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We study the conformation and scaling properties of a self-avoiding fluid membrane, subject to an osmotic pressure $p$, by means of Monte Carlo simulations. Using finite size scaling methods in combination with a histogram reweighting techniques we find that the surface undergoes an abrupt conformational transition at a critical pressure $p^ast$, from low pressure deflated configurations with a branched polymer characteristics to a high pressure inflated phase, in agreement with previous findings cite{gompper,baum}. The transition pressure $p^{ast}$ scales with the system size as $p^ast propto N^{-alpha}$, with $alpha = 0.69 pm 0.01$. Below $p^ast$ the enclosed volume scales as $V propto N$, in accordance with the self-avoiding branched polymer structure, and for $psearrow p^{ast}$ our data are consistent with the finite size scaling form $V propto N^{beta_{+}}$, where $beta_{+} = 1.43 pm 0.04$. Also the finite size scaling behavior of the radii of gyration and the compressibility moduli are obtained. Some of the observed exponents and the mechanism behind the conformational collapse are interpreted in terms of a Flory theory.
A new Monte Carlo approach is proposed to investigate the fluid-solid phase transition of the polydisperse system. By using the extended ensemble, a reversible path was constructed to link the monodisperse and corresponding polydisperse system. Once
The Widom-Rowlinson model of a fluid mixture is studied using a new cluster algorithm that is a generalization of the invaded cluster algorithm previously applied to Potts models. Our estimate of the critical exponents for the two-component fluid are
We perform Monte-Carlo simulations to study the Bernoulli ($p$) bond percolation on the enhanced binary tree which belongs to the class of nonamenable graphs with one end. Our numerical results show that the system has two different percolation thres
The diffuse extragalactic gamma-ray background (EGRB) has been derived by various groups from observations by the Energetic Gamma Ray Experiment Telescope (EGRET) instrument on the Compton Gamma Ray Observatory (CGRO). The derived EGRB consists of ga
We study antiferromagnetic spin--1/2 Heisenberg ladders, comprised of $n_c$ chains ($2 leq n_c leq 6$) with ratio $J_{bot}/J_{|}$ of inter-- to intra--chain couplings. From measurements of the correlation function we deduce the correlation length $xi