Results for 'Self‐adjoint operator'

993 found
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  1.  23
    Self-adjointness of momentum operators in generalized coordinates.J. M. Domingos & M. H. Caldeira - 1984 - Foundations of Physics 14 (2):147-154.
    The aim of this paper is to contribute to the clarification of concepts usually found in books on quantum mechanics, aided by knowledge from the field of the theory of operators in Hilbert space. Frequently the basic distinction between bounded and unbounded operators is not established in books on quantum mechanics. It is repeatedly overlooked that the condition for an unbounded operator to be symmetric (Hermitian) is not sufficient to make it self-adjoint. To make things worse, nearly all operators (...)
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  2. Essential self-adjointness: implications for determinism and the classical–quantum correspondence.John Earman - 2009 - Synthese 169 (1):27-50.
    It is argued that seemingly “merely technical” issues about the existence and uniqueness of self-adjoint extensions of symmetric operators in quantum mechanics have interesting implications for foundations problems in classical and quantum physics. For example, pursuing these technical issues reveals a sense in which quantum mechanics can cure some of the forms of indeterminism that crop up in classical mechanics; and at the same time it reveals the possibility of a form of indeterminism in quantum mechanics that is quite distinct (...)
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  3.  26
    The self-adjointness of Hermitian Hamiltonians.Chengjun Zhu & John R. Klauder - 1993 - Foundations of Physics 23 (4):617-631.
    For several examples of Hermitian operators, the issues involved in their possible self-adjoint extension are shown to conform with recognizable properties in the solutions to the associated classical equations of motion. This result confirms the assertion made in an earlier paper (Ref. 1) that there are sufficient classical “symptoms” to diagnose any quantum “illness.”.
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  4.  66
    Idealizations, essential self-adjointness, and minimal model explanation in the Aharonov–Bohm effect.Shech Elay - 2018 - Synthese 195 (11):4839-4863.
    Two approaches to understanding the idealizations that arise in the Aharonov–Bohm effect are presented. It is argued that a common topological approach, which takes the non-simply connected electron configuration space to be an essential element in the explanation and understanding of the effect, is flawed. An alternative approach is outlined. Consequently, it is shown that the existence and uniqueness of self-adjoint extensions of symmetric operators in quantum mechanics have important implications for philosophical issues. Also, the alleged indispensable explanatory role of (...)
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  5. Quantization by parts, self-adjoint extensions, and a novel derivation of the Josephson equation in superconductivity.K. Kong Wan & R. H. Fountain - 1996 - Foundations of Physics 26 (9):1165-1199.
    There has been a lot of interest in generalizing orthodox quantum mechanics to include POV measures as observables, namely as unsharp obserrables. Such POV measures are related to symmetric operators. We have argued recently that only maximal symmetric operators should describe observables.1 This generalization to maximal symmetric operators has many physical applications. One application is in the area of quantization. We shall discuss a scheme, to he called quantization by parts,which can systematically deal with what may be called quantum circuits. (...)
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  6. Toward a constructive theory of unbounded linear operators.Feng Ye - 2000 - Journal of Symbolic Logic 65 (1):357-370.
    We show that the following results in the classical theory of unbounded linear operators on Hilbert spaces can be proved within the framework of Bishop's constructive mathematics: the Kato-Rellich theorem, the spectral theorem, Stone's theorem, and the self-adjointness of the most common quantum mechanical operators, including the Hamiltonians of electro-magnetic fields with some general forms of potentials.
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  7.  63
    The Axiom of Choice in Quantum Theory.Norbert Brunner, Karl Svozil & Matthias Baaz - 1996 - Mathematical Logic Quarterly 42 (1):319-340.
    We construct peculiar Hilbert spaces from counterexamples to the axiom of choice. We identify the intrinsically effective Hamiltonians with those observables of quantum theory which may coexist with such spaces. Here a self adjoint operator is intrinsically effective if and only if the Schrödinger equation of its generated semigroup is soluble by means of eigenfunction series expansions.
