English

Parallel Algorithm and Dynamic Exponent for Diffusion-limited Aggregation

comp-gas 2016-08-31 v2 Statistical Mechanics Cellular Automata and Lattice Gases

Abstract

A parallel algorithm for ``diffusion-limited aggregation'' (DLA) is described and analyzed from the perspective of computational complexity. The dynamic exponent z of the algorithm is defined with respect to the probabilistic parallel random-access machine (PRAM) model of parallel computation according to TLzT \sim L^{z}, where L is the cluster size, T is the running time, and the algorithm uses a number of processors polynomial in L\@. It is argued that z=D-D_2/2, where D is the fractal dimension and D_2 is the second generalized dimension. Simulations of DLA are carried out to measure D_2 and to test scaling assumptions employed in the complexity analysis of the parallel algorithm. It is plausible that the parallel algorithm attains the minimum possible value of the dynamic exponent in which case z characterizes the intrinsic history dependence of DLA.

Cite

@article{arxiv.comp-gas/9609001,
  title  = {Parallel Algorithm and Dynamic Exponent for Diffusion-limited Aggregation},
  author = {K. Moriarty and J. Machta and R. Greenlaw},
  journal= {arXiv preprint arXiv:comp-gas/9609001},
  year   = {2016}
}

Comments

24 pages Revtex and 2 figures. A major improvement to the algorithm and smaller dynamic exponent in this version