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Spatially Averaged Quantum Inequalities Do Not Exist in Four-Dimensional Spacetime

L. H. Ford·Adam D. Helfer·Thomas A. Roman
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Abstract

We construct a particular class of quantum states for a massless, minimally coupled free scalar field which are of the form of a superposition of the vacuum and multi-mode two-particle states. These states can exhibit local negative energy densities. Furthermore, they can produce an arbitrarily large amount of negative energy in a given region of space at a fixed time. This class of states thus provides an explicit counterexample to the existence of a spatially averaged quantum inequality in four-dimensional spacetime.

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L. H. Ford, Adam D. Helfer, Thomas A. Roman. 2002-10-24. Spatially Averaged Quantum Inequalities Do Not Exist in Four-Dimensional Spacetime. https://doi.org/10.1103/physrevd.66.124012

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