauss-Bonnet coupling is non-zero—it will continue to arise for local effective actions containing arbitrary further higher curvature terms, and when gravity is coupled to generic d≥slant 5 theories of massive quantum fields. The argument also implies violations of a recently-conjectured form of the generalized covariant entropy bound. The possible validity of the QFC and covariant entropy bound in d≤slant 4 spacetime dimensions remains open.
The prime graph conjecture for integral group rings of some alternatings groups
Directory of Open Access Journals (Sweden)
Mohamed Salim
2013-03-01
Full Text Available We investigate the classical Zassenhaus Conjecture (ZC for integral group rings of alternating groups A9 and A10. Even the question (ZC remains open as no counterexample is known up to date, it been confirmed for special types of groups such as nilpotent groups by Roggenkamp, Scot and Weiss. However, a new method based on the partial augmentation of torsion units been established by Luthar and Passi to confirm the (ZC for A5. Later a weaker version of (ZC was proposed in 2007, we call it the Prime Graph Conjecture (PGC about the Gruenberg-Kegel (prime graph of the group of all normalized units of the integral group ring of a finite group. Recently, the (PGC has a positive answer for solvable groups, Frobenius groups and several simple groups. Here, as a consequence of our results, we confirm the (PGC for integral group rings of alternating groups An for all n<11.
From wormhole to time machine Comments on Hawking's Chronology Protection Conjecture
Visser, B M
1993-01-01
The recent interest in ``time machines'' has been largely fueled by the apparent ease with which such systems may be formed in general relativity, given relatively benign initial conditions such as the existence of traversable wormholes or of infinite cosmic strings. This rather disturbing state of affairs has led Hawking to formulate his Chronology Protection Conjecture, whereby the formation of ``time machines'' is forbidden. This paper will use several simple examples to argue that the universe appears to exhibit a ``defense in depth'' strategy in this regard. For appropriate parameter regimes Casimir effects, wormhole disruption effects, and gravitational back reaction effects all contribute to the fight against time travel. Particular attention is paid to the role of the quantum gravity cutoff. For the class of model problems considered it is shown that the gravitational back reaction becomes large before the Planck scale quantum gravity cutoff is reached, thus supporting Hawking's conjecture.
Gopar, V A; Gopar, Victor A.; Mello, Pier A.
1997-01-01
We propose a conjecture that relates the statistical properties of the scattering matrix for quantum chaotic scattering in the presence and in the absence of direct processes. The conjecture has been proved only for one-energy distributions. Here it is verified using numerical simulations in two cases: a) Wigner's time delay distributions for one-dimensional S matrices and the three universality classes; b) the two-energy autocorrelation for one and two-dimensional S matrices. The conjecture is appealing because of its conceptual simplicity; its validity would imply that future calculations could be restricted to the simpler case of no direct processes.
关于Bessis-Moussa-Villani猜想的讨论%On Bessis-Moussa-Villani Conjecture
Institute of Scientific and Technical Information of China (English)
周其生
2013-01-01
本文主要介绍BMV（ Bessis-Moussa-Villiani）猜想提出的背景、意义，及有关学者证明这个猜想的一些有意义的工作，并对BMV猜想的证明思路进行了疏理。%In this paper, we introduce the background significance for puting forward the BMV conjecture , the work doing by some authors who prove the conjecture.Finally, the general train of thought to prove the conjecture is presented.
More about Birkhoff's invariant and Thorne's hoop conjecture for horizons
Energy Technology Data Exchange (ETDEWEB)
Cvetic, M [Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104 (United States); Gibbons, G W; Pope, C N [DAMTP, Centre for Mathematical Sciences, Cambridge University, Wilberforce Road, Cambridge CB3 OWA (United Kingdom)
2011-10-07
A recent precise formulation of the hoop conjecture in four spacetime dimensions is that the Birkhoff invariant {beta} (the least maximal length of any sweepout or foliation by circles) of an apparent horizon of energy E and area A should satisfy {beta} {<=} 4{pi}E. This conjecture together with the cosmic censorship or isoperimetric inequality implies that the length l of the shortest non-trivial closed geodesic satisfies l{sup 2} {<=} {pi}A. We have tested these conjectures on the horizons of all four-charged rotating black hole solutions of ungauged supergravity theories and found that they always hold. They continue to hold in the presence of a negative cosmological constant, and for multi-charged rotating solutions in gauged supergravity. Surprisingly, they also hold for the Ernst-Wild static black holes immersed in a magnetic field, which are asymptotic to the Melvin solution. In five spacetime dimensions we define {beta} as the least maximal area of all sweepouts of the horizon by two-dimensional tori, and find in all cases examined that {beta} (g) {<=} {l_brace}16 {pi}/ 3{r_brace} E, which we conjecture holds quiet generally for apparent horizons. In even spacetime dimensions D = 2N + 2, we find that for sweepouts by the product S{sup 1} x S{sup D-4}, {beta} is bounded from above by a certain dimension-dependent multiple of the energy E. We also find that l{sup D-2} is bounded from above by a certain dimension-dependent multiple of the horizon area A. Finally, we show that l{sup D-3} is bounded from above by a certain dimension-dependent multiple of the energy, for all Kerr-AdS black holes.
Modeling shock waves in an ideal gas: combining the Burnett approximation and Holian's conjecture.
He, Yi-Guang; Tang, Xiu-Zhang; Pu, Yi-Kang
2008-07-01
We model a shock wave in an ideal gas by combining the Burnett approximation and Holian's conjecture. We use the temperature in the direction of shock propagation rather than the average temperature in the Burnett transport coefficients. The shock wave profiles and shock thickness are compared with other theories. The results are found to agree better with the nonequilibrium molecular dynamics (NEMD) and direct simulation Monte Carlo (DSMC) data than the Burnett equations and the modified Navier-Stokes theory.
A Special Case Of A Conjecture By Widom With Implications To Fermionic Entanglement Entropy
Helling, R C; Spitzer, W L
2009-01-01
We prove a special case of a conjecture by Harold Widom. More precisely, we establish the leading and next-to-leading term of a semi-classical expansion of the trace of the square of certain integral operators on the Hilbert space $L^2(\\R^d)$. As already observed by Gioev and Klich, this implies a logarithmically enhanced "area law" of the entanglement-entropy of the free Fermi gas in its ground state for large scales.
