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Quantum Mechanics in symmetry language  [PDF]
Houri Ziaeepour
Physics , 2013,
Abstract: We consider symmetry as a foundational concept in quantum mechanics and rewrite quantum mechanics and measurement axioms in this description. We argue that issues related to measurements and physical reality of states can be better understood in this view. In particular, the abstract concept of symmetry provides a basis-independent definition for observables. Moreover, we show that the apparent projection/collapse of the state as the final step of measurement or decoherence is the result of breaking of symmetries. This phenomenon is comparable with a phase transition by spontaneous symmetry breaking, and makes the process of decoherence and classicality a natural fate of complex systems consisting of many interacting subsystems. Additionally, we demonstrate that the property of state space as a vector space representing symmetries is more fundamental than being an abstract Hilbert space, and its $L2$ integrability can be obtained from the imposed condition of being a representation of a symmetry group and general properties of probability distributions.
Quantum Mechanics and the Philosophy of Language:Reconsideration of Traditional Philosophies  [PDF]
Shiro Ishikawa
Journal of Quantum Information Science (JQIS) , 2012, DOI: 10.4236/jqis.2012.21002
Abstract: Recently we proposed “a new interpretation of quantum mechanics (called quantum and classical measurement theory)” in this journal (JQIS: Vol. 1, No. 2), which was characterized as the metaphysical and linguistic turn of quantum mechanics. This turn from physics to language does not only realize the remarkable extension of quantum mechanics but also yield the quantum mechanical world view (i.e., the philosophy of quantum mechanics). And thus, the turn urges us to dream that traditional philosophies (i.e., Parmenides, Plato, Aristotle, Descartes, John Locke, Berkeley, Hume, Kant, Saussure, Wittgenstein, etc.) can be understood in the quantum mechanical world view. This dream will be challenged in this paper. We, of course, know that most scientists are skeptical to philosophy. Still, we can expect that readers find a good linguistic philosophy (i.e. philosophy of language) in quantum mechanics.
Comment on "An Arrow of Time Operator for Standard Quantum Mechanics" - a sign of the time!  [PDF]
Michael J. W. Hall
Physics , 2008,
Abstract: It is shown that the `arrow of time' operator, M_F, recently suggested by Strauss et al., in arXiv:0802.2448v1 [quant-ph], is simply related to the sign of the canonical `time' observable, T (apparently first introduced by Holevo). In particular, the monotonic decrease of < M_F > corresponds to the fact that < sgn T > increases monotonically with time. This relationship also provides a physical interpretation of the property M_F < 1. Some further properties and possible generalisations are pointed out, including to almost-periodic systems.
From Classical to Quantum Mechanics: "How to translate physical ideas into mathematical language"  [PDF]
H. Bergeron
Physics , 2001, DOI: 10.1063/1.1386410
Abstract: In this paper, we investigate the connection between Classical and Quantum Mechanics by dividing Quantum Theory in two parts: - General Quantum Axiomatics (a system is described by a state in a Hilbert space, observables are self-adjoint operators and so on) - Quantum Mechanics properly that specifies the Hilbert space, the Heisenberg rule, the free Hamiltonian... We show that General Quantum Axiomatics (up to a supplementary "axiom of classicity") can be used as a non-standard mathematical ground to formulate all the ideas and equations of ordinary Classical Statistical Mechanics. So the question of a "true quantization" with "h" must be seen as an independent problem not directly related with quantum formalism. Moreover, this non-standard formulation of Classical Mechanics exhibits a new kind of operation with no classical counterpart: this operation is related to the "quantization process", and we show why quantization physically depends on group theory (Galileo group). This analytical procedure of quantization replaces the "correspondence principle" (or canonical quantization) and allows to map Classical Mechanics into Quantum Mechanics, giving all operators of Quantum Mechanics and Schrodinger equation. Moreover spins for particles are naturally generated, including an approximation of their interaction with magnetic fields. We find also that this approach gives a natural semi-classical formalism: some exact quantum results are obtained only using classical-like formula. So this procedure has the nice property of enlightening in a more comprehensible way both logical and analytical connection between classical and quantum pictures.
