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Structure Theorems for Noncommutative Complete Local Rings


Fisher, James Louis (1969) Structure Theorems for Noncommutative Complete Local Rings. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/BMXA-R647.


If R is a ring with identity, let N(R) denote the Jacobson radical of R. R is local if R/N(R) is an artinian simple ring and ∩N(R)i = 0. It is known that if R is complete in the N(R)-adic topology then R is equal to (B)n, the full n by n matrix ring over B where E/N(E) is a division ring. The main results of the thesis deal with the structure of such rings B. In fact we have the following.

If B is a complete local algebra over F where B/N(B) is a finite dimensional normal extension of F and N(B) is finitely generated as a left ideal by k elements, then there exist automorphisms gi,...,gk of B/N(B) over F such that B is a homomorphic image of B/N[[x1,…,xk;g1,…,gk]] the power series ring over B/N(B) in noncommuting indeterminates xi, where xib = gi(b)xi for all b ϵ B/N.

Another theorem generalizes this result to complete local rings which have suitable commutative subrings. As a corollary of this we have the following. Let B be a complete local ring with B/N(B) a finite field. If N(B) is finitely generated as a left ideal by k elements then there exist automorphisms g1,…,gk of a v-ring V such that B is a homomorphic image of V [[x1,…,xk;g1,…,gk]].

In both these results it is essential to know the structure of N(B) as a two sided module over a suitable subring of B.

Item Type:Thesis (Dissertation (Ph.D.))
Subject Keywords:(Mathematics)
Degree Grantor:California Institute of Technology
Division:Physics, Mathematics and Astronomy
Major Option:Mathematics
Thesis Availability:Public (worldwide access)
Research Advisor(s):
  • Dean, Richard A.
Thesis Committee:
  • Unknown, Unknown
Defense Date:17 March 1969
Funding AgencyGrant Number
Ford FoundationUNSPECIFIED
Record Number:CaltechTHESIS:02222016-135018005
Persistent URL:
Default Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:9577
Deposited On:23 Feb 2016 15:52
Last Modified:26 Apr 2024 23:36

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