Inexistence of equilibrium states at absolute negative temperatures

Abstract

We show that states of macroscopic systems with purported absolute negative temperatures are not stable under small, yet arbitrary, perturbations. We prove the previous statement using the fact that, in equilibrium, the entropy takes its maximum value. We discuss that, while Ramsey theoretical reformulation of the Second Law for systems with negative temperatures is logically correct, it must be a priori assumed that those states are in thermodynamic equilibrium. Since we argue that those states cannot occur, reversible processes are impossible and, thus, Ramsey identification of negative absolute temperatures is untenable.

20 pages, 5 figures

References in corpus (3)

• Negative Absolute Temperature for Motional Degrees of Freedom
• Equilibration rates and negative absolute temperatures for ultracold atoms in optical lattices
• Atomic Gases at Negative Kinetic Temperature

Cited by in corpus (21)

• Gibbs, Boltzmann, and negative temperatures
• Statistical Mechanics of Systems with Negative Temperature
• On the dispute between Boltzmann and Gibbs entropy
• Negative temperatures and the definition of entropy
• Quantum systems correlated with a finite bath: nonequilibrium dynamics and thermodynamics
• Phase transitions at high energy vindicate negative microcanonical temperature
• Statistical mechanics of systems with long-range interactions and negative absolute temperature
• Topological Approach to Microcanonical Thermodynamics and Phase Transition of Interacting Classical Spins
• The thermodynamic entropy of a macroscopic quantum system is a continuous function of energy
• Cosmology with Negative Absolute Temperatures
• Microcanonical entropy for classical systems
• Origin of Negative Temperatures in Systems Interacting with External Fields
• Critique of the Gibbs volume entropy and its implication
• Feasible platform to study negative temperatures
• Negative-temperature Fourier transport in one-dimensional systems
• H-theorem at negative temperature: the random exchange model with bounds
• Resolving the debate about proposed expressions for the classical entropy
• How Geometrical Frustrated Systems Challenge our Notion of Thermodynamics
• Thermodynamic laws in isolated systems
• Geometrically Frustrated Systems which are as Singles Hotter Than in Company
• Effective Equations in complex systems: from Langevin to machine learning