You are here: Home / Seminars / Seminar Database / Colloquium: Inflationary Gravitational Radiation and Microwave Background Polarization

Colloquium: Inflationary Gravitational Radiation and Microwave Background Polarization

Main Content

Arthur Kosowsky, University of Pittsburgh
11 December 2014 from 4:00 PM to 5:00 PM
117 Osmond Laboratory
Contact Name
Eugenio Bianchi
Contact Phone
(814) 865-3147
Add event to calendar

We live in a universe whose properties are remarkably well described by a

very early epoch of accelerating expansion, termed inflation. One generic
prediction of inflation is a relic background of stochastic gravitational
radiation. These tensor metric perturbations leave a distinctive imprint in the polarization
of the microwave background. In March 2014, the BICEP experiment at the
South Pole announced the detection of this signal for the first time, although
subsequent analysis cast doubt on whether polarized emission from dust
in the Milky Way galaxy might be contaminating the signal. I will review the
current state of observations and give an overview of upcoming observational
efforts which will definitively distinguish the cosmological and galactic signals. 
If the BICEP signal has a significant component due to inflation, 
this opens the door to the remarkable
possibility of detecting the gravitational radiation background directly with a 
space-based laser interferometer. Such a measurement would provide a precision
probe of physics at energy scales a trillion times higher than those at
terrestrial accelerators.