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Related papers: Projection evolution in quantum mechanics

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The treatment of time in relativity does not conform to that in quantum theory. To resolve the discrepancy, a formalization of time is introduced in an accompanying paper, starting from the assumption that the treatment of time in physics…

Quantum Physics · Physics 2024-11-06 Per Östborn

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

Quantum measurement and quantum operation theory is developed here by taking the relational properties among quantum systems, instead of the independent properties of a quantum system, as the most fundamental elements. By studying how the…

Quantum Physics · Physics 2021-04-20 Jianhao M. Yang

A dynamical quantum model assigns an eigenstate to a specified observable even when no measurement is made, and gives a stochastic evolution rule for that eigenstate. Such a model yields a distribution over classical histories of a quantum…

Quantum Physics · Physics 2007-05-23 Scott Aaronson

The quantum mechanics description of a physical object stretched in space and stable in time from the relativistic space-time properties point of view, introduced in special theory of relativity, is considered and analysed. The mathematical…

Quantum Physics · Physics 2007-05-23 Andrey V. Novikov-Borodin

Quantum physics involves an ensemble of quantum systems, usually one thinks of a large ensemble of identical quantum systems at one single time. In single ion experiments one has a single quantum system at an ensemble of different times.…

Quantum Physics · Physics 2007-05-23 A. Bohm , H. Kaldass , S. Komy , W. P. Schleich

We introduce a simple quantum mechanical model in which time and space are discrete and periodic. These features avoid the complications related to continuous-spectrum operators and infinite-norm states. The model provides a tool for…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Mauricio Mondragon , Alejandro Perez , Carlo Rovelli

We examine the longstanding problem of introducing a time observable in Quantum Mechanics; using the formalism of positive-operator-valued measures we show how to define such an observable in a natural way and we discuss some consequences.

Quantum Physics · Physics 2009-10-30 Riccardo Giannitrapani

Three postulates are discussed: first that well-defined properties cannot be assigned to an isolated system, secondly that quantum unitary evolution is atemporal, and thirdly that some physical processes are never reversed. It is argued…

Quantum Physics · Physics 2009-11-13 Andrew M. Steane

This note starts with a recapitulation of what people call the ``Measurement Problem'' of Quantum Mechanics (QM). The dissipative nature of the quantum-mechanical time-evolution of averages of states over large ensembles of identical…

Quantum Physics · Physics 2026-03-27 Jürg Fröhlich , Alessandro Pizzo

We investigate quantum effects in the evolution of general systems. For studying such temporal quantum phenomena, it is paramount to have a rigorous concept and profound understanding of the classical dynamics in such a system in the first…

Quantum Physics · Physics 2020-06-02 J. Sperling , I. A. Walmsley

Quantum brownian motion is a fundamental model for a proper understanding of open quantum systems in different contexts such as chemistry, condensed matter physics, bio-physics and opto- mechamics. In this paper we propose a novel approach…

Quantum Physics · Physics 2017-05-31 Matteo Carlesso , Angelo Bassi

Quantum timeless approaches solve the problem of time by recovering the usual unitary evolution of quantum theory relative to a clock in a stationary quantum Universe. For some Hamiltonians of the Universe, such as those including an…

Quantum Physics · Physics 2026-04-14 Simone Rijavec

Understanding the emergence of the thermodynamic arrow of time in microscopic systems is of fundamental importance, particularly given that unitary evolution preserves time-reversal symmetry. While projective measurements introduce temporal…

We present a theory of discontinuous motion of particles in continuous space-time. We show that the simplest nonrelativistic evolution equation of such motion is just the Schroedinger equation in quantum mechanics. This strongly implies…

Quantum Physics · Physics 2007-05-23 Rui Qi

We describe the time evolution of quantum systems in a classical background space-time by means of a covariant derivative in an infinite dimensional vector bundle. The corresponding parallel transport operator along a timelike curve $\cC$…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Dirk Graudenz

We analyze the problem of one dimensional quantum particle falling in a constant gravitational field, also known as the {\it bouncing ball}, employing a semiclassical approach known as momentous effective quantum mechanics. In this…

Quantum Physics · Physics 2019-04-16 Guillermo Chacon-Acosta , Hector Hernandez-Hernandez , Mercedes Velazquez

A geometric construction of the arrival time in conventional quantum mechanics is presented. It is based on a careful mathematical analysis of different quantization procedures for classical observables as functions of positions and…

Quantum Physics · Physics 2023-06-14 Jerzy Kijowski

We examine several numerical techniques for the calculation of the dynamics of quantum systems. In particular, we single out an iterative method which is based on expanding the time evolution operator into a finite series of Chebyshev…

Strongly Correlated Electrons · Physics 2015-05-13 Holger Fehske , Jens Schleede , Gerald Schubert , Gerhard Wellein , Vladimir S. Filinov , Alan R. Bishop

In order to resolve the measurement problem of Quantum Mechanics, non-unitary time evolution has been derived from the unitarity of standard quantum formalism. New wave functions of free and non-free quantum systems follow from Schroedinger…

Quantum Physics · Physics 2007-05-23 Pradip Kumar Chatterjee