Decay of Scalar Condensation in Quantum Field Theory

TL;DR

This paper develops a quantum field theory approach to calculate decay rates of scalar-field condensates, treating them as coherent states, and applies the method to specific decay channels including pair production and anomaly-induced decay.

Contribution

It introduces a systematic formalism for computing decay rates of scalar condensates as coherent states using unitarity, extending previous methods to include anomaly effects.

Findings

Derived explicit decay rate formulas for scalar condensates

Validated the formalism against parametric-resonance results

Extended decay analysis to anomaly-induced processes

Abstract

We consider decay processes of scalar-field condensation in the framework of well-established quantum field theory. We postulate that the quantum state corresponding to the scalar-field condensation is so-called coherent state with discussing the validity of such a treatment. We show that, by using the unitarity relation of the scattering matrix, decay rate of the coherent state is systematically calculated. We apply our procedure to derive explicit formulae of decay rates for two cases: (i) we study the case where the scalar condensation decays into a pair of scalar particles and show that our formalism reproduces the results obtained from the parametric-resonance analysis, and (ii) we also calculate the decay rate when the coherent state decays via anomaly.