Results for 'density matrix'

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  1.  72
    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 (...)
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  2.  84
    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 (...)
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  3.  12
    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 (...)
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  4.  7
    Density Matrix Description of Fast and Slow Light Propagation in Sodium Vapour.Abu Mohamed Alhasan - 2009 - In Institute of Physics Krzysztof Stefanski (ed.), Open Systems and Information Dynamics. World Scientific Publishing Company. pp. 103-125.
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  5.  70
    Quantum States of a Time-Asymmetric Universe: Wave Function, Density Matrix, and Empirical Equivalence.Eddy Keming Chen - 2019 - Dissertation, Rutgers University - New Brunswick
    What is the quantum state of the universe? Although there have been several interesting suggestions, the question remains open. In this paper, I consider a natural choice for the universal quantum state arising from the Past Hypothesis, a boundary condition that accounts for the time-asymmetry of the universe. The natural choice is given not by a wave function but by a density matrix. I begin by classifying quantum theories into two types: theories with a fundamental wave function and (...)
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  6.  12
    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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  7.  55
    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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  8.  28
    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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  9.  14
    Is There Density Matrix Realism?Shan Gao - manuscript
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  10.  30
    Comments on “The Density Matrix of Scattered Particles”.William Band & James L. Park - 1979 - Foundations of Physics 9 (11-12):937-938.
    This note, in rejoinder to a paper by Newton critical of our analysis of certain limitations of quantum scattering theory, seeks to acknowledge and to clarify the disparate interests of the two conflicting articles.
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  11.  5
    Interpreting the Density Matrix of the Universe.Don N. Page - 1991 - In A. Ashtekar & J. Stachel (eds.), Conceptual Problems of Quantum Gravity. Birkhauser. pp. 1--116.
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  12.  68
    The Hyperbolic Geometric Structure of the Density Matrix for Mixed State Qubits.Abraham A. Ungar - 2002 - Foundations of Physics 32 (11):1671-1699.
    Density matrices for mixed state qubits, parametrized by the Bloch vector in the open unit ball of the Euclidean 3-space, are well known in quantum computation theory. We bring the seemingly structureless set of all these density matrices under the umbrella of gyrovector spaces, where the Bloch vector is treated as a hyperbolic vector, called a gyrovector. As such, this article catalizes and supports interdisciplinary research spreading from mathematical physics to algebra and geometry. Gyrovector spaces are mathematical objects (...)
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  13.  4
    Interpretation of Porosity and Fluid Constituents From Well Logs Using an Interactive Neutron-Density Matrix Scale.Olabode Ijasan, Carlos Torres-Verdín & William E. Preeg - 2013 - Interpretation: SEG 1 (2):T143-T155.
    Neutron and density logs are important borehole measurements for estimating reservoir capacity and inferring saturating fluids. The neutron log, measuring the hydrogen index, is commonly expressed in apparent water-filled porosity units assuming a constant matrix lithology whereby it is not always representative of actual pore fluid. By contrast, a lithology-independent porosity calculation from nuclear magnetic resonance and/or core measurements provides reliable evaluations of reservoir capacity. In practice, not all wells include core or NMR measurements. We discovered an interpretation (...)
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  14.  92
    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 or a system that is entangled with another system. 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 can be given in (...)
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  15.  23
    Matrix Models as Non-Local Hidden Variables Theories.Lee Smolin - unknown
    It is shown that the matrix models which give non-perturbative definitions of string and M theory may be interpreted as non-local hidden variables theories in which the quantum observables are the eigenvalues of the matrices while their entries are the non-local hidden variables. This is shown by studying the bosonic matrix model at finite temperature, with T taken to scale as 1/N, with N the rank of the matrices. For large N the eigenvalues of the matrices undergo Brownian (...)
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  16.  23
    Uniform Probability Distribution Over All Density Matrices.Eddy Keming Chen & Roderich Tumulka - 2022 - Quantum Studies: Mathematics and Foundations.
    Let ℋ be a finite-dimensional complex Hilbert space and D the set of density matrices on ℋ, i.e., the positive operators with trace 1. Our goal in this note is to identify a probability measure u on D that can be regarded as the uniform distribution over D. We propose a measure on D, argue that it can be so regarded, discuss its properties, and compute the joint distribution of the eigenvalues of a random density matrix distributed (...)
