We study the phase diagram of the site-diluted Ising model in a wide dilution range, through Monte Carlo simulations and Finite-Size Scaling techniques. Our results for the critical exponents and universal cumulants turn out to be dilution-independent, but only after a proper infinite volume ex-trapolation, taking into account the leading… (More)
Using Finite-Size Scaling techniques we obtain accurate results for critical quantities of the Ising model and the site percolation, in three dimensions. We pay special attention in parameterizing the corrections-to-scaling, what is necessary to put the systematic errors below the statistical ones.
INTRODUCTION The bones of the skull of the newborn and nursing infants, in general, possess great malleability. For this reason, the depressed fractures occurring at this age are called "Ping Pong" or "Green Stick" fractures. The treatment of these fractures is surgical according to different authors, although some of these fractures that happen in… (More)
Using finite-size scaling methods we measure the thermal and magnetic exponents of the site percolation in four dimensions, obtaining a value for the anomalous dimension very different from the results found in the literature. We also obtain the leading corrections-to-scaling exponent and, with great accuracy, the critical density.
The Hybrid Monte Carlo algorithm is adapted to the simulation of a system of classical degrees of freedom coupled to non self-interacting lattices fermions. The diagonalization of the Hamiltonian matrix is avoided by introducing a path-integral formulation of the problem, in d + 1 Euclidean space-time. A perfect action formulation allows to work on the… (More)
Using finite-size scaling techniques, we study the critical properties of the site-diluted Ising model in four dimensions. We carry out a high statistics Monte Carlo simulation for several values of the dilution. The results support the perturbative scenario: there is only the Ising fixed point with large logarithmic scaling corrections. We obtain , using… (More)
We present the results of a Monte Carlo simulation of the RP 2 model in three dimensions with negative coupling. We observe a second order phase transition between the disordered phase and an anti-ferromagnetic, unfrustrated, ordered one. We measure, with a Finite Size Scaling analysis, the thermal exponent, obtaining ν = 0.784(8). We have found two… (More)
We present Tethered Monte Carlo, a simple, general purpose method of computing the effective potential of the order parameter (Helmholtz free energy). This formalism is based on a new statistical ensemble, closely related to the micromagnetic one, but with an extended configuration space (through Creutz-like demons). Canonical averages for arbitrary values… (More)
Critical exponents and unusual properties of the broken phase in the 3d-RP 2 antiferromagnetic model. We present the results of a Monte Carlo simulation of the antiferromagnetic RP 2 model in three dimensions. With finite-size scaling techniques we accurately measure the critical exponents and compare them with those of O(N) models. We are able to… (More)