Results for ' matrix mechanics'

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  1.  72
    Why were Matrix Mechanics and Wave Mechanics considered equivalent?Slobodan Perovic - 2008 - Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics 39 (2):444-461.
    A recent rethinking of the early history of Quantum Mechanics deemed the late 1920s agreement on the equivalence of Matrix Mechanics and Wave Mechanics, prompted by Schrödinger's 1926 proof, a myth. Schrödinger supposedly failed to prove isomorphism, or even a weaker equivalence (“Schrödinger-equivalence”) of the mathematical structures of the two theories; developments in the early 1930s, especially the work of mathematician von Neumann provided sound proof of mathematical equivalence. The alleged agreement about the Copenhagen Interpretation, predicated (...)
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  2.  88
    Why were two theories (matrix mechanics and wave mechanics) deemed logically distinct, and yet equivalent, in quantum mechanics?Slobodan Perovic - 2007 - In Christopher Lehrer (ed.), First Annual Conference in the Foundations and History of Quantum Physics. Max Planck Institute for History of Science.
    A recent rethinking of the early history of Quantum Mechanics deemed the late 1920s agreement on the equivalence of Matrix Mechanics and Wave Mechanics, prompted by Schrödinger’s 1926 proof, a myth. Schrödinger supposedly failed to achieve the goal of proving isomorphism of the mathematical structures of the two theories, while only later developments in the early 1930s, especially the work of mathematician John von Neumman (1932) provided sound proof of equivalence. The alleged agreement about the Copenhagen (...)
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  3. Van vleck and Slater: Two americans on the road to matrix mechanics.Michel Janssen - unknown
    I relate the story of how matrix mechanics grew out of the treatment of optical dispersion in the old quantum theory, paying special attention to the contributions of the American theoretical physicists John H. Van Vleck and John C. Slater. Van Vleck shares the credit with Max Born for being the first to publish a full derivation of the crucial Kramers dispersion formula using Bohr’s correspondence principle. Slater was one of the architects of the short-lived but influential Bohr-Kramers-Slater (...)
     
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  4.  73
    Translation as heuristics: Heisenberg׳s turn to matrix mechanics.Alexander Blum, Martin Jähnert, Christoph Lehner & Jürgen Renn - 2017 - Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics 60:3-22.
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  5.  44
    Jagdish Mehra & Helmut Rechenberg. The Historical Development of Quantum Theory. Volume 1, The Quantum Theory of Planck, Einstein, Bohr and Sommerfeld: Its Foundations and the Rise of its Difficulties 1900–1925. Volume 2, The Discovery of the Quantum Mechanics 1925. Volume 3, The Formulation of Matrix Mechanics and its Modifications 1925–1926. Volume 4, The Fundamental Equations of Quantum Mechanics 1925–1926 and The Reception of the New Quantum Mechanics 1925–1926. New York, Heidelberg and Berlin: Springer-Verlag, 1982. Volume 1 in two parts, pp. xlvii + 372, vi + 506. ISBN 3-540-90642-8, 3-540-90667-3. DM 75, DM 85. Volume 2, pp. vii + 355. ISBN 3-540-90674-6. DM 65. Volume 3, pp. vii + 334. ISBN 3-540-90675-4. DM 75. Volume 4, pp. viii + 322. ISBN 3-540-90680-0. DM 75. - Andrew Pickering. Constructing Quarks. A Sociological History of Particle Physics. Edinburgh: Edinburgh University Press, 1984. Pp. xi + 468. ISBN 0-85224-458-4 £20. [REVIEW]John Hendry - 1986 - British Journal for the History of Science 19 (2):206-208.
  6. Density Matrix in Quantum Mechanics and Distinctness of Ensembles Having the Same Compressed Density Matrix.Gui Lu Long, Yi-Fan Zhou, Jia-Qi Jin, Yang Sun & Hai-Woong Lee - 2006 - Foundations of Physics 36 (8):1217-1243.
    We clarify different definitions of the density matrix by proposing the use of different names, the full density matrix for a single-closed quantum system, the compressed density matrix for the averaged single molecule state from an ensemble of molecules, and the reduced density matrix for a part of an entangled quantum system, respectively. We show that ensembles with the same compressed density matrix can be physically distinguished by observing fluctuations of various observables. This is in (...)
