Abstract
A well known theorem of Chouinard states that if G is a finite group and k is a field of characteristic p > 0, then a kG-module is projective precisely when its restrictions to all elementary abelian p-subgroups of G are projective. We investigate some similar situations in which the restrictions to subalgebras detect the projectivity of a module over an algebra.
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Carlson, J.F. (2006). When is projectivity detected on subalgebras?. In: Bosma, W., Cannon, J. (eds) Discovering Mathematics with Magma. Algorithms and Computation in Mathematics, vol 19. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-540-37634-7_9
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DOI: https://doi.org/10.1007/978-3-540-37634-7_9
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-540-37632-3
Online ISBN: 978-3-540-37634-7
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