Is Anomaly Transferred thorough Multi-loop Process?

TL;DR

This paper examines whether anomaly transfer through multi-loop processes can produce an axion-like particle capable of solving the strong CP problem, concluding that it cannot due to mass acquisition and lack of necessary couplings.

Contribution

It provides a detailed analysis showing that multi-loop anomaly transfer does not generate a massless axion capable of addressing the strong CP problem.

Findings

Pseudo-Nambu-Goldstone boson acquires mass perturbatively

Massless mode lacks coupling to $G ilde{G}$

Multi-loop transfer does not solve the strong CP problem

Abstract

We investigated the multi-loop anomaly transfer to QCD sector from another one and its ability to solve strong CP problem. If the anomalous symmetry is spontaneously broken, its Nambu-Goldstone (NG) boson can couple to the QCD $G\tilde{G}$ through this transfer effect and behave as an axion. In our result, such a particle acquire mass pertabatively in fact, and really massless mode doesn't have couplings with $G\tilde{G}$. Consequently, this pseudo-NG boson is found not to solve the problem.