On the road to discovery of relic gravitational waves: The TE and BB Correlations in the cosmic microwave background radiation

Understand

The detection of primordial gravitational waves is one of the biggest challenges of the present time.

• The existing (Wilkinson Microwave Anisotropy Probe) observations are helpful on the road to this goal, and the forthcoming experiments (Planck) are likely to complete this mission.
• We show that the 5-year Wilkinson Microwave Anisotropy Probe $TE$ data contains a hint of the presence of gravitational wave contribution.
• In terms of the parameter $R$, which gives the ratio of contributions from gravitational waves and density perturbations to the temperature quadrupole, the best-fit model produced $R=0.24$.