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arXiv · 2306.12227

Testing $\chi$PT with the masses of the Nambu-Goldstone bosons

H. Leutwyler
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Abstract

The spontaneous breakdown of an approximate symmetry implies that the spectrum of the theory contains approximately massless particles. The hidden symmetry very strongly constrains their masses. A numerical evaluation of these constraints on the lattice would allow a more precise determination of the quark mass ratios m_u:m_d:m_s and thereby reduce some of the uncertainties encountered in precision flavour physics.

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H. Leutwyler. 2023-06-21. Testing $\chi$PT with the masses of the Nambu-Goldstone bosons. https://arxiv.org/abs/2306.12227

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