A Brief History of Time

Scientist and author Stephen Hawking is "very ill" and has been hospitalized, according to Cambridge University, where he is a professor.

Hawking, 67, is one of the world's most famous physicists and also a cosmologist, astronomer, and mathematician.

Wheelchair-bound Hawking is perhaps most famous for 'A Brief History of Time' which explored the origins of the universe in layman's terms, is considered a modern classic.

Hawking has Lou Gehrig's Disease (Amyotrophic Lateral Sclerosis, or ALS), which is usually fatal after three years. Hawking has survived for more than 40 years since his diagnosis.