Related papers: On the energy density in quantum mechanics

On the energy density in quantum mechanics

URL: http://arxiv.org/abs/2306.15999v1
Date: Wed, 28 Jun 2023 08:19:56 GMT
Title: On the energy density in quantum mechanics
Authors: Francisco Torres Arvizu, Adrian Ortega, and Hern\'an Larralde
Abstract summary: We propose a way to probe a system by varying the size of a well containing a quantum particle. We show that the mean work done by moving the wall is closely related to one of the definitions for energy density.
Score: 0.0
License: http://creativecommons.org/licenses/by/4.0/
Abstract: There are several definitions of energy density in quantum mechanics. These yield expressions that differ locally, but all satisfy a continuity equation and integrate to the value of the expected energy of the system under consideration. Thus, the question of whether there are physical grounds to choose one definition over another arises naturally. In this work, we propose a way to probe a system by varying the size of a well containing a quantum particle. We show that the mean work done by moving the wall is closely related to one of the definitions for energy density. Specifically, the appropriate energy density, evaluated at the wall corresponds to the force exerted by the particle locally, against which the work is done. We show that this identification extends to two and three dimensional systems.

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