Frontiers of Mathematics in China >
Commuting variety of Witt algebra
Received date: 15 May 2016
Accepted date: 27 Jul 2018
Published date: 29 Oct 2018
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Let g= W1 be the Witt algebra over an algebraically closed field k of characteristic p >3, and let = {(x, y) ∈g ×g | [x, y] = 0}be the commuting variety of g. In contrast with the case of classical Lie algebras of P. Levy [J. Algebra, 2002, 250: 473–484], we show that the variety is reducible, and not equidimensional. Irreducible components of and their dimensions are precisely given. As a consequence, the variety is not normal.
Key words: Witt algebra; irreducible component; dimension; commuting variety
Yu-Feng YAO , Hao CHANG . Commuting variety of Witt algebra[J]. Frontiers of Mathematics in China, 2018 , 13(5) : 1179 -1187 . DOI: 10.1007/s11464-018-0725-9
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