Anton Rebhan

Experimentally, there is now a wealth of data from the relativistic heavy-ion collider RHIC at BNL (Brookhaven, USA) that indicates that a new state of strongly-interacting matter, the quark-gluon plasma, has been produced which shows strong collective behaviour, much stronger in fact than previously envisaged. This is now being followed up at an order-of-magnitude higher energies by a heavy-ion program at CERN using the LHC, both at dedicated experiments (ALICE) and also at the CMS experiment, in which HEPHY is participating. These theoretical studies will also be relevant for future experiments at the FAIR facility in GSI Darmstadt.

The group of Rebhan and collaborators has recognized expertise in resummations of thermal perturbation theories applied to the thermodynamics of the quark-gluon plasma at temperatures a few times the deconfinement temperature, as well as at low temperatures but large quark chemical potential.

In the context of nonequilibrium dynamics, nonabelian plasma instabilities have been identified as a novel and crucial ingredient, and the world-wide first systematic studies have been performed by the group of Rebhan and collaborators using so-called hard-loop effective theories.

A new theoretical approach to all of the above issues involves a so-called duality of strongly coupled gauge theories with gravity in 5-dimensional Anti-de Sitter space (the so-called AdS/CFT correspondence and generalizations thereof, bringing together the theory of gravitational interactions and of strong interactions, also with theoretical spin-off to other strongly coupled systems such as cold atoms in the unitary limit.

Successful applications studied by the group of Rebhan involve quark-gluon plasma near the deconfinement transition and also new ways to study non-equilibrium phenomenona such as spatial anisotropies.

On a more formal level, the group of Rebhan – in collaboration with colleagues from Stony Brook University (New York) – has made important contributions to the calculation of quantum corrections to solitons in supersymmetric field theories.