English

Deformation classification of real non-singular cubic threefolds with a marked line

Algebraic Geometry 2019-03-04 v2

Abstract

We prove that the space of pairs (X,l)(X,l) formed by a real non-singular cubic hypersurface XP4X\subset P^4 with a real line lXl\subset X has 18 connected components and give for them several quite explicit interpretations. The first one relates these components to the orbits of the monodromy action on the set of connected components of the Fano surface FR(X)F_\mathbb{R}(X) formed by real lines on XX. For another interpretation we associate with each of the 18 components a well defined real deformation class of real non-singular plane quintic curves and show that this deformation class together with the real deformation class of XX characterizes completely the component.

Keywords

Cite

@article{arxiv.1803.00535,
  title  = {Deformation classification of real non-singular cubic threefolds with a marked line},
  author = {Sergey Finashin and Viatcheslav Kharlamov},
  journal= {arXiv preprint arXiv:1803.00535},
  year   = {2019}
}

Comments

63 pages, 9 Figures, updated to the accepted version in Arnold Math Journal