Eur. Phys. J. A (2017) 53: 232
https://doi.org/10.1140/epja/i2017-12432-1

Regular Article - Theoretical Physics

Hot origin of the Little Bang

¹ Bogolyubov Institute for Theoretical Physics, Metrolohichna 14b, 03680, Kiev, Ukraine
² Institut für Theoretische Physik, Universität Heidelberg, Philosophenweg 16, 69120, Heidelberg, Germany
³ ExtreMe Matter Institute EMMI, GSI Helmholtzzentrum für Schwerionenforschung, Planckstraße 1, 64291, Darmstadt, Germany

^* e-mail: akkelin@bitp.kiev.ua

Received: 14 July 2017
Accepted: 16 November 2017
Published online: 4 December 2017

Abstract

Ultrarelativistic heavy ion collisions produce a quark-gluon matter which lies in the future light cone originating from given points on the t = z = 0 plane of the Minkowski spacetime manifold. We show that in a weak coupling regime the Minkowski vacuum of massless fields presents itself in the “Little Bang” region as a thermal state of low particles, in close analogy to the Unruh effect for uniformly accelerated observers which are causally restricted to a Rindler wedge. It can shed some light on the mechanisms of early time thermalization in ultrarelativistic heavy ion collisions.