Cohomology of Artin groups of type Ãn , Bn and applications
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چکیده
We consider two natural embeddings between Artin groups: the group GÃn−1 of type Ãn−1 embeds into the group GBn of type Bn ; GBn in turn embeds into the classical braid group Brn+1 := GAn of type An . The cohomologies of these groups are related, by standard results, in a precise way. By using techniques developed in previous papers, we give precise formulas (sketching the proofs) for the cohomology of GBn with coefficients over the module Q[q±1, t±1], where the action is (−q)–multiplication for the standard generators associated to the first n− 1 nodes of the Dynkin diagram, while is (−t)–multiplication for the generator associated to the last node.
منابع مشابه
Cohomology of Affine Artin Groups and Applications
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تاریخ انتشار 2008