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  8.  41
    Considerable Sets of Linear Operators in Hilbert Spaces as Operator Generalized Effect Algebras.Jan Paseka & Zdenka Riečanová - 2011 - Foundations of Physics 41 (10):1634-1647.
    We show that considerable sets of positive linear operators namely their extensions as closures, adjoints or Friedrichs positive self-adjoint extensions form operator (generalized) effect algebras. Moreover, in these cases the partial effect algebraic operation of two operators coincides with usual sum of operators in complex Hilbert spaces whenever it is defined. These sets include also unbounded operators which play important role of observables (e.g., momentum and position) in the mathematical formulation of quantum mechanics.
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  9. The Quantum Logic of Direct-Sum Decompositions: The Dual to the Quantum Logic of Subspaces.David Ellerman - 2017
    Since the pioneering work of Birkhoff and von Neumann, quantum logic has been interpreted as the logic of (closed) subspaces of a Hilbert space. There is a progression from the usual Boolean logic of subsets to the "quantum logic" of subspaces of a general vector space--which is then specialized to the closed subspaces of a Hilbert space. But there is a "dual" progression. The notion of a partition (or quotient set or equivalence relation) is dual (in a category-theoretic sense) to (...)
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  10.  31
    How many properties of spin does a particle have?Alberto Corti & Marco Sanchioni - 2021 - Studies in History and Philosophy of Science Part A:111–121.
    A common assumption in non-relativistic quantum mechanics is that self-adjoint operators mathematically represent properties of quantum systems. Focusing on spin, we argue that a natural view considers observables as determinable properties and their eigenvalues as their corresponding determinates. We provide a taxonomy of the different views that one can hold, once it is accepted that spin can be modelled with the determinable-determinate relation. In particular, we present the two main families of views, dubbed Spin Monism and Pluralism, and we show (...)
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  11. Quantum physics and the identity of indiscernibles.Steven French & Michael Redhead - 1988 - British Journal for the Philosophy of Science 39 (2):233-246.
    Department of History and Philosophy of Science. University of Cambridge, Free School Lane, Cambridge CB2 3RH This paper is concerned with the question of whether atomic particles of the same species, i. e. with the same intrinsic state-independent properties of mass, spin, electric charge, etc, violate the Leibnizian Principle of the Identity of Indiscernibles, in the sense that, while there is more than one of them, their state-dependent properties may also all be the same. The answer depends on what exactly (...)
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  12.  82
    Transfer Principle in Quantum Set Theory.Masanao Ozawa - 2007 - Journal of Symbolic Logic 72 (2):625 - 648.
    In 1981, Takeuti introduced quantum set theory as the quantum counterpart of Boolean valued models of set theory by constructing a model of set theory based on quantum logic represented by the lattice of closed subspaces in a Hilbert space and showed that appropriate quantum counterparts of ZFC axioms hold in the model. Here, Takeuti's formulation is extended to construct a model of set theory based on the logic represented by the lattice of projections in an arbitrary von Neumann algebra. (...)
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  13.  60
    Nonideal quantum measurements.Hans Martens & Willem M. de Muynck - 1990 - Foundations of Physics 20 (3):255-281.
    A partial ordering in the class of observables (∼ positive operator-valued measures, introduced by Davies and by Ludwig) is explored. The ordering is interpreted as a form of nonideality, and it allows one to compare ideal and nonideal versions of the same observable. Optimality is defined as maximality in the sense of the ordering. The framework gives a generalization of the usual (implicit) definition of self-adjoint operators as optimal observables (von Neumann), but it can, in contrast to this latter (...)
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  14. The Kochen - Specker theorem in quantum mechanics: a philosophical comment (part 1).Vasil Penchev - 2013 - Philosophical Alternatives 22 (1):67-77.
    Non-commuting quantities and hidden parameters – Wave-corpuscular dualism and hidden parameters – Local or nonlocal hidden parameters – Phase space in quantum mechanics – Weyl, Wigner, and Moyal – Von Neumann’s theorem about the absence of hidden parameters in quantum mechanics and Hermann – Bell’s objection – Quantum-mechanical and mathematical incommeasurability – Kochen – Specker’s idea about their equivalence – The notion of partial algebra – Embeddability of a qubit into a bit – Quantum computer is not Turing machine – (...)
