Jacques Salomon Hadamard was a French mathematician. Among his contributions, Hadamard proved the prime number theorem and has his name on the Hadamard product (element-wise product of matrices) and the Hadamard matrices. Even though he didn’t work in quantum mechanics, Hadamard gates are also named after him because its matricial representation is a Hadamard matrix. Being of Jewish descent, in 1941 Hadamard left France for the United States during the antisemitic Vichy government. He retur...
