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arXiv · 2501.19212

The observable spectrum for GUT-like theories

Elizabeth Dobson·Axel Maas·Simon Plätzer·Bernd Riederer
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Abstract

The spectrum of nonabelian gauge theories cannot be described in terms of elementary particles, and so must be constructed from gauge-invariant composite operators, even in the presence of a Brout--Englert--Higgs effect. This leads to qualitative discrepancies in the prediction of the spectrum between perturbation theory and a full non-perturbative treatment in many theories. This is especially noticeable for GUTs. We present results corroborating this general statement using lattice simulations for a ''GUT-like'' toy theory, $\mathrm{SU}(3)$ Yang--Mills theory coupled to a Higgs field in the fundamental representation. Despite the apparent simplicity of the model, we find a rich spectrum with some previously unseen features. We also outline the next steps required to generate a large operator basis to extend this investigation to more realistic GUTs.

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Elizabeth Dobson, Axel Maas, Simon Plätzer, Bernd Riederer. 2025-01-31. The observable spectrum for GUT-like theories. https://arxiv.org/abs/2501.19212

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