Comment on "First-order phase transitions: equivalence between bimodalities and the Yang-Lee theorem"

Abstract

I discuss the validity of a result put forward recently by Chomaz and Gulminelli [Physica A 330 (2003) 451] concerning the equivalence of two definitions of first-order phase transitions. I show that distributions of zeros of the partition function fulfilling the conditions of the Yang-Lee Theorem are not necessarily associated with nonconcave microcanonical entropy functions or, equivalently, with canonical distributions of the mean energy having a bimodal shape, as claimed by Chomaz and Gulminelli. In fact, such distributions of zeros can also be associated with concave entropy functions and unimodal canonical distributions having affine parts. A simple example is worked out in detail to illustrate this subtlety.

3 pages, revtex4, 1 figure

References in corpus (3)

• An Introduction to the Thermodynamic and Macrostate Levels of Nonequivalent Ensembles
• Thermodynamic versus statistical nonequivalence of ensembles for the mean-field Blume-Emery-Griffiths model
• First order phase transitions: equivalence between bimodalities and the Yang-Lee theorem

Cited by in corpus (4)

• The large deviation approach to statistical mechanics
• Generalized canonical ensembles and ensemble equivalence
• Negative magnetic susceptibility and nonequivalent ensembles for the mean-field ${\varphi }^4$ spin model
• Partial equivalence of statistical ensembles in a simple spin model with discontinuous phase transitions