Definitely Elvis, but why did the playwright make the visitor Elvis?

May refer not only to his theory of relativity but also to imagination and creativity. As Einstein had quoted "Knowledge is limited. Imagination encircles the world"

Picasso in most of his paintings depicted unrecognisable individuals (Other than his self-portrait). He was mostly inspired by African masks and South Asian/ Egyptian style of dressing . Similarly the painting which Picasso will be painting in the future Les Demoiselles d'Avignon depicts the familiarity with something unrecognisable.