On a directed variation of the 1-2-3 and 1-2 Conjectures
DEFF Research Database (Denmark)
Barme, Emma; Bensmail, Julien; Przybyło, Jakub;
2016-01-01
In this paper, we consider the following question, which stands as a directed analogue of the well-known 1-2-3 Conjecture: Given any digraph D with no arc uv verifying d+(u) = d¯(v) = 1, is it possible to weight the arcs of D with weights among ⟨1; 2; 3⟩ so that, for every arc uv of D, the sum of...
Proofs to two inequality conjectures for a point on the plane of a triangle
Directory of Open Access Journals (Sweden)
Fangjian Huang
2016-02-01
Full Text Available Abstract We prove two conjectures for a point on the plane of a triangle presented in (Liu in J. Math. Inequal. 8(3:597-611, 2014, doi: 10.1007/s11590-013-0708-4 by using the successive difference substitution algorithm NEWTSDS. Compared with the original proof, the new one is simpler and more easily understood. Similar problems can be treated with the same procedure.
The Threshold for the Erd(o)s, Jacobson and Lehel Conjecture to Be True
Institute of Scientific and Technical Information of China (English)
Jiong Sheng LI; Jian Hua YIN
2006-01-01
Let σ(k, n) be the smallest even integer such that each n-term positive graphic sequence with term sum at least σ(k, n) can be realized by a graph containing a clique of k + 1 vertices. Erd(o)s et al. (Graph Theory, 1991, 439-449) conjectured that σ(k, n) = (k-1)(2n-k) + 2. Li et al. (Science in China, 1998, 510-520) proved that the conjecture is true for k≥5 and n≥(k2) + 3, and raised the problem of determining the smallest integer N(k) such that the conjecture holds for n ≥ N(k). They also determined the values of N(k) for 2 ≤ k ≤ 7, and proved that 「5k-1/2(」) ≤ N(k) ≤ (k2) + 3 for k ≥ 8. In this paper, we determine the exact values of σ(k, n) for n ≥ 2k+3 and k ≥6. Therefore, the problem of determining σ(k,n) is completely solved. In addition, we prove as a corollary that N(k)= 「5k-1/2(」) for k≥6.
The volume conjecture, perturbative knot invariants, and recursion relations for topological strings
Dijkgraaf, Robbert; Fuji, Hiroyuki; Manabe, Masahide
2011-08-01
We study the relation between perturbative knot invariants and the free energies defined by topological string theory on the character variety of the knot. Such a correspondence between SL(2;C) Chern-Simons gauge theory and the topological open string theory was proposed earlier on the basis of the volume conjecture and AJ conjecture. In this paper we discuss this correspondence beyond the subleading order in the perturbative expansion on both sides. In the computation of the perturbative invariants for the hyperbolic 3-manifold, we adopt the state integral model for the hyperbolic knots, and the factorized AJ conjecture for the torus knots. On the other hand, we iteratively compute the free energies on the character variety using the Eynard-Orantin topological recursion relation. We discuss the correspondence for the figure eight knot complement and the once punctured torus bundle over S with the monodromy LR up to the fifth order. For the torus knots, we find trivial the recursion relations on both sides.
The volume conjecture, perturbative knot invariants, and recursion relations for topological strings
Energy Technology Data Exchange (ETDEWEB)
Dijkgraaf, Robbert, E-mail: r.h.dijkgraaf@uva.n [Institute for Theoretical Physics and KdV Institute for Mathematics, University of Amsterdam, Spui 21, 1012 WX Amsterdam (Netherlands); Fuji, Hiroyuki, E-mail: fuji@th.phys.nagoya-u.ac.j [Department of Physics, Nagoya University, Nagoya 464-8602 (Japan); Manabe, Masahide, E-mail: d07002p@math.nagoya-u.ac.j [Graduate School of Mathematics, Nagoya University, Nagoya 464-8602 (Japan)
2011-08-01
We study the relation between perturbative knot invariants and the free energies defined by topological string theory on the character variety of the knot. Such a correspondence between SL(2;C) Chern-Simons gauge theory and the topological open string theory was proposed earlier on the basis of the volume conjecture and AJ conjecture. In this paper we discuss this correspondence beyond the subleading order in the perturbative expansion on both sides. In the computation of the perturbative invariants for the hyperbolic 3-manifold, we adopt the state integral model for the hyperbolic knots, and the factorized AJ conjecture for the torus knots. On the other hand, we iteratively compute the free energies on the character variety using the Eynard-Orantin topological recursion relation. We discuss the correspondence for the figure eight knot complement and the once punctured torus bundle over S{sup 1} with the monodromy L{sup 2}R up to the fifth order. For the torus knots, we find trivial the recursion relations on both sides.
The Volume Conjecture, Perturbative Knot Invariants, and Recursion Relations for Topological Strings
Dijkgraaf, Robbert; Manabe, Masahide
2010-01-01
We study the relation between perturbative knot invariants and the free energies defined by topological string theory on the character variety of the knot. Such a correspondence between SL(2;C) Chern-Simons gauge theory and the topological open string theory was proposed earlier on the basis of the volume conjecture and AJ conjecture. In this paper we discuss this correspondence beyond the subleading order in the perturbative expansion on both sides. In the computation of the perturbative invariants for the hyperbolic 3-manifold, we adopt the state integral model for the hyperbolic knots, and the factorized AJ conjecture for the torus knots. On the other hand, we iteratively compute the free energies on the character variety using the Eynard-Orantin topological recursion relation. We check the correspondence for the figure eight knot complement and the once punctured torus bundle over S^1 with the holonomy L^2R up to the fourth order. For the torus knots, we find trivial the recursion relations on both sides.
