English
Related papers

Related papers: Establishment of the conserved operators using var…

200 papers

We present a method for calculating expectation values of operators in terms of a corresponding c-function formalism which is not the Wigner--Weyl position-momentum phase-space, but another space. Here, the quantity representing the quantum…

Quantum Physics · Physics 2020-01-08 Jonathan S Ben-Benjamin , William G Unruh

Assume that A is a bounded selfadjoint operator in a Hilbert space H. Then, the variational principle is obtained for some functional. As an application of this principle, a variational principle for the electrical capacitance of a…

Mathematical Physics · Physics 2014-02-14 Alexander G. Ramm

In the paradigmatic example of quantum measurements, whenever one measures a system which starts in a superposition of two states of a conserved quantity, it jumps to one of the two states, implying different final values for the quantity…

Quantum Physics · Physics 2025-07-30 Daniel Collins , Sandu Popescu

We present a scheme to store unitary operators with self-inverse generators in quantum states and a general circuit to retrieve them with definite success probability. The continuous variable of the operator is stored in a single-qubit…

Quantum Physics · Physics 2009-11-07 Jaehyun Kim , Yongwook Cheong , Jae-Seung Lee , Soonchil Lee

Both classical and quantum mechanics assume that physical laws are invariant under changes in the way that the world is labeled. This Principle of Decompositional Equivalence is formalized, and shown to forbid finite experimental…

Quantum Physics · Physics 2010-04-22 Chris Fields

A C*-algebra formulation of Quantum Mechanics is derived from purely operational axioms in which the primary role is played by the "transformations" that the system undergoes in the course of an "experiment". The notion of the {\em adjoint}…

Quantum Physics · Physics 2007-05-23 Giacomo Mauro D'Ariano

Quantum physics can only make statistical predictions about possible measurement outcomes, and these predictions originate from an operator algebra that is fundamentally different from the conventional definition of probability as a…

Quantum Physics · Physics 2020-06-11 Holger F. Hofmann

The position operator (defined within the Schroedinger representation in the standard way) becomes meaningless when periodic boundary conditions are adopted for the wavefunction, as usual in condensed matter physics. We show how to define…

Materials Science · Physics 2009-10-30 R. Resta

It is shown that some operators in quantum mechanics have hidden structures that are unobservable in principle. These structures are based on a supersymmetric decomposition of the momentum operator, and a nonassociative decomposition of the…

Quantum Physics · Physics 2009-03-03 Vladimir Dzhunushaliev

The quantum-mechanical state vector is not directly observable even though it is the fundamental variable that appears in Schrodinger's equation. In conventional time-dependent perturbation theory, the state vector must be calculated before…

Quantum Physics · Physics 2009-11-07 J. D. Franson , Michelle M. Donegan

We define a new dynamical variable, the relative existence e, in terms of space and time. Taking it as a generalized positional coordinate, we show that for conservative systems the canonically conjugated momentum is identified as the…

Quantum Physics · Physics 2007-05-23 C. G. S. Costa

Conservation laws are discussed in conjunction with quantum-mechanical indeterminacies of the corresponding observables. The considered examples show that the connections between energy and its indeterminacy may be quite intricate. The…

General Physics · Physics 2022-09-15 Moses Fayngold

A general formlulation for discrete-time quantum mechanics, based on Feynman's method in ordinary quantum mechanics, is presented. It is shown that the ambiguities present in ordinary quantum mechanics (due to noncommutativity of the…

Quantum Physics · Physics 2015-06-26 M. Khorrami

Assuming that quantum states, including pure states, represent subjective degrees of belief rather than objective properties of systems, the question of what other elements of the quantum formalism must also be taken as subjective is…

Quantum Physics · Physics 2015-06-26 M. S. Leifer

This paper considers a generalization of the notion of quantum observables in ontological models of quantum mechanics. Within this framework it is possible to construct physical models where quantum noncommutativity can arise dynamically.…

Quantum Physics · Physics 2007-12-12 Tung Ten Yong

Deformation quantization produces families of mathematically equivalent quantization procedures from which one must select the physically meaningful ones. As a selection principle we propose that the procedure must allow enough `observable'…

Quantum Algebra · Mathematics 2007-05-23 Murray Gerstenhaber

The fundamental laws of physics can be derived from the requirement of invariance under suitable classes of transformations on the one hand, and from the need for a well-posed mathematical theory on the other hand. As a part of this…

High Energy Physics - Theory · Physics 2016-12-28 Giampiero Esposito

The choice of mathematical representation when describing physical systems is of great consequence, and this choice is usually determined by the properties of the problem at hand. Here we examine the little-known wave operator…

Quantum Physics · Physics 2024-01-26 Gerard McCaul , Dmitry V. Zhdanov , Denys I. Bondar

A quantum mechanical model for the systems consisting of interacting bodies is considered. The model takes into account the noncommutativity of the space and impulse operators and the correlation equations for the indeterminacy of these…

Nuclear Theory · Physics 2007-05-23 A. I. Steshenko

It is proved here that, as a consequence of the unitary quantum evolution, the expectation value of a properly defined quantum entropy operator (as opposed to the non-evolving von Neumann entropy) can only increase during non adiabatic…

Quantum Physics · Physics 2008-11-25 Michele Campisi