Physics Abstracts CLASSIFICATION and CONTENTS (PACC)
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Probability and Statistics, Parastatistics, Boson, Fermion, Parafermion, Hausdorff Dimension, Percolation, Clusters
Applied Mathematics 2018, 8(1): 5-8 DOI: 10.5923/j.am.20180801.02 Why Fermions and Bosons are Observable as Single Particles while Quarks are not? Sencer Taneri Private Researcher, Turkey Abstract Bosons and Fermions are observable in nature while Quarks appear only in triplets for matter particles. We find a theoretical proof for this statement in this paper by investigating 2-dim model. The occupation numbers q are calculated by a power law dependence of occupation probability and utilizing Hausdorff dimension for the infinitely small mesh in the phase space. The occupation number for Quarks are manipulated and found to be equal to approximately three as they are Parafermions. Keywords Probability and Statistics, Parastatistics, Boson, Fermion, Parafermion, Hausdorff dimension, Percolation, Clusters There may be particles that obey some kind of statistics, 1. Introduction generally called parastatistics. The Parastatistics proposed in 1952 by H. Green was deduced using a quantum field The essential difference in classical and quantum theory (QFT) [2, 3]. Whenever we discover a new particle, descriptions of N identical particles is in their individuality, it is almost certain that we attribute its behavior to the rather than in their indistinguishability [1]. Spin of the property that it obeys some form of parastatistics and the particle is one of its intrinsic physical quantity that is unique maximum occupation number q of a given quantum state to its individuality. The basis for how the quantum states for would be a finite number that could assume any integer N identical particles will be occupied may be taken as value as 1<q <∞ (see Table 1). -
Stars and Telescopes : a Resource Book for Teachers of Lower School Science
Edith Cowan University Research Online ECU Publications Pre. 2011 1981 Stars and telescopes : a resource book for teachers of lower school science Clifton L. Smith Follow this and additional works at: https://ro.ecu.edu.au/ecuworks Part of the Science and Mathematics Education Commons Smith, C. (1981). Stars and telescopes : a resource book for teachers of lower school science. Nedlands, Australia: Nedlands College of Advanced Education. This Book is posted at Research Online. https://ro.ecu.edu.au/ecuworks/7034 Edith Cowan University Copyright Warning You may print or download ONE copy of this document for the purpose of your own research or study. The University does not authorize you to copy, communicate or otherwise make available electronically to any other person any copyright material contained on this site. You are reminded of the following: Copyright owners are entitled to take legal action against persons who infringe their copyright. A reproduction of material that is protected by copyright may be a copyright infringement. Where the reproduction of such material is done without attribution of authorship, with false attribution of authorship or the authorship is treated in a derogatory manner, this may be a breach of the author’s moral rights contained in Part IX of the Copyright Act 1968 (Cth). Courts have the power to impose a wide range of civil and criminal sanctions for infringement of copyright, infringement of moral rights and other offences under the Copyright Act 1968 (Cth). Higher penalties may apply, and higher damages may be awarded, for offences and infringements involving the conversion of material into digital or electronic form. -
The Conventionality of Parastatistics