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  15. A topos perspective on the kochen-Specker theorem: I. Quantum states as generalised valuations.Chris Isham & Jeremy Butterfield - unknown
    Any attempt to construct a realist interpretation of quantum theory founders on the Kochen-Specker theorem, which asserts the impossibility of assigning values to quantum quantities in a way that preserves functional relations between them. We construct a new type of valuation which is defined on all operators, and which respects an appropriate version of the functional composition principle. The truth-values assigned to propositions are (i) contextual; and (ii) multi-valued, where the space of contexts and the multi-valued logic for each context (...)
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  16.  4
    The Formalisms of Quantum Mechanics: An Introduction.Francois David - 2015 - Cham: Imprint: Springer.
    These lecture notes present a concise and introductory, yet as far as possible coherent, view of the main formalizations of quantum mechanics and of quantum field theories, their interrelations and their theoretical foundations. The "standard" formulation of quantum mechanics (involving the Hilbert space of pure states, self-adjoint operators as physical observables, and the probabilistic interpretation given by the Born rule) on one hand, and the path integral and functional integral representations of probabilities amplitudes on the other, are the standard tools (...)
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  17.  50
    Gauge Transformations for a Driven Quantum Particle in an Infinite Square Well.Stefan Weigert - 1999 - Foundations of Physics 29 (11):1785-1805.
    Quantum mechanics of a particle in an infinite square well under the influence of a time-dependent electric field is reconsidered. In some gauge, the Hamiltonian depends linearly on the momentum operator, which is symmetric but not self-adjoint when defined on a finite interval. In spite of this symmetric part, the Hamiltonian operator is shown to be self-adjoint. This follows from a theorem by Kato and Rellich which guarantees the stability of a self-adjoint operator under certain symmetric perturbations. (...)
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  18.  87
    From Permanence to Total Availability: A Quantum Conceptual Upgrade.Massimiliano Sassoli de Bianchi - 2012 - Foundations of Science 17 (3):223-244.
    We consider the classical concept of time of permanence and observe that its quantum equivalent is described by a bona fide self-adjoint operator. Its interpretation, by means of the spectral theorem, reveals that we have to abandon not only the idea that quantum entities would be characterizable in terms of spatial trajectories but, more generally, that they would possess the very attribute of spatiality. Consequently, a permanence time shouldn’t be interpreted as a “time” in quantum mechanics, but as a (...)
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  19.  22
    Mean and Variance in Quantum Theory.John E. Gray & Andrew Vogt - 2015 - Foundations of Physics 45 (8):883-888.
    Calculation of the mean of an observable in quantum mechanics is typically assumed to require that the state vector be in the domain of the corresponding self-adjoint operator or for a mixed state that the operator times the density matrix be in the trace class. We remind the reader that these assumptions are unnecessary. We state what is actually needed to calculate the mean of an observable as well as its variance.
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  20.  4
    The pragmatic QFT measurement problem and the need for a Heisenberg-like cut in QFT.Daniel Grimmer - 2023 - Synthese 202 (4):1-45.
    Despite quantum theory’s remarkable success at predicting the statistical results of experiments, many philosophers worry that it nonetheless lacks some crucial connection between theory and experiment. Such worries constitute the Quantum Measurement Problems. One can broadly identify two kinds of worries: (1) pragmatic: it is unclear how to model our measurement processes in order to extract experimental predictions, and (2) realist: we lack a satisfying metaphysical account of measurement processes. While both issues deserve attention, the pragmatic worries have worse consequences (...)
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  21.  57
    Time-energy uncertainty and relativistic canonical commutation relations in quantum spacetime.Eduard Prugovečki - 1982 - Foundations of Physics 12 (6):555-564.
