Hostname: page-component-586b7cd67f-g8jcs Total loading time: 0 Render date: 2024-11-27T19:53:40.717Z Has data issue: false hasContentIssue false

Primitive Ore extensions

Published online by Cambridge University Press:  18 May 2009

D. A. Jordan
Affiliation:
Department of Pure Mathematics, University of Sheffield, Sheffield S10 2TN
Rights & Permissions [Opens in a new window]

Extract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Apart from simple Ore extensions such as the Weyl algebras, the best known example of a primitive Ore extension is the universal enveloping algebra U(g) of the 2-dimensional solvable Lie algebra g over a field k of characteristic zero, see [4, p. 22]. U(g) is a polynomial algebra over k in two indeterminates x and y with multiplication subject to the relation xyyx = y, and may be regarded either as an Ore extension of k [x] by the k-automorphism which maps x to x – 1 or as an Ore extension of k[y] by the derivation yd/dy. The argument suggested in [4, p. 22] to prove the primitivity of U(g) can easily be generalised [6] to show that, if α is an automorphism of the ring R then the following conditions are sufficient for R[x, α] to be primitive: (i) no power αs, s ≧ 1, of α is inner; (ii) the only ideals of R invariant under α are 0 and R. These conditions are necessary and sufficient for the simplicity of the skew Laurent polynomial ring R[x, x–1, α] but are not necessary for the primitivity of R[x, α] (the ordinary polynomial ring D[x] over a division ring D not algebraic over its centre is easily seen to be primitive).

Type
Research Article
Copyright
Copyright © Glasgow Mathematical Journal Trust 1977

References

REFERENCES

1.Borho, W., Gabriel, P. and Rentschler, R., Primideale in EinhuUenden auflösbarer Lie Algebren, Lecture Notes in Mathematics No. 357 (Springer-Verlag, 1973).CrossRefGoogle Scholar
2.Eisenbud, D. and Robson, J. C., Modules over Dedekind prime rings, J. Algebra 16 (1970), 6785.CrossRefGoogle Scholar
3.Faith, C., Algebra: Rings, modules and categories I (Springer-Verlag, 1973).CrossRefGoogle Scholar
4.Jacobson, N., Structure of rings (Amer. Math. Soc. Colloquium Publications, rev. edition, 1964).Google Scholar
5.Jordan, D. A., Noetherian Ore extensions and Jacobson rings, J. London Math. Soc. (2), 10 (1975), 281291.CrossRefGoogle Scholar
6.Jordan, D. A., Ph.D. thesis, University of Leeds (1975).Google Scholar