English

Rationally connected varieties and fundamental groups

Algebraic Geometry 2007-05-23 v2

Abstract

Let U be an open subset of a unirational variety (or more generally of a separably rationally connected variety). We prove that there is rational curve C in U such that the fundamental group of C surjects onto the fundamental group of U. The proof improves the earlier proof (math.AG/0003138) and works in any characteristic. Much improved version, thanks to comments of Colliot-Th\'el\`ene.

Keywords

Cite

@article{arxiv.math/0203174,
  title  = {Rationally connected varieties and fundamental groups},
  author = {János Kollár},
  journal= {arXiv preprint arXiv:math/0203174},
  year   = {2007}
}