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  17.  18
    Asymptotic Distribution of Density-Dependent Stage-Grouped Population Dynamics Models.Mélanie Zetlaoui, Nicolas Picard & Avner Bar-Hen - 2008 - Acta Biotheoretica 56 (1-2):137-155.
    Matrix models are widely used in biology to predict the temporal evolution of stage-structured populations. One issue related to matrix models that is often disregarded is the sampling variability. As the sample used to estimate the vital rates of the models are of finite size, a sampling error is attached to parameter estimation, which has in turn repercussions on all the predictions of the model. In this study, we address the question of building confidence bounds around the predictions (...)
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  18. Implementation of the Spark Technique in a Matrix Distributed Computing Algorithm.Korhan Cengiz & Ying Wang - 2022 - Journal of Intelligent Systems 31 (1):660-671.
    Two analyzes of Spark engine performance strategies to implement the Spark technique in a matrix distributed computational algorithm, the multiplication of a sparse multiplication operational test model. The dimensions of the two input sparse matrices have been fixed to 30,000 × 30,000, and the density of the input matrix have been changed. The experimental results show that when the density reaches about 0.3, the original dense matrix multiplication performance can outperform the sparse-sparse matrix multiplication, (...)
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  19. Adaptive Mixed-Attribute Data Clustering Method Based on Density Peaks.Shihua Liu - 2022 - Complexity 2022:1-13.
    The clustering of mixed-attribute data is a vital and challenging issue. The density peaks clustering algorithm brings us a simple and efficient solution, but it mainly focuses on numerical attribute data clustering and cannot be adaptive. In this paper, we studied the adaptive improvement method of such an algorithm and proposed an adaptive mixed-attribute data clustering method based on density peaks called AMDPC. In this algorithm, we used the unified distance metric of mixed-attribute data to construct the distance (...)
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  20.  30
    Modeling the Population Dynamics of Annual Plants with Seed Bank and Density Dependent Effects.Marc Jarry, Mohamed Khaladi, Martine Hossaert-McKey & Doyle McKey - 1995 - Acta Biotheoretica 43 (1-2):53-65.
    A model is proposed for the population dynamics of an annual plant (Sesbania vesicaria) with a seed bank (i.e. in which a proportion of seeds remain dormant for at least one year). A simple linear matrix model is deduced from the life cycle graph. The dominant eigenvalue of the projection matrix is estimated from demographic parameters derived from field studies. The estimated values for population growth rate () indicates that the study population should be experiencing a rapid exponential (...)
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  21.  13
    Petrophysical Rock Classification in the Cotton Valley Tight-Gas Sandstone Reservoir with a Clustering Pore-System Orthogonality Matrix.Chicheng Xu & Carlos Torres-Verdín - 2014 - Interpretation: SEG 2 (1):T13-T23.
    Petrophysical rock classification is an important component of the interpretation of core data and well logs acquired in complex reservoirs. Tight-gas sandstones exhibit large variability in all petrophysical properties due to complex pore topology resulting from diagenesis. Conventional methods that rely dominantly on hydraulic radius to classify and rank reservoir rocks are prone to rock misclassification at the low-porosity and low-permeability end of the spectrum. We introduce a bimodal Gaussian density function to quantify complex pore systems in terms of (...)
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  22. 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 (...)
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  23. 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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  24. 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 first-order (...)
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  25. Is - kTr( Ln ) the Entropy in Quantum Mechanics.Orly Shenker - 1999 - British Journal for the Philosophy of Science 50 (1):33-48.
    In quantum mechanics, the expression for entropy is usually taken to be -kTr(ln), where is the density matrix. The convention first appears in Von Neumann's Mathematical Foundations of Quantum Mechanics. The argument given there to justify this convention is the only one hitherto offered. All the arguments in the field refer to it at one point or another. Here this argument is shown to be invalid. Moreover, it is shown that, if entropy is -kTr(ln), then perpetual motion machines (...)
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  26.  84
    The Basis Problem in Many-Worlds Theories.Henry P. Stapp - unknown
    It is emphasized that a many-worlds interpretation of quantum theory exists only to the extent that the associated basis problem is solved. The core basis problem is that the robust enduring states specified by environmental decoherence effects are essentially Gaussian wave packets that form continua of non-orthogonal states. Hence they are not a discrete set of orthogonal basis states to which finite probabilities can be assigned by the usual rules. The natural way to get an orthogonal basis without going outside (...)
