HEP/Astro Seminar -- Wednesday, 28 February 2001

Chiral perturbation theory for lattice QCD

Steve Sharpe, (University of Washington)

Abstract

Chiral extrapolations are an essential adjunct to present and forseeable lattice simulations, because physical up and down quarks are too light to be included as dynamical quarks. I discuss the issues facing such extrapolations, and describe how one can make use of partially quenched simulations (those with differing valence and dynamical quark masses) in order to improve the extrapolations. This leads to the surprising conclusion that one can use simulations of unphysical theories (non-unitary, non-causal) to determine physical parameters, without introducing uncontrolled errors.

Reference

S. Sharpe and N. Shoresh, ``Physical results from unphysical simulations,'' Phys. Rev. D62 (2000) 094503 , [ hep-lat/0006017 ].

15:30, Smith Lab 4079