English

Combinatorics of the irreducible components of $\mathcal{H}_n^{\Gamma}$ in type $D$ and $E$

Combinatorics 2025-05-29 v3 Representation Theory

Abstract

In this article, we give a combinatorial model in terms of symmetric cores of the indexing set of the irreducible components of HnΓ\mathcal{H}_n^{\Gamma} (the Γ\Gamma-fixed points of the Hilbert scheme of nn points in C2\mathbb{C}^2) containing a monomial ideal, whenever Γ\Gamma is a finite subgroup of SL2(C)\mathrm{SL}_2(\mathbb{C}) isomorphic to the binary dihedral group. Moreover, we show that if Γ\Gamma is a subgroup of SL2(C)\mathrm{SL}_2(\mathbb{C}) isomorphic to the binary tetrahedral group, to the binary octahedral group or to the binary icosahedral group, then the Γ\Gamma-fixed points of Hn\mathcal{H}_n which are also fixed under T1\mathbb{T}_1, the maximal diagonal torus of SL2(C)\mathrm{SL}_2(\mathbb{C}), are in fact SL2(C)\mathrm{SL}_2(\mathbb{C})-fixed points. Finally, we prove that in that case, the irreducible components of HnΓ\mathcal{H}_n^{\Gamma} containing a T1\mathbb{T}_1-fixed point are of dimension 00.

Keywords

Cite

@article{arxiv.2408.08251,
  title  = {Combinatorics of the irreducible components of $\mathcal{H}_n^{\Gamma}$ in type $D$ and $E$},
  author = {Raphaël Paegelow},
  journal= {arXiv preprint arXiv:2408.08251},
  year   = {2025}
}