Regular Article - Theoretical Physics
Is the spectrum of gravitational waves the “Holy Grail” of inflation?
Department of Physics, McGill University, Montréal, QC, H3A 2T8, Canada
* e-mail: email@example.com
Accepted: 16 April 2019
Published online: 6 May 2019
It is often said that detecting a spectrum of primordial gravitational waves via observing B-mode polarization of the Cosmic Microwave Background is the “Holy Grail” of inflation. The purpose of this short note is to point out that it is indeed of immense scientific interest to search for a signal of gravitational waves in B-mode polarization. However, rather than proving that inflation is the right paradigm of early universe cosmology, a positive signal of direct primordial B-mode polarization might well be due to other sources than inflation. In fact, a careful characterization of the spectrum of B-mode polarization might even falsify the inflationary paradigm.
© The Author(s), 2019