Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Science in China Series A-Mathematics Physics Astronomy & Technological Science

Classical Limit of Quantum Mechanics

Xiang-You Huang

Published Feb 20, 1993• 1 citation
Publisher

Abstract

Because of the use of different limiting procedures, there are two conflict conclusions on wave function. One is that a wave function can describe a single particle and the other is that it can only describe an ensemble in the classical limit. In this paper the limiting procedures have been compared. We put the synthesized limit n→∞, →0 but keep E(n, ) to be the actual measured value of energy. Under this limit condition, we can not only prove that a wave function can only describe an ensemble, but also can make clear the dynamical behavior of the particles of the ensemble. Calculations show that the reason why quantum mechanics cannot describe a particle is not because of the motion equation but because of the definition of state for the particle.

DOI
10.1360/ya1993-36-2-181

Related papers

What object does the wave function describe?

Yuri A. Rylov

It is shown that the wave function describes the state of the statistical ensemble E[S] of individual particles, or the statistical average particle . This result follows from the fact that in the classical limit h=0 the Schroedinger equation turns to the dynamic equations for the statistical ensemble of classical particles. The statement that the wave function describes the state of an individual particle is incompatible with the quantum mechanics formalism. It is shown that the statistical interpretation of quantum mechanics is a corollary of the fact, that the QM formalism is the technique of the statistical ensemble description, restricted by constraints of the dynamic equation linearity.

arXiv:physics/0405117•May 21, 2004•5 citations

Incompatibility of the Copenhagen interpretation with quantum formalism and its reasons

Yuri A. Rylov

It is proved the mathematical theorem, that the wave function describes the statistical ensemble of particles, but not a single particle. Supposition, that the wave function describes a single particle appears to be incompatible with formalism of quantum mechanics. One discusses the reasons, why this very simple statement has not been proved mathematically for many years. The reason lies in application of the trial and error methods for construction of the quantum mechanics. Application of this method as the main tool of investigation during eighty years generated ”fitting mentality ” of all microwold researchers. In this paper we prove a very important theorem, which claims that the wave function may not describe an individual quantum particle. It describes always a statistical ensemble of quantum particles. We shall show, that the action AS for the Schrödinger particle SS (the dynamic system described by the Schrödinger equation) turns into the action AE[Scl] for the statistical ensemble E [Scl] of free classical particles Scl, when the quantum constant � → 0. Such a transition is possible only in the case, when the wave function ψ describes a statistical ensemble of quantum particles, but not a single particle. For the free Schrödinger particle SS the action has the form

arXiv:physics/0604111•Apr 14, 2006•7 citations

On a Parallelism between Classical Mechanics and Quantum Mechanics

Yoshio Nishiyama

Striking parallelism between classical mechanics and quantum mechanics is evidenced for several bound system in a rather general form by introducing reasonably “quantum-mechanical momentum” from the Schrödinger equation. The following are proved: The “quantum-mechanical momentum” which is nearly equal to the corresponding classical momentum in “classical region” can be defined in the whole range of validity of the coordinate for the bound systems. In the same way as in classical mechanics, in quantum mechanics one can construct an associated wave accompanying a motion of a quantum particle and obeying the Schrödinger equation. The uniqueness condition on the associated wave throughout an orbit leads to the boundary condition on the wave function which is composed of the associated wave and to “quantum-mechanical quantization condition”, equivalently. In addition, all these quantum-mechanical quantities are approximately equal to the corresponding classical ones in the “classical region” of the coordinate. In particular it is demonstrated that even for a bound system of a singular (central) potential exists the ground state with the lowest energy eigenvalue. It is proved in one dimension that to any physical system obeying the Schrödinger equation always exists the corresponding classical system.