    It is shown that the time operatorQ 0 appearing in the realization of the RCCR's [Qμ,Pv]=−jhgμv, on Minkowski quantum spacetime is a self adjoint operator on Hilbert space of square integrable functions over Σ m =σ×v m , where σ is a timelike hyperplane. This result leads to time-energy uncertainty relations that match their space-momentum counterparts. The operators Qμ appearing in Born's metric operator in quantum spacetime emerge as internal spacetime operators for exciton states, and the condition that (...)
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  22.  8
    Coordinate formalism on Hilbert manifolds: String bases of eigenvectors.Alexey Kryukov - unknown
    Coordinate formalism on Hilbert manifolds developed in \cite{Kryukov}, \cite{Kryukov1} is further analyzed. The main subject here is a comparison of the ordinary and the string bases of eigenvectors of a linear operator as introduced in \cite{Kryukov}. It is shown that the string basis of eigenvectors is a natural generalization of its classical counterpart. It is also shown that the developed formalism forces us to consider any Hermitian operator with continuous spectrum as a restriction to a space of square (...)
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  23.  34
    The Quantum Logic of Direct-Sum Decompositions: The Dual to the Quantum Logic of Subspaces.David Ellerman - 2018 - Logic Journal of the IGPL 26 (1):1-13.
    ince the pioneering work of Birkhoff and von Neumann, quantum logic has been interpreted as the logic of subspaces of a Hilbert space. There is a progression from the usual Boolean logic of subsets to the "quantum logic" of subspaces of a general vector space--which is then specialized to the closed subspaces of a Hilbert space. But there is a "dual" progression. The set notion of a partition is dual to the notion of a subset. Hence the Boolean logic of (...)
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  24.  47
    Unreal observables.Bryan W. Roberts - 2017 - Philosophy of Science 84 (5):1265-1274.
    This note argues that quantum observables can include not just self-adjoint operators, but any member of the class of normal operators, including those with non-real eigenvalues. Concrete experiments, statistics, and symmetries are all expressed in this more general context. However, this more general class of observables also introduces a new restriction on which sets of operators can be interpreted as observables at once. These sets are referred to here as 'sharp sets.
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  25.  36
    Torsion Fields, Cartan–Weyl Space–Time and State-Space Quantum Geometries, their Brownian Motions, and the Time Variables.Diego L. Rapoport - 2007 - Foundations of Physics 37 (4-5):813-854.
    We review the relation between spacetime geometries with trace-torsion fields, the so-called Riemann–Cartan–Weyl (RCW) geometries, and their associated Brownian motions. In this setting, the drift vector field is the metric conjugate of the trace-torsion one-form, and the laplacian defined by the RCW connection is the differential generator of the Brownian motions. We extend this to the state-space of non-relativistic quantum mechanics and discuss the relation between a non-canonical quantum RCW geometry in state-space associated with the gradient of the quantum-mechanical expectation (...)
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  26.  30
    Convergence of observables on quantum logics.W. Tomé & S. Gudder - 1990 - Foundations of Physics 20 (4):417-434.
    We define two types of convergence for observables on a quantum logic which we call M-weak and uniform M-weak convergence. These convergence modes correspond to weak convergence of probability measures. They are motivated by the idea that two (in general unbounded) observables are “close” if bounded functions of them are “close.” We show that M-weak and uniform M-weak convergence generalize strong resolvent and norm resolvent convergence for self-adjoint operators on a Hilbert space. Also, these types of convergence strengthen the weak (...)
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  27.  15
    The Split of the Dirac Hamiltonian into Precisely Predictable Energy Components.H. O. Cordes - 2004 - Foundations of Physics 34 (8):1117-1153.
    We are dealing with the Dirac Hamiltonian H = H0 + V with no magnetic field and radially symmetric electrostatic potential V = V(r), preferably the Coulomb potential. While the observable H is precisely predictable, its components H0 (relativistic mass) and V (potential energy) are not. However they both possess precisely predictable approximations H0 ∼ and V∼ which approximate accurately if the particle is not near its nucleus. On the other hand, near 0, H0 and V are practically unpredictable, perhaps (...)
