Renormalization Group Flow of Hexatic Membranes

We investigate hexatic membranes embedded in Euclidean D-dimensional space using a reparametrization invariant formulation combined with exact renormalization group (RG) equations. An XY-model coupled to a fluid membrane, when integrated out, induces long-range interactions between curvatures described by a Polyakov term in the effective action. We evaluate the contributions of this term to the running surface tension, bending and Gaussian rigidities in the approximation of vanishing disclination (vortex) fugacity. We find a non-Gaussian fixed-point where the membrane is crinkled and has a non-trivial fractal dimension.