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arXiv · 1703.05962

Hochschild cohomology of some quantum complete intersections

Karin Erdmann·Magnus Hellstrøm-Finnsen
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Abstract

We compute the Hochschild cohomology ring of the algebras $A= k\langle X, Y\rangle/ (X^a, XY-qYX, Y^a)$ over a field $k$ where $a\geq 2$ and where $q\in k$ is a primitive $a$-th root of unity. We find the the dimension of $\mathrm{HH}^n(A)$ and show that it is independent of $a$. We compute explicitly the ring structure of the even part of the Hochschild cohomology modulo homogeneous nilpotent elements.

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Karin Erdmann, Magnus Hellstrøm-Finnsen. 2017-03-17. Hochschild cohomology of some quantum complete intersections. https://doi.org/10.1142/s0219498818502158

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