## Finite-dimensional representations of minimal nilpotent W-algebras and zigzag algebras

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- by Alexey Petukhov PDF
- Represent. Theory
**22**(2018), 223-245 Request permission

## Abstract:

Let $\frak g$ be a simple finite-dimensional Lie algebra over an algebraically closed field $\mathbb F$ of characteristic 0. We denote by $\mathrm {U}(\frak g)$ the universal enveloping algebra of $\frak g$. To any nilpotent element $e\in \frak g$ one can attach an associative (and noncommutative as a general rule) algebra $\mathrm {U}(\frak g, e)$ which is in a proper sense a “tensor factor” of $\mathrm {U}(\frak g)$. In this article we consider the case in which $e$ belongs to the minimal nonzero nilpotent orbit of $\frak g$. Under these assumptions $\mathrm {U}(\frak g, e)$ was described explicitly in terms of generators and relations. One can expect that the representation theory of $\mathrm {U}(\frak g, e)$ would be very similar to the representation theory of $\mathrm {U}(\frak g)$. For example one can guess that the category of finite-dimensional $\mathrm {U}(\frak g, e)$-modules is semisimple.

The goal of this article is to show that this is the case if $\frak g$ is not simply-laced. We also show that, if $\frak g$ is simply-laced and is not of type $A_n$, then the regular block of finite-dimensional $\operatorname {U}(\frak g, e)$-modules is equivalent to the category of finite-dimensional modules of a zigzag algebra.

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## Additional Information

**Alexey Petukhov**- Affiliation: The University of Manchester, Oxford Road M13 9PL, Manchester, United Kingdom; and Institute for Information Transmission Problems, Bolshoy Karetniy 19-1, Moscow 127994, Russia
- MR Author ID: 828039
- Email: alex-{}-2@yandex.ru
- Received by editor(s): June 3, 2017
- Received by editor(s) in revised form: July 3, 2018
- Published electronically: November 13, 2018
- Additional Notes: The main result of the research presented in Sections 7, 8 was carried out at the IITP at the expense of Russian Science Foundation (project No. 14-50-00150). Other sections of this work were carried out as a part of a project on W-algebras supported by Leverhulme Trust Grant RPG-2013-293.
- © Copyright 2018 American Mathematical Society
- Journal: Represent. Theory
**22**(2018), 223-245 - MSC (2010): Primary 22E47, 16D50, 16D90
- DOI: https://doi.org/10.1090/ert/516
- MathSciNet review: 3875450