Supersymmetric Quenching of the Toda Lattice Equation

TL;DR

This paper demonstrates that the spectral determinants of the Dirac operator in QCD satisfy a Toda lattice equation, with a supersymmetric method providing a rigorous derivation of the quenched limit and spectral correlation functions.

Contribution

It introduces a supersymmetric approach to derive the Toda lattice equation for spectral determinants, avoiding analytic continuation and clarifying the factorization of spectral correlations.

Findings

The spectral determinants satisfy a Toda lattice equation.

The supersymmetric method yields the quenched limit without analytic continuation.

Factorization of spectral correlation functions follows naturally from both approaches.

Abstract

The average of the ratio of powers of the spectral determinants of the Dirac operator in the $\epsilon$-regime of QCD is shown to satisfy a Toda lattice equation. The quenched limit of this Toda lattice equation is obtained using the supersymmetric method. This super symmetric approach is then shown to be equivalent to taking the replica limit of the Toda lattice equation. Among other, the factorization of the microscopic spectral correlation functions of the QCD Dirac operator into fermionic and bosonic partition functions follows naturally from both approaches. While the replica approach relies on an analytic continuation in the number of flavors no such assumptions are made in the present approach where the numbers of flavors in the Toda lattice equation are strictly integer.