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  28. Empirical consequences of the scientific construction: The program of local hidden-variables theories in quantum mechanics. [REVIEW]Miguel Ferrero & Emilio Santos - 1997 - Foundations of Physics 27 (6):765-800.
    We claim that physics has been constructed because three “philosophical” principles have been respected, namely, realism, locality, and consistency. These principles lead to an interpretation of quantum mechanics (QM) in terms of local hidden-variables theories (LHV). In order to prove that LHV have not been refuted, we analyze the empirical proofs of Bell's inequalities and we argue that none is loophole-free. Then we propose a restricted QM that does not contain measurement postulates and that does not claim that all state (...)
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  29.  50
    Symmetry, Compact Closure and Dagger Compactness for Categories of Convex Operational Models.Howard Barnum, Ross Duncan & Alexander Wilce - 2013 - Journal of Philosophical Logic 42 (3):501-523.
    In the categorical approach to the foundations of quantum theory, one begins with a symmetric monoidal category, the objects of which represent physical systems, and the morphisms of which represent physical processes. Usually, this category is taken to be at least compact closed, and more often, dagger compact, enforcing a certain self-duality, whereby preparation processes (roughly, states) are interconvertible with processes of registration (roughly, measurement outcomes). This is in contrast to the more concrete “operational” approach, in which the states and (...)
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  30.  7
    \em Bohmian Mechanics: The Physics and Mathematics of Quantum Theory.Detlef Dürr & Stefan Teufel - 2009 - Springer.
    Bohmian Mechanics was formulated in 1952 by David Bohm as a complete theory of quantum phenomena based on a particle picture. It was promoted some decades later by John S. Bell, who, intrigued by the manifestly nonlocal structure of the theory, was led to his famous Bell's inequalities. Experimental tests of the inequalities verified that nature is indeed nonlocal. Bohmian mechanics has since then prospered as the straightforward completion of quantum mechanics. This book provides a systematic introduction to Bohmian mechanics (...)
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  31.  16
    Quantum Electrostatics, Gauss’s Law, and a Product Picture for Quantum Electrodynamics; or, the Temporal Gauge Revised.Bernard S. Kay - 2021 - Foundations of Physics 52 (1):1-61.
    We provide a suitable theoretical foundation for the notion of the quantum coherent state which describes the electrostatic field due to a static external macroscopic charge distribution introduced by the author in 1998 and use it to rederive the formulae obtained in 1998 for the inner product of a pair of such states. (We also correct an incorrect factor of 4π\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$4\pi$$\end{document} in some of those formulae.) Contrary to what one might expect, (...)
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  32. Strict Constructivism and the Philosophy of Mathematics.Feng Ye - 2000 - Dissertation, Princeton University
    The dissertation studies the mathematical strength of strict constructivism, a finitistic fragment of Bishop's constructivism, and explores its implications in the philosophy of mathematics. ;It consists of two chapters and four appendixes. Chapter 1 presents strict constructivism, shows that it is within the spirit of finitism, and explains how to represent sets, functions and elementary calculus in strict constructivism. Appendix A proves that the essentials of Bishop and Bridges' book Constructive Analysis can be developed within strict constructivism. Appendix B further (...)
     
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  33.  45
    Observables, disassembled.Bryan W. Roberts - 2018 - Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics 63:150-162.
    How should we characterise the observable aspects of quantum theory? This paper argues that philosophers and physicists should jettison a standard dogma: that observables must be represented by self-adjoint or Hermitian operators. Four classes of non-standard observables are identified: normal operators, symmetric operators, real-spectrum operators, and none of these. The philosophical and physical implications of each are explored.
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  34.  9
    A New Version of the Aharonov–Bohm Effect.César R. de Oliveira & Renan G. Romano - 2020 - Foundations of Physics 50 (3):137-146.
