T-branes and Yukawa couplings

  • Chan-Chi Chiou
  • Alon E. Faraggi
  • Radu Tatar
  • William Walters


We consider various configurations of T-branes which are non-abelian bound states of branes and were recently introduced by Cecotti, Cordova, Heckman and Vafa. They are a refinement of the concept of monodromic branes featured in phenomenological F-theory models. We are particularly interested in the T-branes corresponding to Z 3 and Z 4 monodromies, which are used to break E 7 or E 8 gauge groups to SU(5) GUT . Our results imply that the up-type and down-type Yukawa couplings for the breaking of E 7 are zero, whereas up-type and down-type Yukawa couplings, together with right handed neutrino Yukawas are non-zero for the case of the breaking of E 8. The dimension four proton decay mediating term is avoided in models with either E 7 or E 8 breaking.


F-Theory Intersecting branes models Supersymmetric gauge theory 


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Copyright information

© SISSA, Trieste, Italy 2011

Authors and Affiliations

  • Chan-Chi Chiou
    • 1
  • Alon E. Faraggi
    • 1
  • Radu Tatar
    • 1
  • William Walters
    • 1
  1. 1.Division of Theoretical Physics, Department of Mathematical SciencesThe University of LiverpoolLiverpoolU.K.

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