Article

Are complete intersections complete intersections?

Journal of Algebra (Impact Factor: 0.6). 09/2011; 371. DOI: 10.1016/j.jalgebra.2012.08.006
Source: arXiv

ABSTRACT A commutative local ring is generally defined to be a complete intersection
if its completion is isomorphic to the quotient of a regular local ring by an
ideal generated by a regular sequence. It has not previously been determined
whether or not such a ring is necessarily itself the quotient of a regular ring
by an ideal generated by a regular sequence. In this article, it is shown that
if a complete intersection is a one dimensional integral domain, then it is
such a quotient. However, an example is produced of a three dimensional
complete intersection domain which is not a homomorphic image of a regular
local ring, and so the property does not hold in general.

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Available from: David A. Jorgensen, Jul 21, 2014
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