Oil sketch by Yolanda Sonnabend for a portrait in the National Portrait Gallery, London. Stephen Hawking (b 1942) is Lucasian Professor of Mathematics at Cambridge University, and the author of the bestselling book on big bang theory and black holes, 'A Brief History of Time', (1988). Considered to be one of the greatest physicists since Albert Einstein, Hawking developed Amyotrophic Lateral Schlerosis in early adulthood. In 1998 he published 'The Universe in a Nutshell'.
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