Related papers: Energy Non-Conservation in Quantum Mechanics

Energy Non-Conservation in Quantum Mechanics

URL: http://arxiv.org/abs/2101.11052v2
Date: Thu, 22 Jul 2021 19:19:54 GMT
Title: Energy Non-Conservation in Quantum Mechanics
Authors: Sean M. Carroll and Jackie Lodman
Abstract summary: We study the conservation of energy, or lack thereof, when measurements are performed in quantum mechanics. In Everettian quantum theory, while the expectation value of the Hamiltonian is conserved for the wave function of the universe, it is not constant within individual worlds.
Score: 0.0
License: http://creativecommons.org/licenses/by-nc-sa/4.0/
Abstract: We study the conservation of energy, or lack thereof, when measurements are performed in quantum mechanics. The expectation value of the Hamiltonian of a system can clearly change when wave functions collapse in accordance with the standard textbook (Copenhagen) treatment of quantum measurement, but one might imagine that the change in energy is compensated by the measuring apparatus or environment. We show that this is not true; the change in the energy of a state after measurement can be arbitrarily large, independent of the physical measurement process. In Everettian quantum theory, while the expectation value of the Hamiltonian is conserved for the wave function of the universe (including all the branches), it is not constant within individual worlds. It should therefore be possible to experimentally measure violations of conservation of energy, and we suggest an experimental protocol for doing so.

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