Although September 11 was horrible it didn't threaten the survival of the human race like nuclear weapons do.
Stephen William Hawking (born 8 January 1942, died 14 March 2018) was an English theoretical physicist, cosmologist, author and Director of Research at the Centre for Theoretical Cosmology within the University of Cambridge. Hawking was the first to set forth a theory of cosmology explained by a union of the general theory of relativity and quantum mechanics. He is a vigorous supporter of the many-worlds interpretation of quantum mechanics.
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