Plasmon mass scale and quantum fluctuations of classical fields on a real time lattice

¹ Theoretical Physics Department, CERN, Geneva, Switzerland
² Faculty of Science and Technology, University of Stavanger, 4036 Stavanger, Norway
³ Department of Physics, P.O. Box 35, 40014 University of Jyväskylä, Finland
⁴ Helsinki Institute of Physics, P.O. Box 64, 00014 University of Helsinki, Finland

^* Speaker, e-mail: jarkko.t.peuron@student.jyu.fi

Published online: 26 March 2018

Abstract

Classical real-time lattice simulations play an important role in understanding non-equilibrium phenomena in gauge theories and are used in particular to model the prethermal evolution of heavy-ion collisions. Above the Debye scale the classical Yang-Mills (CYM) theory can be matched smoothly to kinetic theory. First we study the limits of the quasiparticle picture of the CYM fields by determining the plasmon mass of the system using 3 different methods. Then we argue that one needs a numerical calculation of a system of classical gauge fields and small linearized fluctuations, which correspond to quantum fluctuations, in a way that keeps the separation between the two manifest. We demonstrate and test an implementation of an algorithm with the linearized fluctuation showing that the linearization indeed works and that the Gauss’s law is conserved.