Results for 'generalized Dirac operators'

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  1.  59
    Cartan–Weyl Dirac and Laplacian Operators, Brownian Motions: The Quantum Potential and Scalar Curvature, Maxwell’s and Dirac-Hestenes Equations, and Supersymmetric Systems. [REVIEW]Diego L. Rapoport - 2005 - Foundations of Physics 35 (8):1383-1431.
    We present the Dirac and Laplacian operators on Clifford bundles over space–time, associated to metric compatible linear connections of Cartan–Weyl, with trace-torsion, Q. In the case of nondegenerate metrics, we obtain a theory of generalized Brownian motions whose drift is the metric conjugate of Q. We give the constitutive equations for Q. We find that it contains Maxwell’s equations, characterized by two potentials, an harmonic one which has a zero field (Bohm-Aharonov potential) and a coexact term that (...)
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  2. Reformulation of Dirac’s theory of electron to avoid negative energy or negative time solution.Biswaranjan Dikshit - 2017 - Journal of Theoretical Physics and Cryptography 13:1-4.
    Dirac’s relativistic theory of electron generally results in two possible solutions, one with positive energy and other with negative energy. Although positive energy solutions accurately represented particles such as electrons, interpretation of negative energy solution became very much controversial in the last century. By assuming the vacuum to be completely filled with a sea of negative energy electrons, Dirac tried to avoid natural transition of electron from positive to negative energy state using Pauli’s exclusion principle. However, many scientists (...)
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  3.  29
    Operator calculus: the lost formulation of quantum mechanics.Gonzalo Gimeno, Mercedes Xipell & Marià Baig - 2020 - Archive for History of Exact Sciences 75 (3):283-322.
    Traditionally, “the operator calculus of Born and Wiener” has been considered one of the four formulations of quantum mechanics that existed in 1926. The present paper reviews the operator calculus as applied by Max Born and Norbert Wiener during the last months of 1925 and the early months of 1926 and its connections with the rise of the new quantum theory. Despite the relevance of this operator calculus, Born–Wiener’s joint contribution to the topic is generally bypassed in historical accounts of (...)
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  4.  20
    The Generalized Representation of Particle Localization in Quantum Mechanics.G. F. Melloy - 2002 - Foundations of Physics 32 (4):503-530.
    It has been shown earlier that while strict localization of the free Dirac particle is not describable within the usual mathematical formalism, it is possible to describe sequences of positive-energy states whose spread Δ x =〈(x−x 0)2〉 about any given point x 0 approaches zero, where x is Dirac's position operator. The concept of a generalized function is extended here to allow for the succinct description of localized states in terms of “Asymptotic Localizing Functions.” Localization of both (...)
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  5.  65
    General covariance and the objectivity of space-time point-events: The physical role of gravitational and gauge degrees of freedom - DRAFT.Luca Lusanna & Massimo Pauri - unknown
    This paper deals with a number of technical achievements that are instrumental for a dis-solution of the so-called "Hole Argument" in general relativity. Such achievements include: 1) the analysis of the "Hole" phenomenology in strict connection with the Hamiltonian treatment of the initial value problem. The work is carried through in metric gravity for the class of Christoudoulou-Klainermann space-times, in which the temporal evolution is ruled by the "weak" ADM energy; 2) a re-interpretation of "active" diffeomorphisms as "passive and metric-dependent" (...)
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  6.  87
    Generalized Dirac Equation with Induced Energy-Dependent Potential via Simple Similarity Transformation and Asymptotic Iteration Methods.T. Barakat & H. A. Alhendi - 2013 - Foundations of Physics 43 (10):1171-1181.
    This study shows how precise simple analytical solutions for the generalized Dirac equation with repulsive vector and attractive energy-dependent Lorentz scalar potentials, position-dependent mass potential, and a tensor interaction term can be obtained within the framework of both similarity transformation and the asymptotic iteration methods. These methods yield a significant improvement over existing approaches and provide more plausible and applicable ways in explaining the pseudospin symmetry’s breaking mechanism in nuclei.
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  7. Generalized logical operations among conditional events.Angelo Gilio & Giuseppe Sanfilippo - 2019 - Applied Intelligence 49:79-102.
    We generalize, by a progressive procedure, the notions of conjunction and disjunction of two conditional events to the case of n conditional events. In our coherence-based approach, conjunctions and disjunctions are suitable conditional random quantities. We define the notion of negation, by verifying De Morgan’s Laws. We also show that conjunction and disjunction satisfy the associative and commutative properties, and a monotonicity property. Then, we give some results on coherence of prevision assessments for some families of compounded conditionals; in particular (...)
