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From Associated Press:
CAMBRIDGE, England - Cosmologist Stephen Hawking will retire from his prestigious post at Cambridge University next year, but intends to continue his exploration of time and space.

Hawking, 66, is Lucasian Professor of Mathematics, a title once held by the great 18th century physicist Isaac Newton. The university said Friday that he would step down at the end of the academic year in September, but would continue working as Emeritus Lucasian Professor of Mathematics.

"We look forward to him continuing his academic work at the Department of Applied Mathematics and Theoretical Physics, playing a leading role in research in cosmology and gravitation," said Professor Peter Haynes, who heads the department.

Hawking became a scientific celebrity through his theories on black holes and the nature of time, work that he carried on despite becoming paralyzed by motor neurone disease.

University policy is that officeholders must retire at the end of the academic year in which they become 67. Hawking will reach that milestone on Jan. 8.

The Lucasian professorship post was founded in 1663 by Henry Lucas, who left his 4,000 books and land expected to yield 100 pounds a year to the university. King Charles II officially established the position in 1664.

Sir Isaac Newton was the second to hold the post. Paul Dirac, a specialist in quantum mechanics who predicted the existence of positron particles, had the title from 1932 to 1969.

Hawking was appointed to the chair in 1979.

His 1988 book, "A Brief History of Time," was an international best-seller; "A Briefer History of Time," intended to be more accessible, followed in 2005.

"George's Secret Key to the Universe," co-authored with Hawking's daughter Lucy, was published last year for the children's market.

Hawking first earned prominence for his theoretical work on black holes. Disproving the belief that black holes are so dense that nothing could escape their gravitational pull, he showed that black holes leak a tiny bit of light and other types of radiation, now known as "Hawking radiation."

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