Dynamical Casimir effect in nonlinear vibrating cavities

TL;DR

This paper investigates how nonlinearities in vibrating cavities influence the dynamical Casimir effect, revealing that two-loop quantum corrections grow quadratically over time, leading to a breakdown of semiclassical approximations.

Contribution

It extends previous work to include ideal vibrating cavities and semitransparent mirrors, demonstrating the significant impact of nonlinearities on particle production over time.

Findings

Two-loop corrections grow quadratically with time.

Nonlinearities cause breakdown of semiclassical approximation.

Bulk nonlinearities cannot be neglected for large times.

Abstract

Nonlinear terms in the equations of motion can induce secularly growing loop corrections to correlation functions. Recently such corrections were shown to affect the particle production by a nonuniformly moving ideal mirror. We extend this conclusion to the cases of ideal vibrating cavity and single semitransparent mirror. These models provide natural IR and UV scales and allow a more accurate study of the loop behavior. In both cases we confirm that two-loop correction to the Keldysh propagator quadratically grows with time. This growth indicates a breakdown of the semiclassical approximation and emphasizes that bulk nonlinearities in the dynamical Casimir effect cannot be neglected for large evolution times.