Embeddings of trees in the hyperbolic disk
Embeddings of trees in the hyperbolic disk
复制标题
双曲盘中树的嵌入
DOI:
10.1080/17476939408814723
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发表时间:
1994
期刊:
影响因子:
--
通讯作者:
Flavia Colonna
中科院分区:
文献类型:
--
作者:
Joel M. Cohen;Flavia Colonna
We consider the conditions under which a homogeneous tree of even degree (i.e. the Cayley graph of a free group) may be embedded in the hyperbolic disk in such a way that the automorphisms induced by rotation and by translation by group elements may be represented by automorphisms of the disk. We concentrate on the study of a particular optimal such embedding. We show that in this case bounded analytic functions on the disk are determined by their values at the vertices of the embedded tree. Using a construction of we can define harmonicity on a homogeneous tree in such a way that bounded functions on the disk restrict to harmonic functions on the tree if and only if they are harmonic. We also show a simple and elegant construction of this tree.