Dissipation and energy gap

TL;DR

This paper explores how anharmonicity in field theories causes dissipation and leads to the emergence of gapped energy and momentum states, revealing new dispersion relations and properties.

Contribution

It demonstrates that anharmonicity can induce a gapped energy state with an explicit energy gap, extending understanding of dissipative effects in field theories.

Findings

Anharmonicity causes dissipation of plane waves.

Gapped energy states emerge with explicit energy gaps.

Connections between gapped energy and momentum states are discussed.

Abstract

The effect of anharmonicity (coupling) in the field theory generally result in dissipation of plane waves. It has been appreciated that anharmonicity and ensuing dissipation of plane waves can be accompanied by the emergence of the gapped momentum state. Here, we show that the same effect can lead to a gapped energy state and a dispersion relation where the frequency (energy) gap emerges explicitly. We discuss several notable properties of gapped energy and momentum states and connections between them.