T-branes and monodromy

• Published in: The journal of high energy physics Vol. 2011; no. 7
• Main Authors: Cecotti, Sergio, Córdova, Clay, Heckman, Jonathan J., Vafa, Cumrun
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01-07-2011; Springer Nature B.V
• Subjects: Branes; Classical and Quantum Gravitation; Couplings; Eigenvalues; Elementary Particles; High energy physics; Phenomenology; Physics; Physics and Astronomy; Quantum Field Theories; Quantum Field Theory; Quantum Physics; Relativity Theory; String Theory; Subspaces; Topological Field Theories; D-branes; F-Theory; Supersymmetric gauge theory
• ISSN: 1029-8479; 1029-8479
• DOI: 10.1007/JHEP07(2011)030

We introduce T-branes, or “triangular branes”, which are novel non-abelian bound states of branes characterized by the condition that on some loci, their matrix of normal deformations, or Higgs field, is upper triangular. These configurations refine the notion of monodromic branes which have recently played a key role in F-theory phenomenology. We show how localized matter living on complex codimension one subspaces emerge, and explain how to compute their Yukawa couplings, which are localized in complex codimension two. Not only do T-branes clarify what is meant by brane monodromy, they also open up a vast array of new possibilities both for phenomenological constructions and for purely theoretical applications. We show that for a general T-brane, the eigenvalues of the Higgs field can fail to capture the spectrum of localized modes. In particular, this provides a method for evading some constraints on F-theory GUTs which have assumed that the spectral equation for the Higgs field completely determines a local model.