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Summary:
STABLE COHOMOLOGY OVER LOCAL RINGS
LUCHEZAR L. AVRAMOV AND OANA VELICHE
Abstract.For a commutative noetherian ring R with residue field k stable
cohomology modules dExtnR(k, k) have been defined for each n 2 Z, but th*
*eir
meaning has remained elusive. It is proved that the k-rank of any dExtnR*
*(k, k)
characterizes important properties of R, such as being regular, complete*
* inter-
section, or Gorenstein. These numerical characterizations are based on r*
*esults
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