A New Action for Heavy Lattice Fermions

TL;DR

This paper introduces a unified formalism for lattice fermions that encompasses Wilson, nonrelativistic, and static actions, valid across all quark mass regimes, simplifying the study of heavy and light quarks in lattice QCD.

Contribution

It presents a novel unified framework that seamlessly integrates different lattice fermion actions for all quark mass values, including heavy quarks.

Findings

Formalism reduces to Wilson light quark action when mq a << 1

Formalism reduces to nonrelativistic and static actions when mq a >> 1

Provides a consistent approach across all quark mass regimes

Abstract

I describe a unified formalism for lattice fermions, in which the relativistic action of Wilson and the nonrelativistic and static actions appear as special cases. It is valid at all values of $m_q a$, including $m_q a \approx 1$. In the limit $m_q a \ll 1 $, the formulation reduces to the light quark action of Wilson. In the limit $m_q a \gg 1 $, the formulation reduces to the nonrelativistic action of Thacker and Lepage, and to the static action of Eichten.