Mass gap in compact U(1) Model in (2+1) dimensions

A numerical study of low-lying glueball masses of compact U(1) lattice gauge theory in (2+1) dimensions is performed using Standard Path integral Monte Carlo techniques. The masses are extracted, at fixed (low) temperature, from simulations on anisotropic lattices, with temporal lattice spacing much smaller than the spatial ones. Convincing evidence of the scaling behaviour in the antisymmetric mass gap is observed over the range $1.4<\beta <2.25$. The observed behaviour is very consistent with asymptotic form predicted by G{\" o}pfert and Mack. Extrapolations are made to the "Hamiltonian" limit, and the results are compared with previous estimates obtained by many other Hamiltonian studies.