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  7.  23
    Matrix formulation of special relativity in classical mechanics and electromagnetic theory.Authur A. Frost - 1975 - Foundations of Physics 5 (4):619-641.
    The two-component spinor theory of van der Waerden is put into a convenient matrix notation. The mathematical relations among various types of matrices and the rule for forming covariant expressions are developed. Relativistic equations of classical mechanics and electricity and magnetism are expressed in this notation. In this formulation the distinction between time and space coordinates in the four-dimensional space-time continuum falls out naturally from the assumption that a four-vector is represented by a Hermitian matrix. The indefinite (...)
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  8.  13
    Reaction mechanisms between Al and Fe3O4powders in the formation of an Al-based metal matrix composite.K. C. Chung, F. L. Kwong, Jia Li & Dickon H. L. Ng - 2009 - Philosophical Magazine 89 (19):1535-1553.
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  9.  24
    Microstructure and mechanical properties of continuous Al2O3fibre reinforced Ni45Al45Cr7.5Ta2.5alloy matrix composites.Y. Zhong, D. Hajas, W. Hu, H. Chen & G. Gottstein - 2007 - Philosophical Magazine 87 (7):1019-1032.
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  10. Minds in the Matrix: Embodied Cognition and Virtual Reality (2nd edition).Paul Smart - 2014 - In Lawrence A. Shapiro (ed.), The Routledge Handbook of Embodied Cognition. New York: Routledge.
    The present chapter discusses the implications of virtual reality for the theory and practice of embodied cognitive science. The chapter discusses how recent technological innovations are poised to reshape our understanding of the materially-embodied and environmentally-situated mind, providing us with a new means of studying the mechanisms responsible for intelligent behavior. The chapter also discusses how a synthetically-oriented shift in our approach to embodied intelligence alters our view of familiar problems, most notably the distinction between embedded and extended cognition. The (...)
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  11.  4
    Bohmian Mechanics as a Practical Tool.Xabier Oianguren-Asua, Carlos F. Destefani, Matteo Villani, David K. Ferry & Xavier Oriols - 2024 - In Angelo Bassi, Sheldon Goldstein, Roderich Tumulka & Nino Zanghi (eds.), Physics and the Nature of Reality: Essays in Memory of Detlef Dürr. Springer. pp. 105-123.
    In this chapter, we will take a trip around several hot-spots where Bohmian mechanics and its capacity to describe the microscopic reality, even in the absence of measurements, can be harnessed as computational tools, in order to help in the prediction of phenomenologically accessible information (also useful for the followers of the Copenhagen theory). As a first example, we will see how a Stochastic Schrödinger Equation, when used to compute the reduced density matrix of a non-Markovian open quantum (...)
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  12.  25
    Matrix logic and mind: a probe into a unified theory of mind and matter.August Stern - 1992 - New York: Distributors for the U.S. and Canada, Elsevier Science Pub. Co..
    In this revolutionary work, the author sets the stage for the science of the 21st Century, pursuing an unprecedented synthesis of fields previously considered unrelated. Beginning with simple classical concepts, he ends with a complex multidisciplinary theory requiring a high level of abstraction. The work progresses across the sciences in several multidisciplinary directions: Mathematical logic, fundamental physics, computer science and the theory of intelligence. Extraordinarily enough, the author breaks new ground in all these fields. In the field of fundamental physics (...)
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  13.  75
    The code of terpsichore the dance theory of Carlo blasis: Mechanics as the matrix of grace.Gabriele Brandstettter - 2004 - Topoi 24 (1):67-79.
    The essay examines both the dances and the dance notation of renowned nineteenth century choreographer Carlo Blasis. It looks in detail at Blasis major treatise The Code of Terpsichore in an effort to evaluate how Blasis linked a science of movement to a conception of the body oriented around the prevailing aesthetics informing all of the fine arts. Identifying Blasis as both a philosopher and a mechanist, this essay analyzes his approach to teaching basic ballet vocabulary, and in particular the (...)
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  14. Quantum Mechanics in a Time-Asymmetric Universe: On the Nature of the Initial Quantum State.Eddy Keming Chen - 2021 - British Journal for the Philosophy of Science 72 (4):1155–1183.
