1:00pm Monday January 31 in 3 East - Theory Conference Room
We will discuss the generation of non-Gaussianities in Cosmic Microwave Background (CMB) temperature ansiotropies. For currently favored inflationary models, the primordial non-Gaussian contributions can be ignored, however, we show that a significant non-Gaussian contribution can exist in CMB data through late time effects and processes due to non-linear growth of perturbations. The non-Gaussianities arise through coupling between gravitational lensing, time dependent potentials through integrated Sachs-Wolfe effect, Doppler and Ostriker-Vishniac effects due to reionization, and large scale structure Sunyaev-Zel'dovich effect among many other possibilities. Given the distinct frequency dependance of SZ effect, the non-Gaussianities generated by SZ effect can be studied in detail using Planck data. Finally, we present several comsological uses of CMB bispectrum, the Fourier space analog of three point function.