The Unwritten Laws of Physics for Black Women

She decided to study physics. It was, in a way, good timing—a Black American woman had just become the first of her kind to earn a physics PhD, back in Greene-Johnson’s home state. At Stanford, Greene-Johnson was the only Black student in her major, but that didn’t surprise her. What did was the presence of six Black PhD students in the department. “I had brothers and sisters galore,” she told me.