English

The refined solution to the Capelli eigenvalue problem for $\mathfrak{gl}(m|n)\oplus\mathfrak{gl}(m|n)$ and $\mathfrak{gl}(m|2n)$

Representation Theory 2024-05-27 v2 Combinatorics Rings and Algebras

Abstract

Let g\mathfrak g be either the Lie superalgebra gl(V)gl(V)\mathfrak{gl}(V)\oplus\mathfrak{gl}(V) where V:=CmnV:=\mathbb C^{m|n} or the Lie superalgebra gl(V)\mathfrak{gl}(V) where V:=Cm2nV:=\mathbb C^{m|2n}. Furthermore, let WW be the g\mathfrak g-module defined by W:=VVW:=V\otimes V^* in the former case and W:=S2(V)W:=\mathcal S^2(V) in the latter case. Associated to (g,W)(\mathfrak g,W) there exists a distinguished basis of Capelli operators {Dλ}λΩ\left\{D^\lambda\right\}_{\lambda\in\Omega}, naturally indexed by a set of hook partitions Ω\Omega, for the subalgebra of g\mathfrak g-invariants in the superalgebra PD(W)\mathcal{PD}(W) of superdifferential operators on WW. Let b\mathfrak b be a Borel subalgebra of g\mathfrak g. We compute eigenvalues of the DλD^\lambda on the irreducible g\mathfrak g-submodules of P(W)\mathcal{P}(W) and obtain them explicitly as the evaluation of the interpolation super Jack polynomials of Sergeev--Veselov at suitable affine functions of the b\mathfrak b-highest weight. While the former case is straightforward, the latter is significantly more complex. This generalizes a result by Sahi, Salmasian and Serganova for these cases, where such formulas were given for a fixed choice of Borel subalgebra.

Keywords

Cite

@article{arxiv.2307.02307,
  title  = {The refined solution to the Capelli eigenvalue problem for $\mathfrak{gl}(m|n)\oplus\mathfrak{gl}(m|n)$ and $\mathfrak{gl}(m|2n)$},
  author = {Mengyuan Cao and Monica Nevins and Hadi Salmasian},
  journal= {arXiv preprint arXiv:2307.02307},
  year   = {2024}
}