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arXiv · 2506.01911

Parity solves the Strong CP problem

Ravi Kuchimanchi
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Abstract

A recent paper "What can solve the strong CP problem?" goes counter to conventional wisdom by arguing that the universe was in an initial state that combines different eigenstates of $\theta$ (of the theta vacuum of QCD), and asserts that for such an initial state, axionless solutions to the Strong CP Problem based on P and CP symmetries will not work. We discuss the nature of the theta vacuum in light of this work, and find that the conventional framing and solutions based on P and CP symmetries are on a firm footing.

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Ravi Kuchimanchi. 2025-06-02. Parity solves the Strong CP problem. https://arxiv.org/abs/2506.01911

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