Is the physical vacuum a preferred frame ?

TL;DR

This paper explores whether the physical vacuum acts as a preferred frame by proposing an experimental test to distinguish between Lorentz-invariant and preferred frame models of the vacuum.

Contribution

It introduces an experimental approach to determine if the vacuum's ground state defines a preferred frame or preserves Lorentz invariance.

Findings

Proposes an experimental test for vacuum frame preference

Highlights the theoretical motivation for both scenarios

Aims to empirically resolve the vacuum frame debate

Abstract

It is generally assumed that the physical vacuum of particle physics should be characterized by an energy momentum tensor in such a way to preserve exact Lorentz invariance. On the other hand, if the ground state were characterized by its energy-momentum vector, with zero spatial momentum and a non-zero energy, the vacuum would represent a preferred frame. Since both theoretical approaches have their own good motivations, we propose an experimental test to decide between the two scenarios.