Monte Carlo Dynamical Renormalization Group Approach to the Critical Nature of a Sandpile

碩士 === 國立中正大學 === 物理所 === 93 === The dynamically driven renormalization group (DDRG) approach for a sandpile is based on the similarity of dynamical part for all relaxation events between a cell and a site. Follow the idea of DDRG, we classify a relaxation event on a RG cell being static or dynamica...

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Bibliographic Details
Main Authors: Eason Chen, 陳貽聖
Other Authors: none
Format: Others
Language:zh-TW
Published: 2005
Online Access:http://ndltd.ncl.edu.tw/handle/49048955232873406157
Description
Summary:碩士 === 國立中正大學 === 物理所 === 93 === The dynamically driven renormalization group (DDRG) approach for a sandpile is based on the similarity of dynamical part for all relaxation events between a cell and a site. Follow the idea of DDRG, we classify a relaxation event on a RG cell being static or dynamical by the toppling number g. Replacing to count a huge number of dynamical events, we propose a Monte Carlo procedure to simplify RG calculations. This RG scheme allows us to investigate the effect of g. In addition, two important dynamics, the grain redistribution and multiple topplings, are also considered.Our result of avalanche exponent on the 3*3 square cell shows that the multiple topplings is important and the redistribution effect can be omitted. Furthermore, through choosing a proper value of g (~5.7 or 4.6 for considering multiple topplings or not, respectively), both height probabilities and avalanche exponent arrive at the predicted values simultaneously