    We propose a simple situation in which the magnetic Aharonov–Bohm potential influences the values of the deficiency indices of the initial Schrödinger operator, so determining whether the particle interacts with the solenoid or not. Even with the particle excluded from the magnetic field, the number of self-adjoint extensions of the initial Hamiltonian depends on the magnetic flux. This is a new point of view of the Aharonov–Bohm effect.
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  35.  28
    A first-order equation for spin in a manifestly relativistically covariant quantum theory.A. Arensburg & L. P. Horwitz - 1992 - Foundations of Physics 22 (8):1025-1039.
    Relativistic quantum mechanics has been formulated as a theory of the evolution ofevents in spacetime; the wave functions are square-integrable functions on the four-dimensional spacetime, parametrized by a universal invariant world time τ. The representation of states with spin is induced with a little group that is the subgroup of O(3, 1) leaving invariant a timelike vector nμ; a positive definite invariant scalar product, for which matrix elements of tensor operators are covariant, emerges from this construction. In a previous study (...)
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  36.  75
    Canonical Extensions and Relational Representations of Lattices with Negation.Agostinho Almeida - 2009 - Studia Logica 91 (2):171-199.
    This work is part of a wider investigation into lattice-structured algebras and associated dual representations obtained via the methodology of canonical extensions. To this end, here we study lattices, not necessarily distributive, with negation operations. We consider equational classes of lattices equipped with a negation operation ¬ which is dually self-adjoint (the pair (¬,¬) is a Galois connection) and other axioms are added so as to give classes of lattices in which the negation is De Morgan, orthonegation, antilogism, pseudocomplementation or (...)
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  37.  16
    Quantum Mechanics of the Supplementary Series.Andrzej Staruszkiewicz - 2002 - Foundations of Physics 32 (12):1863-1876.
    Unitary, irreducible representations of the proper, orthochronous Lorentz group comprise the main series and the supplementary series. The main series is spanned by the complete set of eigenstates of the self-adjoint Casimir operator C 1=−(1/2)M μν M μν , where M μν are generators of Lorentz transformations. The supplementary series has no such interpretation; moreover it is spurious from the point of view of functional analysis as it does not enter into the integral representation of an arbitrary test function. (...)
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  38.  13
    Hypo-EP Matrices of Adjointable Operators on Hilbert C ∗ -Modules.Xiaopeng Li, Junjie Huang & Alatancang Chen - 2021 - Complexity 2021:1-8.
    This paper introduces and studies hypo-EP matrices of adjointable operators on Hilbert C ∗ -modules, based on the generalized Schur complement. The necessary and sufficient conditions for some modular operator matrices to be hypo-EP are given, and some special circumstances are also analyzed. Furthermore, an application of the EP operator in operator equations is given.
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  39.  73
    Coordinate Formalism on Abstract Hilbert Space: Kinematics of a Quantum Measurement. [REVIEW]Alexey A. Kryukov - 2002 - Foundations of Physics 33 (3):407-443.
    Coordinate form of tensor algebra on an abstract (infinite-dimensional) Hilbert space is presented. The developed formalism permits one to naturally include the improper states in the apparatus of quantum theory. In the formalism the observables are represented by the self-adjoint extensions of Hermitian operators. The unitary operators become linear isometries. The unitary evolution and the non-unitary collapse processes are interpreted as isometric functional transformations. Several experiments are analyzed in the new context.
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  40.  76
    Persistent operational synchrony within brain default-mode network and self-processing operations in healthy subjects.Andrew A. Fingelkurts & Alexander A. Fingelkurts - 2011 - Brain and Cognition 75 (2):79-90.
    Based on the theoretical analysis of self-consciousness concepts, we hypothesized that the spatio-temporal pattern of functional connectivity within the default-mode network (DMN) should persist unchanged across a variety of different cognitive tasks or acts, thus being task-unrelated. This supposition is in contrast with current understanding that DMN activated when the subjects are resting and deactivated during any attention-demanding cognitive tasks. To test our proposal, we used, in retrospect, the results from our two early studies ([Fingelkurts, 1998] and [Fingelkurts et al., (...)
