Broadly speaking, there are two kinds of acting: character acting and lead acting. And in my life, to begin with, in the 1980s, it was all character acting. And then when, by fluke, through 'Four Weddings', I got into doing lead parts, it's a completely different thing.
Science is global. Einstein's equation E=mc2 has to reach everywhere. Science is a beautiful gift to humanity we should not distort it. Science does not differentiate between multiple races.