Combining MCRG and Fourier accelerated Langevin algorithm

We study the implementation of Monte Carlo renormalization group (MCRG) in momentum space. This technique is most efficient when used in combination with a Fourier accelerated Langevin algorithm. As a benchmark we calculate the critical exponents ν and η in the vicinity of both the gaussian and the Wilson fixed point in λφ34. The results are very competitive with alternative analytical methods and require a moderate computational effort only.