#428 – Sean Carroll: General Relativity, Quantum Mechanics, Black Holes & Aliens

4183.212 - 4207.229 Sean Carroll

But if you want to roughly fit the data, you can predict how much polarization rotation there should be. A couple of degrees, okay? Not that much. So that's very hard to detect. People have been trying to do it. Right now, literally, we're on the edge of either being able to detect it or rule it out using the cosmic microwave background. And there is just, you know, truth in advertising.