## Failure of the equivalence principle?

Here’s an interesting physics tidbit, to close out a long break from the science on this site: a couple of scientists claim to have proposed an experiment which theoretically should be able to distinguish between gravitational and inertial accelerations. This would break one of the most widely accepted laws of physics, the equivalence principle of gravitational and inertial masses — in other words, the belief that the $$m$$ in $$F=ma$$ is the same as the one in $$F=-GMm/r^2$$ is now being challenged.