General relativity is insane and was definitely a bit ahead of its time. It took decades before we could test many of the implications. Special relativity was

General relativity is insane and was definitely a bit ahead of its time. It took decades before we could test many of the implications. Special relativity was being worked on by several people contemporaneously. The fact that it is called "Lorentz Contraction" should tell you that other people were working on it.