Duality between injective envelopes and flat coversWe establish a duality between injective envelopes and flat covers over a
commutative Noetherian ring. One case of this duality states that a morphism is
an injective envelope, if and only if its Matlis dual is a flat cover. We also
show that if we swap injective envelopes and flat covers in this duality,
neither implication is true in general.
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