• Choi, Eun-Mi (Department of mathematics Han Nam University) ;
  • Lee, Hei-Sook (Department of Mathematics Ewha Womans University)
  • Published : 2002.01.01


A Schur algebra was generalized to projective Schur algebra by admitting twisted group algebra. A Schur algebra is a projective Schur algebra with trivial 2-cocycle. In this paper we study situations that Schur algebra is a projective Schur algebra with nontrivial cocycle, and we find a criterion for a projective Schur algebra to be a Schur algebra.


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