Mathematische Zeitschrift

, Volume 244, Issue 1, pp 163-174

First online:

Invariant rings and quasiaffine quotients

  • J. WinkelmannAffiliated withKorea Institute for Advanced Study - KIAS, School of Mathematics, 207-43 Cheongryangri-dong, Dongdaemun-gu, Seoul 130-012, Republic Korea

Rent the article at a discount

Rent now

* Final gross prices may vary according to local VAT.

Get Access


We study Hilbert's fourteenth problem from a geometric point of view. Nagata's celebrated counterexample demonstrates that for an arbitrary group action on a variety the ring of invariant functions need not be isomorphic to the ring of functions of an affine variety. In this paper we will show that nevertheless it is always isomorphic to the ring of functions on a quasi-affine variety.

Mathematics Subject Classification (2000): 13A50, 14R20, 14L30