Heat Equation from Exact Renormalization Group Equation (ERGE) at Local Potential Approximation (LPA)

By simply applying the Local Potential Approximation (LPA) on the Polchinski’s Exact Renormalization Group (ERG) flow equation for single Bosonic and spinless Fermionic fields, and initially considering only the coarse-graining (blocking) aspect of Wilson’s Renormalization Group program. Within the LPA limit the Polchinski’s ERG flow equation simplifies into a heat differential equation for both Bosonic and Fermionic fields. Solving the differential equations leads to logarithmic interactions (logarithmic vertex function) in both Bosonic and Fermionic fields at their fixed points.