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Superconducting strings in $E_{6}$

¹Cosmology, Gravity and Astroparticle Physics Group, Center for Theoretical Physics of the Universe, Institute for Basic Science, Daejeon 34126, Republic of Korea
²Bartol Research Institute, Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA

Phys. Rev. D 112, L101903 – Published 13 November, 2025

DOI: https://doi.org/10.1103/nym6-vpms

Abstract

We discuss the appearance of superconducting strings in $E_{6}$ grand unification, keeping track of the magnetic monopole flux that precedes the formation of the string flux tube. This flux matching ensures compatibility with the quantum tunneling of a monopole-antimonopole pair on a metastable string. We identify two realistic $E_{6}$ models with superconducting (metastable) strings that also carry zero modes of the right-handed Majorana neutrinos and dark matter particles. Depending on the symmetry breaking scale associated with the strings, the latter could be a source of observable gravitational waves, intermediate scale dark matter, and the observed baryon asymmetry via leptogenesis. Topologically stable superconducting strings also appear if the $E_{6}$ symmetry breaking leaves unbroken the $Z_{2}$ subgroup of $Z_{4}$ , the center of SO(10). The zero modes of the Standard Model fermions are the charge carriers in this case. Finally, the flux matching condition ensures that the Aharonov-Bohm phase change in going around the metastable strings is an integer multiple of $2 π$ for all fields. The fields in the spinorial representation of SO(10) acquire a phase change of $\exp (\pm i π)$ if taken around the topologically stable $Z_{2}$ string.

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References (40)

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Phys. Rev. D 112, L101903– Published 13 November, 2025

Vol. 112, Iss. 10 — 15 November 2025

Received 23 September 2025
Accepted 19 October 2025

DOI: https://doi.org/10.1103/nym6-vpms

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP³.

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Superconducting strings in $E_{6}$

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Superconducting strings in E6

Abstract

Physics Subject Headings (PhySH)

Article Text

References (40)

Superconducting strings in $E_{6}$