An Orthogonal Test of the $L$-functions Ratios Conjecture, II
Miller, Steven J
2009-01-01
Recently Conrey, Farmer, and Zirnbauer developed the L-functions Ratios conjecture, which gives a recipe that predicts a wealth of statistics, from moments to spacings between adjacent zeros and values of L-functions. The problem with this method is that several of its steps involve ignoring error terms of size comparable to the main term; amazingly, the errors seem to cancel and the resulting prediction is expected to be accurate up to square-root cancellation. We prove the accuracy of the Ratios Conjecture's prediction for the 1-level density of families of cuspidal newforms of constant sign (up to square-root agreement for support in (-1,1), and up to a power savings in (-2,2)), and discuss the arithmetic significance of the lower order terms. This is the most involved test of the Ratios Conjecture's predictions to date, as it is known that the error terms dropped in some of the steps do not cancel, but rather contribute a main term! Specifically, these are the non-diagonal terms in the Petersson formula, ...
Understanding Teenagers' motivation in Participatory Design
DEFF Research Database (Denmark)
Iversen, Ole Sejer; Dindler, Christian; Hansen, Elin
2014-01-01
Engaging children in the design of digital technology is one of the core strands in Child-Computer Interaction literature. Nevertheless, only few studies explore how teenagers as a distinct user group are engaged in Participatory Design activities. Based on a case study comprising ten Participatory......-established PD tools and techniques, a deeper understanding of teenagers’ motivation and motives is essential to understand how tools and techniques can made to support teenagers motivation. We outline a Cultural Historical Activity Theoretical approach to teenagers’ motives and motivation as a frame...
Directory of Open Access Journals (Sweden)
Vitaly Kaszuba
2016-08-01
Full Text Available Purpose: to carry out the analysis of results of researches of the forming experiment, and in particular, indicators of motive activity of respondents. Material & Methods: contingent: pupils of "Balty vocational-technical agrarian school" of Balty of the Odessa Region – 40 girls of the I course who do not go in for sports; methods: analysis of literature, pedagogical methods of the research, questioning, methods of mathematical statistics. Results: the data are analyzed, which are obtained in the forming experiment on the determination of level of motive activity by means of Framingham technique as one of the criteria of efficiency of introduction of the technology, which is directed to the improvement of professionally significant physical qualities of pupils of vocational-technical schools of clothing manufacture. Results of the questioning, which is directed to the identification subjective opinions of respondents concerning their motive activity, are analyzed. The results of questioning of pupils about the main conditions are presented, which are necessary for the involvement of students to the active physical improvement. Conclusions: the received results confirm the efficiency of the developed and introduced technology.
A proof of a conjecture by Schweizer on the Drinfeld modular polynomial ΦT (X, Y )
DEFF Research Database (Denmark)
Bassa, Alp; Beelen, Peter
2011-01-01
In this paper we prove a conjecture by Schweizer on the reduction of the Drinfeld modular polynomial ΦT (X, Y ) modulo T − 1. The proof mainly involves manipulations of binomial coefficients in characteristic p....
Motivation in Beyond Budgeting: A Motivational Paradox?
DEFF Research Database (Denmark)
Sandalgaard, Niels; Bukh, Per Nikolaj
In this paper we discuss the role of motivation in relation to budgeting and we analyse how the Beyond Budgeting model functions compared with traditional budgeting. In the paper we focus on budget related motivation (and motivation in general) and conclude that the Beyond Budgeting model...... is a motivational paradox....
Mixed motives and algebraic K-theory
Jannsen, Uwe
1990-01-01
The relations that could or should exist between algebraic cycles, algebraic K-theory, and the cohomology of - possibly singular - varieties, are the topic of investigation of this book. The author proceeds in an axiomatic way, combining the concepts of twisted Poincaré duality theories, weights, and tensor categories. One thus arrives at generalizations to arbitrary varieties of the Hodge and Tate conjectures to explicit conjectures on l-adic Chern characters for global fields and to certain counterexamples for more general fields. It is to be hoped that these relations ions will in due course be explained by a suitable tensor category of mixed motives. An approximation to this is constructed in the setting of absolute Hodge cycles, by extending this theory to arbitrary varieties. The book can serve both as a guide for the researcher, and as an introduction to these ideas for the non-expert, provided (s)he knows or is willing to learn about K-theory and the standard cohomology theories of algebraic varietie...
Agent Models for Self-Motivated Home-Assistant Bots
Merrick, Kathryn; Shafi, Kamran
2010-01-01
Modern society increasingly relies on technology to support everyday activities. In the past, this technology has focused on automation, using computer technology embedded in physical objects. More recently, there is an expectation that this technology will not just embed reactive automation, but also embed intelligent, proactive automation in the environment. That is, there is an emerging desire for novel technologies that can monitor, assist, inform or entertain when required, and not just when requested. This paper presents three self-motivated, home-assistant bot applications using different self-motivated agent models. Self-motivated agents use a computational model of motivation to generate goals proactively. Technologies based on self-motivated agents can thus respond autonomously and proactively to stimuli from their environment. Three prototypes of different self-motivated agent models, using different computational models of motivation, are described to demonstrate these concepts.
Carpenter, Serena; Hoag, Anne; Grant, August E.; Bowe, Brian J.
2015-01-01
The newsroom is a powerful influence in a journalist's identity formation. Research has yet to verify the socializing impact of academia. This research utilized the quantitative survey method applying it to undergraduate journalism students (n = 798) to assess how academic status relates to students' degree motivations, life values, and technology…
Carpenter, Serena; Hoag, Anne; Grant, August E.; Bowe, Brian J.
2015-01-01
The newsroom is a powerful influence in a journalist's identity formation. Research has yet to verify the socializing impact of academia. This research utilized the quantitative survey method applying it to undergraduate journalism students (n = 798) to assess how academic status relates to students' degree motivations, life values, and technology…
Cheruvalath, Reena
2012-01-01
This study has been conducted to show that there is a recent trend in engineering colleges in India that students who are considered to be highly intelligent show poor academic performance during their 1st year. This article is proposed to examine the role of motivation factors such as teaching methods and learning material in the academic…
Mawanda, Haruna Juko
2012-01-01
The primary purpose of this nonexperimental, correlational, and descriptive quantitative study research was to gain an empirical understanding of the effects of transformational leadership and contingent reward as extrinsic motivation on employee satisfaction with leadership and leadership effectiveness in virtual team workplace environments.…
Proof of a Conjecture on Contextuality in Cyclic Systems with Binary Variables
Kujala, Janne V.; Dzhafarov, Ehtibar N.
