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arXiv · 1710.10029

Ideals in the enveloping algebra of the positive Witt algebra

Alexey V. Petukhov·Susan J. Sierra
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Abstract

Let $W_+$ be the positive Witt algebra, which has a $C$-basis $\{e_n: n \in Z_{\geq 1}\}$, with Lie bracket $[ e_i, e_j] = (j-i) e_{i+j}$. We study the two-sided ideal structure of the universal enveloping algebra $U(W_+)$ of $W_+$. We show that if $I$ is a (two-sided) ideal of $U(W_+)$ generated by quadratic expressions in the $e_i$, then $U(W_+)/I$ has finite Gelfand-Kirillov dimension, and that such ideals satisfy the ascending chain condition. We conjecture that analogous facts hold for arbitrary ideals of $U(W_+)$, and verify a version of these conjectures for radical Poisson ideals of the symmetric algebra $S(W_+)$.

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Alexey V. Petukhov, Susan J. Sierra. 2017-10-27. Ideals in the enveloping algebra of the positive Witt algebra. https://arxiv.org/abs/1710.10029

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