The Conventionality of Parastatistics David John Baker Hans Halvorson Noel Swanson∗ March 6, 2014 Abstract Nature seems to be such that we can describe it accurately with quantum theories of bosons and fermions alone, without resort to parastatistics. This has been seen as a deep mystery: paraparticles make perfect physical sense, so why don't we see them in nature? We consider one potential answer: every paraparticle theory is physically equivalent to some theory of bosons or fermions, making the absence of paraparticles in our theories a matter of convention rather than a mysterious empirical discovery. We argue that this equivalence thesis holds in all physically admissible quantum field theories falling under the domain of the rigorous Doplicher-Haag-Roberts approach to superselection rules. Inadmissible parastatistical theories are ruled out by a locality- inspired principle we call Charge Recombination. Contents 1 Introduction 2 2 Paraparticles in Quantum Theory 6 ∗This work is fully collaborative. Authors are listed in alphabetical order. 1 3 Theoretical Equivalence 11 3.1 Field systems in AQFT . 13 3.2 Equivalence of field systems . 17 4 A Brief History of the Equivalence Thesis 20 4.1 The Green Decomposition . 20 4.2 Klein Transformations . 21 4.3 The Argument of Dr¨uhl,Haag, and Roberts . 24 4.4 The Doplicher-Roberts Reconstruction Theorem . 26 5 Sharpening the Thesis 29 6 Discussion 36 6.1 Interpretations of QM . 44 6.2 Structuralism and Haecceities . 46 6.3 Paraquark Theories . 48 1 Introduction Our most fundamental theories of matter provide a highly accurate description of subatomic particles and their behavior. -
Stars and Their Spectra: an Introduction to the Spectral Sequence Second Edition James B
Cambridge University Press 978-0-521-89954-3 - Stars and Their Spectra: An Introduction to the Spectral Sequence Second Edition James B. Kaler Index More information Star index Stars are arranged by the Latin genitive of their constellation of residence, with other star names interspersed alphabetically. Within a constellation, Bayer Greek letters are given first, followed by Roman letters, Flamsteed numbers, variable stars arranged in traditional order (see Section 1.11), and then other names that take on genitive form. Stellar spectra are indicated by an asterisk. The best-known proper names have priority over their Greek-letter names. Spectra of the Sun and of nebulae are included as well. Abell 21 nucleus, see a Aurigae, see Capella Abell 78 nucleus, 327* ε Aurigae, 178, 186 Achernar, 9, 243, 264, 274 z Aurigae, 177, 186 Acrux, see Alpha Crucis Z Aurigae, 186, 269* Adhara, see Epsilon Canis Majoris AB Aurigae, 255 Albireo, 26 Alcor, 26, 177, 241, 243, 272* Barnard’s Star, 129–130, 131 Aldebaran, 9, 27, 80*, 163, 165 Betelgeuse, 2, 9, 16, 18, 20, 73, 74*, 79, Algol, 20, 26, 176–177, 271*, 333, 366 80*, 88, 104–105, 106*, 110*, 113, Altair, 9, 236, 241, 250 115, 118, 122, 187, 216, 264 a Andromedae, 273, 273* image of, 114 b Andromedae, 164 BDþ284211, 285* g Andromedae, 26 Bl 253* u Andromedae A, 218* a Boo¨tis, see Arcturus u Andromedae B, 109* g Boo¨tis, 243 Z Andromedae, 337 Z Boo¨tis, 185 Antares, 10, 73, 104–105, 113, 115, 118, l Boo¨tis, 254, 280, 314 122, 174* s Boo¨tis, 218* 53 Aquarii A, 195 53 Aquarii B, 195 T Camelopardalis, -
A Scientific Metaphysical Naturalisation of Information
1 A Scientific Metaphysical Naturalisation of Information With a indication-based semantic theory of information and an informationist statement of physicalism. Bruce Long A thesis submitted to fulfil requirements for the degree of Doctor of Philosophy Faculty of Arts and Social Sciences The University of Sydney February 2018 2 Abstract The objective of this thesis is to present a naturalised metaphysics of information, or to naturalise information, by way of deploying a scientific metaphysics according to which contingency is privileged and a-priori conceptual analysis is excluded (or at least greatly diminished) in favour of contingent and defeasible metaphysics. The ontology of information is established according to the premises and mandate of the scientific metaphysics by inference to the best explanation, and in accordance with the idea that the primacy of physics constraint accommodates defeasibility of theorising in physics. This metaphysical approach is used to establish a field ontology as a basis for an informational structural realism. This is in turn, in combination with information theory and specifically mathematical and algorithmic theories of information, becomes the foundation of what will be called a source ontology, according to which the world is the totality of information sources. Information sources are to be understood as causally induced configurations of structure that are, or else reduce to and/or supervene upon, bounded (including distributed and non-contiguous) regions of the heterogeneous quantum field (all quantum fields combined) and fluctuating vacuum, all in accordance with the above-mentioned quantum field-ontic informational structural realism (FOSIR.) Arguments are presented for realism, physicalism, and reductionism about information on the basis of the stated contingent scientific metaphysics. -
