Hawking Says He Was Wrong About Black Holes
July 21, 2004
By THE ASSOCIATED PRESS
Filed at 4:39 p.m. ET
DUBLIN, Ireland (AP) -- Famed astrophysicist Stephen
Hawking said Wednesday that black holes, the mysterious
massive vortexes formed from collapsed stars, do not
destroy everything they consume and instead can fire out
matter and energy ``in a mangled form.''
Hawking's radical new thinking, presented in a paper to the
17th International Conference on General Relativity and
Gravitation in Dublin, capped his three-decade struggle to
explain an elemental paradox in scientific thinking: How
can black holes destroy all record of consumed matter and
energy, as Hawking long believed, when subatomic theory
says such elements must survive in some form?
Hawking's answer is that the black holes hold their
contents for eons but themselves eventually deteriorate and
die. As the black hole disintegrates, they send their
transformed contents back out into the infinite universal
horizons from which they came.
Previously, Hawking, 62, had held out the possibility that
disappearing matter travels into a new parallel universe
within the black hole -- the very stuff of most visionary
``There is no baby universe branching off, as I once
thought. The information remains firmly in our universe,''
Hawking said in a speech to about 800 physicists and other
scientists from 50 countries.
``I'm sorry to disappoint science fiction fans, but if
information is preserved, there is no possibility of using
black holes to travel to other universes,'' he said.
``If you jump into a black hole, your mass energy will be
returned to our universe, but in a mangled form, which
contains the information about what you were like, but in
an unrecognizable state,'' he said with a smile, sparking
laughter from the audience.
Hawking added, ``It is great to solve a problem that has
been troubling me for nearly 30 years, even though the
answer is less exciting than the alternative I suggested.''
In a humorous aside, Hawking settled a 7-year-old bet made
with Caltech astrophysicist John Preskill, who insisted in
1997 that matter consumed by black holes couldn't be
destroyed. He presented Preskill a favored reference work
``Total Baseball, The Ultimate Baseball Encyclopedia''
after having it specially flown over from the United
``I had great difficulty in finding one over here, so I
offered him an encyclopedia of cricket as an alternative,''
Hawking said, ``but John wouldn't be persuaded of the
superiority of cricket.''
Later, Preskill said he was very pleased to have won the
bet, but added: ``I'll be honest, I didn't understand the
talk.'' Like other scientists there, he said he looked
forward to reading the detailed paper that Hawking is
expected to publish next month.
Hawking pioneered the understanding of black holes -- the
matter-consuming vortexes created when stars collapse -- in
the mid-1970s. He has previously insisted that the holes
emit radiation but never cough up any trace of matter
consumed, a view that conflicts with subatomic theory and
its view that matter can never be completely destroyed.
Hawking, a mathematics professor at Cambridge University,
shot to international fame with his best-selling book ``A
Brief History of Time,'' which sought to explain to a
general audience the most complex aspects of how the
Despite being virtually paralyzed and forced to rely on a
wheelchair with amyotrophic lateral sclerosis since his
mid-20s, Hawking travels the world on speaking engagements.
He communicates by using a hand-held device to select words
on his wheelchair's computer screen, then sending them to a
The slow process of constructing answers meant that, in the
press conference that followed his paper, Hawking was able
to answer only two questions in a half-hour. The final
questioner asked him what problem he intended to tackle
next, now that he had solved the paradox of the black hole.
``I don't know,'' Hawking quickly replied, bringing the
house down with laughter.