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arXiv · 1204.3218

Rigidity of quantum tori and the Andruskiewitsch-Dumas conjecture

Milen Yakimov
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Abstract

We prove the Andruskiewitsch-Dumas conjecture that the automorphism group of the positive part of the quantized universal enveloping algebra $U_q({\mathfrak{g}})$ of an arbitrary finite dimensional simple Lie algebra g is isomorphic to the semidirect product of the automorphism group of the Dynkin diagram of g and a torus of rank equal to the rank of g. The key step in our proof is a rigidity theorem for quantum tori. It has a broad range of applications. It allows one to control the (full) automorphism groups of large classes of associative algebras, for instance quantum cluster algebras.

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Milen Yakimov. 2012-04-14. Rigidity of quantum tori and the Andruskiewitsch-Dumas conjecture. https://arxiv.org/abs/1204.3218

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