arXiv subjects

Alessandro Codello

Publications and source records attributed to Alessandro Codello.

39 records · Page 3Linked to original sources

arXiv2013

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.

cond-mat.stat-mech↗

arXiv2010

Exact Curie temperature for the Ising model on Archimedean and Laves lattices

Using the Feynman-Vdovichenko combinatorial approach to the two dimensional Ising model, we determine the exact Curie temperature for all two dimensional Archimedean lattices. By means of duality, we extend our results to cover all two dimensional Laves lattices. For those lattices where the exact critical temperatures are not exactly known yet, we compare them with Monte Carlo simulations.

cond-mat.stat-mech↗

arXiv2007

Ultraviolet properties of f(R)-Gravity

We discuss the existence and properties of a nontrivial fixed point in f(R)-gravity, where f is a polynomial of order up to six. Within this seven-parameter class of theories, the fixed point has three ultraviolet-attractive and four ultraviolet-repulsive directions; this brings further support to the hypothesis that gravity is nonperturbatively renormalizabile.

hep-th↗