The Connection Between Spin and Statistics
Sudarshan: Seven Science Quests IOP Publishing Journal of Physics: Conference Series 196 (2009) 012011 doi:10.1088/1742-6596/196/1/012011 The connection between spin and statistics Luis J. Boya Departamento de Física Teórica, Universidad de Zaragoza E - 50 009, Zaragoza, Spain E-Mail: [email protected] Abstract. After some brief historical remarks we recall the first demonstration of the Spin-Statistics theorem by Pauli, and some further developments, like Streater- Wightman’s, in the axiomatic considerations. Sudarshan’s short proof then follows by considering only the time part of the kinetic term in the lagrangian: the identity SU(2)=Sp(1,C) is crucial for the argument. Possible generalization to arbitrary dimensions are explored, and seen to depend crucially on the type of spinors, obeying Bott´s periodicity 8. In particular, it turns out that for space dimentions (7, 8, or 9) modulo 8, the conventional result does not automatically hold: there can be no Fermions in these dimensions. 1. Introduction The idea of this work came from discussions with Sudarshan in Zaragoza some years ago. George was surprised to learn that the properties of spinors crucial for the ordinary connection between spin and statistics would not hold in arbitrary dimensions, because of periodicity 8 of real Clifford algebras. After many discussions and turnarounds, I am happy today to present this collaboration, and I also apologize for the delay, for which I am mainly responsible. In any case, the priviledge to work and discuss physics with Sudarshan is a unique experience, for which I have been most fortunate. -
Summer Solstice 1985 No
Summer Solstice 1985 No. 47 • a· .;.. \ .. .~ ' ... ...... e"., 5 Q."" « o in en tI( u • • " '·,!_M! H. BATTErJ Di-l~ ~ I ;.J I Of..! (.. 51 R Of HV SIC ~ L. em S;:::P VA TOR v 5071 WEST SAANI~H ROAD \:I..:~·rC,F~Irit Be \.. <,:1.<. c, !'16 • Cassiopeia Editorial The recent Annual General Meeting celebrated the fiftieth anniversary of the founding of the DOD, and in the process demonstrated that one of the many accomplishments of the University of Toronto 's Astronomy Department is skill in planning and organizing a meeting. No. 47 Summer Solstice 1985 Despite extra complications such as the joint session with the Planetarium Association of Canada on education in astronomy, and the ceremony at the DOD, everything seemed to go extremely smoothly. Highlights of the meeting were the first annual Helen Sawyer Hogg Public Lecture, given by Owen Gingerich and entitled "The Mysterious Nebulae: 1610-1924", the R.M. Petrie Memorial Lecture on "The Galactic CANADIAN ASTRONOMICAL SOCIETY Centre" by Charles Townes, and two very stimulating invited talks, on "Physical Processes in White Dwarfs" by Gilles Gontaine, and on "The SOCIETE CANADIENNE D'ASTRONOMIE Ages of Gl obul ar Cl usters from Ste 11 ar Model s" by Don VandenBerg . A special session on the 000 produced some very entertaining reminiscenses from Peter Millman, Bill Harris, Chris Purton and Don MacRae . Editor: Colin Se arfe, University of Victoria One of the few failings of the meeti ngs was the inadequate space allotted for the poster sessions. The boards themselves were spacious and their size was well publicized in advance. -
Curriculum Vitae
