## Orthogonal representations of twisted forms of $\operatorname {SL}_2$

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- by Skip Garibaldi
- Represent. Theory
**12**(2008), 435-446 - DOI: https://doi.org/10.1090/S1088-4165-08-00335-X
- Published electronically: December 8, 2008
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## Abstract:

For every absolutely irreducible orthogonal representation of a twisted form of $\operatorname {SL}_2$ over a field of characteristic zero, we compute the âuniqueâ symmetric bilinear form that is invariant under the group action. We also prove the analogous result for Weyl modules in prime characteristic (including characteristic 2) and an isomorphism between two symmetric bilinear forms given by binomial coefficients.## References

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## Bibliographic Information

**Skip Garibaldi**- Affiliation: Department of Mathematics and Computer Science, Emory University, Atlanta, Georgia 30322
- MR Author ID: 622970
- ORCID: 0000-0001-8924-5933
- Email: skip@member.ams.org
- Received by editor(s): November 6, 2007
- Received by editor(s) in revised form: August 4, 2008
- Published electronically: December 8, 2008
- © Copyright 2008
American Mathematical Society

The copyright for this article reverts to public domain 28 years after publication. - Journal: Represent. Theory
**12**(2008), 435-446 - MSC (2000): Primary 20G05; Secondary 11E04, 11E76, 20G15
- DOI: https://doi.org/10.1090/S1088-4165-08-00335-X
- MathSciNet review: 2465801