The extended Burnside ring and module categories
نویسنده
چکیده
In this note an ‘extended Burnside ring’ is defined, generated by classes of semisimple module categories over Rep(G) with quasifibre functors. Here G is a finite group and representations are taken over an algebraically closed field of characteristic 0. It is shown that this is equivalent to a ring generated by centrally extended G-sets and hence the name. Ring homomorphisms into the multiplicative group of the field are computed with an explicit formula and tables of these homomorphisms are given for the groups S4 and S5 which are of particular interest in the context of reductive algebraic groups.
منابع مشابه
Burnside rings
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