{ "id": "0810.1673", "version": "v3", "published": "2008-10-09T15:47:19.000Z", "updated": "2010-05-02T14:20:18.000Z", "title": "Topology of Fatou components for endomorphisms of CP^k: Linking with the Green's Current", "authors": [ "Suzanne Lynch Hruska", "Roland K. W. Roeder" ], "comment": "Revision 3: Added improvements to the discussion of skew products. 21 pages. Comments welcome", "categories": [ "math.DS", "math.GT" ], "abstract": "Little is known about the global topology of the Fatou set $U(f)$ for holomorphic endomorphisms $f: \\mathbb{CP}^k \\to \\mathbb{CP}^k$, when $k >1$. Classical theory describes $U(f)$ as the complement in $ \\mathbb{CP}^k$ of the support of a dynamically-defined closed positive $(1,1)$ current. Given any closed positive $(1,1)$ current $S$ on $ \\mathbb{CP}^k$, we give a definition of linking number between closed loops in $\\mathbb{CP}^k \\setminus \\supp S$ and the current $S$. It has the property that if $lk(\\gamma,S) \\neq 0$, then $\\gamma$ represents a non-trivial homology element in $H_1(\\mathbb{CP}^k \\setminus \\supp S)$. As an application, we use these linking numbers to establish that many classes of endomorphisms of $\\mathbb{CP}^2$ have Fatou components with infinitely generated first homology. For example, we prove that the Fatou set has infinitely generated first homology for any polynomial endomorphism of $\\mathbb{CP}^2$ for which the restriction to the line at infinity is hyperbolic and has disconnected Julia set. In addition we show that a polynomial skew product of $\\mathbb{CP}^2$ has Fatou set with infinitely generated first homology if some vertical Julia set is disconnected. We then conclude with a section of concrete examples and questions for further study.", "revisions": [ { "version": "v3", "updated": "2010-05-02T14:20:18.000Z" } ], "analyses": { "subjects": [ "37F20", "37F45", "32Q55", "32H50" ], "keywords": [ "fatou components", "infinitely generated first homology", "greens current", "fatou set", "julia set" ], "note": { "typesetting": "TeX", "pages": 21, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2008arXiv0810.1673L" } } }