"Dropping rho and A1 Meson Masses at Chiral Phase Transition in the Generalized Hidden Local Symmetry"

I will talk on the recent analysis, done in collaboration with Chihiro Sasaki, in which we study the chiral symmetry restoration using the generalized hidden local symmetry (GHLS) that incorporates the rho and A1 mesons as the gauge bosons of the GHLS and the pion as the Nambu-Goldstone boson consistently with the chiral symmetry of QCD. We show that a set of parameter relations, which ensures the first and second Weinberg's sum rules, is invariant under the renormalization group evolution. Then, we found that the Weinberg's sum rules together with the matching of the vector and axial-vector current correlators inevitably leads to the dropping masses of both rho and A1 mesons at the symmetry restoration point, and that the mass ratio as well as the mixing angle between the pion and A1 meson flows into one of three fixed points.