Guys, I have started reading Special Relativity and used the Feynman Lectures as my starting point. As I noted, he started well with the concept of ether and told about Michelson-Morley experiment. There, to explain the results of experiment, he told Lorentz Contraction and supposed it to be true whatsoever. Then came Poincare's Hypothesis and from there on he continued to develop the the theory taking Lorentz Contraction and Poincare's Hypothesis as postulates. Nowhere did he gave any sign whether the concept of ether is correct or incorrect. So, I want to know whether there is any proof that the concept of ether is falty? And moreover what is the proof of Lorentz Contraction?