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Subrings of the first neighbourhood ring: II

Published online by Cambridge University Press:  24 October 2008

D. Kirby
Affiliation:
University of Southampton

Extract

In (1) and (2) we studied a lattice of extension rings associated with a commutative ring R with identity. When R, M is a one-dimensional Cohen-Macaulay local ring the elements of are just those integral extensions of R contained in the total quotient ring T(R) and such that lengthR(S/R) is finite. Experiments with local rings of singular points on algebraic curves indicate that only the simplest singularities give rise to finite lattices. So the problem arises as to which local rings R give rise to which finite lattices. In later papers this problem will be investigated in detail, at least when R is of low embedding dimension. The purpose of the present note is to establish some general results which indicate the size of the problem.

Type
Research Article
Copyright
Copyright © Cambridge Philosophical Society 1982

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References

REFERENCES

(1)Kirby, D.Subrings of the first neighbourhood ring. Math. Proc. Cambridge Phil. Soc. 86 (1979), 205214.CrossRefGoogle Scholar
(2)Kirby, D. and Adranghi, M. R.A lattice of extension rings for a commutative ring. Math. Proc. Cambridge Phil. Soc. 84 (1978), 225234.CrossRefGoogle Scholar
(3)Matlis, E.The multiplicity and reduction number of a one-dimensional local ring. Proc. London Math. Soc. 26 (1973), 273288.CrossRefGoogle Scholar
(4)Northcott, D. G.The neighbourhoods of a local ring. J. London Math. Soc. 30 (1955), 360375.CrossRefGoogle Scholar
(5)Northcott, D. G.A general theory of one-dimensional local rings. Proc. Glasgow Math. Soc. 2 (1956), 159169.CrossRefGoogle Scholar
(6)Northcott, D. G.Lessons on rings, modules and multiplicities (Cambridge University Press, 1968).CrossRefGoogle Scholar