Residual cut-off dependence and power counting: the deuteron as a case study

TL;DR

This paper investigates how the choice of regulator affects residual cutoff dependence in effective field theories, specifically examining the deuteron, and discusses implications for power counting methods.

Contribution

It demonstrates that regulator choice can influence the power law behavior of residual cutoff dependence, challenging assumptions in EFT power counting analysis.

Findings

Regulator dependence can alter residual cutoff behavior

Implications for EFT power counting validity

Highlights the importance of regulator choice in EFT analysis

Abstract

Effective field theories (EFTs) require regularization and renormalization to gain predictive power. While regularization is inconsequential from the point of view of the observable predictions of EFT -- in a renormalized theory we expect predictions to be regulator-independent once the cutoff is removed -- the particular details of regulator dependence might provide interesting insights into the inner workings of an EFT. In fact, the analysis of regulator dependence has been frequently suggested as a tool to study the ordering scheme or power counting of EFTs. We show here that the choice of the regulator might impact the power law properties of the residual cutoff dependence. If this conclusion were to be confirmed, it would have consequences on the validity of this method as a tool to analyze power counting.