Statistics on the heterotic landscape: Gauge groups and cosmological constants of four-dimensional heterotic strings

Journal Article · Mon May 15 04:00:00 EDT 2006 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PhysRevD.73.106010· OSTI ID:20774755

Dienes, Keith R ^[1]

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1. Department of Physics, University of Arizona, Tucson, Arizona 85721 (United States)

Recent developments in string theory have reinforced the notion that the space of stable supersymmetric and nonsupersymmetric string vacua fills out a landscape whose features are largely unknown. It is then hoped that progress in extracting phenomenological predictions from string theory--such as correlations between gauge groups, matter representations, potential values of the cosmological constant, and so forth--can be achieved through statistical studies of these vacua. To date, most of the efforts in these directions have focused on type I vacua. In this note, we present the first results of a statistical study of the heterotic landscape, focusing on more than 10{sup 5} explicit nonsupersymmetric tachyon-free heterotic string vacua and their associated gauge groups and one-loop cosmological constants. Although this study has several important limitations, we find a number of intriguing features which may be relevant for the heterotic landscape as a whole. These features include different probabilities and correlations for different possible gauge groups as functions of the number of orbifold twists. We also find a vast degeneracy amongst nonsupersymmetric string models, leading to a severe reduction in the number of realizable values of the cosmological constant as compared with naieve expectations. Finally, we find strong correlations between cosmological constants and gauge groups which suggest that heterotic string models with extremely small cosmological constants are overwhelmingly more likely to exhibit the standard model gauge group at the string scale than any of its grand-unified extensions. In all cases, heterotic world sheet symmetries such as modular invariance provide important constraints that do not appear in corresponding studies of type I vacua.

• OSTI ID: 20774755
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 10 Vol. 73; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
CORRELATIONS
COSMOLOGICAL CONSTANT
COSMOLOGY
POTENTIALS
PROBABILITY
SPACE
STANDARD MODEL
STATISTICS
SUPERSTRING MODELS
SUPERSYMMETRY
VACUUM STATES