Towards a Non-Supersymmetric String Phenomenology

Abstract

Over the past three decades, considerable effort has been devoted to studying the rich and diverse phenomenologies of heterotic strings exhibiting spacetime supersymmetry. Unfortunately, during this same period, there has been relatively little work studying the phenomenologies associated with their non-supersymmetric counterparts. The primary reason for this relative lack of attention is the fact that strings without spacetime supersymmetry are generally unstable, exhibiting large one-loop dilaton tadpoles. In this paper, we demonstrate that this hurdle can be overcome in a class of tachyon-free four-dimensional string models realized through coordinate-dependent compactifications. Moreover, as we shall see, it is possible to construct models in this class whose low-lying states resemble the Standard Model (or even potential unified extensions thereof) --- all without any light superpartners, and indeed without supersymmetry at any energy scale. The existence of such models thus opens the door to general studies of non-supersymmetric string phenomenology, and in this paper we proceed to discuss a variety of theoretical and phenomenological issues associated with such non-supersymmetric strings. On the theoretical side, we discuss the finiteness properties of such strings, the general characteristics of their mass spectra, the magnitude and behavior of their one-loop cosmological constants, and their interpolation properties. By contrast, on the phenomenological side, the properties we discuss are more model-specific and include their construction techniques, their natural energy scales, their particle and charge assignments, and the magnitudes of their associated Yukawa couplings and scalar masses.

66 pages + 4 appendices, LaTeX, 9 figures, 11 tables

References in corpus (12)

• Statistics on the Heterotic Landscape: Gauge Groups and Cosmological Constants of Four-Dimensional Heterotic Strings
• A Supersymmetric One Higgs Doublet Model
• Non-supersymmetric heterotic model building
• Maximally Natural Supersymmetry
• Universality of Gauge Thresholds in Non-Supersymmetric Heterotic Vacua
• An Alternative for Moduli Stabilisation
• On the Low Energy Spectra of the Nonsupersymmetric Heterotic String Theories
• Intersecting Brane Worlds at One Loop
• Non-supersymmetric Tachyon-free Type-II and Type-I Closed Strings from RCFT
• Vacuum stability, string density of states and the Riemann zeta function
• Rare Flavor Processes in Maximally Natural Supersymmetry
• Classification of the Chiral Z_2 x Z_2 Heterotic String Models

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• Fermions and the Swampland
• Lie algebra lattices and strings on T-folds
• A Dynamical Mechanism for Large Volumes with Consistent Couplings
• Gravitational Threshold Corrections in Non-Supersymmetric Heterotic Strings
• Flavor from the double tetrahedral group without supersymmetry
• Dark Horse, Dark Matter: Revisiting the SO(16)x SO(16)' Nonsupersymmetric Model in the LHC and Dark Energy Era
• Spontaneous dark-matter mass generation along cosmological attractors in string theory
• $USp(32)$ Special Grand Unification
• Non-SUSY Gepner Models with Vanishing Cosmological Constant