Nonvanishing superpotentials in heterotic string theory and discrete torsion
Here, we study the nonperturbative superpotential in E8 E8 heterotic string theory on a nonsimply connected CalabiYau manifold X, as well as on its simply connected covering space ~X . The superpotential is induced by the string wrapping holomorphic, isolated, genus 0 curves. According to the residue theorem of Beasley and Witten, the nonperturbative superpotential must vanish in a large class of heterotic vacua because the contributions from curves in the same homology class cancel each other. We point out, however, that in certain cases the curves treated in the residue theorem as lying in the same homology class, can actually have different area with respect to the physical Kahler form and can be in different homology classes. In these cases, the residue theorem is not directly applicable and the structure of the superpotential is more subtle. We also show, in a specific example, that the superpotential is nonzero both on ~X and on X. On the nonsimply connected manifold X, we explicitly compute the leading contribution to the superpotential from all holomorphic, isolated, genus 0 curves with minimal area. Furthermore, the reason for the nonvanishing of the superpotental on X is that the second homology class contains a finitemore »
 Authors:

^{[1]};
^{[2]}
 Univ. of Western Australia, Crawley, WA (Australia). School of Physics
 Univ. of Pennsylvania, Philadelphia, PA (United States). Dept. of Physics and Astronomy
 Publication Date:
 Grant/Contract Number:
 SC0007901
 Type:
 Accepted Manuscript
 Journal Name:
 Journal of High Energy Physics (Online)
 Additional Journal Information:
 Journal Name: Journal of High Energy Physics (Online); Journal Volume: 2017; Journal Issue: 1; Journal ID: ISSN 10298479
 Publisher:
 Springer Berlin
 Research Org:
 Univ. of Pennsylvania, Philadelphia, PA (United States)
 Sponsoring Org:
 USDOE
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; Superstring Vacua; Superstrings and Heterotic Strings
 OSTI Identifier:
 1360741
Buchbinder, Evgeny I., and Ovrut, Burt A.. Nonvanishing superpotentials in heterotic string theory and discrete torsion. United States: N. p.,
Web. doi:10.1007/JHEP01(2017)038.
Buchbinder, Evgeny I., & Ovrut, Burt A.. Nonvanishing superpotentials in heterotic string theory and discrete torsion. United States. doi:10.1007/JHEP01(2017)038.
Buchbinder, Evgeny I., and Ovrut, Burt A.. 2017.
"Nonvanishing superpotentials in heterotic string theory and discrete torsion". United States.
doi:10.1007/JHEP01(2017)038. https://www.osti.gov/servlets/purl/1360741.
@article{osti_1360741,
title = {Nonvanishing superpotentials in heterotic string theory and discrete torsion},
author = {Buchbinder, Evgeny I. and Ovrut, Burt A.},
abstractNote = {Here, we study the nonperturbative superpotential in E8 E8 heterotic string theory on a nonsimply connected CalabiYau manifold X, as well as on its simply connected covering space ~X . The superpotential is induced by the string wrapping holomorphic, isolated, genus 0 curves. According to the residue theorem of Beasley and Witten, the nonperturbative superpotential must vanish in a large class of heterotic vacua because the contributions from curves in the same homology class cancel each other. We point out, however, that in certain cases the curves treated in the residue theorem as lying in the same homology class, can actually have different area with respect to the physical Kahler form and can be in different homology classes. In these cases, the residue theorem is not directly applicable and the structure of the superpotential is more subtle. We also show, in a specific example, that the superpotential is nonzero both on ~X and on X. On the nonsimply connected manifold X, we explicitly compute the leading contribution to the superpotential from all holomorphic, isolated, genus 0 curves with minimal area. Furthermore, the reason for the nonvanishing of the superpotental on X is that the second homology class contains a finite part called discrete torsion. As a result, the curves with the same area are distributed among different torsion classes and, hence, do not cancel each other},
doi = {10.1007/JHEP01(2017)038},
journal = {Journal of High Energy Physics (Online)},
number = 1,
volume = 2017,
place = {United States},
year = {2017},
month = {1}
}