Bull. Korean Math. Soc. 2005 Vol. 42, No. 3, 453-467 Printed September 1, 2005
Eunmi Choi Hannam University
Abstract : Let $K$ be an algebraic number field. If $k$ is the maximal cyclotomic subextension in $K$ then the Schur $K$-group $S(K)$ is obtained from the Schur $k$-group $S(k)$ by scalar extension. In the paper we study projective Schur group $PS(K)$ which is a generalization of Schur group, and prove that a projective Schur $K$-algebra is obtained by scalar extension of a projective Schur $k$-algebra where $k$ is the maximal radical extension in $K$ with mild condition.
Keywords : Schur algebra, projective Schur algebra, projective character