Talk:Replica trick

General formulation

Is it possible to elaborate on the meaning of the terms in the third equation in this section, $\textstyle \int dJ_{ij}e^{-\beta J-\alpha J^{2}}$, to clarify what e.g. α and J² mean any how/why they have appeared? More generally, is it possible to make this section self-contained? Some concepts (and even variable names) are introduced without being defined, or without linking to a wiki page that defines them using the same notation.