Sören Schlichting

Over-populated gauge fields on the lattice

We study nonequilibrium dynamics of SU(2) pure gauge theory starting from initial over-population, where intense classical gauge fields are characterized by a single momentum scale Q_s. Classical-statistical lattice simulations indicate a quick evolution towards an approximate scaling behavior with exponent 3/2 at intermediate times. Remarkably, the value for the scaling exponent may be understood as arising from the leading O(g^2) contribution in the presence of a time-dependent background field. The phenomenon is associated to weak wave turbulence describing an energy cascade towards higher momenta. This particular aspect is very similar to what is observed for scalar theories, where an effective cubic interaction arises because of the presence of a time-dependent Bose condensate.

The nonlinear glasma

We study the evolution of quantum fluctuations in the Glasma created immediately after the collision of heavy nuclei. It is shown how the presence of instabilities leads to an enhancement of non-linear interactions among initially small fluctuations. The non-linear dynamics leads to an enhanced growth of fluctuations in a large momentum region exceeding by far the originally unstable band. We investigate the dependence on the coupling constant at weak coupling using classical statistical lattice simulations for SU(2) gauge theory and show how these non-linearities can be analytically understood within the framework of two-particle irreducible (2PI) effective action techniques. The dependence on the coupling constant is only logarithmic in accordance with analytic expectations. Concerning the isotropization of bulk quantities, our results indicate that the system exhibits an order-one anisotropy on parametrically large time scales. Despite this fact, we find that gauge invariant pressure correlation functions seem to exhibit a power law behavior characteristic for wave turbulence.

Nonequilibrium study of the chiral magnetic effect from real-time simulations with dynamical fermions

We present a real-time lattice approach to study the non-equilibrium dynamics of vector and axial charges in

Nonlinear amplification of instabilities with longitudinal expansion

SU(N) times U(1)

Out of equilibrium dynamics of coherent non-abelian gauge fields

gauge theories. Based on a classical description of the non-Abelian and Abelian gauge fields, we include dynamical fermions and develop operator definitions for (improved) Wilson and overlap fermions that allow us to study real-time manifestations of the axial anomaly from first principles. We present a first application of this approach to anomalous transport phenomena such as the Chiral Magnetic Effect (CME) and Chiral Separation Effect (CSE) by studying the dynamics of fermions during and after a

Predictions for cold nuclear matter effects in p+Pb collisions at sNN=8.16 TeV

SU(N)

Importance of initial and final state effects for azimuthal correlations in p+Pb collisions

sphaleron transition in the presence of a

Initial conditions for hydrodynamics from kinetic theory equilibration

U(1)

Linearly polarized gluons and axial charge fluctuations in the glasma

magnetic field. We investigate the fermion mass and magnetic field dependence of the suggested signatures of the CME and CSE and point out some important aspects which need to be accounted for in the macroscopic description of anomalous transport phenomena.

Collectivity in small systems - Initial state vs. final state effects

We study the dynamics of nonequilibrium instabilities in anisotropically expanding systems. The most prominent example of such a system is the Glasma in the context of relativistic heavy-ion collision experiments, where the expansion is a consequence of approximately boost-invariant initial conditions. Here we consider the problem of parametric resonance in scalar