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Abstract

Let n be a positive integer and let B_n be the Artin braid group on
n strands. Further, let B = �ｿｽ�ｿｽ_{n �ｿｽ�ｿｽ 0} B_n+1 be the collection of all
braid groups. The simplicial structure on B is given by face-operators
d_i:B_n�ｿｽ�ｿｽ B_n-1
and degeneracy-operators
s_i:B_n �ｿｽ�ｿｽ B_n+1 for i =1, ..., n.
Specifically, d_i removes the i-th strand from a braid ands_i doubles one.

The main motivation to study the simplicial structure on braid groups
is its relation to homotopy groups of spheres. In the talk we'll discuss
this relation and explore similar simplicial structures on mapping class groups.

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http://www.sci.waseda.ac.jp/campus
�ｿｽ�ｿｽ�ｿｽQ�ｿｽﾆゑｿｽ�ｿｽﾄゑｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽD

For access, see here.

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