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The Noether Bound in Invariant Theory of Finite Groups

โœ Scribed by Peter Fleischmann


Publisher
Elsevier Science
Year
2000
Tongue
English
Weight
133 KB
Volume
156
Category
Article
ISSN
0001-8708

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โœฆ Synopsis


Let R be a commutative ring, V a finitely generated free R-module and G GL R (V) a finite group acting naturally on the graded symmetric algebra A=Sym(V). Let ;(A G ) denote the minimal number m, such that the ring A G of invariants can be generated by finitely many elements of degree at most m. Furthermore, let H dG be a normal subgroup such that the index |G : H | is invertible in R. In this paper we prove the inequality

For H=1 and |G | invertible in R we obtain Noether's bound ;(A G ) |G|, which so far had been shown for arbitrary groups only under the assumption that the factorial of the group order, |G|!, is invertible in R.


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