    In a quantum universe with a strong arrow of time, we postulate a low-entropy boundary condition to account for the temporal asymmetry. In this paper, I show that the Past Hypothesis also contains enough information to simplify the quantum ontology and define a unique initial condition in such a world. First, I introduce Density Matrix Realism, the thesis that the quantum universe is described by a fundamental density matrix that represents something objective. This stands in sharp contrast to (...)
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  15.  10
    Factors affecting the microstructure and mechanical properties of Ti-Al3Ti core-shell-structured particle-reinforced Al matrix composites.Baisong Guo, Jianhong Yi, Song Ni, Rujuan Shen & Min Song - 2016 - Philosophical Magazine 96 (12):1197-1211.
  16.  78
    The Density Matrix in the de Broglie--Bohm Approach.O. J. E. Maroney - 2005 - Foundations of Physics 35 (3):493-510.
    If the density matrix is treated as an objective description of individual systems, it may become possible to attribute the same objective significance to statistical mechanical properties, such as entropy or temperature, as to properties such as mass or energy. It is shown that the de Broglie--Bohm interpretation of quantum theory can be consistently applied to density matrices as a description of individual systems. The resultant trajectories are examined for the case of the delayed choice interferometer, for which Bell (...)
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  17. The Wentaculus: Density Matrix Realism Meets the Arrow of Time.Eddy Keming Chen - manuscript
    Two of the most difficult problems in the foundations of physics are (1) what gives rise to the arrow of time and (2) what the ontology of quantum mechanics is. They are difficult because the fundamental dynamical laws of physics do not privilege an arrow of time, and the quantum-mechanical wave function describes a high-dimensional reality that is radically different from our ordinary experiences. -/- In this paper, I characterize and elaborate on the ``Wentaculus” theory, a new approach to (...)
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  18. The Ideological Matrix of Science: Natural Selection and Immunity as Case Studies.Agustin Ostachuk - 2019 - Cosmos and History: The Journal of Natural and Social Philosophy 15 (1):182-213.
    The modern concept of ideology was established by the liberal politician and philosopher Destutt de Tracy, with the objective of creating an all-embracing and general science of ideas, which followed the sensualist and empiricist trend initiated by Locke that culminated in the positivism of Comte. Natural selection and immunity are two key concepts in the history of biology that were strongly based on the Malthusian concept of struggle for existence. This concept wrongly assumed that population grew faster than the means (...)
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  19.  16
    Open Systems’ Density Matrix Properties in a Time Coarsened Formalism.Robert Englman & Asher Yahalom - 2015 - Foundations of Physics 45 (6):673-690.
    The concept of time-coarsened density matrix for open systems has frequently featured in equilibrium and non-equilibrium statistical mechanics, without being probed as to the detailed consequences of the time averaging procedure. In this work we introduce and prove the need for a selective and non-uniform time-sampling, whose form depends on the properties of the bath. It is also applicable when an open microscopic sub-system is coupled to another finite system. By use of a time-periodic minimal coupling model between (...)
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  20.  14
    Insider trading: Extracellular matrix proteins and their non‐canonical intracellular roles.Andrew L. Hellewell & Josephine C. Adams - 2016 - Bioessays 38 (1):77-88.
    In metazoans, the extracellular matrix (ECM) provides a dynamic, heterogeneous microenvironment that has important supportive and instructive roles. Although the primary site of action of ECM proteins is extracellular, evidence is emerging for non‐canonical intracellular roles. Examples include osteopontin, thrombospondins, IGF‐binding protein 3 and biglycan, and relate to roles in transcription, cell‐stress responses, autophagy and cancer. These findings pose conceptual problems on how proteins signalled for secretion can be routed to the cytosol or nucleus, or can function in environments (...)
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  21.  9
    The Style Matrix.Sondra Bacharach - 2022 - In Jonathan Gilmore & Lydia Goehr (eds.), A Companion to Arthur C. Danto. Hoboken, NJ, USA: Wiley. pp. 248–255.
    Arthur Danto's style matrix brings together many facets of his thinking about philosophy and about art, particularly his intentionalism, art criticism, and historicism. This chapter presents the mechanics of the style matrix and offers modifications of the view in the light of certain criticisms. The style matrix has an interesting consequence for the range of artistic properties that can apply to artworks. In describing the style matrix, Danto relies on causal relations among artworks as a (...)
