English

Moduli spaces of rational weighted stable curves and tropical geometry

Algebraic Geometry 2017-06-06 v3 Combinatorics

Abstract

We study moduli spaces of rational weighted stable tropical curves, and their connections with the classical Hassett spaces. Given a vector w of weights, the moduli space of tropical w-stable curves can be given the structure of a balanced fan if and only if w has only heavy and light entries. In this case, we can express the moduli space as the Bergman fan of a graphic matroid. Furthermore, we realize the tropical moduli space as a geometric tropicalization, and as a Berkovich skeleton, of the classical moduli space. This builds on previous work of Tevelev, Gibney--Maclagan, and Abramovich--Caporaso--Payne. Finally, we construct the moduli spaces of heavy/light weighted tropical curves as fiber products of unweighted spaces, and explore parallels with the algebraic world.

Keywords

Cite

@article{arxiv.1404.7426,
  title  = {Moduli spaces of rational weighted stable curves and tropical geometry},
  author = {Renzo Cavalieri and Simon Hampe and Hannah Markwig and Dhruv Ranganathan},
  journal= {arXiv preprint arXiv:1404.7426},
  year   = {2017}
}

Comments

26 pages, 8 TikZ figures. v3: Minor changes and corrections. Final version to appear in Forum of Mathematics, Sigma