CMI Silver Jubilee Lecture

Tarun Souradeep, IUCAA, Pune

In pursuit of elusive cosmic gravitational waves

Tuesday, March 3, 2015

Abstract:

Exquisite measurements of temperature fluctuations and polarisation of the Cosmic Microwave Background (CMB) radiation have not only pinpointed a 'standard' model of cosmology, but have also been remarkably consistent with broad, generic expectations of an (postulated) epoch of inflation in the early universe. Same mechanism in inflation that produces the measured CMB anisotropy also produces a stochastic cosmic gravitational wave background. CMB B-mode polarisation measurements at an appropriate level of sensitivity and over a select angular scales holds the key to this promising probe of the early universe. I review the promise, struggle and challenges of this intense pursuit and describe the current status after recent results from Planck and BICEP and the future prospects.