Aspects of gauge theories with few and many fermion flavors
Dr. Jens Braun (TU Darmstadt)

The existence of universal behavior plays a very important role in modern physics since it allows us to classify theories according to their scaling behavior close to a critical point. In this talk, we analyze the scaling behavior of physical observables in strongly-flavored asymptotically free gauge theories. Such theories approach a quantum critical point when the number of fermion flavors is increased. Close to this critical point, physical observables then exhibit an exponential scaling behavior, provided the gauge coupling is considered as a constant (external) parameter. We discuss how this exponential scaling behavior is modified when the scale dependence of the gauge coupling is taken into account. In particular, we present estimates for the size of the regime with an exponential scaling behavior in QCD with \(N_f\) fermion flavors and \(N_c\) colors. Our results suggest that the corrections to this exponential behavior might be relevant for the analysis of lattice QCD data.