Enhancement of photon emission rate near QCD critical point

We compute photon emission rate enhancement near the QCD critical point using an effective theory of dynamic critical phenomena and derive a universal photon spectrum. The emission rate scales similarly to conductivity, increasing with the correlation length ($\xi$), diverging at the critical point. The spectrum exhibits $\omega dN_{\gamma}/d^3k \propto \omega^{-1/2}$ in the scaling regime, with the transition occurring at a frequency comparable to shear damping rate $\omega \sim \gamma_{\eta}/\xi^2$, reflecting the nonequilibrium properties of the near-critical liquid.