English

Quotients by non-reductive algebraic group actions

Algebraic Geometry 2008-12-15 v4

Abstract

Given a suitable action on a complex projective variety X of a non-reductive affine algebraic group H, this paper considers how to choose a reductive group G containing H and a projective completion of G x_H X which is a reductive envelope in the sense of math.AG/0703131. In particular it studies the family of examples given by moduli spaces of hypersurfaces in the weighted projective plane P(1,1,2) obtained as quotients by linear actions of the (non-reductive) automorphism group of P(1,1,2).

Keywords

Cite

@article{arxiv.0801.4607,
  title  = {Quotients by non-reductive algebraic group actions},
  author = {Frances Kirwan},
  journal= {arXiv preprint arXiv:0801.4607},
  year   = {2008}
}

Comments

Minor corrections made on pages 12 and 20; references updated. To appear in 'Moduli Spaces and Vector Bundles' (CUP) in honour of Peter Newstead

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