Varieties of electrically charged physical states in SU(2)$\times$U(1) lattice gauge Higgs theory

TL;DR

This paper explores new types of electrically charged and neutral states in SU(2)×U(1) lattice gauge Higgs theory, revealing multiple charged particle states with different masses.

Contribution

It introduces novel constructions of charged and neutral states based on how static sources are dressed by dynamical fields in lattice gauge theory.

Findings

Neutral static fermion is lighter than charged fermions.

Charged fermion spectrum contains at least two states with different masses.

Abstract

We consider a quenched SU(2)$\times$U(1) gauge Higgs theory on the lattice, coupled to a static vector-like fermion which, in this case, is in the same gauge group representation as the Higgs field. Physical (i.e. locally gauge invariant) electrically charged and electrically neutral states of matter particles in the electroweak theory were described decades ago, but those constructions do not exhaust all the possibilities, and new types of electrically charged/neutral states, orthogonal to former constructions, are described here. The difference has to do with how the static source, which by itself does not create a physical state, is dressed by dynamical fields. We find that, unsurprisingly, the neutral static fermion is much lighter than any of the charged fermion states. But a lattice study of the propagation of the charged fermion states indicates the existence of (at least) two particle states with different masses in charged particle spectrum.