Particle Detectors, Cavities, and the Weak Equivalence Principle

TL;DR

This paper investigates a quantum version of the weak equivalence principle by comparing detector responses in different accelerated cavity scenarios, revealing that field non-locality allows distinction between the setups regardless of field mass or state.

Contribution

It introduces a quantum test of the weak equivalence principle using particle detectors and cavity acceleration, highlighting the role of field non-locality.

Findings

Detectors can distinguish between accelerated cavity and crossing detector scenarios.

Field non-locality enables differentiation regardless of vacuum or excited states.

Mass of the scalar field influences the detector responses.

Abstract

We analyze a quantum version of the weak equivalence principle, in which we compare the response of a static particle detector crossed by an accelerated cavity with the response of an accelerated detector crossing a static cavity in (1+1)-dimensional flat spacetime. We show, for both massive and massless scalar fields, that the non-locality of the field is enough for the detector to distinguish the two scenarios. We find this result holds for vacuum and excited field states of different kinds and we clarify the role of field mass in this setup.