Nuclear Physics & RIKEN Theory Seminar

Two Lattice Boltzmann (LB) formulations to solve the relativistic Boltzmann equation are pre- sented. The first method is numerically validated and applied to the propagation of shock-wave in quark-gluon plasmas and the impact of a supernova blast-wave on massive interstellar clouds. The simulations of shock waves are performed in the low and high viscosities regime, using three different computational models, the relativistic lattice Boltzmann (RLB), the Boltzmann Approach Multi- Parton Scattering (BAMPS), and the viscous sharp and smooth transport algorithm (vSHASTA). From the comparison of the results, we conclude that the RLB model departs from BAMPS in the case of high speeds and high temperature (viscosities), the departure being due to the fact that the RLB is based on a quadratic approximation of the Maxwell-Ju ̈ttner distribution, which is only valid for sufficiently low temperature and velocity. Finally, the second method, which is a fully relativistic version of the previous one, is briefly described showing that is capable to handle general geometries and ultrarelativistic cases.