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  8.  82
    Generalized distributivity operators.Peter Lasersohn - 1998 - Linguistics and Philosophy 21 (1):83-93.
    Presents a series of generalizations of distributivity operators across a type hierarchy, in order to account for collective-distributive ambiguities for non-subject arguments.
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  9.  11
    Energy levels of the hydrogen atom due to a generalized Dirac equation.Ulrich Bleyer - 1993 - Foundations of Physics 23 (7):1025-1048.
    The consequences of a generalized Dirac equation are discussed for the energy levels of the hydrogen atom. Apart from the usual generalizations of the Dirac equation by adding new interaction terms, we generalize the anticommutation rule of the Dirac matrices, which leads to spin-dependent propagation properties. Such a theory can be looked at as a model theory for testing Lorentz invariance or as an outcome of pregeometric dynamical induction schemes for space-time structure.For special examples of (...) Dirac matrices including perturbation terms with respect to the SRT Dirac matrices, we derive the energy level of the hydrogen atom and find a hyperfine splitting due to these perturbations. A comparison of this additional splitting with Lamb shift measurements gives us upper limits for possible perturbations, which turn out to be of measurable magnitude. Spin precession experiments give much more restrictive limits. So, it turns out that the hydrogen atom is not such a sensitive indicator for the Lorentz invariance as widely believed. (shrink)
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  10. Generalization of operant and respondent keypecks.Sj Weiss & Rd Weissman - 1990 - Bulletin of the Psychonomic Society 28 (6):483-484.
     
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  11.  77
    Mind your p's and q's: Von Neumann versus Jordan on the Foundations of Quantum Theory.Anthony Duncan & Michel Janssen - unknown
    In early 1927, Pascual Jordan published his version of what came to be known as the Dirac-Jordan statistical transformation theory. Later that year and partly in response to Jordan, John von Neumann published the modern Hilbert space formalism of quantum mechanics. Central to both formalisms are expressions for conditional probabilities of finding some value for one quantity given the value of another. Beyond that Jordan and von Neumann had very different views about the appropriate formulation of problems in the (...)
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  12.  20
    Domain General Sequence Operations Contribute to Pre-SMA Involvement in Visuo-spatial Processing.E. Charles Leek, Kenneth S. L. Yuen & Stephen J. Johnston - 2016 - Frontiers in Human Neuroscience 10.
  13.  7
    On a generalized inference operation.Marek Nowak & Piotr Rydzewski - 1990 - Acta Universitatis Lodziensis. Folia Philosophica. Ethica-Aesthetica-Practica 7:105-110.
    Celem pracy jest analiza formalna pewnych ogólnych własności charakteryzujących wnioskowania. Autorzy twierdzą, że posiadanie tych własności jest warunkiem koniecznym, aby wnioskowanie było logicznie wartościowe. Wprowadzają aksjomatycznie pojęcie "uogólnionej operacji inferencji", które formalnie ujmuje wnioskowanie mające owe cechy. Następnie reprezentują uogólnioną operację inferencji przy użyciu relacji binarnych określonych na podzbiorach języka. Podają również taką reprezentację dla logicznej operacji konsekwencji (każda logiczna operacja konsekwencji jest uogólnioną operacją inferencji).
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  14.  57
    Spinor Matter in a Gravitational Field: Covariant Equations à la Heisenberg. [REVIEW]James P. Crawford - 1998 - Foundations of Physics 28 (3):457-470.
    A fundamental tenet of general relativity is geodesic motion of point particles. For extended objects, however, tidal forces make the trajectories deviate from geodesic form. In fact Mathisson, Papapetrou, and others have found that even in the limit of very small size there exists a residual curvature-spin force. Another important physical case is that of field theory. Here the ray (WKB) approximation may be used to obtain the equation of motion. In this article I consider an alternative procedure, the proper (...)
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  15.  49
    Quantisation, Representation and Reduction; How Should We Interpret the Quantum Hamiltonian Constraints of Canonical Gravity?Karim P. Y. Thébault - unknown
    Hamiltonian constraints feature in the canonical formulation of general relativity. Unlike typical constraints they cannot be associated with a reduction procedure leading to a non-trivial reduced phase space and this means the physical interpretation of their quantum analogues is ambiguous. In particular, can we assume that “quantisation commutes with reduction” and treat the promotion of these constraints to operators annihilating the wave function, according to a Dirac type procedure, as leading to a Hilbert space equivalent to that reached (...)
