Abstract
D. Prasad showed that the sign of a self-dual representation of a finite or p-adic reductive group is often detected by a central element. We study the extension of his results to some more general situations and make some observations about the consequences of his results.
Acknowledgment
The author thanks Alan Roche for pointing out mistakes in an earlier draft of this article. The statements of Corollaries 2 and 9 are due to him. They were remarked to the author during our correspondence. The author also thanks Dipendra Prasad for many helpful discussions. Section 3.3 in this note benefits from the ideas in [Citation2]. The author is most thankful to the anonymous referee for his thorough report. The contents of §3.2 are entirely due to him.