{ "id": "1106.3893", "version": "v1", "published": "2011-06-20T13:23:07.000Z", "updated": "2011-06-20T13:23:07.000Z", "title": "Anomalous diffusion for a correlated process with long jumps", "authors": [ "Tomasz Srokowski" ], "comment": "10 pages, 6 figures", "journal": "Physica A 390 (2011) 3077--3085", "doi": "10.1016/j.physa.2011.04.022", "categories": [ "cond-mat.stat-mech" ], "abstract": "We discuss diffusion properties of a dynamical system, which is characterised by long-tail distributions and finite correlations. The particle velocity has the stable L\\'evy distribution; it is assumed as a jumping process (the kangaroo process) with a variable jumping rate. Both the exponential and the algebraic form of the covariance -- defined for the truncated distribution -- are considered. It is demonstrated by numerical calculations that the stationary solution of the master equation for the case of power-law correlations decays with time, but a simple modification of the process makes the tails stable. The main result of the paper is a finding that -- in contrast to the velocity fluctuations -- the position variance may be finite. It rises with time faster than linearly: the diffusion is anomalously enhanced. On the other hand, a process which follows from a superposition of the Ornstein-Uhlenbeck-L\\'evy processes always leads to position distributions with a divergent variance which means accelerated diffusion.", "revisions": [ { "version": "v1", "updated": "2011-06-20T13:23:07.000Z" } ], "analyses": { "keywords": [ "long jumps", "correlated process", "anomalous diffusion", "power-law correlations decays", "algebraic form" ], "tags": [ "journal article" ], "publication": { "journal": "Physica A Statistical Mechanics and its Applications", "year": 2011, "month": "Sep", "volume": 390, "number": "18-19", "pages": 3077 }, "note": { "typesetting": "TeX", "pages": 10, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2011PhyA..390.3077S" } } }