English

Worldsheet Instantons and Torsion Curves

High Energy Physics - Theory 2008-01-29 v1

Abstract

We study aspects of worldsheet instantons relevant to a heterotic standard model. The non-simply connected Calabi-Yau threefold used admits Z_3 x Z_3 Wilson lines, and a more detailed investigation shows that the homology classes of curves are H_2(X,Z)=Z^3+Z_3+Z_3. We compute the genus-0 prepotential, this is the first explicit calculation of the Gromov-Witten invariants of homology classes with torsion (finite subgroups). In particular, some curve classes contain only a single instanton. This ensures that the Beasley-Witten cancellation of instanton contributions cannot happen on this (non-toric) Calabi-Yau threefold.

Cite

@article{arxiv.0801.4154,
  title  = {Worldsheet Instantons and Torsion Curves},
  author = {Volker Braun and Maximilian Kreuzer and Burt A. Ovrut and Emanuel Scheidegger},
  journal= {arXiv preprint arXiv:0801.4154},
  year   = {2008}
}

Comments

9 pages. To appear in the proceedings of the first Sowers Theoretical Physics workshop, Virginia Tech, May 2007

R2 v1 2026-06-21T10:06:53.700Z