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DOE OSTI · 3007762

Investigating solutions to the strong CP problem (Final Technical Report)

Harigaya, Keisuke [Univ. of Chicago, IL (United States)] (ORCID:0000000263238839)
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Abstract

The weak interaction violates a symmetry between particles and anti-particles that is called a CP symmetry. This violation is expected to induce CP violation in the strong interaction by a large amount. However, observations show that the CP violation in the strong interaction is smaller than expected by more than ten orders of magnitude. This discrepancy is called the strong CP problem, and solving it has been one of the motivations for constructing a theory beyond the Standard Model (SM). In this research program, the PI investigated possible signals of solutions to the strong CP problem. The signals were predicted for a variety of experiments and observations. These predictions bridge different subfields of particle physics, cosmology, and astrophysics that are otherwise disconnected. As a byproduct, the PI also applied the techniques developed in this study to theories with axion-like particles to reveal signals of axion-like particles.

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Harigaya, Keisuke [Univ. of Chicago, IL (United States)] (ORCID:0000000263238839). 2025-12-12. Investigating solutions to the strong CP problem (Final Technical Report). https://doi.org/10.2172/3007762

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