DAVID JOHN BAKER CURRICULUM VITAE Department of Philosophy [email protected] 2215 Angell Hall http://www-personal.umich.edu/~djbaker 435 S State St. Ann Arbor, MI 48109-1003 APPOINTMENTS Associate Professor of Philosophy, University of Michigan, 2014-present. Assistant Professor of Philosophy, University of Michigan, 2008-2014. EDUCATION PhD. in Philosophy, Princeton University, September 2008. Advisor: Hans Halvorson. B.S. in Philosophy (with Highest Honors) and Physics, University of Michigan, April 2003. AREAS OF SPECIALIZATION Philosophy of Physics, Philosophy of Science, Metaphysics. AREAS OF COMPETENCE Moral Philosophy, Logic, Philosophy of Religion, Epistemology. PUBLICATIONS “Does String Theory Posit Extended Simples?” Philosophers’ Imprint 16 (2016): Issue 18. “The Philosophy of Quantum Field Theory.” Oxford Handbooks Online (2016): DOI 10.1093/oxfordhb/9780199935314.013.33 “The Conventionality of Parastatistics,” with Hans Halvorson and Noel Swanson. The British Journal for the Philosophy of Science 66 (2015): 929-976. “How is spontaneous symmetry breaking possible? Understanding Wigner’s theorem in light of unitary inequivalence,” with Hans Halvorson. Studies in History and Philosophy of Modern Physics 44 (2013): 464-469. “Identity, Superselection Theory and the Statistical Properties of Quantum Fields.” Philosophy of Science 80 (2013): 262-285. “‘The Experience of Left and Right’ Meets the Physics of Left and Right.” Nous 46 (2012): 483-498. “Broken Symmetry and Spacetime.” Philosophy of Science 78 (2011): 128-148. “Symmetry and the Metaphysics of Physics.” Philosophy Compass 5 (2010): 1157-1166. “Antimatter,” with Hans Halvorson. The British Journal for the Philosophy of Science 61 (2010): 93-121. DAVID JOHN BAKER – CURRICULUM VITAE 2 “Against Field Interpretations of Quantum Field Theory.” The British Journal for the Philosophy of Science 60 (2009): 585-609. -
Arxiv:0805.0285V1
Generalizations of Quantum Statistics O.W. Greenberg1 Center for Fundamental Physics Department of Physics University of Maryland College Park, MD 20742-4111, USA, Abstract We review generalizations of quantum statistics, including parabose, parafermi, and quon statistics, but not including anyon statistics, which is special to two dimensions. The general principles of quantum theory allow statistics more general than bosons or fermions. (Bose statistics and Fermi statistics are discussed in separate articles.) The restriction to Bosons or Fermions requires the symmetrization postu- late, “the states of a system containing N identical particles are necessarily either all symmetric or all antisymmetric under permutations of the N particles,” or, equiv- alently, “all states of identical particles are in one-dimensional representations of the symmetric group [1].” A.M.L. Messiah and O.W. Greenberg discussed quantum mechanics without the symmetrization postulate [2]. The spin-statistics connec- arXiv:0805.0285v1 [quant-ph] 2 May 2008 tion, that integer spin particles are bosons and odd-half-integer spin particles are fermions [3], is an independent statement. Identical particles in 2 space dimensions are a special case, “anyons.” (Anyons are discussed in a separate article.) Braid group statistics, a nonabelian analog of anyons, are also special to 2 space dimensions All observables must be symmetric in the dynamical variables associated with identical particles. Observables can not change the permutation symmetry type of the wave function; i.e. there is a superselection rule separating states in inequivalent representations of the symmetric group and when identical particles can occur in states that violate the spin-statistics connection their transitions must occur in the same representation of the symmetric group. -
${\Mathbb Z} 2\Times {\Mathbb Z} 2 $-Graded Parastatistics In
Z2 ˆ Z2-graded parastatistics in multiparticle quantum Hamiltonians Francesco Toppan∗ August 27, 2020 CBPF, Rua Dr. Xavier Sigaud 150, Urca, cep 22290-180, Rio de Janeiro (RJ), Brazil. Abstract The recent surge of interest in Z2 Z2-graded invariant mechanics poses the challenge of ˆ understanding the physical consequences of a Z2 Z2-graded symmetry. In this paper it is shown that non-trivial physicsˆ can be detected in the multiparticle sector of a theory, being induced by the Z2 Z2-graded parastatistics obeyed by the particles. ˆ The toy model of the N 4 supersymmetric/ Z2 Z2-graded oscillator is used. In this set-up the one-particle energy“ levels and their degenerationsˆ are the same for both supersymmetric and Z2 Z2-graded versions. Nevertheless, in