DEGREES OF IRREDUCIBLE PROJECTIVE REPRESENTATIONS OF FINITE GROUPSf
نویسنده
چکیده
where St and S2 are projective representations of G. An irreducible projective representation is one that is not reducible. In this paper, we study the degrees of irreducible projective representations of a finite group G over an algebraically closed field K. In Theorem 2, we require further that char KJ(\G\. The degree of an irreducible projective representation of a finite group G, over the complex field, was first studied by Schur [5]. He proved that the degree of such a projective representation of G divides \G\. The proof depends on his method of representation groups, and the following well-known theorem (also due to him): The degree of an irreducible complex character of a finite group R divides (R : Z(/?)), the index of Z(R) in the group R. We now assume that K is an algebraically closed field such that charK )(\G\.
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