{ "id": "1603.00198", "version": "v1", "published": "2016-03-01T09:30:15.000Z", "updated": "2016-03-01T09:30:15.000Z", "title": "Decomposing highly edge-connected graphs into homomorphic copies of a fixed tree", "authors": [ "Martin Merker" ], "comment": "18 pages", "categories": [ "math.CO" ], "abstract": "The Tree Decomposition Conjecture by Bar\\'at and Thomassen states that for every tree $T$ there exists a natural number $k(T)$ such that the following holds: If $G$ is a $k(T)$-edge-connected simple graph with size divisible by the size of $T$, then $G$ can be edge-decomposed into subgraphs isomorphic to $T$. So far this conjecture has only been verified for paths, stars, and a family of bistars. We prove a weaker version of the Tree Decomposition Conjecture, where we require the subgraphs in the decomposition to be isomorphic to graphs that can be obtained from $T$ by vertex-identifications. We call such a subgraph a homomorphic copy of $T$. This implies the Tree Decomposition Conjecture under the additional constraint that the girth of $G$ is greater than the diameter of $T$. As an application, we verify the Tree Decomposition Conjecture for all trees of diameter at most 4.", "revisions": [ { "version": "v1", "updated": "2016-03-01T09:30:15.000Z" } ], "analyses": { "subjects": [ "05C40", "05C51" ], "keywords": [ "decomposing highly edge-connected graphs", "tree decomposition conjecture", "homomorphic copy", "fixed tree", "natural number" ], "note": { "typesetting": "TeX", "pages": 18, "language": "en", "license": "arXiv", "status": "editable" } } }