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  22.  55
    Quantum Mechanics as an Emergent Property of Ergodic Systems Embedded in the Zero-point Radiation Field.L. de la Peña, A. Valdés-Hernández & A. M. Cetto - 2009 - Foundations of Physics 39 (11):1240-1272.
    The present paper reveals (non-relativistic) quantum mechanics as an emergent property of otherwise classical ergodic systems embedded in a stochastic vacuum or zero-point radiation field (zpf). This result provides a theoretical basis for understanding recent numerical experiments in which a statistical analysis of an atomic electron interacting with the zpf furnishes the quantum distribution for the ground state of the H atom. The action of the zpf on matter is essential within the present approach, but it is the ergodic (...)
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  23.  15
    Synthesis and characterization of precipitation hardened amorphous matrix composite by mechanical alloying and pulse plasma sintering of Al65Cu20Ti15. [REVIEW]D. Roy, S. S. Singh, R. Mitra, M. Rosinski, A. Michalski, W. Lojkowski & I. Manna - 2009 - Philosophical Magazine 89 (12):1051-1061.
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  24. Stephen L. Adler, Quantum Theory as an Emergent Phenomenon: The Statistical Mechanics of Matrix Models as the Precursor of Quantum Field Theory. Cambridge: Cambridge University Press , 283 pp., $50.00. [REVIEW]GianCarlo Ghirardi - 2005 - Philosophy of Science 72 (4):642-645.
  25.  32
    Brain mechanisms of acoustic communication in humans and nonhuman primates: An evolutionary perspective.Hermann Ackermann, Steffen R. Hage & Wolfram Ziegler - 2014 - Behavioral and Brain Sciences 37 (6):529-546.
    Any account of “what is special about the human brain” (Passingham 2008) must specify the neural basis of our unique ability to produce speech and delineate how these remarkable motor capabilities could have emerged in our hominin ancestors. Clinical data suggest that the basal ganglia provide a platform for the integration of primate-general mechanisms of acoustic communication with the faculty of articulate speech in humans. Furthermore, neurobiological and paleoanthropological data point at a two-stage model of the phylogenetic evolution of this (...)
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  26.  89
    The Wentaculus: Density Matrix Realism Meets the Arrow of Time.Eddy Keming Chen - 2024 - In Angelo Bassi, Sheldon Goldstein, Roderich Tumulka & Nino Zanghi (eds.), Physics and the Nature of Reality: Essays in Memory of Detlef Dürr. Springer. pp. 87-104.
    In this paper, I characterize and elaborate on the “Wentaculus” theory, a new approach to time’s arrow in a quantum universe that offers a unified solution to the problems of what gives rise to the arrow of time and what the ontology of quantum mechanics is.
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  27. Quantum-information conservation. The problem about “hidden variables”, or the “conservation of energy conservation” in quantum mechanics: A historical lesson for future discoveries.Vasil Penchev - 2020 - Energy Engineering (Energy) eJournal (Elsevier: SSRN) 3 (78):1-27.
    The explicit history of the “hidden variables” problem is well-known and established. The main events of its chronology are traced. An implicit context of that history is suggested. It links the problem with the “conservation of energy conservation” in quantum mechanics. Bohr, Kramers, and Slaters (1924) admitted its violation being due to the “fourth Heisenberg uncertainty”, that of energy in relation to time. Wolfgang Pauli rejected the conjecture and even forecast the existence of a new and unknown then elementary (...)
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  28.  37
    Landau's density matrix in quantum electrodynamics.L. Diósi - 1990 - Foundations of Physics 20 (1):63-70.
    This paper is devoted to Landau's concept of the problem of damping in quantum mechanics. It shows that Landau's density matrix formalism should survive in the context of modern quantum electrodynamics. The correct generalized master equation has been derived for the reduced dynamics of the charges. The recent relativistic theory of spontaneous emission becomes reproducible.
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  29. Indeterminism in Quantum Mechanics: Beyond and/or Within.Vasil Penchev - 2020 - Development of Innovation eJournal (Elsevier: SSRN) 8 (68):1-5.
