303 | AMA | February 2025

6576.523 - 6602.283 Sean Carroll

Even though there is not absolutely a reference frame in physics, there is approximately a rest frame in the universe where stars and galaxies typically move at about one one-thousandth the speed of light with respect to each other. So the Doppler effect is actually just not very big. There are circumstances in which it matters. In fact, there's a phenomenon called the finger of God.