English

Fibrations on the 6-sphere and Clemens threefolds

Algebraic Geometry 2024-08-15 v2 Complex Variables Differential Geometry

Abstract

Let ZZ be a compact, connected 33-dimensional complex manifold with vanishing first and second Betti numbers and non-vanishing Euler characteristic. We prove that there is no holomorphic mapping from ZZ onto any 22-dimensional complex space. In other words, ZZ can only possibly fiber over a curve. This result applies in particular to a class of threefolds, known as Clemens threefolds, which are diffeomorphic to a connected sum k#(S3×S3)k \# (S^3 \times S^3) for k2k \geq 2. This result also gives a new restriction on any hypothetical complex structure on the 66-sphere S6S^6.

Keywords

Cite

@article{arxiv.2403.05035,
  title  = {Fibrations on the 6-sphere and Clemens threefolds},
  author = {Nobuhiro Honda and Jeff Viaclovsky},
  journal= {arXiv preprint arXiv:2403.05035},
  year   = {2024}
}

Comments

25 pages. Title has been updated, some proofs have been simplified, and some background material has been removed

R2 v1 2026-06-28T15:13:08.736Z