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  41.  14
    Weak-operator Continuity and the Existence of Adjoints.Douglas Bridges & Luminita Dediu - 1999 - Mathematical Logic Quarterly 45 (2):203-206.
    It is shown, within constructive mathematics, that the unit ball B1 of the set of bounded operators on a Hilbert space H is weak-operator totally bounded. This result is then used to prove that the weak-operator continuity of the mapping T → AT on B1 is equivalent to the existence of the adjoint of A.
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  42.  17
    An algebraic theory of normal forms.Silvio Ghilardi - 1995 - Annals of Pure and Applied Logic 71 (3):189-245.
    In this paper we present a general theory of normal forms, based on a categorial result for the free monoid construction. We shall use the theory mainly for proposictional modal logic, although it seems to have a wider range of applications. We shall formally represent normal forms as combinatorial objects, basically labelled trees and forests. This geometric conceptualization is implicit in and our approach will extend it to other cases and make it more direct: operations of a purely geometric and (...)
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  43.  19
    Transparent unifiers in modal logics with self-conjugate operators.Wojciech Dzik - 2006 - Bulletin of the Section of Logic 35 (2/3):73-83.
  44.  15
    Young University Students’ Academic Self-Regulation Profiles and Their Associated Procrastination: Autonomous Functioning Requires Self-Regulated Operations.Rafael Valenzuela, Nuria Codina, Isabel Castillo & José Vicente Pestana - 2020 - Frontiers in Psychology 11.
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  45.  81
    Foreword.Donnie J. Self - 1986 - Theoretical Medicine and Bioethics 7 (1):5-6.
    On May 11th a round table discussion was held on the subject "The Interactions of Science and Art under the Conditions of the Revolution in Science and Technology ," organized by the editorial boards of the journals Voprosy filosofii and Voprosy literatury.
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  46.  41
    Modes of Adjointness.M. Menni & C. Smith - 2013 - Journal of Philosophical Logic (2-3):1-27.
    The fact that many modal operators are part of an adjunction is probably folklore since the discovery of adjunctions. On the other hand, the natural idea of a minimal propositional calculus extended with a pair of adjoint operators seems to have been formulated only very recently. This recent research, mainly motivated by applications in computer science, concentrates on technical issues related to the calculi and not on the significance of adjunctions in modal logic. It then seems a worthy enterprise (both (...)
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  47. Self-control, co-operation, and intention's authority.Lilian O'Brien - 2020 - In Alfred Mele (ed.), Surrounding Self-Control. Oxford University Press, Usa.
    In this chapter I defend a novel view of the relationships among intention for the future, self-control, and co-operation. I argue that when an agent forms an intention for the future she comes to regard herself as criticizable if she does not act in accordance with her intention and as praiseworthy if she does. In forming intentions, then, agents acquire dispositions to have reflexive evaluative attitudes. In contexts where the agent has inclinations that run contrary to her unrescinded intention, these (...)
     
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  48.  92
    Partiality and Adjointness in Modal Logic.Wesley H. Holliday - 2014 - In Rajeev Goré, Barteld Kooi & Agi Kurucz (eds.), Advances in Modal Logic, Vol. 10. College Publications. pp. 313-332.
    Following a proposal of Humberstone, this paper studies a semantics for modal logic based on partial “possibilities” rather than total “worlds.” There are a number of reasons, philosophical and mathematical, to find this alternative semantics attractive. Here we focus on the construction of possibility models with a finitary flavor. Our main completeness result shows that for a number of standard modal logics, we can build a canonical possibility model, wherein every logically consistent formula is satisfied, by simply taking each individual (...)
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  49. Operational pointer semantics: Solution to self-referential puzzles I.Haim Gaifman - 1988 - In M. Y. Vardi (ed.), Proceedings of the Second Conference on Theoretical Aspects of Reasoning About Knowledge. Morgan Kaufman. pp. 43–60.
     
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  50.  83
    The ‘Operational’ Definition of Self-Control.Marleen Gillebaart - 2018 - Frontiers in Psychology 9.
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