Critical fluctuations in normal to superconducting transition

Recent advances in our understanding of critical phenomena due to the application1 of the renormalization group (RG) approach2 are now well known (see, e.g., the textbooks3-5). The scale invariance at the critical point and the universality of certain features of critical phenomena can be explained by RG transformation, and lead to theory which provides a quantitative description of the critical behaviour of various thermodynamic quantities of interest.