Critical fluctuations and complex spinodal points

The experimental signatures of the QCD critical point rely on the universal singular behavior of the equation of state at the critical point. Therefore, we study singularities of the universal scaling equation of state of the f4 theory, or the Ising model. We focus on the relation between spinodal points that limit the domain of metastability for temperatures below the critical temperature, i.e., T < Tc, and Lee-Yang edge singularities that limit the domain of analyticity around the point of zero magnetic field H for T > Tc. The extended analyticity conjecture (due to Fonseca and Zamolodchikov) that for T 4 where the equation of state of the f4 theory is expected to become mean-field-like. We derive the Ginzburg criterion that determines the size of the region around the Lee-Yang edge singularity, where the mean-field theory no longer applies