This paper describes generic patterns for the extensions between simple modules of a finite Chevalley group. A one-to-one correspondence between these extensions and the extensions between certain simple modules of the ambient algebraic group are established. It is shown that an extension appears in
Rationality Problem for Generic Tori in Simple Groups
✍ Scribed by Anne Cortella; Boris Kunyavskiĭ
- Publisher
- Elsevier Science
- Year
- 2000
- Tongue
- English
- Weight
- 178 KB
- Volume
- 225
- Category
- Article
- ISSN
- 0021-8693
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✦ Synopsis
We prove that except for several already known cases, the generic torus of a simple (adjoint or simply connected) group is not stably rational. This confirms a conjecture by Le Bruyn on generic norm tori.
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