2016-03-01
We present a proof for a conjecture previously formulated by Dzhafarov et al. (Found Phys 7:762-782, 2015). The conjecture specifies a measure for the degree of contextuality and a criterion (necessary and sufficient condition) for contextuality in a broad class of quantum systems. This class includes Leggett-Garg, EPR/Bell, and Klyachko-Can-Binicioglu-Shumovsky type systems as special cases. In a system of this class certain physical properties q1,ldots ,qn are measured in pairs ( qi,qj) ; every property enters in precisely two such pairs; and each measurement outcome is a binary random variable. Denoting the measurement outcomes for a property qi in the two pairs it enters by Vi and Wi, the pair of measurement outcomes for ( qi,qj) is ( Vi,Wj) . Contextuality is defined as follows: one computes the minimal possible value Δ 0 for the sum of Pr [ Vinot =Wi] (over i=1,ldots ,n) that is allowed by the individual distributions of Vi and Wi; one computes the minimal possible value Δ _{min } for the sum of Pr [ Vinot =Wi] across all possible couplings of (i.e., joint distributions imposed on) the entire set of random variables V1,W1,ldots ,Vn,Wn in the system; and the system is considered contextual if Δ _{min }>Δ 0 (otherwise Δ _{min }=Δ 0). This definition has its justification in the general approach dubbed Contextuality-by-Default, and it allows for measurement errors and signaling among the measured properties. The conjecture proved in this paper specifies the value of Δ _{min }-Δ 0 in terms of the distributions of the measurement outcomes ( Vi,Wj).
Abelian surfaces, Kummer surfaces and the non-Archimedean Hodge-D-conjecture
Sreekantan, Ramesh
2011-01-01
We construct new elements in the higher Chow group CH2(A,1) of a principally polarized Abelian surface over a non Archimedean local field, which generalize an element constructed by Collino. These elements are constructed using a generalization, due to Birkenhake and Wilhelm, of a classical construction of Humbert. They can be used to prove the non-Archimedean Hodge-D-conjecture - namely, the surjectivity of the boundary map in the localization sequence - in the case when the Abelian surface has good and ordinary reduction.
Adjamagbo Determinant and Serre conjecture for linear groups over Weyl algebras
Adjamagbo, Kossivi
2008-01-01
Thanks to the theory of determinants over an Ore domain, also called Adjamagbo determinant by the Russian school of non commutative algebra, we extend to any Weyl algebra over a field of characteristic zero Suslin theorem solving what Suslin himself called the $K_1$-analogue of the well-known Serre Conjecture and asserting that for any integer $n$ greater than 2, any $n$ by $n$ matrix with coefficients in any algebra of polynomials over a field and with determinant one is the product of eleme...
A Note on a Conjecture for Balanced Elementary Symmetric Boolean Functions
Su, Wei; Pott, Alexander
2012-01-01
Cusick {\\it et al.} conjectured that the elementary symmetric Boolean functions of the form $\\sigma_{2^{t+1}l-1, 2^t}$ are the only balanced ones in 2008. In this note, by analyzing the weight of $\\sigma_{n, 2^t}$ and $\\sigma_{n, d}$, we prove that ${\\rm wt}(\\sigma_{n, d})<2^{n-1}$ holds in most cases. According to the remainder of modulo 4, we consider the weight of $\\sigma_{n, d}$ from two aspects: $n\\equiv 3({\\rm mod\\}4)$ and $n\
Campos, M
2014-01-01
Presently, the inclusion of the vacuum energy in the energy momentum tensor, and the inclusion of the extra dimensions in the space-time, can not be rule out of the research in gravitation. In this work we study the influence of the vacuum energy in the collapse of a stellar fluid process, and consequently for the cosmic censorship conjecture, considering a homogeneous and isotropic space-time with arbitrary number of dimensions. We discuss the active gravitational mass of the black hole formed, where the vacuum energy and the number of dimensions has a crucial role in the process.
The Cosmic Censorship Conjecture in a Higher Dimensional Spacetime and Λ
Campos, M.
2016-03-01
Presently, the inclusion of the vacuum energy in the energy momentum tensor, and the inclusion of the extra dimensions in the spacetime, can not be rule out of the research in gravitation. In this work we study the influence of the vacuum energy in the collapsing process of a stellar fluid, and consequently for the cosmic censorship conjecture, considering a homogeneous and isotropic spacetime with arbitrary number of dimensions. We discuss the active gravitational mass of the black hole formed, where the vacuum energy and the number of dimensions has a crucial role in the process.
The Endpoint of Black Ring Instabilities and the Weak Cosmic Censorship Conjecture
Figueras, Pau; Tunyasuvunakool, Saran
2015-01-01
We produce the first concrete evidence that violation of the weak cosmic censorship conjecture can occur in asymptotically flat spaces of five dimensions by numerically evolving perturbed black rings. For certain thin rings, we identify a new, elastic-type instability dominating the evolution, causing the system to settle to a spherical black hole. However, for sufficiently thin rings the Gregory-Laflamme mode is dominant, and the instability unfolds similarly to that of black strings, where the horizon develops a structure of bulges connected by necks which become ever thinner over time.
End Point of Black Ring Instabilities and the Weak Cosmic Censorship Conjecture
Figueras, Pau; Kunesch, Markus; Tunyasuvunakool, Saran
2016-02-01
We produce the first concrete evidence that violation of the weak cosmic censorship conjecture can occur in asymptotically flat spaces of five dimensions by numerically evolving perturbed black rings. For certain thin rings, we identify a new, elastic-type instability dominating the evolution, causing the system to settle to a spherical black hole. However, for sufficiently thin rings the Gregory-Laflamme mode is dominant, and the instability unfolds similarly to that of black strings, where the horizon develops a structure of bulges connected by necks which become ever thinner over time.