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  16. Maximal beable subalgebras of quantum-mechanical observables.Hans Halvorson & Rob Clifton - 1999 - International Journal of Theoretical Physics 38:2441-2484.
    The centerpiece of Jeffrey Bub's book Interpreting the Quantum World is a theorem (Bub and Clifton 1996) which correlates each member of a large class of no-collapse interpretations with some 'privileged observable'. In particular, the Bub-Clifton theorem determines the unique maximal sublattice L(R,e) of propositions such that (a) elements of L(R,e) can be simultaneously determinate in state e, (b) L(R,e) contains the spectral projections of the privileged observable R, and (c) L(R,e) is picked out by R and e alone. In (...)
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  17.  22
    Currents in a theory of strong interaction based on a fiber bundle geometry.W. Drechsler - 1977 - Foundations of Physics 7 (9-10):629-671.
    A fiber bundle constructed over spacetime is used as the basic underlying framework for a differential geometric description of extended hadrons. The bundle has a Cartan connection and possesses the de Sitter groupSO(4, 1) as structural group, operating as a group of motion in a locally defined space of constant curvature (the fiber) characterized by a radius of curvatureR≈10−13 cm related to the strong interactions. A hadronic matter field ω(x, ζ) is defined on the bundle space, withx the spacetime coordinate (...)
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  18. The role of consciousness as meaning Maker in science, culture, and religion.Patrick A. Heelan - 2009 - Zygon 44 (2):467-486.
    Two hundred years ago, Friedrich Schleiermacher took critical issue with Immanuel Kant's intellectual notion of intuition as applied to human nature (Wellmon 2006). He found it necessary to modify—"hermeneutically," as he said—Kant's notion of anthropology by enabling it to include as human the new and strange human tribes Captain Cook found in the Pacific South Seas. A similar hermeneutic move is necessary if physics is to include the local contextual empirical syntheses of relativity and quantum physics. In this hermeneutical revision (...)
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  19.  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 (...)
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  20.  26
    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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  21.  79
    From quantum mechanics to universal structures of conceptualization and feedback on quantum mechanics.Mioara Mugur-Schächter - 1993 - Foundations of Physics 23 (1):37-122.
    In previous works we have established that the spacetime probabilistic organization of the quantum theory is determined by the spacetime characteristics of the operations by which the observer produces the objects to be studied (“states” of microsystems) and obtains qualifications of these. Guided by this first conclusion, we have then built a “general syntax of relativized conceptualization” where any description is explicitly and systematically referred to the two basic epistemic operations by which the conceptor introduces the object to be qualified (...)
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  22. Information, entropy and inductive logic.S. Pakswer - 1954 - Philosophy of Science 21 (3):254-259.
    It has been shown by several authors that in operations involving information a quantity appears which is the negative of the quantity usually defined as entropy in similar situations. This quantity ℜ = − KI has been termed “negentropy” and it has been shown that the negentropy of information and the physical entropy S are mirrorlike representations of the same train of events. In physical terminology the energy is degraded by an increase in entropy due to an increased randomness in (...)
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  23.  5
    Problems of Atomic Dynamics.Max Born - 1970 - MIT Press.
    In 1925-26, the late Max Born gave two sets of lectures at M.I.T., one on the structure of the atom, the other on the lattice theory of rigid bodies. Problems of Atomic Dynamics contains the text of both sets.What gives this volume its remarkable interest is just those dates: 1925-26. This must have been, by all accounts, the headiest period in twentieth-century physics, and Max Born was one of the leaders of the ferment. As Norbert Wiener remembers, "When Professor Born (...)
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  24.  24
    Multiple criteria decision making method based on normal interval-valued intuitionistic fuzzy generalized aggregation operator.Peide Liu & Fei Teng - 2016 - Complexity 21 (5):20-30.
  25.  39
    Multiple criteria decision making method based on normal interval-valued intuitionistic fuzzy generalized aggregation operator.Peide Liu & Fei Teng - 2016 - Complexity 21 (5):277-290.
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  26.  26
    The Stationary Dirac Equation as a Generalized Pauli Equation for Two Quasiparticles.Nikolay L. Chuprikov - 2015 - Foundations of Physics 45 (6):644-656.
