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On Gorenstein fiber products and applications

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 نشر من قبل Saeed Nasseh
 تاريخ النشر 2017
  مجال البحث
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We show that a non-trivial fiber product $Stimes_k T$ of commutative noetherian local rings $S,T$ with a common residue field $k$ is Gorenstein if and only if it is a hypersurface of dimension 1. In this case, both $S$ and $T$ are regular rings of dimension 1. We also give some applications of this result.

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