Kottwitz's nearby cycles conjecture for a class of unitary Shimura varieties
Rostami, Sean
2011-01-01
This paper proves that the nearby cycles complex on a certain family of PEL local models is central with respect to the convolution product of sheaves on the corresponding affine flag variety. As a corollary, the semisimple trace function defined using the action of Frobenius on that nearby cycles complex is, via the sheaf-function dictionary, in the center of the corresponding Iwahori-Hecke algebra. This is commonly referred to as Kottwitz's conjecture. The reductive groups associated to the PEL local models under consideration are unramified unitary similitude groups with even dimension. The proof follows the method of [Haines-Ngo 2002].
Rings of skew polynomials and Gel'fand-Kirillov conjecture for quantum groups
Iohara, Kenji; Malikov, Feodor
1993-01-01
We introduce and study action of quantum groups on skew polynomial rings and related rings of quotients. This leads to a ``q-deformation'' of the Gel'fand-Kirillov conjecture which we partially prove. We propose a construction of automorphisms of certain non-commutaive rings of quotients coming from complex powers of quantum group generators; this is applied to explicit calculation of singular vectors in Verma modules over $U_{q}(\\gtsl_{n+1})$. We finally give a definition of a $q-$connection...
2016-01-01
We approach a new proof of the strong Goldbach's conjecture for sufficiently large even integers by applying the Dirichlet's series. Using the Perron formula and the Residue Theorem in complex variable integration, one could show that any large even integer is demonstrated as a sum of two primes. In this paper,the Riemann Hypothesis is assumed to be true in throughout the paper. A novel function is defined on the natural numbers set.This function is a typical sieve function.Then based on this...
Non-vanishing of L-functions, the Ramanujan conjecture, and families of Hecke characters
Blomer, Valentin
2011-01-01
We prove a non-vanishing result for families of $\\GL_n\\times\\GL_n$ Rankin-Selberg $L$-functions in the critical strip, as one factor runs over twists by Hecke characters. As an application, we simplify the proof, due to Luo, Rudnick, and Sarnak, of the best known bounds towards the Generalized Ramanujan Conjecture at the infinite places for cusp forms on $\\GL_n$. A key ingredient is the regularization of the units in residue classes by the use of an Arakelov ray class group.
A Collatz-type conjecture on the set of rational numbers
Javaheri, Mohammad
2010-01-01
Define $\\theta(x)=(x-1)/3$ if $x\\geq 1$, and $\\theta(x)=2x/(1-x)$ if $x<1$. We conjecture that the orbit of every positive rational number ends in 0. In particular, there does not exist any positive rational fixed point for a map in the semigroup $\\Omega$ generated by the maps $3x+1$ and $x/(x+2)$. In this paper, we prove that the asymptotic density of the set of elements in $\\Omega$ that have rational fixed points is zero.
Sabihi, Ahmad
2016-01-01
We approach a new proof of the strong Goldbach's conjecture for sufficiently large even integers by applying the Dirichlet's series. Using the Perron formula and the Residue Theorem in complex variable integration, one could show that any large even integer is demonstrated as a sum of two primes. In this paper,the Riemann Hypothesis is assumed to be true in throughout the paper. A novel function is defined on the natural numbers set.This function is a typical sieve function.Then based on this...
Fate of stringy AdS vacua and the weak gravity conjecture
Danielsson, Ulf; Dibitetto, Giuseppe
2017-07-01
Ooguri and Vafa [arXiv:1610.01533] have recently proposed a stronger version of the weak gravity conjecture (WGC), based on which they concluded that all those nonsupersymmetric AdS vacua that can be embedded within a consistent theory of quantum gravity necessarily develop instabilities. In this paper we further elaborate on this proposal by arguing that the aforementioned instabilities have a perturbative nature and arise from the crucial interplay between the closed and the open string sectors of the theory.
A Conjecture Regarding the Extremal Values of Graph Entropy Based on Degree Powers
Directory of Open Access Journals (Sweden)
Kinkar Chandra Das
2016-05-01
Full Text Available Many graph invariants have been used for the construction of entropy-based measures to characterize the structure of complex networks. The starting point has been always based on assigning a probability distribution to a network when using Shannon’s entropy. In particular, Cao et al. (2014 and 2015 defined special graph entropy measures which are based on degrees powers. In this paper, we obtain some lower and upper bounds for these measures and characterize extremal graphs. Moreover we resolve one part of a conjecture stated by Cao et al.
How Not to Win a Million Dollars: A Counterexample to a Conjecture of L. Breiman
Hayes, Thomas P
2011-01-01
Consider a gambling game in which we are allowed to repeatedly bet a portion of our bankroll at favorable odds. We investigate the question of how to minimize the expected number of rounds needed to increase our bankroll to a given target amount. Specifically, we disprove a 50-year old conjecture of L. Breiman, that there exists a threshold strategy that optimizes the expected number of rounds; that is, a strategy that always bets to try to win in one round whenever the bankroll is at least a certain threshold, and that makes Kelly bets (a simple proportional betting scheme) whenever the bankroll is below the threshold.
Proof of Murphy-Cohen Conjecture on One-Dimensional Hard Ball Systems
Institute of Scientific and Technical Information of China (English)
Lizhou CHEN
2007-01-01
We prove the Murphy and Cohen's conjecture that the maximum number of collisions of n+1 elastic particles moving freely on a line is n(n+1)/2 if no interior particle has mass less than the arithmetic mean of the masses of its immediate neighbors.In fact,we prove the stronger result that,for the same conclusion,the condition that no interior particle has mass less than the geometric mean,rather than the arithmetic mean,of the masses of its immediate neighbors suffices.
Potential wells with a unique brake orbit. Counterexamples to a conjecture by H. Seifert
Giambo', R; Piccione, P
2012-01-01
In this paper we prove the existence of real-analytic natural Hamiltonian systems - i.e. where H(q,p)=T(q,p)+V(q) in the 2N-dimensional real space, where N is any integer greater than 1 - with non critical energy levels E for the potential V such that the sublevel E of V is homeomorphic to the N-dimensional disk, and that only one brake orbit of energy E exists. A famous conjecture formulated by H. Seifert in 1948 claimed the existence of at least N distinct brake orbits for this situation.
