Theory HEP Seminar

Non-equilibrium fermion production on the lattice

Daniil Gelfand

Heidelberg

A modern approach to far from equilibrium fermion production using real-time simulations will be presented. This method is applied to study quark production from bosonic instabilities in QCD and effective models as well as pair production in abelian gauge theories. We discuss the role of quantum effects in presence of non-perturbatively high bosonic fluctuations and compare to approximative descriptions based on homogeneous background fields. Both strongly and weakly coupled scenarios are considered and the emergence of power-law and Fermi-Dirac distributions of quark occupation numbers is observed. The latter result is being used to define a non-equilibrium quasi-temperature for quarks. In 1+1 dimensional QED we are able to investigate the build-up of a linear rising potential between produced fermion bunches and the striking phenomenon of dynamical string breaking, which strongly resembles the corresponding effect in QCD.