Stephen Hawking is a scientist.
The many-worlds interpretation is an interpretation of quantum mechanics that asserts the objective reality of the universal wavefunction and denies the actuality of wavefunction collapse . Quantum mechanics ( QM ; also known as quantum physics or quantum theory ) , including quantum field theory , is a branch of physics which is the fundamental theory of nature at small scales and low energy levels of atoms and subatomic particles . Stephen William Hawking , ( born 8 January 1942 ) is an English theoretical physicist , cosmologist , author and Director of Research at the Centre for Theoretical Cosmology within the University of Cambridge . He is a vigorous supporter of the many-worlds interpretation of quantum mechanics .