Unstable-Particle Gases: Negative-Lifetime Case

Abstract

The total excluded volume for a gas of stable particles with repulsive interactions is calculated. From this, it is possible to define an effective negative-interaction number density which is formally identical to the previously derived expression for the equilibrium number density of unstable particles. Pointing out that this allows the unstable-particle formalism to be extended to the negative-lifetime case, it is argued that unstable particles with negative lifetimes behave effectively like a gas of unstable holes.