English

Betti numbers of real semistable degenerations via real logarithmic geometry

Algebraic Geometry 2022-11-23 v1

Abstract

Let XCX\rightarrow C be a totally real semistable degeneration over a smooth real curve CC with degenerate fiber X0X_0. Assuming that the irreducible components of X0X_0 are simple from a cohomological point of view, we give a bound for the individual Betti numbers of a real smooth fiber near 00 in terms of the complex geometry of the degeneration. This generalizes previous work of Renaudineau-Shaw, obtained via combinatorial techniques, for tropical degenerations of hypersurfaces in smooth toric varieties. The main new ingredient is the use of real logarithmic geometry, which allows to work with not necessarily toric degenerations.

Keywords

Cite

@article{arxiv.2211.12134,
  title  = {Betti numbers of real semistable degenerations via real logarithmic geometry},
  author = {Emiliano Ambrosi and Matilde Manzaroli},
  journal= {arXiv preprint arXiv:2211.12134},
  year   = {2022}
}

Comments

23 pages, 1 figure, comments are welcome!