Early Universe with CMB Anisotropy

Abstract

Current cosmological observations are remarkably consistent with a concordance cosmology including an epoch of inflation in the very early universe. There is a tantalizing possibility that the ultra-high energy physics of the very early universe could be deduced from cosmological observations. In particular, the observed angular power spectrum of the CMB anisotropy is a convolution of the cosmological radiative transport kernel with the power spectrum of primordial perturbations. Exquisite measurements of the angular power spectrum over a wide range of multipoles from WMAP have opened up the possibility to deconvolve the primordial power spectrum for a given set of cosmological parameters. We present an update on our ongoing research program to recover the primordial power spectrum from CMB anisotropy. The robust features in the recovered primordial spectrum could be signatures of the physics behind inflation. Initial work towards mapping out the likelihood, ‘optimized’ over the unknown primordial spectrum, in the space the cosmological parameters reveal interesting results.