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  27.  58
    Propensity, Probability, and Quantum Theory.Leslie E. Ballentine - 2016 - Foundations of Physics 46 (8):973-1005.
    Quantum mechanics and probability theory share one peculiarity. Both have well established mathematical formalisms, yet both are subject to controversy about the meaning and interpretation of their basic concepts. Since probability plays a fundamental role in QM, the conceptual problems of one theory can affect the other. We first classify the interpretations of probability into three major classes: inferential probability, ensemble probability, and propensity. Class is the basis of inductive logic; deals with the frequencies of events in repeatable experiments; describes (...)
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  28. All the Bell Inequalities.Asher Peres - 1999 - Foundations of Physics 29 (4):589-614.
    Bell inequalities are derived for any number of observers, any number of alternative setups for each one of them and any number of distinct outcomes for each experiment. It is shown that if a physical system consists of several distant subsystems, and if the results of tests performed on the latter are determined by local variables with objective values, then the joint probabilities for triggering any given set of distant detectors are convex combinations of a finite number of Boolean arrays, (...)
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  29. Entanglement Between Degrees of Freedom in a Single-Particle System Revealed in Neutron Interferometry.Yuji Hasegawa - 2012 - Foundations of Physics 42 (1):29-45.
    Initially Einstein, Podolsky, and Rosen (EPR) and later Bell shed light on the non-local properties exhibited by subsystems in quantum mechanics. Separately, Kochen and Specker analyzed sets of measurements of compatible observables and found that a consistent coexistence of these results is impossible, i.e., quantum indefiniteness of measurement results. As a consequence, quantum contextuality, a more general concept compared to non-locality, leads to striking phenomena predicted by quantum theory. Here, we report neutron interferometric experiments which investigate entangled states in a (...)
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  30.  31
    Bohmian Trajectories Post-Decoherence.D. M. Appleby - 1999 - Foundations of Physics 29 (12):1885-1916.
    The role of the environment in producing the correct classical limit in the Bohm interpretation of quantum mechanics is investigated, in the context of a model of quantum Brownian motion. One of the effects of the interaction is to produce a rapid approximate diagonalisation of the reduced density matrix in the position representation. This effect is, by itself, insufficient to produce generically quasi-classical behaviour of the Bohmian trajectory. However, it is shown that, if the system particle is initially (...)
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  31.  67
    Normal Typicality and Von Neumann's Quantum Ergodic Theorem.Sheldon Goldstein & Roderich Tumulka - unknown
    We discuss the content and significance of John von Neumann’s quantum ergodic theorem (QET) of 1929, a strong result arising from the mere mathematical structure of quantum mechanics. The QET is a precise formulation of what we call normal typicality, i.e., the statement that, for typical large systems, every initial wave function ψ0 from an energy shell is “normal”: it evolves in such a way that |ψt ψt| is, for most t, macroscopically equivalent to the micro-canonical density matrix. (...)
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  32.  11
    Statistical Properties of Strongly Correlated Quantum Liquids.M. L. Ristig & K. A. Gernoth - 2010 - Foundations of Physics 40 (9-10):1253-1262.
    Modern microscopic theory is employed to construct a powerful analytical algorithm that permits a clear description of characteristic features of strongly correlated quantum fluids in thermodynamic equilibrium. Using recently developed formal results we uncover an intricate relationship between strongly correlated systems and free quantum gases of appropriately defined constituents. The latter entities are precisely defined renormalized bosons or fermions. They carry all the information contained in the statistical correlations of the strongly interacting many-particle system by virtue of their effective masses. (...)
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  33.  23
    Born Again.Don N. Page - unknown
    A simple proof is given that the probabilities of observations in a large universe are not given directly by Born’s rule as the expectation values of projection operators in a global quantum state of the entire universe. An alternative procedure is proposed for constructing an averaged density matrix for a random small region of the universe and then calculating observational probabilities indirectly by Born’s rule as conditional probabilities, conditioned upon the existence of an observation.
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  34. Welcome to the Fuzzy-Verse.Eddy Keming Chen - 2020 - New Scientist 247 (3298):36-40.
