Exotica and discreteness in the classification of string spectra

4th Symposium on Prospects in the Physics of Discrete Symmetries

Sonmez, Hasan^1

Department of Mathematical Sciences, University of Liverpool, Liverpool

L69 7ZL, United Kingdom^1

关键词: Algebraic expression;    Basis vector;    Discrete symmetry;    Heterotic strings;    Large spaces;    Partition functions;    Projection coefficients;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/631/1/012081/pdf
DOI  :  10.1088/1742-6596/631/1/012081

来源: IOP

【 摘 要 】

I discuss the existence of discrete properties in the landscape of free fermionic heterotic-string vacua that were discovered via their classification by SO(10) GUT models and its subgroups such as the Pati-Salam, Flipped SU(5) and SU(4) × SU(2) × U(1) models. The classification is carried out by fixing a set of basis vectors and varying the GGSO projection coefficients entering the one-loop partition function. The analysis of the models is facilitated by deriving algebraic expressions for the GSO projections that enable a computerised analysis of the entire string spectrum and the scanning of large spaces of vacua. The analysis reveals discrete symmetries like the spinor-vector duality observed at the SO(10) level and the existence of exophobic Pati-Salam vacua. Contrary to the Pati-Salam case the classification shows that there are no exophobic Flipped SU(5) vacua with an odd number of generations. It is observed that the SU(4) × SU(2) × U(1) models are substantially more constrained.