From branes at singularities to particle physics

by A. URANGA (CERN-TH)

Tuesday 30 May 2000, 14:00 → 14:15 Europe/Zurich

TH Auditorium (CERN)

The purpose of the talk is to construct explicit configurations of D3-branes in type IIB string theory (concretely, D3-branes at singularities), leading to world-volume field theories extremely similar to the MSSM. In particular, they produce SU(3)xSU(2)xU(1) gauge group, with three generations of quarks and leptons. I will also discuss how these configurations can be embedded in compact models preserving N=1 supersymmetry or breaking it in a hidden sector. These models provide explicit string theory realisations of the brane-world scenario, with the Standard Model sector embedded in a set of D3-branes. The construction of the models follows a bottom-up philosophy: In a first step one scans large families of singularities, and singles out those leading to phenomenological promising field theories. In a second step, one embeds such local structures in a global model, namely a compact space. Many phenomenological issues, like gauge coupling unification, proton stability, etc, are controlled by the structure of the singularity, and so are quite independent on the global structure of the compactification.