    The problem of indeterminism in quantum mechanics usually being considered as a generalization determinism of classical mechanics and physics for the case of discrete (quantum) changes is interpreted as an only mathematical problem referring to the relation of a set of independent choices to a well-ordered series therefore regulated by the equivalence of the axiom of choice and the well-ordering “theorem”. The former corresponds to quantum indeterminism, and the latter, to classical determinism. No other premises (besides the above (...)
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  30.  18
    The density matrix of scattered particles.Roger G. Newton - 1979 - Foundations of Physics 9 (11-12):929-935.
    The derivation of the expression for the density matrix of scattered particles in terms of that of the incident ones, taking different impact parameters into account, shows that under well-specified and realistic conditions, the final density matrix is of the same kind as the initial one. Thus the final mixed state after a collision can be used directly as the initial mixed state in a subsequent collision. Contrary to a recent claim by Band and Park, there are no (...)
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  31.  16
    Networking Mechanisms of Identity Formation.Inna Valerievna Miroshnichenko & Elena Vasilievna Morozova - 2017 - Cultura 14 (2):107-120.
    The authors prove and describe the action of new networking mechanisms of formation of identities which arise in the context of societal transformations of the modern society. The networking mechanisms of identity formation represent a complex of interrelated and interdependent practices in global information and communication space, promoting individual and collective identification, interiorization and reflection. The complex includes the mechanism of network communication, mechanism of reflexive involvement of a person into the public space, mechanism of network topos-structuring and mechanism of (...)
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  32.  18
    Networking Mechanisms of Identity Formation.Inna Valerievna Miroshnichenko & Elena Vasilievna Morozova - 2017 - Cultura 14 (2):85-120.
    The authors prove and describe the action of new networking mechanisms of formation of identities which arise in the context of societal transformations of the modern society. The networking mechanisms of identity formation represent a complex of interrelated and interdependent practices in global information and communication space, promoting individual and collective identification, interiorization and reflection. The complex includes the mechanism of network communication, mechanism of reflexive involvement of a person into the public space, mechanism of network topos-structuring and mechanism of (...)
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  33. Statistical mechanics and the ontological interpretation.D. Bohm & B. J. Hiley - 1996 - Foundations of Physics 26 (6):823-846.
    To complete our ontological interpretation of quantum theory we have to conclude a treatment of quantum statistical mechanics. The basic concepts in the ontological approach are the particle and the wave function. The density matrix cannot play a fundamental role here. Therefore quantum statistical mechanics will require a further statistical distribution over wave functions in addition to the distribution of particles that have a specified wave function. Ultimately the wave function of the universe will he required, but (...)
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  34. Time's Arrow in a Quantum Universe: On the Status of Statistical Mechanical Probabilities.Eddy Keming Chen - 2020 - In Valia Allori (ed.), Statistical Mechanics and Scientific Explanation: Determinism, Indeterminism and Laws of Nature. World Scientific. pp. 479–515.
    In a quantum universe with a strong arrow of time, it is standard to postulate that the initial wave function started in a particular macrostate---the special low-entropy macrostate selected by the Past Hypothesis. Moreover, there is an additional postulate about statistical mechanical probabilities according to which the initial wave function is a ''typical'' choice in the macrostate. Together, they support a probabilistic version of the Second Law of Thermodynamics: typical initial wave functions will increase in entropy. Hence, there are two (...)
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  35.  47
    Quantum mechanics of space and time.H. S. Green - 1978 - Foundations of Physics 8 (7-8):573-591.
    A formulation of relativistic quantum mechanics is presented independent of the theory of Hilbert space and also independent of the hypothesis of spacetime manifold. A hierarchy is established in the nondistributive lattice of physical ensembles, and it is shown that the projections relating different members of the hierarchy form a semigroup. It is shown how to develop a statistical theory based on the definition of a statistical operator. Involutions defined on the matrix representations of the semigroup are interpreted (...)
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  36.  16
    Entropic Mechanics: Towards a Stochastic Description of Quantum Mechanics.Vitaly Vanchurin - 2020 - Foundations of Physics 50 (1):40-53.
    We consider a stochastic process which is described by a continuous-time Markov chain on only short time-scales and constrained to conserve a number of hidden quantities on long time-scales. We assume that the transition matrix of the Markov chain is given and the conserved quantities are known to exist, but not explicitly given. To study the stochastic dynamics we propose to use the principle of stationary entropy production. Then the problem can be transformed into a variational problem for a (...)