    By analyzing the Dirac equation with static electric and magnetic fields it is shown that Dirac’s theory is nothing but a generalized one-particle quantum theory compatible with the special theory of relativity. This equation describes a quantum dynamics of a single relativistic fermion, and its solution is reduced to solution of the generalized Pauli equation for two quasiparticles which move in the Euclidean space with their effective masses holding information about the Lorentzian symmetry of the four-dimensional (...)
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  27.  25
    On generalized electromagnetism and Dirac algebra.David Fryberger - 1989 - Foundations of Physics 19 (2):125-159.
    Using a framework of Dirac algebra, the Clifford algebra appropriate for Minkowski space-time, the formulation of classical electromagnetism including both electric and magnetic charge is explored. Employing the two-potential approach of Cabibbo and Ferrari, a Lagrangian is obtained that is dyality invariant and from which it is possible to derive by Hamilton's principle both the symmetrized Maxwell's equations and the equations of motion for both electrically and magnetically charged particles. This latter result is achieved by defining the variation of (...)
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  28.  30
    Description of Composite Quantum Systems by Means of Classical Random Fields.Andrei Khrennikov - 2010 - Foundations of Physics 40 (8):1051-1064.
    Recently a new attempt to go beyond QM was performed in the form of so-called prequantum classical statistical field theory (PCSFT). In this approach quantum systems are described by classical random fields, e.g., the electron field or the neutron field. Averages of quantum observables arise as approximations of averages of classical variables (functionals of “prequantum fields”) with respect to fluctuations of fields. For classical variables given by quadratic functionals of fields, quantum and prequantum averages simply coincide. In this paper we (...)
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  29.  25
    Improving the quality of general surgical operation notes in accordance with the Royal College of Surgeons guidelines: a prospective completed audit loop study.Rahul Singh, Robert Chauhan & Suhail Anwar - 2012 - Journal of Evaluation in Clinical Practice 18 (3):578-580.
  30.  32
    Dirac brackets for general relativity on a null cone.Joshua N. Goldberg - 1985 - Foundations of Physics 15 (4):439-450.
    The Hamiltonian for the Einstein equations is constructed on a outgoing null cone with the help of the usual null tetrad. The resulting null surface constraints are shown to be second class in the terminology of Dirac. These second class constraints are eliminated by use of the “starring” procedure of Bergmann and Komar.
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  31.  23
    A generalization of Dirac nonlinear electrodynamics, and spinning charged particles.Waldyr A. Rodrigues, Jayme Vaz & Erasmo Recami - 1993 - Foundations of Physics 23 (3):469-485.
    In this paper—dedicated to Prof. Asim O. Barut—we generalize the Diracnon-linear electrodynamics by introducing two potentials(namely, the vector potential A and the pseudo-vector potential γ5B of the electromagnetic theorywith charges and magnetic monopoles) and by imposing the pseudoscalar part of the product ωω* to be zero, with ω≡A+γ5B. We show that the field equations of such a theory possess a soliton-like solution which can representa priori a “charged particle,” since it is endowed with a Coulomb field plus the field of (...)
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  32.  28
    MPT versus: A manifestly covariant presentation of motion reversal and particle-antiparticle exchange. [REVIEW]O. Costa de Beauregard - 1982 - Foundations of Physics 12 (9):861-871.
    We show that particle-antiparticle exchange and covariant motion reversal are two physically different aspects of the same mathematical transformation, either in the prequantal relativistic equation of motion of a charged point particle, in the general scheme of second quantization, or in the spinning wave equations of Dirac and of Petiau-Duffin-Kemmer. While, classically, charge reversal and rest mass reversal are equivalent operations, in the wave mechanical case mass reversal must be supplemented by exchange of the two adjoint equations, implying ψ (...)
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  33.  18
    A General Type for Storage Operators.Karim Nour - 1995 - Mathematical Logic Quarterly 41 (4):505-514.
    In 1990, J.L. Krivine introduced the notion of storage operator to simulate, in $lambda$-calculus, the 'call by value' in a context of a 'call by name'. J.L. Krivine has shown that, using Gödel translation from classical into intuitionistic logic, we can find a simple type for storage operators in AF2 type system. In this present paper, we give a general type for storage operators in a slight extension of AF2. We give at the end (without proof) a generalization (...)
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  34.  33
    General Spin Dirac Equation.Golden Gadzirayi Nyambuya - 2009 - Apeiron: Studies in Infinite Nature 16 (4):516.