Conjecture on reflectionlessness of blood-vascular system as a wave-conducting medium
Goldobin, D. S.; Mizeva, I. A.
2017-06-01
Our research is related to the employment of photoplethysmography (PPG) and laser Doppler flowmetry (LDF) techniques (measuring the blood volume and flux, respectively) for the peripheral vascular system. We derive the governing equations of the wave dynamics for the case of extremely inhomogeneous parameters. We argue for the conjecture that the blood-vascular system as a wave-conducting medium should be nearly reflection-free. With the reflectionlessness condition, one can find the general solution to the governing equation and, on the basis of this solution, analyse the relationships between PPG- and LDF-signals.
Are some packings more equal than others? A direct test of the Edwards conjecture
Martiniani, Stefano; Ramola, Kabir; Chakraborty, Bulbul; Frenkel, Daan
2016-01-01
In the late 1980s, Sir Sam Edwards proposed a possible statistical-mechanical framework to describe the properties of disordered granular materials. A key assumption underlying the theory was that all jammed packings are equally likely. In the intervening years it has never been possible to test this bold hypothesis directly. Here we present simulations that provide direct evidence that at the unjamming point, all packings of soft repulsive particles are equally likely, even though generically, jammed packings are not. Our results therefore support Edwards' original conjecture. We also present evidence that at unjamming the configurational entropy of the system is maximal.
Inflation in a renormalizable cosmological model and the cosmic no-hair conjecture
Energy Technology Data Exchange (ETDEWEB)
Maeda, K.; Stein-Schabes, J. A.; Futamase, T.
1989-05-15
The possibility of having inflation in a renormalizable cosmological model is investigated. The cosmic no-hair conjecture is proved to hold for all Bianchi types except Bianchi type IX. By the use of a conformal transformation on the metric we show that these models are equivalent to the ones described by the Einstein-Hilbert action for gravity minimally coupled to a set of scalar fields with inflationary potentials. Henceforth, we prove that inflationary solutions behave as attractors in solution space, making it a natural event in the evolution of such models.
Inflation in a renormalizable cosmological model and the cosmic no hair conjecture
Maeda, Kei-Ichi; Stein-Schabes, Jaime A.; Futamase, Toshifumi
1988-01-01
The possibility of having inflation in a renormalizable cosmological model is investigated. The Cosmic No Hair Conjecture is proved to hold for all Bianchi types except Bianchi IX. By the use of a conformal transformation on the metric it is shown that these models are equivalent to the ones described by the Einstein-Hilbert action for gravity minimally coupled to a set of scalar fields with inflationary potentials. Henceforth, it is proven that inflationary solutions behave as attractors in solution space, making it a natural event in the evolution of such models.
Motivating the Knowledge Worker
2010-01-01
Herzberg . The Two - factor Theory asserts that motivators and de-motivators are mutually exclusive sets of factors . This research supports...various theories of motivation and the data collected from this effort, the author developed a two -dimensional model of the factors that motivate... Theory X/ Theory Y Two - factor Theory Cognitive Evaluation Theory Operant Conditioning Protection Motivation Theory
The Distribution of Weighted Sums of the Liouville Function and P\\'olya's Conjecture
Humphries, Peter
2011-01-01
Under the assumption of the Riemann Hypothesis, the Linear Independence Hypothesis, and a bound on negative discrete moments of the Riemann zeta function, we prove the existence of a limiting logarithmic distribution of the normalisation of the weighted sum of the Liouville function, $L_{\\alpha}(x) = \\sum_{n \\leq x}{\\lambda(n) / n^{\\alpha}}$, for $0 \\leq \\alpha < 1/2$. Using this, we conditionally show that these weighted sums have a negative bias, but that for each $0 \\leq \\alpha < 1/2$, the set of all $x \\geq 1$ for which $L_{\\alpha}(x)$ is positive has positive logarithmic density. For $\\alpha = 0$, this gives a conditional proof that the set of counterexamples to P\\'olya's conjecture has positive logarithmic density. Finally, when $\\alpha = 1/2$, we conditionally prove that $L_{\\alpha}(x)$ is negative outside a set of logarithmic density zero, thereby lending support to a conjecture of Mossinghoff and Trudgian that this weighted sum is nonpositive for all $x \\geq 17$.
Energy Technology Data Exchange (ETDEWEB)
Hobbs, B.F. [Department of Geography and Environmental Engineering, The Johns Hopkins University, Baltimore, MD (United States); Rijkers, F.A.M. [Office of Energy Regulation DTe, Den Haag (Netherlands)
2004-05-01
The conjectured supply function (CSF) model calculates an oligopolistic equilibrium among competing generating companies (GenCos), presuming that GenCos anticipate that rival firms will react to price increases by expanding their sales at an assumed rate. The CSF model is generalized here to include each generator's conjectures concerning how the price of transmission services (point-to-point service and constrained interfaces) will be affected by the amount of those services that the generator demands. This generalization reflects the market reality that large producers will anticipate that they can favorably affect transmission prices by their actions. The model simulates oligopolistic competition among generators while simultaneously representing a mixed transmission pricing system. This mixed system includes fixed transmission tariffs, congestion-based pricing of physical transmission constraints (represented as a linearized dc load flow), and auctions of interface capacity in a path-based pricing system. Pricing inefficiencies, such as export fees and no credit for counterflows, can be simulated. The model is formulated as a linear mixed complementarity problem, which enables very large market models to be solved. In the second paper of this two-paper series, the capabilities of the model are illustrated with an application to northwest Europe, where transmission pricing is based on such a mixture of approaches.
A conjecture on k-factor-critical and 3-γ-critical graphs
Institute of Scientific and Technical Information of China (English)
无
2010-01-01
For a graph G =(V,E),a subset VS is a dominating set if every vertex in V is either in S or is adjacent to a vertex in S.The domination number γ(G) of G is the minimum order of a dominating set in G.A graph G is said to be domination vertex critical,if γ(G-v) < γ(G) for any vertex v in G.A graph G is domination edge critical,if γ(G ∪ e) < γ(G) for any edge e ∈/E(G).We call a graph G k-γ-vertex-critical(resp.k-γ-edge-critical) if it is domination vertex critical(resp.domination edge critical) and γ(G) = k.Ananchuen and Plummer posed the conjecture:Let G be a k-connected graph with the minimum degree at least k+1,where k 2 and k≡|V|(mod 2).If G is 3-γ-edge-critical and claw-free,then G is k-factor-critical.In this paper we present a proof to this conjecture,and we also discuss the properties such as connectivity and bicriticality in 3-γ-vertex-critical claw-free graph.
