Stephen William Hawking is an English theoretical physicist and cosmologist, whose scientific books and public appearances have made him an academic celebrity.The black hole information paradox results from the combination of quantum mechanics and general relativity. It suggests that physical information could disappear in a black hole, allowing many physical states to evolve into the same state. This is a contentious subject since it violates a commonly assumed tenet of science—that in principleThere are two main principles at work: quantum determinism, and reversibility. Quantum determinism means that given a present wave function, its future changes are uniquely determined by the evolution operator. Reversibility refers to the fact that the evolution operator has an inverse, meaning that the past wave functions are similarly unique. With quantum determinism, reversibility, and a conserved Liouville measure, the von Neumann entropy ought to be conserved, if coarse graining is ignored. complete information about a physical system at one point in time should determine its state at any other time