Well, yesterday was quite a day, and I’m still sifting through the consequences.
First things first. As with all major claims of discovery, considerable caution is advised until the BICEP2 measurement has been verified by some other experiment. Moreover, even if the measurement is correct, one should not assume that the interpretation in terms of gravitational waves and inflation is correct; this requires more study and further confirmation.
The media is assuming BICEP2’s measurement is correct, and that the interpretation in terms of inflation is correct, but leading scientists are not so quick to rush to judgment, and are thinking things through carefully. Scientists are cautious not just because they’re trained to be thoughtful and careful but also because they’ve seen many claims of discovery withdrawn or discredited; discoveries are made when humans go where no one has previously gone, with technology that no one has previously used — and surprises, mistakes, and misinterpretations happen often.
But in this post, I’m going to assume assume assume that BICEP2’s results are correct, or essentially correct, and are being correctly interpreted. Let’s assume that [here’s a primer on yesterday’s result that defines these terms]
- they really have detected “B-mode polarization” in the “CMB” [Cosmic Microwave Background, the photons (particles of light) that are the ancient, cool glow leftover from the Hot Big Bang]
- that this B-mode polarization really is a sign of gravitational waves generated during a brief but dramatic period of cosmic inflation that immediately preceded the Hot Big Bang,
Then — IF BICEP2’s results were basically right and were being correctly interpreted concerning inflation — what would be the implications?
Well… Wow… They’d really be quite amazing. Continue reading