Circulant $L$-ensembles in the thermodynamic limit

TL;DR

This paper studies circulant L-ensembles, a class of determinantal point processes with translational invariance, deriving formulas for their thermodynamic properties and connecting them to models in statistical mechanics and random matrix theory.

Contribution

It provides explicit formulas for pressure and correlation kernels of circulant L-ensembles in the thermodynamic limit, including special cases related to free fermions and random matrix models.

Findings

Pressure formulas derived for circulant L-ensembles.

Correlation kernel expressions in the thermodynamic limit.

Verification of the hole probability and pressure relationship.

Abstract

$L$-ensembles are a class of determinantal point processes which can be viewed as a statistical mechanical systems in the grand canonical ensemble. Circulant $L$-ensembles are the subclass which are locally translationally invariant and furthermore subject to periodic boundary conditions. Existing theory can very simply be specialised to this setting, allowing for the derivation of formulas for the system pressure, and the correlation kernel, in the thermodynamic limit. For a one-dimensional domain, this is possible when the circulant matrix is both real symmetric, or complex Hermitian. The special case of the former having a Gaussian functional form for the entries is shown to correspond to free fermions at finite temperature, and be generalisable to higher dimensions. A special case of the latter is shown to be the statistical mechanical model introduced by Gaudin to interpolate between Poisson and unitary symmetry statistics in random matrix theory. It is shown in all cases that the compressibility sum rule for the two-point correlation is obeyed, and the small and large distance asymptotics of the latter are considered. Also, a conjecture relating the asymptotic form of the hole probability to the pressure is verified.