The Markus--Yamabe Stability Conjecture and the Generalized Dependence Problem
Guíñez, Víctor
2011-01-01
We study the continuous and discrete versions of the Markus-Yamabe Conjecture for polynomial vector fields in $ \\mathbb{R}^3 $ of the form $ X = \\lambda \\, I + H $, where $ \\lambda $ is a real number, I the identity map, and H a map with nilpotent Jacobian matrix $ JH $. We distinguish the cases when the rows of $ J H $ are linearly dependent over $ \\mathbb{R} $ and when they are linearly independent over $ \\mathbb{R} $. In the dependent continuous case, we give a polynomial family of counterexamples to the Markus-Yamabe conjecture which contains and generalizes that of Cima-Gasull-Ma\\~nosas. Furthermore, we construct a new class of polynomial vector fields in $\\mathbb{R}^3$ having the origin as a global attractor. We also find non--linearly triangularizable vector fields $ X $ for which the origin is a global attractor for both the continuous and the discrete dynamical systems generated by $ X $. In the independent continuous case, we present a family of vector fields that have orbits escaping to infinity.
Nanodeserts: A Conjecture in Nanotechnology to Enhance Quasi-Photosynthetic CO2 Absorption
Directory of Open Access Journals (Sweden)
Wenfeng Wang
2016-01-01
Full Text Available This paper advances “nanodeserts” as a conjecture on the possibility of developing the hierarchical structured polymeric nanomaterials for enhancing abiotic CO2 fixation in the soil-groundwater system beneath deserts (termed as quasi-photosynthetic CO2 absorption. Arid and semiarid deserts ecosystems approximately characterize one-third of the Earth’s land surface but play an unsung role in the carbon cycling, considering the huge potentials of such CO2 absorption to expand insights to the long-sought missing CO2 sink and the naturally unneglectable turbulence in temperature sensitivities of soil respiration it produced. “Nanodeserts” as a reconciled concept not only indicate a conjecture in nanotechnology to enhance quasi-photosynthetic CO2 absorption, but also aim to present to the desert researchers a better understanding of the footprints of abiotic CO2 transport, conversion, and assignment in the soil-groundwater system beneath deserts. Meanwhile, nanodeserts allow a stable temperature sensitivity of soil respiration in deserts by largely reducing the CO2 release above the deserts surface and highlighting the abiotic CO2 fixation beneath deserts. This may be no longer a novelty in the future.
On the homological mirror symmetry conjecture for pairs of pants and affine Fermat hypersurfaces
Sheridan, Nicholas
2010-01-01
The n-dimensional pair of pants is defined to be the complement of n+2 generic hyperplanes in CP^n. We construct an immersed Lagrangian sphere in the pair of pants and compute its endomorphism A_{\\infty} algebra in the Fukaya category. On the level of cohomology, it is an exterior algebra with n+2 generators. It is not formal, and we compute certain higher products in order to determine it up to quasi-isomorphism. This allows us to give some evidence for the homological mirror symmetry conjecture: the pair of pants is conjectured to be mirror to the Landau-Ginzburg model (C^{n+2},W), where W = z_1 ... z_{n+2}. We show that the endomorphism A_{\\infty} algebra of our Lagrangian is quasi-isomorphic to the endomorphism dg algebra of the structure sheaf of the origin in the mirror. This implies similar results for finite covers of the pair of pants, in particular for certain affine Fermat hypersurfaces.
A solid solution to a conjecture on the maximal energy of bipartite bicyclic graphs
Huo, Bofeng; Li, Xueliang; Shi, Yongtang
2011-01-01
The energy of a simple graph $G$, denoted by $E(G)$, is defined as the sum of the absolute values of all eigenvalues of its adjacency matrix. Let $C_n$ denote the cycle of order $n$ and $P^{6,6}_n$ the graph obtained from joining two cycles $C_6$ by a path $P_{n-12}$ with its two leaves. Let $\\mathscr{B}_n$ denote the class of all bipartite bicyclic graphs but not the graph $R_{a,b}$, which is obtained from joining two cycles $C_a$ and $C_b$ ($a, b\\geq 10$ and $a \\equiv b\\equiv 2\\, (\\,\\textmd{mod}\\, 4)$) by an edge. In [I. Gutman, D. Vidovi\\'{c}, Quest for molecular graphs with maximal energy: a computer experiment, {\\it J. Chem. Inf. Sci.} {\\bf41}(2001), 1002--1005], Gutman and Vidovi\\'{c} conjectured that the bicyclic graph with maximal energy is $P^{6,6}_n$, for $n=14$ and $n\\geq 16$. In [X. Li, J. Zhang, On bicyclic graphs with maximal energy, {\\it Linear Algebra Appl.} {\\bf427}(2007), 87--98], Li and Zhang showed that the conjecture is true for graphs in the class $\\mathscr{B}_n$. However, they could not...
Group flow, complex flow, unit vector flow, and the (2+ϵ)-flow conjecture
DEFF Research Database (Denmark)
Thomassen, Carsten
2014-01-01
If F is a (possibly infinite) subset of an abelian group Γ, then we define f(F,Γ) as the smallest natural number such that every f(F,Γ)-edge-connected (finite) graph G has a flow where all flow values are elements in F. We prove that f(F,Γ) exists if and only if some odd sum of elements in F equals...... some even sum. We discuss various instances of this problem. We prove that every 6-edge-connected graph has a flow whose flow values are the three roots of unity in the complex plane. If the edge-connectivity 6 can be reduced, then it can be reduced to 4, and the 3-flow conjecture follows. We prove...... that every 14-edge-connected graph has a flow whose flow values are the five roots of unity in the complex plane. Any such flow is balanced modulo 5. So, if the edge-connectivity 14 can be reduced to 9, then the 5-flow conjecture follows, as observed by F. Jaeger. We use vector flow to prove that, for each...
