R-charge Conservation and More in Factorizable and Non-Factorizable Orbifolds
Abstract
We consider the string theory origin of R-charge conservation laws in heterotic orbifold compactifications, deriving the corresponding string coupling selection rule for factorizable and non-factorizable orbifolds, with prime ordered and non-prime ordered point groups. R-charge conservation arises due to symmetries among the worldsheet instantons that can mediate the couplings. Among our results is a previously missed non-trivial contribution to the conserved R-charges from the Gamma-phases in non-prime orbifolds, which weakens the R-charge selection rule. Symmetries among the worldsheet instantons can also lead to additional selection rules for some couplings. We make a similar analysis for Rule 4 or the 'torus lattice selection rule'. Moreover, we identify a new string selection rule, that we call Rule 6 or the 'coset vector selection rule'.
Cite
@article{arxiv.1301.2322,
title = {R-charge Conservation and More in Factorizable and Non-Factorizable Orbifolds},
author = {Nana Geraldine Cabo Bizet and Tatsuo Kobayashi and Damian Kaloni Mayorga Pena and Susha L. Parameswaran and Matthias Schmitz and Ivonne Zavala},
journal= {arXiv preprint arXiv:1301.2322},
year = {2013}
}
Comments
35 pages, 2 figures, v2: minor corrections, new references added, matches version to appear in JHEP