Solving the strong CP problem

2025/01/27 by Alessandro Strumia, Strumia, Alessandro
Engineering · #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #Optimization and Packing Problems

paper · pdf · doi:10.48550/arxiv.2501.16427

openalex publication_date 2025/01/27 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

I briefly review solutions to the strong CP problem based on axions, parity invariance, CP-invariance, and present a new idea based on CP as part of a spontaneously broken flavour symmetry such as a U(1) or modular invariance.

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