Trace anomaly and infrared cutoffs

TL;DR

This paper explores how the effective average action, which incorporates an infrared cutoff, modifies the scale Ward identity and links the trace anomaly to the Wilsonian renormalization group, enhancing understanding of quantum field theory.

Contribution

It derives the modified scale Ward identity for the effective average action and clarifies its relation to the trace anomaly within the Wilsonian framework.

Findings

Modified scale Ward identity incorporating infrared cutoff

Explicit relation between trace anomaly and Wilsonian renormalization group

Insights into the role of the cutoff in quantum field theory

Abstract

The Effective Average Action is a form of effective action which depends on a cutoff scale suppressing the contribution of low momentum modes in the functional integral. It reduces to the ordinary effective action when the cutoff scale goes to zero. We derive the modifications of the scale Ward identity due to this cutoff and show how the resulting identity then intimately relates the trace anomaly to the Wilsonian realisation of the renormalization group.