{ "id": "1211.4303", "version": "v3", "published": "2012-11-19T05:07:26.000Z", "updated": "2014-09-26T08:37:06.000Z", "title": "Rational functions with identical measure of maximal entropy", "authors": [ "Hexi Ye" ], "comment": "2 figures, 21 pages", "categories": [ "math.DS" ], "abstract": "We discuss when two rational functions $f$ and $g$ can have the same measure of maximal entropy. The polynomial case was completed by (Beardon, Levin, Baker-Eremenko,Schmidt-Steinmetz, etc., 1980s-90s), and we address the rational case following Levin-Przytycki (1997). We show: $\\mu_f = \\mu_g$ implies that $f$ and $g$ share an iterate ($f^n = g^m$ for some $n$ and $m$) for general $f$ with degree $d \\geq 3$. And for generic $f\\in \\Rat_{d\\geq 3}$, $\\mu_f = \\mu_g$ implies $g=f^n$ for some $n \\geq 1$. For generic $f\\in \\Rat_2$, $\\mu_f = \\mu_g$ implies that $g= f^n$ or $\\sigma_f\\circ f^n$ for some $n\\geq 1$, where $\\sigma_f\\in PSL_2(\\C)$ permutes two points in each fiber of $f$. Finally, we construct examples of $f$ and $g$ with $\\mu_f = \\mu_g$ such that $f^n \\neq \\sigma\\circ g^m$ for any $\\sigma \\in PSL_2(\\C)$ and $m,n\\geq 1$.", "revisions": [ { "version": "v2", "updated": "2012-12-16T03:12:09.000Z", "journal": null, "doi": null }, { "version": "v3", "updated": "2014-09-26T08:37:06.000Z" } ], "analyses": { "keywords": [ "rational functions", "maximal entropy", "identical measure", "polynomial case", "rational case" ], "note": { "typesetting": "TeX", "pages": 21, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2012arXiv1211.4303Y" } } }