Description of a domain by a squeezed state in a scalar field theory

TL;DR

This paper models a domain in scalar quantum field theory using a squeezed state, calculating properties like momentum distribution and chaoticity, and applies the method to a pion field example.

Contribution

It introduces a novel approach to describe a domain with a squeezed state in scalar field theory, linking quantum state properties to observable distributions.

Findings

Momentum is inversely proportional to domain size

Chaoticity reflects the ratio of squeeze to coherent regions

Gaussian distributions effectively describe the domain state

Abstract

The author attempted to describe a domain by using a squeezed state in quantum field theory. An extended squeeze operator was used to construct the state. In a scalar field theory, the author described a domain that the distributions of the condensate and of the fluctuation are Gaussian. The momentum distribution, chaoticity and correlation length were calculated. It was found that the typical value of the momentum is about the inverse of the domain size, and that the chaoticity reflects the ratio of the size of the squeeze region to that of the coherent region. The results indicate that the quantum state of a domain is surmised by these quantities under the assumption that the distributions are Gaussian. As an example, this method was applied to a pion field, and the momentum distribution and the chaoticity were shown.