Non-supersymmetric heterotic strings on a circle

• Published in: The journal of high energy physics 2024-12, Vol.2024 (12), p.82-59, Article 82
• Main Authors: Fraiman, Bernardo, Graña, Mariana, Parra De Freitas, Héctor, Sethi, Savdeep
• Format: Article
• Language: English
• Subjects: Classical and Quantum Gravitation; Cosmological constant; Elementary Particles; Lattice vibration; Loci; Physics; Physics and Astronomy; Potential energy; Quantum Field Theories; Quantum Field Theory; Quantum Physics; Regular Article - Theoretical Physics; Relativity Theory; Saddle points; String Theory; Strings; Superstring Vacua; Superstrings and Heterotic Strings; Supersymmetry; Symmetry; Tachyons; Toruses
• ISSN: 1029-8479; 1029-8479
• DOI: 10.1007/JHEP12(2024)082

A bstract Motivated by a recent construction of non-supersymmetric AdS 3 , we revisit the O (16) × O (16) heterotic string compactified on a torus. The string one-loop potential energy has interesting dependence on the classical moduli; extrema of this potential include loci where the gauge symmetry is maximally enhanced. Focusing on the case of a circle, we use lattice embeddings to find the maximal enhancement points together with their spectra of massless and tachyonic modes. We find an extended Dynkin diagram that encodes the global structure of the moduli space, as well as all symmetry enhancements and the loci where they occur. We find 107 points of maximal enhancement with 8 that are free of tachyons. The tachyon-free points each have positive cosmological constant. We determine the profile of the potential energy near each of these points and find that one is a maximum while three are saddle points. The remaining four live at the boundary of a tachyonic region in field space. In this way, we show that every point of maximal symmetry enhancement is unstable. We further find that the curvature of this stringy potential satisfies the de Sitter swampland conjecture. Finally, we discuss the implications for constructions of AdS 3 .