Sure, the Big Bang is great. Going back to very early times, it tells us the Universe was in a hot, dense state, where even the possibility of forming neutral atoms was impossible due to the incredible energies of the Universe at that time. The patterns of fluctuations that are left over from that time give us insight into the primordial density fluctuations that our Universe was born with.
But there's an additional signature encoded in this radiation, one that's much more difficult to extract: polarization. While most of the polarization signal that's present will be due to the density fluctuations themselves, there's a way to extract even more information about a new phenomenon: gravitational waves that were present from the epoch of cosmic inflation!
Great post! Very well explained, much more depth than anything I have seen elsewhere. More, more!
Agree with #1, very well written. Extremely informative. This is the first time I heard someone actually explain what b-mode is (the magnetic component of EM)... which is awesome. Also, the process of how they are extracted from the rest of data is explained. I wish there were more articles from Amanda.
Instead of just pasting basics, she actually took the time to explain how the whole process works, both in universe, as well from the experiment and data analysis, and yet managed to do so, so that it's understoon without need to formula. Truly excellent post!