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arXiv · 1907.08221

If the Weak Were Strong and the Strong Were Weak

Nakarin Lohitsiri·David Tong
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Abstract

We explore the phase structure of the Standard Model as the relative strengths of the SU(2) weak force and SU(3) strong force are varied. With a single generation of fermions, the structure of chiral symmetry breaking suggests that there is no phase transition as we interpolate between the SU(3)-confining phase and the SU(2)-confining phase. Remarkably, the massless left-handed neutrino, familiar in our world, morphs smoothly into a massless right-handed down-quark. With multiple generations, a similar metamorphosis occurs, but now proceeding via a phase transition. In the second half of the paper we introduce a two-parameter extension of the Standard Model, a chiral gauge theory with gauge group U(1) x Sp(r) x SU(N). We again explore the phase structure of the theory as the relative strengths of the Sp(r) and SU(N) gauge couplings vary.

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Nakarin Lohitsiri, David Tong. 2019-07-18. If the Weak Were Strong and the Strong Were Weak. https://doi.org/10.21468/scipostphys.7.5.059

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