English

The equivariant Euler characteristic of real Coxeter toric varieties

Representation Theory 2009-07-17 v2

Abstract

Let WW be a Weyl group, and let \CTW\CT_W be the complex toric variety attached to the fan of cones corresponding to the reflecting hyperplanes of WW, and its weight lattice. The real locus \CTW(R)\CT_W(\R) is a smooth, connected, compact manifold with a WW-action. We give a formula for the equivariant Euler characteristic of \CTW(R)\CT_W(\R) as a generalised character of WW. In type An1A_{n-1} for nn odd, one obtains a generalised character of \Symn\Sym_n whose degree is (up to sign) the nthn^{\text{th}} Euler number.

Keywords

Cite

@article{arxiv.0806.0680,
  title  = {The equivariant Euler characteristic of real Coxeter toric varieties},
  author = {Anthony Henderson and Gus Lehrer},
  journal= {arXiv preprint arXiv:0806.0680},
  year   = {2009}
}

Comments

10 pages. Version 2 incorporates slight revisions made at the suggestion of the referee

R2 v1 2026-06-21T10:47:17.040Z