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arXiv · 1910.10204

Symmetrisation and the Feigin-Frenkel centre

Abstract

For simple Lie algebras of types B, C, and D, we provide new explicit formulas for the generators of the Feigin-Frenkel centre. These formulas make use of the symmetrisation map as well as some well-chosen symmetric invariants of $\mathfrak g$. There are some general results on the role of the symmetrisation map in the explicit description of the FF-centre. The advantage of our method is that it reduces questions about elements of the FF-centre to questions on the structure of the symmetric invariants in a type-free way. As an illustration, we deal with type G$_2$ by hand.

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BibTeXRIS

Oksana Yakimova. 2020-05-06. Symmetrisation and the Feigin-Frenkel centre. https://arxiv.org/abs/1910.10204

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