Exact flow equation for composite operators

TL;DR

This paper introduces an exact flow equation for composite operators, enabling scale-dependent analysis of fermionic interactions and effective degrees of freedom, facilitating partial bosonization and dynamic change of variables.

Contribution

It presents a novel exact flow equation for composite operators, allowing for systematic scale-dependent transformations in quantum field theories.

Findings

Enables scale-dependent partial bosonization.

Tracks relations between composite fields and operators.

Facilitates effective change of degrees of freedom.

Abstract

We propose an exact flow equation for composite operators and their correlation functions. This can be used for a scale-dependent partial bosonization or "flowing bosonization" of fermionic interactions, or for an effective change of degrees of freedom in dependence on the momentum scale. The flow keeps track of the scale dependent relation between effective composite fields and corresponding composite operators in terms of the fundamental fields.