Equilibrium equation of state of a hard sphere binary mixture at very large densities using replica exchange Monte-Carlo simulations

TL;DR

This paper employs replica exchange Monte-Carlo simulations to accurately determine the equilibrium equation of state for a binary hard sphere mixture at very high densities, challenging previous assumptions about thermodynamic glass transitions.

Contribution

It introduces a simulation approach capable of reaching high densities and provides evidence against pressure discontinuities indicating thermodynamic glass transitions.

Findings

No pressure discontinuity near dynamic glass singularities

Simulations up to N=100 particles at high densities

Proposes scenarios for fluid state behavior in the thermodynamic limit

Abstract

We use replica exchange Monte-Carlo simulations to measure the equilibrium equation of state of the disordered fluid state for a binary hard sphere mixture up to very large densities where standard Monte-Carlo simulations do not easily reach thermal equilibrium. For the moderate system sizes we use (up to N=100), we find no sign of a pressure discontinuity near the location of dynamic glass singularities extrapolated using either algebraic or simple exponential divergences, suggesting they do not correspond to genuine thermodynamic glass transitions. Several scenarios are proposed for the fate of the fluid state in the thermodynamic limit.