Testing the Coherent State Description of Radiation Fields

TL;DR

This paper introduces practical criteria using counting statistics to test whether radiation fields are truly quantum or can be described classically as coherent states, with implications for gravitational radiation.

Contribution

It presents simple quantitative tests based on counting statistics to evaluate the quantum nature of radiation fields, especially in gravitational contexts.

Findings

Criteria effectively distinguish quantum from classical fields.

Applicable to gravitational radiation with non-linear or stochastic sources.

Provides a practical method for testing the coherent state hypothesis.

Abstract

We propose simple quantitative criteria, based on counting statistics in resonant harmonic detectors, that probe the quantum mechanical character of radiation fields. They provide, in particular, practical means to test the null hypothesis that a given field is ``maximally classical'', i.e., accurately described by a coherent state. We suggest circumstances in which that hypothesis plausibly fails, notably including gravitational radiation involving non-linear or stochastic sourcing.