The reason some scientists complained that Einstein’s proof wasn’t rigorous was because it?
A was published after Einstein’s death in 1955.
B was obviously incorrect.
C didn’t describe particles moving at all speeds.
D didn’t list the sources he used.
The correct answer is C didn’t describe particles moving at all speeds.
Explanation: Some scientists felt that Einstein’s proof lacked rigor because it did not adequately account for particles moving at all speeds, especially in the context of relativistic physics. Einstein’s theories primarily addressed conditions at relativistic speeds, and critics believed that the proofs required a more comprehensive examination of all potential speeds to be deemed rigorous.