Breakdown of staggered fermions at nonzero chemical potential
Loading...
Date
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Description
The staggered fermion determinant is complex when the quark chemical potential mu is nonzero. Its fourth root, used in simulations with dynamical fermions, will have phase ambiguities that become acute when Re mu is sufficiently large. We show how to resolve these ambiguities, but our prescription only works very close to the continuum limit. We argue that this regime is far from current capabilities. Other procedures require being even closer to the continuum limit, or fail altogether, because of unphysical discontinuities in the measure. At zero temperature the breakdown is expected when Re mu is greater than approximately half the pion mass. Estimates of the location of the breakdown at nonzero temperature are less certain.
6 pages RevTeX, 2 figures. Returning to v5 after erroneous replacement. Apologies
6 pages RevTeX, 2 figures. Returning to v5 after erroneous replacement. Apologies