Separation of variables in the semistable range

Roman Lavicka

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arXiv · 1902.02555

Separation of variables in the semistable range

Roman Lavicka

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Abstract

In this paper, we give an alternative proof of separation of variables for scalar-valued polynomials $P:(\mathbb R^m)^k\to\mathbb C$ in the semistable range $m\geq 2k-1$ for the symmetry given by the orthogonal group $O(m)$. It turns out that uniqueness of the decomposition of polynomials into spherical harmonics is equivalent to irreducibility of generalized Verma modules for the Howe dual partner $sp(2k)$ generated by spherical harmonics. We believe that this approach might be applied to the case of spinor-valued polynomials and to other settings as well.

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Roman Lavicka. 2019-02-07. Separation of variables in the semistable range. https://arxiv.org/abs/1902.02555

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