the multiparticle sector, a measurement of an observableˆ operator on suitable states can discriminate whether the system under consideration is composed by ordinary bosons/fermions or by Z2 Z2-graded ˆ particles. Therefore, Z2 Z2-graded mechanics has experimentally testable consequences. ˆ Furthermore, the Z2 Z2-grading constrains the observables to obey a superselection rule. ˆ As a technical tool, the multiparticle sector is encoded in the coproduct of a Hopf algebra defined on a Universal Enveloping Algebra of a graded Lie superalgebra with a braided tensor product. arXiv:2008.11554v1 [hep-th] 26 Aug 2020 CBPF-NF-007/20 ∗E-mail: [email protected] 1 1 Introduction This paper presents a theoretical test of the physical consequences of the Z2 Z2-graded paras- ˆ tatistics in a toy model case of a quantum Hamiltonian. -
A Multi-Technique Study of the Dynamical Evolution of the Viscous Disk Around the Be Star Ω Cma
University of São Paulo (USP) Institute of Astronomy, Geophysics and Atmospheric Sciences Department of Astronomy Sayyed Mohammad Reza Ghoreyshi A Multi-technique Study of the Dynamical Evolution of the Viscous Disk around the Be Star w CMa São Paulo 2018 Sayyed Mohammad Reza Ghoreyshi A Multi-technique Study of the Dynamical Evolution of the Viscous Disk around the Be Star w CMa Tese apresentada ao Departamento de Astrono- mia do Instituto de Astronomia, Geofísica e Ci- ências Atmosféricas da Universidade de São Paulo como requisito parcial para a obtenção do título de Doutor em Ciências. Área de Concentração: Astronomia Orientador: Prof. Dr. Alex Cavaliéri Carciofi São Paulo 2018 To my dear wife, Minoo, who tolerated all difficulties, and to my dear kids, Arshida & Arshavir, who endured a difficult time, for this thesis becoming true. Acknowledgements I would like to thank my supervisor, Prof. Dr. Alex Cavaliéri Carciofi, for the patient guidance, encouragement and advice he has provided throughout my time as his student. I have been extremely lucky to have a supervisor who cared so much about my work, and who responded to my questions and queries so promptly. I would also like to thank every body at IAG who helped me scientifically or technically. In particular I would like to thank Dr. Daniel Moser Faes for his constant helps at different points of this thesis. It would have been very difficult for me to take this work to completion without his incredible support and advice. I must express my sincere gratitude to Minoo, my wife, for her continued support, encoura- gement and patience for experiencing all of the ups and downs of my research time. -
The Electric Sun Hypothesis
Basics of astrophysics revisited. II. Mass- luminosity- rotation relation for F, A, B, O and WR class stars Edgars Alksnis [email protected] Small volume statistics show, that luminosity of bright stars is proportional to their angular momentums of rotation when certain relation between stellar mass and stellar rotation speed is reached. Cause should be outside of standard stellar model. Concept allows strengthen hypotheses of 1) fast rotation of Wolf-Rayet stars and 2) low mass central black hole of the Milky Way. Keywords: mass-luminosity relation, stellar rotation, Wolf-Rayet stars, stellar angular momentum, Sagittarius A* mass, Sagittarius A* luminosity. In previous work (Alksnis, 2017) we have shown, that in slow rotating stars stellar luminosity is proportional to spin angular momentum of the star. This allows us to see, that there in fact are no stars outside of “main sequence” within stellar classes G, K and M. METHOD We have analyzed possible connection between stellar luminosity and stellar angular momentum in samples of most known F, A, B, O and WR class stars (tables 1-5). Stellar equatorial rotation speed (vsini) was used as main parameter of stellar rotation when possible. Several diverse data for one star were averaged. Zero stellar rotation speed was considered as an error and corresponding star has been not included in sample. RESULTS 2 F class star Relative Relative Luminosity, Relative M*R *eq mass, M radius, L rotation, L R eq HATP-6 1.29 1.46 3.55 2.950 2.28 α UMi B 1.39 1.38 3.90 38.573 26.18 Alpha Fornacis 1.33