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The universality of Hom complexes

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 نشر من قبل Anton Dochtermann
 تاريخ النشر 2007
  مجال البحث
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 تأليف Anton Dochtermann




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It is shown that if T is a connected nontrivial graph and X is an arbitrary finite simplicial complex, then there is a graph G such that the complex Hom(T,G) is homotopy equivalent to X. The proof is constructive, and uses a nerve lemma. Along the way several results regarding Hom complexes, exponentials, and subdivision are established that may be of independent interest.



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