Dynamic Renormalization Group Study of the φ⁴ Model with Colored Noise

The non-conserved $\phi^4$ model defined by a Langevin equation with external non-white noise is studied by means of the Dynamic Renormalization Group. The correlation time of the noise changes the critical point location but does not affect the critical exponents up to order $\varepsilon^2$. The same effect is obtained when the correlation length of the noise is considered. These results are shown to be in agreement with previous numerical simulations.