Critical behavior of isotropic systems with strong dipole-dipole interaction: Three-loop study

We analyze the critical behavior of isotropic systems with dipole-dipole interaction by renormalization-group methods in fixed space-time dimensions. Working in three-dimensional theory we analytically find three-loop expressions for critical exponents in the limit of dominating dipole-dipole forces. Resummation of the series obtained provides numerical values close to O(3)-theory predictions, justifying the applicability of such a simplified model to systems with strong dipole-dipole interaction.