## $\mathbb {Z}$-graded simple rings

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- by J. Bell and D. Rogalski PDF
- Trans. Amer. Math. Soc.
**368**(2016), 4461-4496 Request permission

## Abstract:

The Weyl algebra over a field $k$ of characteristic $0$ is a simple ring of Gelfand-Kirillov dimension 2, which has a grading by the group of integers. We classify all $\mathbb {Z}$-graded simple rings of GK-dimension 2 and show that they are graded Morita equivalent to generalized Weyl algebras as defined by Bavula. More generally, we study $\mathbb {Z}$-graded simple rings $A$ of any dimension which have a graded quotient ring of the form $K[t, t^{-1}; \sigma ]$ for a field $K$. Under some further hypotheses, we classify all such $A$ in terms of a new construction of simple rings which we introduce in this paper. In the important special case that $\operatorname {GKdim} A = \operatorname {tr.deg}(K/k) + 1$, we show that $K$ and $\sigma$ must be of a very special form. The new simple rings we define should warrant further study from the perspective of noncommutative geometry.## References

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## Additional Information

**J. Bell**- Affiliation: Department of Pure Mathematics, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1
- MR Author ID: 632303
- Email: jpbell@uwaterloo.ca
**D. Rogalski**- Affiliation: Department of Mathematics, University of California, San Diego, 9500 Gilman Drive #0112, La Jolla, California 92093-0112
- MR Author ID: 734142
- Email: drogalsk@math.ucsd.edu
- Received by editor(s): October 29, 2013
- Received by editor(s) in revised form: May 3, 2014
- Published electronically: October 14, 2015
- Additional Notes: The first author was partially supported by NSERC grant 31-611456.

The second author was partially supported by NSF grants DMS-0900981 and DMS-1201572. - © Copyright 2015 American Mathematical Society
- Journal: Trans. Amer. Math. Soc.
**368**(2016), 4461-4496 - MSC (2010): Primary 16D30, 16P90, 16S38, 16W50
- DOI: https://doi.org/10.1090/tran/6472
- MathSciNet review: 3453377