Investigation on String Vacua

The research will be in the area of superstring theory and phenomenology. His research will focus on
the properties of (2,0) heterotic string compactications and in particular on their moduli spaces.
A convenient tool for the exploration of the moduli spaces of (2,0) heterotic string compactica-
tions is the spinor-vector duality, which can be seen to arise from the breaking of (2,2) world-sheet
supersymmetry to (2,0). While the moduli spaces of (2,0) are poorly understood, the moduli spaces
of the (2,2) models have been studied extensively. Hence, the spinor-vector duality provides a guide
to explore the moduli spaces of the (2,0) vacua before and after the breaking. Mr Diaz will study
the implications of the spinor-vector duality in relation to modular symmetries that underlie the
string partition functions. He will further study aspects relating to duality symmetries in string
theory and how they relate to observational data. He will study interpolations of 2D MSDS string
partition functions to 4D chiral partition functions that are related to quasi-realistic string vacua.
The MSDS string partition functions have been studied in connection with the string cosmology
scenarios developed by the group in Ecole Normal Superier in Paris, whereas the 4D chiral partition
functions are associated with the quasi-realistic free fermionic models. The aim of this project is
to incorporate the phenomenological string models in the string cosmology scenarios and to explore
scenarios for string vacuum selection. Mr Diaz will study the problem of Supersymmetry breaking
in string theory using the Scherk-Schwarz mechanism as well as gaugino condensation and will ex-
tract prediction for the supersymmetric spectrum.