    We expect the laws of nature that describe the universe to be exact, but what if that isn't true? In this popular science article, I discuss the possibility that some candidate fundamental laws of nature, such as the Past Hypothesis, may be vague. This possibility is in conflict with the idea that the fundamental laws of nature can always and faithfully be described by classical mathematics. -/- [Bibliographic note: this article is featured on the magazine website under a different title (...)
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  35.  32
    Probabilities and Quantum Reality: Are There Correlata? [REVIEW]Robert B. Griffiths - 2003 - Foundations of Physics 33 (10):1423-1459.
    Any attempt to introduce probabilities into quantum mechanics faces difficulties due to the mathematical structure of Hilbert space, as reflected in Birkhoff and von Neumann's proposal for a quantum logic. The (consistent or decoherent) histories solution is provided by its single framework rule, an approach that includes conventional (Copenhagen) quantum theory as a special case. Mermin's Ithaca interpretation addresses the same problem by defining probabilities which make no reference to a sample space or event algebra (“correlations without correlata”). But this (...)
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  36.  9
    A Gleason-Type Theorem for Any Dimension Based on a Gambling Formulation of Quantum Mechanics.Alessio Benavoli, Alessandro Facchini & Marco Zaffalon - 2017 - Foundations of Physics 47 (7):991-1002.
    Based on a gambling formulation of quantum mechanics, we derive a Gleason-type theorem that holds for any dimension n of a quantum system, and in particular for \. The theorem states that the only logically consistent probability assignments are exactly the ones that are definable as the trace of the product of a projector and a density matrix operator. In addition, we detail the reason why dispersion-free probabilities are actually not valid, or rational, probabilities for quantum mechanics, and (...)
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  37.  15
    Wave Packet Reduction in Quantum Mechanics: A Model of a Measuring Apparatus. [REVIEW]M. Cini, M. De Maria, G. Mattioli & F. Nicolò - 1979 - Foundations of Physics 9 (7-8):479-500.
    We investigate the problem of “wave packet reduction” in quantum mechanics by solving the Schrödinger equation for a system composed of a model measuring apparatusM interacting with a microscopic objects. The “instrument” is intended to be somewhat more realistic than others previously proposed, but at the same time still simple enough to lead to an explicit solution for the time-dependent density matrix. It turns out that,practically, everything happens as if the wave packet reduction had occurred. This is a (...)
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  38.  34
    Time Evolution in Macroscopic Systems. I. Equations of Motion.W. T. Grandy - 2004 - Foundations of Physics 34 (1):1-20.
    The concept of entropy in nonequilibrium macroscopic systems is investigated in the light of an extended equation of motion for the density matrix obtained in a previous study. It is found that a time-dependent information entropy can be defined unambiguously, but it is the time derivative or entropy production that governs ongoing processes in these systems. The differences in physical interpretation and thermodynamic role of entropy in equilibrium and nonequilibrium systems is emphasized and the observable aspects of entropy (...)
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  39. The Metaphysics of Decoherence.Antonio Vassallo & Davide Romano - 2021 - Erkenntnis:1-23.
    The paper investigates the type of realism that best suits the framework of decoherence taken at face value without postulating a plurality of worlds, or additional hidden variables, or non-unitary dynamical mechanisms. It is argued that this reading of decoherence leads to an extremely radical type of perspectival realism, especially when cosmological decoherence is considered.
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  40. Time Evolution in Macroscopic Systems. II. The Entropy.W. T. Grandy - 2004 - Foundations of Physics 34 (1):21-57.
    The concept of entropy in nonequilibrium macroscopic systems is investigated in the light of an extended equation of motion for the density matrix obtained in a previous study. It is found that a time-dependent information entropy can be defined unambiguously, but it is the time derivative or entropy production that governs ongoing processes in these systems. The differences in physical interpretation and thermodynamic role of entropy in equilibrium and nonequilibrium systems is emphasized and the observable aspects of entropy (...)
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  41. On Classical and Quantum Logical Entropy.David Ellerman - manuscript
    The notion of a partition on a set is mathematically dual to the notion of a subset of a set, so there is a logic of partitions dual to Boole's logic of subsets (Boolean logic is usually mis-specified as "propositional" logic). The notion of an element of a subset has as its dual the notion of a distinction of a partition (a pair of elements in different blocks). Boole developed finite logical probability as the normalized counting measure on elements of (...)
