Monte Carlo without chains

Monte Carlo without Chains Alexandre J. Chorin Department of Mathematics, University of California and Lawrence Berkeley National Laboratory Berkeley, CA 94720 Abstract A sampling method for spin systems is presented. The spin lattice is written as the union of a nested sequence of sublattices, all but the last with conditionally independent spins, which are sampled in succession using their marginals. The marginals are computed concurrently by a fast algorithm; errors in the evaluation of the marginals are offset by weights. There are no Markov chains and each sample is independent of the previous ones; the cost of a sample is proportional to the number of spins (but the number of samples needed for good statistics may grow with array size). The examples include the Edwards-Anderson spin glass in three dimensions. Keywords: Monte Carlo, no Markov chains, marginals, spin glass Introduction. Monte Carlo sampling in physics is synonymous with Markov chain Monte Carlo (MCMC) for good reasons which are too well-known to need repeating (see e.g. [2],[17]). Yet there are problems where the free energy landscape exhibits multi- ple minima and the number of MCMC steps needed to produce an independent sample is huge; this happens for example in spin glass models (see e.g. [13],[16]). It is therefore worthwhile to consider alternatives, and the purpose of the present paper is to propose one. An overview of the proposal is as follows: Consider a set of variables (“spins”) located at the nodes of a lattice L with a probability density P that one wishes to sample. Suppose one can construct a nested sequences of subsets L 0 ⊃ L 1 ⊃ · · · ⊃ L n with the following properties: L 0 = L; L n contains few points; the marginal density of the variables in each L i is known, and given values of the spins in L i+1 , the remaining variables in L i are independent. Then the following is an effective sampling strategy for the spins in L: First sample the spins in L n so that each configuration is sampled with a frequency equal to its probability by first listing all the states of the spins in L n and calculating their probabilities. Then sample the variables in each L i−1 as i decreases from n − 1 to zero using the independence of these variables, making sure that each state is visited with a frequency equal to its probability. Each state of L = L 0 is then

[1]  Goodman,et al.  Multigrid Monte Carlo method. Conceptual foundations. , 1989, Physical review. D, Particles and fields.

[2]  M. Talagrand,et al.  Spin Glasses: A Challenge for Mathematicians , 2003 .

[3]  A. Chorin Hermite expansions in Monte-Carlo computation , 1971 .

[4]  A. Fisher,et al.  The Theory of Critical Phenomena: An Introduction to the Renormalization Group , 1992 .

[5]  M. Mézard,et al.  Spin Glass Theory and Beyond , 1987 .

[6]  Wang,et al.  Nonuniversal critical dynamics in Monte Carlo simulations. , 1987, Physical review letters.

[7]  Achi Brandt,et al.  Inverse Monte Carlo renormalization group transformations for critical phenomena. , 2002, Physical review letters.

[8]  Helmut G. Katzgraber,et al.  Universality in three-dimensional Ising spin glasses: A Monte Carlo study , 2006, cond-mat/0602212.

[9]  K. Binder,et al.  The Monte Carlo Method in Condensed Matter Physics , 1992 .

[10]  Alexandre J. Chorin,et al.  Optimal prediction with memory , 2002 .

[11]  D. Ron,et al.  Renormalization Multigrid (RMG): Statistically Optimal Renormalization Group Flow and Coarse-to-Fine Monte Carlo Acceleration , 2001 .

[12]  C. L. Ullod,et al.  Critical behavior of the three-dimensional Ising spin glass , 2000 .

[13]  Kurt Binder,et al.  Critical Properties from Monte Carlo Coarse Graining and Renormalization , 1981 .

[14]  A. Chorin,et al.  Stochastic Tools in Mathematics and Science , 2005 .

[15]  A. Fisher,et al.  The Theory of critical phenomena , 1992 .

[16]  F. Guerra Spin Glasses , 2005, cond-mat/0507581.

[17]  Paul C. Martin Statistical Physics: Statics, Dynamics and Renormalization , 2000 .

[18]  Riccardo Zecchina,et al.  Survey propagation: An algorithm for satisfiability , 2002, Random Struct. Algorithms.

[19]  Alexandre J. Chorin Conditional Expectations and Renormalization , 2003, Multiscale Model. Simul..

[20]  Jonathan Weare,et al.  Efficient Monte Carlo sampling by parallel marginalization , 2007, Proceedings of the National Academy of Sciences.

[21]  Anton Bovier,et al.  Mathematical Aspects of Spin Glasses and Neural Networks , 1997 .

[22]  M. Talagrand Spin glasses : a challenge for mathematicians : cavity and mean field models , 2003 .

[23]  Panagiotis Stinis,et al.  A maximum likelihood algorithm for the estimation and renormalization of exponential densities , 2005 .

[24]  R. Monasson,et al.  Rigorous decimation-based construction of ground pure states for spin-glass models on random lattices. , 2002, Physical review letters.

[25]  R. Swendsen Monte Carlo renormalization-group studies of the d=2 Ising model , 1979 .

[26]  Tim Hesterberg,et al.  Monte Carlo Strategies in Scientific Computing , 2002, Technometrics.

[27]  M. Mézard,et al.  Survey propagation: An algorithm for satisfiability , 2005 .

[28]  D. Haar,et al.  Statistical Physics , 1971, Nature.

[29]  Moore,et al.  Critical behavior of the three-dimensional Ising spin glass. , 1985, Physical review. B, Condensed matter.