COTORSION DIMENSIONS OVER GROUP RINGS

author

  • A. Hajizamani Department of Mathematics, University of Hormozgan, P.O. Box 3995, Bandarabbas, Iran.
Abstract:

Let $Gamma$ be a group, $Gamma'$ a subgroup of $Gamma$ with finite index and $M$ be a $Gamma$-module. We show that $M$ is cotorsion if and only if it is cotorsion as a $Gamma'$-module. Using this result, we prove that the global cotorsion dimensions of rings $ZGamma$ and $ZGamma'$ are equal.

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Journal title

volume 7  issue 1

pages  25- 32

publication date 2019-09-01

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