Speaker:

Miguel Zilhao (CENTRA, IST)

Abstract:

Understanding the dynamics of out-of-equilibrium matter in strongly coupled systems is an important and challenging problem in theoretical physics. A particularly interesting example is the Quark-Gluon Plasma formed in relativistic colliders such as RHIC or the LHC, which motivates the study of the relaxation process in strongly coupled non-abelian field theories. In this talk it will be shown how we use holography to map the dynamics of a non-conformal gauge theory to a gravitational system, and the strategy we use to numerically evolve Einstein's equations. With these tools, we can perform holographic Heavy Ion collisions at different energies in gauge theories with different degrees of non-conformality, and analyse corresponding relaxation times. We will also see how we can study the spinodal instability of a four-dimensional, strongly-coupled gauge theory with a first-order thermal phase transition by

evolving the dual gravitational description, which is afflicted by a Gregory-Laflamme instability. We numerically evolve Einstein's equations to follow the instability until the system settles down to some stationary, inhomogeneous black brane, and show that the time evolution of the instability and the final states are accurately described by second-order hydrodynamics.