What made him an a$$hole? I’m not even that familiar with his background.
He apparently was more a theorist than a mathematician, his math was sloppy and he made a lot of mistakes over the years. There's a theory that his 1st wife was the one who crunched all the numbers for his famous theories.
People also covered up for his mistakes a lot over the years.
He got a lot of credit for other people's work that he used for relativity (he didn't come up with space time and disagreed with the guy who used his formulaes to theorize black holes).
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