Information optimization for Monte Carlo data and application to high-temperature quantum chromodynamics

The method of density of states is applied to the problem of simulating quantum chromodynamics (QCD). Particular emphasis is placed on the computation of the equation of state describing the thermodynamics of QCD. The use of density of states reconstruction in QCD is one of the most severe tests of the method so far, as QCD involves one to two orders of magnitude more degrees of freedom than current spin models and other systems of statistical mechanics. The method of density of states reconstruction is summarized in general terms and its usefulness is illustrated with examples from finite temperature QCD. It is shown that, by using the method of density of states, one can optimize the information obtained from limited simulations in order to obtain in the worst cases the derivative of the thermodynamical functions, and in the best cases their entire curve over a wide range of temperatures