Ramanujan Auditorium

Supercomputing the properties of strong interaction matter

Frithjof Karsch

Bielefeld University

Strongly interacting matter at temperatures more than 100000 times
larger than in the interior of our sun and at an order of magnitude larger
densities than in atomic nuclei existed in the early universe and is studied
today experimentally on earth in ultra-relativistic collisions of heavy-ions.

The exploration of properties of such hot and dense matter also is subject
to intensive theoretical research. Computer simulations of the theory of
strong interactions, Quantum Chromodynamics (QCD), performed on discrete
space-time lattices provide a powerful framework for the study of such matter.
These simulations provide inside into the phase structure of strong interaction
matter described by QCD and allow first principle calculations that can be
confronted with experimental results obtained in heavy-ion collisions.

We give a brief overview of the development of lattice QCD calculations at
finite temperature and density and discuss computational requirements for
state-of-the-art numerical calculations. We furthermore present results from
studies of the chiral phase transition in QCD as well as a new, high statistics
determination of the QCD equation of state. Some results on fluctuations of
conserved charges and their higher order cumulants will be discussed and
compared with experimental results.