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  35.  14
    Logical metatheorems for accretive and (generalized) monotone set-valued operators.Nicholas Pischke - 2023 - Journal of Mathematical Logic 24 (2).
    Accretive and monotone operator theory are central branches of nonlinear functional analysis and constitute the abstract study of certain set-valued mappings between function spaces. This paper deals with the computational properties of these accretive and (generalized) monotone set-valued operators. In particular, we develop (and extend) for this field the theoretical framework of proof mining, a program in mathematical logic that seeks to extract computational information from prima facie “non-computational” proofs from the mainstream literature. To this end, we establish (...)
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  36.  89
    A general theory of abstraction operators.Neil Tennant - 2004 - Philosophical Quarterly 54 (214):105-133.
    I present a general theory of abstraction operators which treats them as variable-binding term- forming operators, and provides a reasonably uniform treatment for definite descriptions, set abstracts, natural number abstraction, and real number abstraction. This minimizing, extensional and relational theory reveals a striking similarity between definite descriptions and set abstracts, and provides a clear rationale for the claim that there is a logic of sets (which is ontologically non- committal). The theory also treats both natural and real numbers (...)
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  37.  23
    Generalizing classical and effective model theory in theories of operations and classes.Paolo Mancosu - 1991 - Annals of Pure and Applied Logic 52 (3):249-308.
    Mancosu, P., Generalizing classical and effective model theory in theories of operations and classes, Annas of Pure and Applied Logic 52 249-308 . In this paper I propose a family of theories of operations and classes with the aim of developing abstract versions of model-theoretic results. The systems are closely related to those introduced and already used by Feferman for developing his program of ‘explicit mathematics’. The theories in question are two-sorted, with one kind of variable for individuals and the (...)
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  38.  29
    General logic-systems and finite consequence operators.Robert A. Herrmann - 2007 - Logica Universalis 1 (1):201-208.
    . In this paper, the significance of using general logic-systems and finite consequence operators defined on non-organized languages is discussed. Results are established that show how properties of finite consequence operators are independent from language organization and that, in some cases, they depend only upon one simple language characteristic. For example, it is shown that there are infinitely many finite consequence operators defined on any non-organized infinite language L that cannot be generated from any finite logic-system. On (...)
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  39. Dirac’s Refined Unification of Quantum Mechanics and Special Relativity: An Intertheoretic Context.Rinat M. Nugayev - 2022 - Teorie Vědy / Theory of Science 44 (1):37-57.
    One of the key episodes of history of modern physics – Paul Dirac’s startling contrivance of the relativistic theory of the electron – is elicited in the context of lucid epistemological model of mature theory change. The peculiar character of Dirac’s synthesis of special relativity and quantum mechanics is revealed by comparison with Einstein’s sophisticated methodology of the General Relativity contrivance. The subtle structure of Dirac’s scientific research program and first and foremost the odd principles that put (...)
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  40.  56
    The General Form of the Operation in Wittgenstein's Tractatus.Göran Sundholm - 1992 - Grazer Philosophische Studien 42 (1):57-76.
    The paper offers an interpretation of thesis 6.01. The treatment touches upon variables, identity, elementary propositions, internal relations. Klammerausdrücke, and operations. Wittenstein's notations are found not to cover the particular form of definition by induction that is used at 6 and 6.01. It is concluded that Wittgenstein's ability to design of a formal system of logic does not match his outstanding logico-philosophical insight.
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  41.  6
    Structure, Operation, and Experience of Clinical Ethics Consultation 2007-2013: A Report from the Massachusetts General Hospital Optimum Care Committee. [REVIEW]Andrew M. Courtwright, Eric L. Krakauer, M. Cornelia Cremens, Alexandra Cist, Julia Bandini, Sharon Brackett, Kimberly Erler, Wendy Cadge & Ellen M. Robinson - 2017 - Journal of Clinical Ethics 28 (2):137-152.
    We describe the structure, operation, and experience of the Massachusetts General Hospital ethics committee, formally called the Edwin H. Cassem Optimum Care Committee, from January 2007 through December 2013. Founded in 1974 as one of the nation’s first hospital ethics committees, this committee has primarily focused on the optimum use of life-sustaining treatments. We outline specific sociodemographic and clinical characteristics of consult patients during this period, demographic differences between the adult inpatient population and patients for whom the ethics committee was (...)
