This simple insight amounts to a revolution in physics. It resolves an inconsistency accepted by Einstein in the absence of Noether’s theorem in 1907: that c were reduced downstairs in a constantly accelerating long rocketship in outer space.

Noether allows you to see what happens. She discovered “global conservation of angular momentum in nature” as is well known in 1916.

Take a frictionless bicycle wheel that is suspended from its hub, and lower it and then pull it back up again. What happens if angular momentum is constant all the time as she showed?

Answer: The rotation rate of this “clock” must go down reversibly like that of any other clock. But since angular momentum is conserved (Noether), the other two components in angular momentum besides rotation rate (i.e. mass and radius) cannot both remain unchanged.

This is a wonderful new result enabled by Emmy Noether.