Henry Ford was an American industrialist. And he developed and manufactured the first automobile that many middle class Americans could afford Albert Einstein was a German-born theoretical physicist. He developed the general theory of relativity, one of the two pillars of modern physics.
It is known as civic or civil inattention. It is the method whereby strangers who are in close vicinity exhibit that they are mindful to one another without imposing on each other - an acknowledgment of the claims of others in terms of public space and their own personal space.