{ "id": "1110.6125", "version": "v2", "published": "2011-10-27T15:51:37.000Z", "updated": "2012-10-04T16:39:38.000Z", "title": "On conjugations of circle homeomorphisms with two break points", "authors": [ "Habibulla Akhadkulov", "Akhtam Dzhalilov", "Dieter Mayer" ], "comment": "16 pages, 2 figures, to appear in Ergodic Theory and Dynamical Systems", "doi": "10.1017/etds.2012.159", "categories": [ "math.DS" ], "abstract": "Let $f_i\\in C^{2+\\alpha}(S^1\\setminus \\{a_i,b_i\\}), \\alpha >0, i=1,2$ be circle homeomorphisms with two break points $a_i,b_i$, i.e. discontinuities in the derivative $f_i$, with identical irrational rotation number $rho$ and $\\mu_1([a_1,b_1])= \\mu_2([a_2,b_2])$, where $\\mu_i$ are invariant measures of $f_i$. Suppose the products of the jump ratios of $Df_1$ and $Df_2$ do not coincide, i.e. $\\frac{Df_1(a_1-0)}{Df_1(a_1+0)}\\times \\frac{Df_1(b_1-0)}{Df_1(b_1+0)}\\neq \\frac{Df_2(a_2-0)}{Df_2(a_2+0)}\\times \\frac{Df_2(b_2-0)}{Df_2(b_2+0)}$. Then the map $\\psi$ conjugating $f_1$ and $f_2$ is a singular function, i.e. it is continuous on $S^1$, but $D\\psi = 0$ a.e. with respect to Lebesgue measure", "revisions": [ { "version": "v2", "updated": "2012-10-04T16:39:38.000Z" } ], "analyses": { "subjects": [ "37E10", "37C15", "37C40" ], "keywords": [ "circle homeomorphisms", "break points", "conjugations", "identical irrational rotation number", "invariant measures" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 16, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2011arXiv1110.6125A" } } }