flat module
FlatModule
2002-01-05 16:06:05
2003-09-14 14:58:31
Definition
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A right module $M$ over a ring $R$ is {\it flat}
if the tensor product functor $M \otimes_R (-)$
is an exact functor.
Similarly, a left module $N$ over $R$ is {\it flat}
if the tensor product functor $(-) \otimes_R N$
is an exact functor.