Progress of Theoretical Physics•Aug 1, 1965•0 citations

A DISCUSSION ABOUT THE PAPER “DETERMINISTIC PROPERTIES CONTAINER IN QUANTUM SYSTEMS WITH CONTINUOUS SPECTRUM”

LIANG FANG-HAO, 山东大学数学系,济南250100

For a single particle system with continuous energy spectrum, the paper “Deterministic Properties Contained in Quantum Systems with Continuous Spectrum” uses the “double wave functions” to describe the quantum behavior of each particle in the ensemble staying in an energy eigenstate. And the “equivalence theorem” in the paper points out that the double wave description will become the classical mechanics description in the classical limit. However, the statistical distribution of results of measurement of a physical quantity predicted by the double wave description for the ensemble is very different from that predicted by the usual quantum mechanics. And the proof given in the paper for the “equivalence theorem” is incorrect. Actually, this theorem is not true.

Acta Physica Sinica•Jan 1, 2001•0 citations

Correspondence between quantum and classical descriptions for free particles

Xin Huang

We define the condition of the quasiclassical state of free particles, which is useful in the approximate treatment of quantum systems. Then we introduce classical pure ensembles. Their states are represented using distribution functions on phase space. We compare distribution functions of classical pure ensembles and Wigner distribution functions of quasiclassical states for free particles and draw two conclusions: (i) A wave function does not describe an individual particle but a classical pure ensemble. (ii) Given a quasiclassical wave function, we can tell which classical pure ensemble is described by it.

Physical Review A•Aug 21, 2008•9 citations

Wave mechanics

Vladimir Mitin, Viatcheslav A. Kochelap, Michael A. Stroscio

Introduction In this chapter we discuss the basic physical concepts and equations related to the behavior of particles in the nanoworld. We introduce the Schrödinger wave equation for particles and determine the ways to calculate observable physical quantities. We find that, in wave mechanics, the motion of a particle confined to a finite volume is always characterized by discrete values of the energy and standing-wave-like wavefunctions, i.e., such a motion is quantized. While motion in an infinite space (i.e., free motion) is not quantized and is described by propagating waves, the energy of the particle is characterized by a continuous range of values. Keeping in mind the diverse variants of nanostructures, by using wave mechanics we analyze some particular examples, which highlight important quantum properties of particles. Many of the examples analyzed can serve as the simplest models of nanostructures and will be exploited in following chapters to understand the fundamentals of processes in nanoelectronics. The Schrödinger wave equation From the previous chapter, we conclude that nanosize physical systems are quantum-mechanical systems, inasmuch as their sizes are comparable to typical de Broglie wavelengths of the particles composing these systems. In dealing with quantum-mechanical systems, one aims at determining the wavefunction of a single particle or of the whole system. As we will demonstrate in the subsequent discussion, knowledge of the wavefunction in quantum mechanics is sufficient to describe completely a particle or even a system of particles.

