Current Topics Seminar
| Speaker | Andrew Crites |
| Title | Affine permutations and pattern avoidance |
| Date | January 27 4:00pm PDL C-36 |
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In this talk I will introduce some of the combinatorics
behind affine permutations. These are a generalization of classical
permutations that, when viewed as a reflection group, amount to adding
an affine reflection to the set of generators (hence the name). We
now end up with an infinite group, however, many of the same results
from classical permutations still hold. Classifying families of
permutations in terms of the patterns they avoid has been studied for
a long time. However, applying pattern avoidance to affine
permutations is fairly new. I will discuss pattern avoidance, and in
particular, the role it plays in the geometry of the corresponding
affine Schubert varieties. Part of this talk is joint work with Sara
Billey.
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