On the Schur indices of cuspidal unipotent characters
نویسنده
چکیده
In previous work of Gow, Ohmori, Lusztig and the author, the Schur indices of all unipotent characters of finite groups of Lie type have been explicitly determined except for six cases in groups of type F4, E7 and E8. In this paper, we show that the Schur indices of all cuspidal unipotent characters for type F4 and E8 are 1, assuming that the group is defined over a field of “good” characteristic. This settles four out of the six open cases. For type E7, we show that the Schur indices are at most 2. 2000 Mathematics Subject Classification: Primary 20C15; Secondary 20G40
منابع مشابه
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