Cognitive Semiotics Approach for Communication Development of Language Learners
T. Uvaraj,Mumtaz Begum,Gopi @ Pavadai. K
Theory and Practice in Language Studies , 2011, DOI: 10.4304/tpls.1.10.1420-1423
Abstract: Communication is a two way mode of expression between the encoder and the decoder. The role of communication in the human society is sharing the affective and cognitive attributes to interact. Many times communicated message failed to understand or process by the receiver. Researches proved that lack of skills in communication results to false understanding. The language has four communication skills (Listening, Speaking, Reading and Writing) where the representations are in the forms of signs and symbols. The task of the language teacher is making the learner to construct meaningful semantic and syntactic representations by signs and symbols to enhance the communication competencies. The lack of thematic, vocabulary and grammatical structures insists the language learners to struggle in expressing their thinking in written and spoken form. Thinking depends on the cognition activities, i.e., Representation and Computation. Cognitive is an interdisciplinary study of the mental phenomena involving human mind in terms of perception, memory and language. Semiotics is the study of signs or symbols and Cognitive semiotics studies the relations between signs and language. This paper explores the role of cognition and semiotics in developing better and effective communication in spoken and written forms of Language learners by the Language teachers.
Bohmian mechanics contradicts quantum mechanics  [PDF]
Arnold Neumaier
Physics , 2000,
Abstract: It is shown that, for a harmonic oscillator in the ground state, Bohmian mechanics and quantum mechanics predict values of opposite sign for certain time correlations. The discrepancy can be explained by the fact that Bohmian mechanics has no natural way to accomodate the Heisenberg picture, since the local expectation values that define the beables of the theory depend on the Heisenberg time being used to define the operators. Relations to measurement are discussed, too, and shown to leave no loophole for claiming that Bohmian mechanics reproduces all predictions of quantum mechanics exactly.
Quantum Mechanics in Phase Space  [PDF]
Ali Mohammad Nassimi
Physics , 2007,
Abstract: The basics of the Wigner formulation of Quantum-Mechanics and few related interpretational issues are presented in a simple language. This formulation has extensive applications in Quantum Optics and in Mixed Quantum-Classical formulations.
The semiotics of advertisements: “Reading advertisements as a sign systems”
U?ur Bat?
International Journal of Human Sciences , 2007,
Abstract: This article, making use of the perspectives of semiology, attempts to provide a way to analyze how meaning is arranged and used in advertising texts. In this paper, linguistics is taken as a model of main narrative style in the semiological perspective and linguistics principles are applied to examine not only the language but also the advertising textual. Following this path, semiological analysis has been realized on two sample advertising texts which are chosen among the cosmetic advertisements with the aim of looking at how advertising is realized as a system of signs, and seeing the deep meaning of advertising in relation with market conditions. While conducting the research, the theories of Arthur Asa Berger, Roland Barthes and David Chandler has been applied to. At the advertisements which are research material, products which have no meaning or have a different meaning at the begining, have gained various meanings by replacing object or person which is meaningful for us in the signification structure of advertising.
Sign Language Tutoring Tool  [PDF]
Oya Aran,Ismail Ari,Alexandre Benoit,Ana Huerta Carrillo,Fran?ois-Xavier Fanard,Pavel Campr,Lale Akarun,Alice Caplier,Michele Rombaut,Bulent Sankur
Computer Science , 2008,
Abstract: In this project, we have developed a sign language tutor that lets users learn isolated signs by watching recorded videos and by trying the same signs. The system records the user's video and analyses it. If the sign is recognized, both verbal and animated feedback is given to the user. The system is able to recognize complex signs that involve both hand gestures and head movements and expressions. Our performance tests yield a 99% recognition rate on signs involving only manual gestures and 85% recognition rate on signs that involve both manual and non manual components, such as head movement and facial expressions.
PT symmetry in relativistic quantum mechanics  [PDF]
Carl M. Bender,Philip D. Mannheim
Physics , 2011, DOI: 10.1103/PhysRevD.84.105038
Abstract: In nonrelativistic quantum mechanics and in relativistic quantum field theory, time t is a parameter and thus the time-reversal operator T does not actually reverse the sign of t. However, in relativistic quantum mechanics the time coordinate t and the space coordinates x are treated on an equal footing and all are operators. In this paper it is shown how to extend PT symmetry from nonrelativistic to relativistic quantum mechanics by implementing time reversal as an operation that changes the sign of the time coordinate operator t. Some illustrative relativistic quantum-mechanical models are constructed whose associated Hamiltonians are non-Hermitian but PT symmetric, and it is shown that for each such Hamiltonian the energy eigenvalues are all real.
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