QCD is the fundamental quantum field theory that describes the strong interactions between particles. It is one of the basic building blocks of the Standard Model of Particle Physics and it is responsible for the formation of nuclear matter. In particular, QCD at high temperature plays a crucial role in understanding a large number of physical processes spanning from the cosmological evolution of the early universe to the interpretation of the experimental results of heavy ions collisions.
Due to asymptotic freedom, one could hope that a perturbative description of the dynamics of the theory becomes possible in the high temperature regime. However, the behaviour of the theory is strongly non-perturbative even at very high temperatures and the lattice is the only theoretical framework in which a first-principles, non-perturbative study is possible.
So far, most of the numerical studies on the lattice are restricted to the low temperature regime (T<2 GeV) due to technical limitations. In the present project we overcome those limitations by using a recent strategy - proposed and developed by our group - based on using shifted boundary conditions along the temporal direction.
Despite the novelty, that method has already given interesting results in the calculation of the Equation of State of SU(3) Yang-Mills theory and, more recently, in QCD for the calculation of the mesonic non-singlet screening masses projected onto zero Matsubara frequency.
The purpose of the present application is to extend the above calculations studying, for the first time, the non-static sector of the mesonic screening masses and the baryonic one over a wide range of temperatures. These quantities are very interesting observables from the phenomenological point of view, since they encode fundamental properties of the plasma.
Moreover, if the unreliability of the perturbative results obtained in the static sector of the mesonic screening masses were confirmed in those new sectors, this will make it clear that the dynamics of the plasma cannot be explained by the knowledge that we have from perturbation theory. We plan to investigate the above mentioned screening masses at 8 different values of temperature, approximately from 3 GeV, up to very high temperature, about 80 GeV.
In order to perform the continuum limit extrapolation, we will take into account 4 different values of the lattice spacing. For this reason, we request computational resources for a total of 50 Mch.