[Cosmo-torun] proof for gravitational waves?

Hi all, Hot news in media, according to which there is detection of gravitational waves by the BICEP2 experiment. It is something about messuring b-mode polarisation of CMB, that's all what I undersdand. Links: media: http://news.stanford.edu/news/2014/march/physics-cosmic-inflation-031714.htm... project: http://bicepkeck.org/ paper:http://bicepkeck.org/b2_respap_arxiv_v1.pdf Can we say it is a direct evidence for gravitational waves or rather it should be said indirect? Pozdr, Tomek