Black holes may be less 'black' than we thought

But a Columbia University (New York) researcher is casting doubt on that assumption. 

Maulik Parikh makes the argument in an essay that last May won an annual competition organized by the U.S. Gravity Research Foundation -- a well known contest that the famed physicist Stephen Hawking has won five times.

Hawking himself changed the traditional view of black holes decades ago when he showed that these objects, contrary to wisdom previously prevailing, actually give off light. 

But the light was still supposed to have exhibited what's called a thermal spectrum. This means in effect that very different types of objects can emit the same radiation, so the light tells you nothing about what they consist of. Parikh's essay contains equations that contradict that contention, indicating black holes can emit a non-thermal spectrum -- and thus information.

—EJL