Cambridge University Press eBooks•Dec 6, 2007•0 citations
Because of the use of different limiting procedures, there are two conflict conclusions on wave function. One is that a wave function can describe a single particle and the other is that it can only describe an ensemble in the classical limit. In this paper the limiting procedures have been compared. We put the synthesized limit n→∞, →0 but keep E(n, ) to be the actual measured value of energy. Under this limit condition, we can not only prove that a wave function can only describe an ensemble, but also can make clear the dynamical behavior of the particles of the ensemble. Calculations show that the reason why quantum mechanics cannot describe a particle is not because of the motion equation but because of the definition of state for the particle.
It is shown that the wave function describes the state of the statistical ensemble E[S] of individual particles, or the statistical average particle . This result follows from the fact that in the classical limit h=0 the Schroedinger equation turns to the dynamic equations for the statistical ensemble of classical particles. The statement that the wave function describes the state of an individual particle is incompatible with the quantum mechanics formalism. It is shown that the statistical interpretation of quantum mechanics is a corollary of the fact, that the QM formalism is the technique of the statistical ensemble description, restricted by constraints of the dynamic equation linearity.
It is proved the mathematical theorem, that the wave function describes the statistical ensemble of particles, but not a single particle. Supposition, that the wave function describes a single particle appears to be incompatible with formalism of quantum mechanics. One discusses the reasons, why this very simple statement has not been proved mathematically for many years. The reason lies in application of the trial and error methods for construction of the quantum mechanics. Application of this method as the main tool of investigation during eighty years generated ”fitting mentality ” of all microwold researchers. In this paper we prove a very important theorem, which claims that the wave function may not describe an individual quantum particle. It describes always a statistical ensemble of quantum particles. We shall show, that the action AS for the Schrödinger particle SS (the dynamic system described by the Schrödinger equation) turns into the action AE[Scl] for the statistical ensemble E [Scl] of free classical particles Scl, when the quantum constant � → 0. Such a transition is possible only in the case, when the wave function ψ describes a statistical ensemble of quantum particles, but not a single particle. For the free Schrödinger particle SS the action has the form
Striking parallelism between classical mechanics and quantum mechanics is evidenced for several bound system in a rather general form by introducing reasonably “quantum-mechanical momentum” from the Schrödinger equation. The following are proved: The “quantum-mechanical momentum” which is nearly equal to the corresponding classical momentum in “classical region” can be defined in the whole range of validity of the coordinate for the bound systems. In the same way as in classical mechanics, in quantum mechanics one can construct an associated wave accompanying a motion of a quantum particle and obeying the Schrödinger equation. The uniqueness condition on the associated wave throughout an orbit leads to the boundary condition on the wave function which is composed of the associated wave and to “quantum-mechanical quantization condition”, equivalently. In addition, all these quantum-mechanical quantities are approximately equal to the corresponding classical ones in the “classical region” of the coordinate. In particular it is demonstrated that even for a bound system of a singular (central) potential exists the ground state with the lowest energy eigenvalue. It is proved in one dimension that to any physical system obeying the Schrödinger equation always exists the corresponding classical system.
For a single particle system with continuous energy spectrum, the paper “Deterministic Properties Contained in Quantum Systems with Continuous Spectrum” uses the “double wave functions” to describe the quantum behavior of each particle in the ensemble staying in an energy eigenstate. And the “equivalence theorem” in the paper points out that the double wave description will become the classical mechanics description in the classical limit. However, the statistical distribution of results of measurement of a physical quantity predicted by the double wave description for the ensemble is very different from that predicted by the usual quantum mechanics. And the proof given in the paper for the “equivalence theorem” is incorrect. Actually, this theorem is not true.
We define the condition of the quasiclassical state of free particles, which is useful in the approximate treatment of quantum systems. Then we introduce classical pure ensembles. Their states are represented using distribution functions on phase space. We compare distribution functions of classical pure ensembles and Wigner distribution functions of quasiclassical states for free particles and draw two conclusions: (i) A wave function does not describe an individual particle but a classical pure ensemble. (ii) Given a quasiclassical wave function, we can tell which classical pure ensemble is described by it.
Introduction In this chapter we discuss the basic physical concepts and equations related to the behavior of particles in the nanoworld. We introduce the Schrödinger wave equation for particles and determine the ways to calculate observable physical quantities. We find that, in wave mechanics, the motion of a particle confined to a finite volume is always characterized by discrete values of the energy and standing-wave-like wavefunctions, i.e., such a motion is quantized. While motion in an infinite space (i.e., free motion) is not quantized and is described by propagating waves, the energy of the particle is characterized by a continuous range of values. Keeping in mind the diverse variants of nanostructures, by using wave mechanics we analyze some particular examples, which highlight important quantum properties of particles. Many of the examples analyzed can serve as the simplest models of nanostructures and will be exploited in following chapters to understand the fundamentals of processes in nanoelectronics. The Schrödinger wave equation From the previous chapter, we conclude that nanosize physical systems are quantum-mechanical systems, inasmuch as their sizes are comparable to typical de Broglie wavelengths of the particles composing these systems. In dealing with quantum-mechanical systems, one aims at determining the wavefunction of a single particle or of the whole system. As we will demonstrate in the subsequent discussion, knowledge of the wavefunction in quantum mechanics is sufficient to describe completely a particle or even a system of particles.