Then there is an algebra B and a simple injective B-module S' with proj.dim. S' ≥ 1,
such that the full subcategory Y of the B-modules whithout
a direct summand S'
is equivalent to G.
If A is given by a quiver with relations,
then S corresponds to a sink s with no relation ending in it. B is obtained by just reversing all the arrows ending in s ("reflection"). |
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The corresponding module categories: |
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