MonteCarlo Renormalisation Group for Lattice QCD.
Abstract
The properties of the SU(2) and SU(3) lattice gauge theories are investigated using the Real Space Monte Carlo Renormalisation Group method. The "SQRT.(3 block transformation" is found to be very efficient in this analysis. The nonperturbative (beta)function is calculated for the SU(2) lattice gauge theory over a large range of couplings and along both the Wilson axis and the MigdalKadanoff improved action line. A possible explanation of the observed nonperturbative features of the (beta)function is given. The same data sample is used to calculate the improved action needed for better numerical simulations, and the results are compared with those obtained using the MigdalKadanoff approximate renormalisation and Symanzik's perturbative improvement approach. A similar but less extensive analysis is done for the SU(3) lattice gauge theory as well. The results indicate that even for the pure gauge theory, the present day MonteCarlo calculations are far from establishing an agreement with the expected asymptotic scaling. However, an improved action approach, combined with the (beta)function determined using the MonteCarlo Renormalisation Group technique, should make it possible to convincingly demonstrate the scaling behaviour in near future.
 Publication:

Ph.D. Thesis
 Pub Date:
 1984
 Bibcode:
 1984PhDT........59P
 Keywords:

 Physics: Elementary Particles and High Energy