CERN Lattice Coffee

Towards thermal dynamics on the lattice with exponentially improved accuracy

by Alexander Rothkopf (Heidelberg University)

Europe/Zurich
4/2-037 - TH meeting room (CERN)

4/2-037 - TH meeting room

CERN

18
Show room on map
Description
The non-perturbative computation of dynamical quantities, such as QCD transport coefficients or the potential between heavy quarks is an active subject of current research. It is of central interest in the study of relativistic heavy-ion collisions as it promises to connect successful phenomenological frameworks, such as relativistic hydrodynamics, with our understanding of the microscopic laws governing the strong interactions. One possible route is to compute such dynamical observables via first principles lattice QCD, which however is hampered by the simulations being carried out in an artificial Euclidean time. To analytically continue the simulated data to the relevant Minkoswki domain, an ill-posed and exponentially hard inverse problem needs to be solved. Here we report on a recent proposal [1] of simulating thermal quantum fields in imaginary frequencies instead of imaginary time. On the one hand in our approach the inverse problem itself is much better conditioned. On the other hand we introduce an independent discretization in imaginary frequencies that allows us to resolve correlation functions in between the usual Matsubara frequencies. First results from a (0+1)d toy model are presented.