3
$\begingroup$

I am wondering if the following rings are catenary:

  1. If $k$ is a field, is the ring of formal power series $k[[X_1,\dots,X_n]]$ catenary?
  2. Is the ring of complex power series with a non-zero radius of convergence $\Bbb C\{X_1,\dots,X_n\}$ (id est the ring of germs of holomorphic functions at zero) a catenary ring?
$\endgroup$
1
  • 3
    $\begingroup$ Until a few minutes ago, the comments contained a link to the wikipedia article catenary ring. As that article makes clear, the catenary condition should be viewed as the weakest in a hierarchy of "smoothness" conditions on a ring, the strongest of which is the property of being a regular ring. In his answer, Leo Alonso observes that these rings are in fact regular. So basically, the question asks "are these rings nice in a weak sense", and the answer is "yes, and don't worry -- they're actually nice in the strongest possible sense"! $\endgroup$
    – Tim Campion
    Apr 2, 2019 at 19:34

1 Answer 1

10
$\begingroup$

Yes, they are regular (the maximal ideal is generated by a number of elements equal to its dimension) and therefore Cohen-Macaulay (Matsumura, Theorem 17.8). And a Cohen Macaulay ring is catenary (Matsumura, Theorem 17.4).

Matsumura, Commutative Ring Theory, CUP, 1986

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.