Thursday, 5 August 2010

ag.algebraic geometry - Is the field of invariants k(V)G purely transcendental over k?

Reference: http://www.math.u-psud.fr/~colliot/mumbai04.pdf



Proposition 4.3. on page 18 in the above reference reads as follows:
Assume k=overlinek. If V is a finite dimensional vector space over k and GsubsetGL(V) is an (abstract) abelian group consisting of semisimple elements, then k(V)G is pure.



I would like to find an abelian group GsubsetGL(V) such that k(V)G is not pure (if it exists it would need to be infinite due to Fischer's theorem, and not a connected solvable group according to Proposition 4.4).



Thanks.

No comments:

Post a Comment