(AP) -- Cambridge University says physicist Stephen Hawking is still hospitalized but recovering from a chest infection.
The university said Wednesday that Hawking is "on the road to recovery" from the illness that has kept him at Addenbrooke's Hospital in Cambridge since earlier this week.
The 67-year-old scientist is well-known for his work on black holes and his best-selling 1988 book "A Brief History of Time."
Hawking has remained active although he was diagnosed at age 21 with ALS (amyotrophic lateral sclerosis), an incurable degenerative disorder also known as Lou Gehrig's disease.
He has been almost completely paralyzed for years and communicates through an electronic voice synthesizer activated by his fingers.
©2009 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.
Explore further: Explainer: How to solve a jewel heist (and why it takes so long)