Abstract
It is elementary that a principal prime ideal in a Noetherian ring can have codimension at most 1. A sharper statement is this: Any prime properly contained in a proper principal ideal has codimension 0. Proof: If on the contrary, Q ⫋ P ⫋ (x) in a ring R, with P and Q prime, then factoring out Q we can assume that Q = 0, and thus that R is a domain. If y ∈ P, then y = ax for some a, and since x ∉ P it follows that a ∈ P; thus P = xP. By Corollary 4.7, (1 - b)P = 0 for some b ∈ (x). Since R is a domain, we must have b = 1, so (x) is not proper, a contradiction.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
Author information
Authors and Affiliations
Rights and permissions
Copyright information
© 1995 Springer-Verlag New York, Inc.
About this chapter
Cite this chapter
Eisenbud, D. (1995). The Principal Ideal Theorem and Systems of Parameters. In: Commutative Algebra. Graduate Texts in Mathematics, vol 150. Springer, New York, NY. https://doi.org/10.1007/978-1-4612-5350-1_12
Download citation
DOI: https://doi.org/10.1007/978-1-4612-5350-1_12
Publisher Name: Springer, New York, NY
Print ISBN: 978-3-540-78122-6
Online ISBN: 978-1-4612-5350-1
eBook Packages: Springer Book Archive