Detection of negative energy: 4-dimensional examples

TL;DR

This paper investigates how switched particle detectors respond to static negative energy densities and fluxes, deriving quantum inequalities and exploring implications for the quantum equivalence principle and thermodynamics.

Contribution

It introduces a model analyzing detector responses to negative energy, deriving quantum inequalities, and examining foundational questions like the quantum equivalence principle.

Findings

Switching induces detector excitation even in vacuum.

Negative energy can suppress detector excitation.

Quantum inequalities constrain negative energy effects.

Abstract

We study the response of switched particle detectors to static negative energy densities and negative energy fluxes. It is demonstrated how the switching leads to excitation even in the vacuum and how negative energy can lead to a suppression of this excitation. We obtain quantum inequalities on the detection similar to those obtained for the energy density by Ford and co-workers and in an `operational' context by Helfer. We revisit the question `Is there a quantum equivalence principle?' in terms of our model. Finally, we briefly address the issue of negative energy and the second law of thermodynamics.