FILE - In this Thursday, April 26, 2007 file photo physicist Stephen Hawking answers questions during an interview in Orlando, Fla. Famed mathematician Stephen Hawking has been rushed to a hospital and is seriously ill, Cambridge University said Monday April 20, 2009 .The university said Hawking has been fighting a chest infection for several weeks, and was being treated at Addenbrooke's Hospital in Cambridge, the university city north of London. (AP Photo/John Raoux. File )

(AP) -- The family of physicist Stephen Hawking expects him to recover fully from a chest infection that has left him hospitalized, Cambridge University said Tuesday.

Hawking "was being kept in observation" at Addenbrooke's hospital after being admitted Monday.

"He is comfortable and his family is looking forward to him making a full recovery," Cambridge said in a statement.

Hawking, 67, gained renown for his work on black holes and has remained active despite being diagnosed at age 21 with ALS, (amyotrophic lateral sclerosis), an incurable degenerative disorder also known as Lou Gehrig's disease.

Hawking has been almost entirely paralyzed for years and communicates through an electronic voice synthesizer activated by his fingers.

Hawking was involved in the search for the great goal of physics - a "unified theory" - which would resolve contradictions between Albert Einstein's General , which describes the laws of gravity that govern the motion of large objects like planets, and the Theory of , which deals with the world of subatomic particles.

"A complete, consistent unified theory is only the first step: our goal is a complete understanding of the events around us, and of our own existence," he wrote in his best-selling book, "A Brief History of Time," published in 1988.

In the sequel "The Universe in a Nutshell," published in 2001, Hawking ventured into concepts like supergravity, naked singularities and the possibility of a universe with 11 dimensions.

He announced last year that he would step down from his post as Lucasian Professor of Mathematics, a title once held by the great 18th-century physicist . However, the university said Monday Hawking intended to continue working as Emeritus Lucasian Professor of Mathematics.

The illness, which Hawking has been fighting for several weeks, had caused him to cancel an appearance at Arizona State University on April 6.

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On the Net: http://www.hawking.org.uk

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