English

Diptych varieties. II: Polar varieties

Algebraic Geometry 2015-07-22 v3

Abstract

Part I introduced diptych varieties VABLMV_{ABLM} and gave a rigorous construction of them in the case d,e2d,e\ge 2 and de>4de>4. Here we prove the existence of VABLMV_{ABLM} in all the cases with de4de\le4. At the same time we construct some classes of interesting quasihomogeneous spaces for groups such as \GL(2)×\Gmr\GL(2)\times\G_m^r based on the algebra of polars.

Keywords

Cite

@article{arxiv.1208.5858,
  title  = {Diptych varieties. II: Polar varieties},
  author = {Gavin Brown and Miles Reid},
  journal= {arXiv preprint arXiv:1208.5858},
  year   = {2015}
}

Comments

24 pages. A tribute to Yujiro Kawamata, to appear in his sixtieth birthday conference proceedings, ASPM 2015. The webpage at http://homepages.warwick.ac.uk/staff/G.Brown/diptych.html contains links to auxiliary material. (First update adds more detail to calculations of polars and includes a new key variety to handle small cases all together. Only minor editing revisions in later update.)