MR. SUVODIP MUKHERJEE

With the recent constraint on inflationary gravitational wave from BICEP-2 and Planck, CMB missions have opened a new window in the inflationary epoch of the Universe. Measurement of the amplitude and spectral index for tensor perturbation will improve our understanding on the nature of inflation. The feasibility of power law kind inflationary model with the current measurements will be discussed by the speaker. However, the measurement of the tensor to scalar ratio assumes the CMB field to be isotropic. The recent measurements from WMAP and Planck indicates the CMB field to be non-isotropic at large angular scale and its implications on the measurement of tensor to scalar ratio need to be considered. In this talk, the speaker will introduce a mixed modulation model which explains the salient features of the hemispherical asymmetry by considering an isotropy violated Stochastic Gravitational Wave Background (SGWB) of the Universe and will show the imprint of this model in the current observations. The unique signatures of this model can be perceived in the B mode polarization of CMB. The techniques to measure these signatures from BICEP, Planck and PRISM will be discussed in the talk.