Albert Einstein, one of the most famous scientists on earth, no one understands him but everyone loves him. Even after his death his fame escalated until he became a huge legend that does not know between its true lines the true of the fake.
No one knows exactly why Albert Einstein is so famous, although there are some interpretations, but in the end, an ordinary citizen would not be interested in that quantum leap in the way physics understands abstract terms. Anyone with sufficient training in science can easily understand the theory, and there is nothing surprising or mysterious about it.