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

4142.854 - 4166.974 Sean Carroll

If you impose these symmetries, so you protect the dark energy field from interacting with any other fields, there's one interaction that is still allowed that you can't rule out. And it is a very specific interaction between your dark energy field and photons, which are very common. And it has the following effect. As a photon travels through the dark energy, the photon has a polarization.