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  42.  30
    Heisenberg Picture and Reality.B. D'Espagnat - 1992 - Foundations of Physics 22 (12):1495-1504.
    The idea is discussed according to which, in the Heisenberg picture, the operators correspond to the dynamic properties while the density matrix corresponds to our knowledge. A simple, soluble model is made use of in order to determine in what way this idea needs to be refined and what it then tells us about the relationship of reality and physics.
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  43. Fast and Robust Image Encryption Scheme Based on Quantum Logistic Map and Hyperchaotic System.Nehal Abd El-Salam Mohamed, Aliaa Youssif & Hala Abdel-Galil El-Sayed - 2022 - Complexity 2022:1-20.
    Topic of quantum chaos has begun to draw increasing attention in recent years. So, to ensure the security of digital image, an image encryption algorithm based on combining a hyperchaotic system and quantum 3D logistic map is proposed. This algorithm is applied in four stages. Initially, the key generator builds upon the foundation of mean for any row or column of the edges of the plain image. Its output value is used to yield initial conditions and parameters of the proposed (...)
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  44.  13
    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 (...)
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  45.  6
    An Intricate Quantum Statistical Effect and the Foundation of Quantum Mechanics.Fritz W. Bopp - 2021 - Foundations of Physics 51 (1):1-21.
    An intricate quantum statistical effect guides us to a deterministic, non-causal quantum universe with a given fixed initial and final state density matrix. A concept is developed on how and where something like macroscopic physics can emerge. However, the concept does not allow philosophically crucial free will decisions. The quantum world and its conjugate evolve independently, and one can replace fixed final states on each side just with a common matching one. This change allows for external manipulations done (...)
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  46. An Argument for 4d Blockworld From a Geometric Interpretation of Non-Relativistic Quantum Mechanics.Michael Silberstein, W. M. Stuckey & Michael Cifone - unknown
    We use a new, distinctly “geometrical” interpretation of non-relativistic quantum mechanics (NRQM) to argue for the fundamentality of the 4D blockworld ontology. We argue for a geometrical interpretation whose fundamental ontology is one of spacetime relations as opposed to constructive entities whose time-dependent behavior is governed by dynamical laws. Our view rests on two formal results: Kaiser (1981 & 1990), Bohr & Ulfbeck (1995) and Anandan, (2003) showed independently that the Heisenberg commutation relations of NRQM follow from the relativity of (...)
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  47.  30
    Some Fundamental Difficulties with Quantum Mechanical Collision Theory.William Band & James L. Park - 1978 - Foundations of Physics 8 (9-10):677-694.
    When quantum scattering theory is applied strictly from the point of view that the state of a system is completely described by the density matrix, whether pure or mixed, it is not possible to assume that colliding particles are at all times individually in pure states. Exact results are significantly different from conventionally accepted approximations. In particular, it turns out that the cross section as ordinarily defined in theS-matrix formalism is an adequate parameter for deciding the outcome (...)
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  48. 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 we (...)
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  49. Principles of Laser Spectroscopy and Quantum Optics.Paul R. Berman & Vladimir S. Malinovsky - 2010 - Princeton University Press.
    Principles of Laser Spectroscopy and Quantum Optics is an essential textbook for graduate students studying the interaction of optical fields with atoms. It also serves as an ideal reference text for researchers working in the fields of laser spectroscopy and quantum optics. The book provides a rigorous introduction to the prototypical problems of radiation fields interacting with two- and three-level atomic systems. It examines the interaction of radiation with both atomic vapors and condensed matter systems, the density matrix (...)
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  50.  77
    Reversing the Arrow of Explanation in the Relational Blockworld: Why Temporal Becoming, the Dynamical Brain and the External World Are All "in the Mind".W. M. Stuckey, Michael Silberstein & Michael Cifone - unknown
    We introduce the Relational Blockworld (RBW) as a paradigm for deflating the mysteries associated with quantum non-separability/non-locality and the measurement problem. We begin by describing how the relativity of simultaneity implies the blockworld, which has an explanatory potential subsuming both dynamical and relational explanations. It is then shown how the canonical commutation relations fundamental to non-relativistic quantum mechanics follow from the relativity of simultaneity. Therefore, quantum mechanics has at its disposal the full explanatory power of the blockworld. Quantum mechanics exploits (...)
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