System of parameters

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In mathematics, a system of parameters for a local Noetherian ring of Krull dimension d with maximal ideal m is a set of elements x1, ..., xd that satisfies any of the following equivalent conditions:

  1. m is a minimal prime over (x1, ..., xd).
  2. The radical of (x1, ..., xd) is m.
  3. Some power of m is contained in (x1, ..., xd).
  4. (x1, ..., xd) is m-primary.

Every local Noetherian ring admits a system of parameters. [1]

It is not possible for fewer than d elements to generate an ideal whose radical is m because then the dimension of R would be less than d.

If M is a k-dimensional module over a local ring, then x1, ..., xk is a system of parameters for M if the length of M / (x1, ..., xk).

General references

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References

  1. "Math 711: Lecture of September 5, 2007" (PDF). University of Michigan. September 5, 2007. Retrieved May 31, 2022.