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  37.  12
    Are 'Particles' in Quantum Mechanics "Just a Way of Talking"?Christian de Ronde & Raimundo Fernández Mouján - unknown
    In this work we discuss the widespread use and application of the notion of 'particle' within the standard understanding of quantum mechanics, trying to prove how it is not just an innocent and unproblematic “way of talking”, as it is often claimed, but the expression of an atomist metaphysics that represents rather a way of perceiving and thinking that inadvertently determines our understanding of the mathematical formalism and the experimental content of quantum mechanics. We show how the retention (...)
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  38. On the Role of Density Matrices in Bohmian Mechanics.Detlef Dürr, Sheldon Goldstein, Roderich Tumulka & Nino Zanghí - 2005 - Foundations of Physics 35 (3):449-467.
    It is well known that density matrices can be used in quantum mechanics to represent the information available to an observer about either a system with a random wave function (“statistical mixture”) or a system that is entangled with another system (“reduced density matrix”). We point out another role, previously unnoticed in the literature, that a density matrix can play: it can be the “conditional density matrix,” conditional on the configuration of the environment. A precise definition (...)
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  39.  64
    On the actual measurability of the density matrix of a decaying system by means of measurements on the decay products.S. Bergia, F. Cannata, A. Cornia & R. Livi - 1980 - Foundations of Physics 10 (9-10):723-730.
    The density matrix ρ describing a decaying system can be expressed in terms of correlations among observables belonging to the subsystems. Due to this structure and to the difficulties in measuring higher rank tensors of decay products for a single decay event, it is found that the mean value of ρ cannot be determined, in general, from measurements on the decay products. We also discuss the consequences of this conclusion as far as tests of quantum mechanics are concerned.
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  40. The equivalence myth of quantum mechanics —Part I.F. A. Muller - 1997 - Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics 28 (1):35-61.
    The author endeavours to show two things: first, that Schrödingers (and Eckarts) demonstration in March (September) 1926 of the equivalence of matrix mechanics, as created by Heisenberg, Born, Jordan and Dirac in 1925, and wave mechanics, as created by Schrödinger in 1926, is not foolproof; and second, that it could not have been foolproof, because at the time matrix mechanics and wave mechanics were neither mathematically nor empirically equivalent. That they were is the Equivalence (...)
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  41.  40
    A mechanical model for the formation of vascular networks in vitro.D. Manoussaki, S. R. Lubkin, R. B. Vemon & J. D. Murray - 1996 - Acta Biotheoretica 44 (3-4):271-282.
    Endothelial cells, when cultured on gelled basement membrane matrix exert forces of tension through which they deform the matrix and at the same time they aggregate into clusters. The cells eventually form a network of cord-like structures connecting cell aggregates. In this network, almost all of the matrix has been pulled underneath the cell cords and cell clusters. This phenomenon has been proposed as a possible model for the growth and development of planar vascular systems in vitro. (...)
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  42. The equivalence myth of quantum mechanics—part II.F. A. Muller - 1997 - Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics 28 (2):219-247.
    The author endeavours to show two things: first, that Schrödingers (and Eckarts) demonstration in March (September) 1926 of the equivalence of matrix mechanics, as created by Heisenberg, Born, Jordan and Dirac in 1925, and wave mechanics, as created by Schrödinger in 1926, is not foolproof; and second, that it could not have been foolproof, because at the time matrix mechanics and wave mechanics were neither mathematically nor empirically equivalent. That they were is the Equivalence (...)
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  43.  7
    Mechanisms of neural crest cell migration.Marianne Bronner-Fraser - 1993 - Bioessays 15 (4):221-230.
    Neural crest cells are remarkable in their extensive and stereotypic patterns of migration. The pathways of neural crest migration have been documented by cell marking techniques, including interspecific neural tube grafts, immunocytochemistry and Dil‐labelling. In the trunk, neural crest cells migrate dorsally under the skin or ventrally through the somites, where they move in a segmental fashion through the rostral half of each sclerotome. The segmental migration of neural crest cells appears to be prescribed by the somites, perhaps by an (...)
