5,614 research outputs found
Chiral Symmetry Breaking and the Dirac Spectrum at Nonzero Chemical Potential
The relation between the spectral density of the QCD Dirac operator at
nonzero baryon chemical potential and the chiral condensate is investigated. We
use the analytical result for the eigenvalue density in the microscopic regime
which shows oscillations with a period that scales as 1/V and an amplitude that
diverges exponentially with the volume . We find that the discontinuity
of the chiral condensate is due to the whole oscillating region rather than to
an accumulation of eigenvalues at the origin. These results also extend beyond
the microscopic regime to chemical potentials .Comment: 4 pages, 1 figur
Overlap Dirac operator at nonzero chemical potential and random matrix theory
We show how to introduce a quark chemical potential in the overlap Dirac
operator. The resulting operator satisfies a Ginsparg-Wilson relation and has
exact zero modes. It is no longer gamma_5-hermitian, but its nonreal
eigenvalues still occur in pairs. We compute the spectral density of the
operator on the lattice and show that, for small eigenvalues, the data agree
with analytical predictions of nonhermitian chiral random matrix theory for
both trivial and nontrivial topology.Comment: 4 pages, 2 figure
- …