“Deflation of permutation sets”

 

 

 

by

 

LAURENCE BARKER

(BILKENT UNIVERSITY)

 

 

Abstract: In terms of the idempotents of the Burnside ring, the actions of isogation, induction, restriction and inflation are fairly straightforward, but the formula for deflation has some peculiar combinatorics involving the Moebius function of the given group. Despite their apparent peculiarity, the deflation numbers are important: they appear in the formulas for the exponential and Tornehave morphisms. Furthermore, the simple composition factors of the Burnside functor are paramatrized by those finite groups whose non-trivial
deflation numbers are all zero; it is not known explicitly which groups satisfy that condition.

 

 

 

 

 

 

 

Date : April 1, 2009 (Wednesday)

Time : 13:40-14:30

Place: Room SAZ01