Dent, James BKrauss, LawrenceSabharwal, SubirVachaspati, Tanmay2015-12-131550-7998http://hdl.handle.net/1885/75037It has been shown that a cosmological background with an anisotropic stress tensor, appropriate for a free-streaming thermal neutrino background, can damp primordial gravitational waves after they enter the horizon, and can thus affect the cosmic microwavAuthor/s retain copyright201310.1103/PhysRevD.88.0840082015-12-11