General Capelli-type identities
Naihuan Jing, Yinlong Liu, Jian Zhang
TL;DR
The paper addresses the problem of unifying and extending Capelli-type identities for matrices with noncommutative entries by developing a deformation framework based on a matrix $H$ and immanants. It introduces a master Capelli identity that leverages Jucys–Murphy elements in the symmetric group algebra to relate products of $X$ and $Y$ to their immanant-type combinations, reducing to Williamson’s and Okounkov’s identities in appropriate limits. The authors then derive generalized Turnbull identities for determinants of symmetric matrices and permanents of antisymmetric matrices, as well as generalized Howe-Umeda-Kostant-Sahi identities for antisymmetric contexts, with Pfaffian techniques and a suite of lemmas underpinning the proofs. Collectively, these results furnish a cohesive, deformation-based framework that encompasses a breadth of classical identities, confirms conjectures on antisymmetric determinants, and broadens the toolkit for invariant-theoretic and representation-theoretic investigations within noncommutative algebra.
Abstract
The classical Capelli identity is an important determinantal identity of a matrix with noncommutative entries that determines the center of the enveloping algebra of the general linear Lie algebra, and was used by Weyl as a main tool to study irreducible representations in his famous book on classical groups. In 1996 Okounkov found higher Capelli identities involving immanants of the generating matrix of $U(gl(n))$ which correspond to arbitrary orthogonal idempotent of the symmetric group. It turns out that Williamson also discovered a general Capelli identity of immanants for $U(gl(n))$ in 1981. In this paper, we use a new method to derive a family of even more general Capelli identities that include the aforementioned Capelli identities as special cases as well as many other Capelli-type identities as corollaries. In particular, we obtain generalized Turnbull's identities for both symmetric and antisymmetric matrices, as well as the generalized Howe-Umeda-Kostant-Sahi identities for antisymmetric matrices which confirm the conjecture of Caracciolo, Sokal, and Sportiello.
