New techniques for finite density lattice field theory
In recent years new ideas for overcoming the complex action problem of finite density lattice field theories were developed. For several models a reformulation in terms of new degrees of freedom, so-called dual variables, leads to a partition sum that has only real and positive contributions, such that Monte Carlo simulations become possible. The results can be used to assess other recently developed techniques such as fugacity and modified Taylor expansions. I give an overview over the dual variables approach and discuss the comparison with the series expansions.