South Pole Telescope detects B-mode polarization

Nature : The cosmic microwave background is the residual thermal radiation from the Big Bang. It exhibits two types of polarization: E mode and B mode. Because B modes give off a very small signal with an amplitude of at most 0.1 μK, they had until now only been predicted. That changed earlier this week when researchers using the South Pole Telescope announced the first detection of gravitational lensing B modes. The discovery is important for particle physicists, who hope to use the signals to determine the matter content of the universe and calculate the masses of the three types of neutrinos. In addition, the study of B-mode signals could advance the field of cosmology by confirming cosmic inflation—the rapid expansion of the early universe following the Big Bang.