{ "id": "2010.07953", "version": "v1", "published": "2020-10-15T18:00:21.000Z", "updated": "2020-10-15T18:00:21.000Z", "title": "Stochastic Fractal and Noether's Theorem", "authors": [ "Rakibur Rahman", "Fahima Nowrin", "M. Shahnoor Rahman", "Jonathan A. D. Wattis", "Md. Kamrul Hassan" ], "comment": "11 pages, 6 captioned figures each containing 2 subfigures", "categories": [ "cond-mat.stat-mech", "hep-th", "quant-ph" ], "abstract": "We consider the binary fragmentation problem in which, at any breakup event, one of the daughter segments either survives with probability $p$ or disappears with probability $1\\!-\\!p$. It describes a stochastic dyadic Cantor set that evolves in time, and eventually becomes a fractal. We investigate this phenomenon, through analytical methods and Monte Carlo simulation, for a generic class of models, where segment breakup points follow a symmetric beta distribution with shape parameter $\\alpha$, which also determines the fragmentation rate. For a fractal dimension $d_f$, we find that the $d_f$-th moment $M_{d_f}$ is a conserved quantity, independent of $p$ and $\\alpha$. We use the idea of data collapse -- a consequence of dynamical scaling symmetry -- to demonstrate that the system exhibits self-similarity. In an attempt to connect the symmetry with the conserved quantity, we reinterpret the fragmentation equation as the continuity equation of a Euclidean quantum-mechanical system. Surprisingly, the Noether charge corresponding to dynamical scaling is trivial, while $M_{d_f}$ relates to a purely mathematical symmetry: quantum-mechanical phase rotation in Euclidean time.", "revisions": [ { "version": "v1", "updated": "2020-10-15T18:00:21.000Z" } ], "analyses": { "keywords": [ "noethers theorem", "stochastic fractal", "stochastic dyadic cantor set", "conserved quantity", "monte carlo simulation" ], "note": { "typesetting": "TeX", "pages": 11, "language": "en", "license": "arXiv", "status": "editable" } } }