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  44.  24
    The Mechanics of the Mind. [REVIEW]F. J. - 1972 - Review of Metaphysics 26 (1):162-164.
    The Mechanics of the Mind, in the words of its author, "is an attempt to interpret the phenomenon of mind in terms of the physiological processes of the nervous system and to explore the philosophical implications of a realistically conceived theory." The first four chapters of the book is little more than a survey of some neurophysiological, cognitive, psychosocial and clinical experimental data, the consideration of which presumably leads one to the conclusion that behavior is strictly neuronic. This extensive (...)
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  45.  27
    Nonrelativistic Quantum Mechanics with Fundamental Environment.Ashot S. Gevorkyan - 2011 - Foundations of Physics 41 (3):509-515.
    Spontaneous transitions between bound states of an atomic system, “Lamb Shift” of energy levels and many other phenomena in real nonrelativistic quantum systems are connected within the influence of the quantum vacuum fluctuations (fundamental environment (FE)) which are impossible to consider in the limits of standard quantum-mechanical approaches. The joint system “quantum system (QS) + FE” is described in the framework of the stochastic differential equation (SDE) of Langevin-Schrödinger (L-Sch) type, and is defined on the extended space R 3 ⊗ (...)
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  46.  21
    Foundations of Quantum Mechanics: On Rotations by 4pi for Half-Integral Spin Particles.L. S. F. Olavo - 2015 - Foundations of Physics 45 (11):1483-1494.
    Rotations in Quantum Mechanics are a very well-known subject. When one is faced with rotations related to the SO group, for instance, all the underlying operators are well-known and built from their classical counterparts. However, when it comes to represent rotations related to the SU group, it is always argued that there is no classical counterpart from which the expressions for the quantum mechanical operators can be built. The approach is always done using matrix representation. In the way (...)
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  47. Essays on the Metaphysics of Quantum Mechanics.Eddy Keming Chen - 2019 - Dissertation, Rutgers University, New Brunswick
    What is the proper metaphysics of quantum mechanics? In this dissertation, I approach the question from three different but related angles. First, I suggest that the quantum state can be understood intrinsically as relations holding among regions in ordinary space-time, from which we can recover the wave function uniquely up to an equivalence class (by representation and uniqueness theorems). The intrinsic account eliminates certain conventional elements (e.g. overall phase) in the representation of the quantum state. It also dispenses with (...)
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  48.  17
    On the Quantum Mechanical Measurement Process.H. W. L. Naus - 2021 - Foundations of Physics 51 (1):1-13.
    The quantum mechanical measurement process is analyzed by means of an explicit generic model describing the interaction between object and measuring device. The solution of the Schrödinger equation for the whole system reflects the ‘collapse’ of the object wave function. A necessary condition is a sufficiently sharply peaked initial measurement device wave function, which is guaranteed in its classical limit. With this assumption, it is in particular proven that the off-diagonal elements of the object density matrix vanish. This study (...)
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    The new quantum mechanics.George Birtwistle - 1928 - Cambridge [Eng.]: University Press.
    George Birtwistle (1877–1929) published The New Quantum Mechanics in 1928. His stated aim was to give a detailed account of work which had brought the relatively new subject of quantum mechanics to the fore in the previous few years. The earlier chapters give a restatement of Alfred Landé's theory of multiplets which reconciles it with the new mechanics which follow. Later chapters present the matrix theory of Heisenberg, the q-number theory of Dirac and the wave (...) of Schroedinger, and synthesise new theories, statistics and controversies in the work of de Broglie, Bose, Einstein, Fermi and Dirac. The book gives a complete overview of the state of quantum mechanics at the end of the second decade of the twentieth century, making it a valuable benchmark for historians of science and mathematicians alike. (shrink)
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  50.  22
    Biological replication by quantum mechanical interactions.L. Bass - 1977 - Foundations of Physics 7 (3-4):221-231.
    Wigner's quantum mechanical formulation of the problem of biological replication is examined with special reference to DNA. His necessary condition for replication is that the number of independent equations in his formulation should not exceed the number of unknowns. Explicit hypotheses concerning the relevant collision matrix are proposed without assuming biotonic modifications of quantum mechanics. Schrödinger's description of the gene as a low-temperature solid, combined with the concept of template, is given mathematical expression which fails to satisfy Wigner's (...)
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