# Strong dynamics with matter in multiple representations: SU(4) gauge theory with fundamental and sextet fermions

## TL;DR

This paper conducts a non-perturbative lattice investigation of an SU(4) gauge theory with multiple fermion representations, exploring its phase structure and spectrum relevant to models beyond the Standard Model.

## Contribution

It provides the first detailed lattice study of SU(4) with fundamental and sextet fermions, relevant for partial-compositeness models, including phase structure and spectral results.

## Key findings

- Identified the phase structure of the SU(4) theory with multiple fermion representations.
- Computed the spectrum of states and Dirac operator eigenvalues.
- Discussed the potential for lighter top-quark partners in extended models.

## Abstract

We present a non-perturbative lattice study of SU(4) gauge theory with two flavors of fermions in the fundamental representation and two in the two-index antisymmetric representation: a theory closely related to a minimal partial-compositeness model for physics beyond the Standard Model, that was proposed by G. Ferretti. We discuss the phase structure of the lattice theory and report results for various observables of interest, including the masses of states obtained from different combinations of valence fermions and the spectrum of the Dirac operator. Finally, we comment on the extension of this type of studies to other partial-compositeness models (including, in particular, one that was recently suggested by H. Gertov et al.), which could admit lighter top-quark partners, highlighting some key features of our lattice simulation algorithm, that make it suitable for such generalizations.