Lattice QCD simulations at non-zero baryochemical potential

by Attila Pasztor (Eötvös Loránd University (ELTE))

Tuesday 2 May 2023, 16:00 → 18:00 Europe/Zurich

Zoom (CERN)

In order to circumvent the infamous sign problem, lattice QCD studies of hot and dense strongly interacting matter mostly rely on extrapolations from zero or purely imaginary chemical potentials. The ill-posedness of numerical analytic continuation, however, puts severe limitations on the reliability of such calculations. To obtain more direct results, certain reweighting techniques, such as sign or phase reweighting, can be used. These allow one to obtain results at a finite baryon density without the uncontrolled systematic uncertainties associated with analytic continuation methods. The main bottleneck of these methods is the sign problem itself. However, the sign problem can be kept under numerical control at least for the range of the RHIC Beam Energy Scan in the chemical potential. Thus, reweighting studies already produced some phenomenologically interesting results in this regime. I will briefly review recent progress with this approach and discuss future prospects.