I don't know how you guys can tie this with a girl. A girl would hardly be working on chaotic things in a love song. This song is about Stephen Hawking whom Thom Yorke was obsessed with maybe due to the fact that he has a physical problem too. Stephen Hawking is the sun, moon and the stars. He works on chaotic things. And he preaches that the world is going to end soon. In this song, Thom mocks the authority that Hawking tries to gain by his theories.