Strongly Interacting Dynamics beyond the Standard Model on a Spacetime Lattice

TL;DR

This paper reviews lattice simulations of strongly interacting theories beyond the Standard Model, focusing on the Minimal Walking Technicolour scenario, and reports initial numerical results on its infrared properties and phenomenological parameters.

Contribution

It provides the first numerical determinations of the chiral condensate anomalous dimension in the Minimal Walking Technicolour model using lattice simulations.

Findings

The theory exhibits an infrared fixed point influencing large-distance physics.

Finite size scaling yields an anomalous dimension $oldsymbol{0.05 extless \gamma extless 0.25}$.

Lattice techniques are promising for studying strongly interacting BSM theories.

Abstract

Strong theoretical arguments suggest that the Higgs sector of the Standard Model of the Electroweak interactions is an effective low-energy theory, with a more fundamental theory that is expected to emerge at an energy scale of the order of the TeV. One possibility is that the more fundamental theory be strongly interacting and the Higgs sector be given by the low-energy dynamics of the underlying theory. We review recent works aimed to determining observable quantities by numerical simulations of strongly interacting theories proposed in the literature for explaining the Electroweak symmetry breaking mechanism. These investigations are based on Monte Carlo simulations of the theory formulated on a spacetime lattice. We focus on the so-called Minimal Walking Technicolour scenario, a SU(2) gauge theory with two flavours of fermions in the adjoint representation. The emerging picture is that this theory has an infrared fixed point that dominates the large distance physics. We shall discuss the first numerical determinations of quantities of phenomenological interest for this theory and analyse future directions of quantitative studies of strongly interacting beyond the Standard Model theories with Lattice techniques. In particular, we report on a finite size scaling determination of the chiral condensate anomalous dimension $\gamma$, for which we find $0.05 \le \gamma \le 0.25$.