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arXiv · 1409.8207

Pizzetti formulae for Stiefel manifolds and applications

Kevin Coulembier·Mario Kieburg
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Abstract

Pizzetti's formula explicitly shows the equivalence of the rotation invariant integration over a sphere and the action of rotation invariant differential operators. We generalize this idea to the integrals over real, complex, and quaternion Stiefel manifolds in a unifying way. In particular we propose a new way to calculate group integrals and try to uncover some algebraic structures which manifest themselves for some well-known cases like the Harish-Chandra integral. We apply a particular case of our formula to an Itzykson-Zuber integral for the coset SO(4)/[SO(2)xSO(2)]. This integral naturally appears in the calculation of the two-point correlation function in the transition of the statistics of the Poisson ensemble and the Gaussian orthogonal ensemble in random matrix theory.

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Kevin Coulembier, Mario Kieburg. 2014-09-29. Pizzetti formulae for Stiefel manifolds and applications. https://doi.org/10.1007/s11005-015-0774-x

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