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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