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arXiv · 1507.02248

Gaussian trivial ring extensions and fqp-rings

Francois Couchot
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Abstract

Let A be a commutative ring and E a non-zero A-module. Necessary and sufficient conditions are given for the trivial ring extension R of A by E to be either arithmetical or Gaussian. The possibility for R to be B{\'e}zout is also studied, but a response is only given in the case where pSpec A (a quotient space of Spec} A) is totally disconnected. Trivial ring extensions which are fqp-rings are characterized only in the local case. To get a general result we intoduce the class of fqf-rings satisfying a weaker property than fqp-ring. Moreover, it is proven that the finitistic weak dimension of a fqf-ring is 0, 1 or 2 and its global weak dimension is 0, 1 or infinite.

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Francois Couchot. 2015-07-08. Gaussian trivial ring extensions and fqp-rings. https://arxiv.org/abs/1507.02248

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