Testing the ortholog conjecture with comparative functional genomic data from mammals.
Directory of Open Access Journals (Sweden)
Nathan L Nehrt
2011-06-01
Full Text Available A common assumption in comparative genomics is that orthologous genes share greater functional similarity than do paralogous genes (the "ortholog conjecture". Many methods used to computationally predict protein function are based on this assumption, even though it is largely untested. Here we present the first large-scale test of the ortholog conjecture using comparative functional genomic data from human and mouse. We use the experimentally derived functions of more than 8,900 genes, as well as an independent microarray dataset, to directly assess our ability to predict function using both orthologs and paralogs. Both datasets show that paralogs are often a much better predictor of function than are orthologs, even at lower sequence identities. Among paralogs, those found within the same species are consistently more functionally similar than those found in a different species. We also find that paralogous pairs residing on the same chromosome are more functionally similar than those on different chromosomes, perhaps due to higher levels of interlocus gene conversion between these pairs. In addition to offering implications for the computational prediction of protein function, our results shed light on the relationship between sequence divergence and functional divergence. We conclude that the most important factor in the evolution of function is not amino acid sequence, but rather the cellular context in which proteins act.
Broken bridges: A counter-example of the ER=EPR conjecture
Chen, Pisin; Yeom, Dong-han
2016-01-01
In this paper, we provide a counter-example to the ER=EPR conjecture. In an anti-de Sitter space, we construct a pair of maximally entangled but separated black holes. Due to the vacuum decay of the anti-de Sitter background toward a deeper vacuum, these two parts can be trapped by bubbles. If these bubbles are reasonably large, then within the scrambling time, there should appear an Einstein-Rosen bridge between the two black holes. Now by tracing more details on the bubble dynamics, one can identify parameters such that one of the two bubbles either monotonically shrinks or expands. Because of the change of vacuum energy, one side of the black hole would evaporate completely. Due to the shrinking of the apparent horizon, a signal of one side of the Einstein-Rosen bridge can be viewed from the opposite side. We analytically and numerically demonstrate that within a reasonable semi-classical parameter regime, such process can happen. Therefore, the ER=EPR conjecture cannot be generic in its present form and i...
On the General Erdős-Turán Conjecture
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Georges Grekos
2014-01-01
Full Text Available The general Erdős-Turán conjecture states that if A is an infinite, strictly increasing sequence of natural numbers whose general term satisfies an≤cn2, for some constant c>0 and for all n, then the number of representations functions of A is unbounded. Here, we introduce the function ψ(n, giving the minimum of the maximal number of representations of a finite sequence A={ak:1≤k≤n} of n natural numbers satisfying ak≤k2 for all k. We show that ψ(n is an increasing function of n and that the general Erdős-Turán conjecture is equivalent to limn→∞ψ(n=∞. We also compute some values of ψ(n. We further introduce and study the notion of capacity, which is related to the ψ function by the fact that limn→∞ψ(n is the capacity of the set of squares of positive integers, but which is also of intrinsic interest.
Saari's homographic conjecture for planar equal-mass three-body problem in Newton gravity
Fujiwara, Toshiaki; Ozaki, Hiroshi; Taniguchi, Tetsuya
2012-01-01
Saari's homographic conjecture in N-body problem under the Newton gravity is the following; configurational measure \\mu=\\sqrt{I}U, which is the product of square root of the moment of inertia I=(\\sum m_k)^{-1}\\sum m_i m_j r_{ij}^2 and the potential function U=\\sum m_i m_j/r_{ij}, is constant if and only if the motion is homographic. Where m_k represents mass of body k and r_{ij} represents distance between bodies i and j. We prove this conjecture for planar equal-mass three-body problem. In this work, we use three sets of shape variables. In the first step, we use \\zeta=3q_3/(2(q_2-q_1)) where q_k \\in \\mathbb{C} represents position of body k. Using r_1=r_{23}/r_{12} and r_2=r_{31}/r_{12} in intermediate step, we finally use \\mu itself and \\rho=I^{3/2}/(r_{12}r_{23}r_{31}). The shape variables \\mu and \\rho make our proof simple.
Institute of Scientific and Technical Information of China (English)
周正柱
2011-01-01
基于对上海生物医药研发企业和软件开发研发外包的深度访谈及调研,分析了研发外包的内部动因;运用多元回归方法,分析了研发外包的外部环境动因.结果表明,研发外包内部动因主要表现在降低成本、获得专业化服务、提高产品质量等方面;外部环境因素主要有技术、经济、市场、政府和国际组织的态度与相关政策.%This article mainly empirically studies about the internal motivations of R&D outsourcing based on questionnaire surveys and interviews of R&D outsourcing of Shanghai science and technology enterprises, such as biomedical research and development and software development. And on the basis of multiple regressions, it analyses external motives of R&D outsourcing. The results show that there are internal motivations of reducing costs, getting specialized services, and so on. There are mainly technical, economic and market incentives about environmental factors. This helps to provide theoretical guidance for how to further outsourcing their R&D activities of our science and technology enterprises and for how to further improve service quality of our R&.D outsourcing service providers.
2016-10-01
Strength in the Storm: Transform Stress , Live in Balance, and Find Peace of Mind (book) 3. Relaxation and joyfulness techniques (P2) -Primary care...Video #1 (Fallujah) • Resting vitals: – BP: 136/85 (slightly stressed from driving tank) – RR: 14 breaths per min – Pulse: 85 BPM • Activated : – BP...Post-Traumatic Stress and Motivational Interviewing PRINCIPAL INVESTIGATOR: Karen H. Seal, MD MPH ORGANIZATION AND ADDRESS: Northern California
Wright, Noeline
2015-01-01
In New Zealand schools, the adoption and persistent use of digital tools to aid learning is a growing but uneven, trend, often linked to the practices of early adopters and/or robust wifi infrastructure. The Technology Adoption Model is used internationally to gauge levels of uptake of technological tools, particularly in commerce and also in…