My research interest focused on understanding a possible new physics beyond the standard model (SM). I have investigated the supersymmetric extensions of the SM and their potential signatures at colliders, in astrophysical observations and cosmological implications. With the wealth of experimental data coming from the B-factories, the SM is subject to stringent tests. We studied the question of whether supersymmetry can significantly modify the CP asymmetry in B-decays compared to the SM picture. We also studied the hybrid inflationary scenario in supersymmetric extension of the SM model, taking into account the new WMAP results and computing the corresponding spectral index of the density perturbation. We performed a complete analysis for the minimal extension of the SM gauge symmetry that can accommodate the phenomenon of neutrino flavour oscillations which has been confirmed by many experiments.

Supersymmetry until very recently was thought to be the only way to explain physics at the TeV scale, and there was a lot of excitement when it was first suggested that large extra dimensions provide an alternative way to address the origin of the TeV scale. We explored the particle phenomenology and also the cosmological implication of the warped extra dimensional model, in particular what is known as Randall-Sundurm Scenario. Recent developments in String Theory point at a scenario where the SM fields are constrained to live in a lower dimensional surface - a brane - of the higher dimensional space time while gravity lives in the full space time. This means we do not yet know where the string scale is, and it could be anywhere from the TeV scale to the Planck scale. We were interested in studying the phenomenological implications of such brane-scenario inspired models with and without fluxes. The analysis of the supersymmetry breaking, flavour structure, and CP violation in this class of model could be quite different from the well known result obtained in the heterotic string picture.