Seminario de Física Teórica ICIMAF
Lugar: ICIMAF, Calle E esq a 15, Vedado
Fecha: Miercoles 1 de Abril, 2pm
Ponente: Wolfgang Bietenholz (Inst. de Fisica, UNAM, Mexico)
Titulo: Measurements with topological restrictions
Resumen: We address models in quantum field theory with topological sectors, and difficulties with their Monte Carlo simulation. In particular we are concerned with the situation where a simulation has an extremely long auto-correlation time with respect to the topological charge. Then reliable numerical measurements are feasible only within individual topological sectors. The challenge is to assemble such restricted measurements to obtain a systematic approximation for the full-fledged result, which would correspond to the correct sampling over the entire set of configurations. Amazingly, under certain conditions this is possible, and it provides in addition an estimate for the topological susceptibility chi_t. We test this scenario, and also an alternative approach to measure chi_t from the topological charge density correlation in a fixed sector.