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  42.  16
    Operational Restrictions in General Probabilistic Theories.Sergey N. Filippov, Stan Gudder, Teiko Heinosaari & Leevi Leppäjärvi - 2020 - Foundations of Physics 50 (8):850-876.
    The formalism of general probabilistic theories provides a universal paradigm that is suitable for describing various physical systems including classical and quantum ones as particular cases. Contrary to the usual no-restriction hypothesis, the set of accessible meters within a given theory can be limited for different reasons, and this raises a question of what restrictions on meters are operationally relevant. We argue that all operational restrictions must be closed under simulation, where the simulation scheme involves mixing and classical post-processing of (...)
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  43.  13
    A general account of selection: Biology, immunology, and behavior-Open Peer Commentary-Is operant selectionism coherent?D. L. Hull, R. E. Langman, S. S. Glenn, F. Tonneau & M. B. C. Sokolowski - 2001 - Behavioral and Brain Sciences 24 (3):558-558.
    Hull et al.'s analysis of operant behavior in terms of interaction and replication does not seem consistent with a genuine selection model. The putative replicators do not replicate, and the overall process is more reminiscent of directed mutation than of natural selection. General analogies between natural selection and operant reinforcement are too superficial to be of much scientific use.
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  44.  13
    The General Form of the Operation in Wittgenstein's Tractatus.Göran Sundholm - 1992 - Grazer Philosophische Studien 42 (1):57-76.
    The paper offers an interpretation of thesis 6.01. The treatment touches upon variables, identity, elementary propositions, internal relations. Klammerausdrücke, and operations. Wittenstein's notations are found not to cover the particular form of definition by induction that is used at 6 and 6.01. It is concluded that Wittgenstein's ability to design of a formal system of logic does not match his outstanding logico-philosophical insight.
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  45.  79
    Generalized plithogenic whole hypersoft set, PFHSS-Matrix, operators and applications as COVID-19 data structures.Shazia Rana, Muhammad Saeed, Madiha Qayyum & Florentin Smarandache - 2023 - Journal of Intelligent and Fuzzy Systems 44.
    This article is a preliminary draft for initiating and commencing a new pioneer dimension of expression. To deal with higher-dimensional data or information flowing in this modern era of information technology and artificial intelligence, some innovative super algebraic structures are essential to be formulated. In this paper, we have introduced such matrices that have multiple layers and clusters of layers to portray multi-dimensional data or massively dispersed information of the plithogenic universe made up of numerous subjects their attributes, and sub-attributes. (...)
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  46.  17
    The Lattice Structures of Approximation Operators Based on L-Fuzzy Generalized Neighborhood Systems.Qiao-Ling Song, Hu Zhao, Juan-Juan Zhang, A. A. Ramadan, Hong-Ying Zhang & Gui-Xiu Chen - 2021 - Complexity 2021:1-10.
    Following the idea of L -fuzzy generalized neighborhood systems as introduced by Zhao et al., we will give the join-complete lattice structures of lower and upper approximation operators based on L -fuzzy generalized neighborhood systems. In particular, as special approximation operators based on L -fuzzy generalized neighborhood systems, we will give the complete lattice structures of lower and upper approximation operators based on L -fuzzy relations. Furthermore, if L satisfies the double negative law, then (...)
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  47.  31
    Some general principles of operational analysis.P. W. Bridgman - 1945 - Psychological Review 52 (5):246-249.
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  48.  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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    “The language of Dirac’s theory of radiation”: the inception and initial reception of a tool for the quantum field theorist.Markus Ehberger - 2022 - Archive for History of Exact Sciences 76 (6):531-571.
    In 1927, Paul Dirac first explicitly introduced the idea that electrodynamical processes can be evaluated by decomposing them into virtual (modern terminology), energy non-conserving subprocesses. This mode of reasoning structured a lot of the perturbative evaluations of quantum electrodynamics during the 1930s. Although the physical picture connected to Feynman diagrams is no longer based on energy non-conserving transitions but on off-shell particles, emission and absorption subprocesses still remain their fundamental constituents. This article will access the introduction and the initial (...)
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    Generalized compactness of nonmonotonic inference operations.Heinrich Herre - 1995 - Journal of Applied Non-Classical Logics 5 (1):121-135.
    The aim of the present paper is to analyse compactness properties of nonmonotonic inference operations within the framework of model theory. For this purpose the concepts of a deductive frame and its semantical counterpart, a semantical frame are introduced. Compactness properties play a fundamental in the study of non-monotonic inference, and in the paper several new versions of compactness are studied.
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