852 research outputs found
Spectral sum rules and Selberg's integral
Using Selberg's integral formula we derive all Leutwyler-Smilga type sum
rules for one and two flavors, and for each of the three chiral random matrix
ensembles. In agreement with arguments from effective field theory, all sum
rules for coincide for the three ensembles. The connection between
spectral correlations and the low-energy effective partition function is
discussed.Comment: 10 pages, SUNY-NTG-94/
Microscopic spectra of dirac operators and finite-volume partition functions
Exact results from random matrix theory are used to systematically analyse the relationship
between microscopic Dirac spectra and finite-volume partition functions. Results are presented
for the unitary ensemble, and the chiral analogs of the three classical matrix ensembles: unitary,
orthogonal and symplectic, all of which describe universality classes of SU(Nc) gauge theories with
Nf fermions in different representations. Random matrix theory universality is reconsidered in this
new light
Universal Spectral Correlators and Massive Dirac Operators
We derive the large-N spectral correlators of complex matrix ensembles with
weights that in the context of Dirac spectra correspond to N_f massive
fermions, and prove that the results are universal in the appropriate scaling
limits. The resulting microscopic spectral densities satisfy exact spectral sum
rules of massive Dirac operators in QCD.Comment: 15 pages, LaTeX. Typographical errors corrected. Note adde
Universal spectral correlations of the Dirac operator at finite temperature
Using the graded eigenvalue method and a recently computed extension of the
Itzykson-Zuber integral to complex matrices, we compute the -point spectral
correlation functions of the Dirac operator in a chiral random matrix model
with a deterministic diagonal matrix added. We obtain results both on the scale
of the mean level spacing and on the microscopic scale. We find that the
microscopic spectral correlations have the same functional form as at zero
temperature, provided that the microscopic variables are rescaled by the
temperature-dependent chiral condensate.Comment: 27 pages, no figures, uses elsart.st
Finite volume partition functions and Itzykson-Zuber integrals
We find the finite volume QCD partition function for arbitrary quark masses.
This is a generalization of a result obtained by Leutwyler and Smilga for equal
quark masses. Our result is derived in the sector of zero topological charge
using a generalization of the Itzykson-Zuber integral appropriate for arbitrary
complex matrices. We present a conjecture regarding the result for arbitrary
topological charge which reproduces the Leutwyler-Smilga result in the limit of
equal quark masses. We derive a formula of the Itzykson-Zuber type for
arbitrary {\em rectangular} complex matrices, extending the result of Guhr and
Wettig obtained for {\em square} matrices.Comment: 11 pages, LATEX. A minor typo in equation (12) has been corrected in
the revised versio
Logarithmic Universality in Random Matrix Theory
Universality in unitary invariant random matrix ensembles with complex matrix
elements is considered. We treat two general ensembles which have a determinant
factor in the weight. These ensembles are relevant, e.g., for spectra of the
Dirac operator in QCD. In addition to the well established universality with
respect to the choice of potential, we prove that microscopic spectral
correlators are unaffected when the matrix in the determinant is replaced by an
expansion in powers of the matrix. We refer to this invariance as logarithmic
universality. The result is used in proving that a simple random matrix model
with Ginsparg-Wilson symmetry has the same microscopic spectral correlators as
chiral random matrix theory.Comment: 16 pages, latex2
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