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| Stephen Hawking from the University of
Cambridge, one of the world's leading theoretical physicists, addresses
the audience via a computer during a ceremony at the Great Hall of the
People in Beijing, June 19, 2006. [newsphoto]
| BEIJING, June 19 (Xinhua) -- Is the universe eternal,
or did it have a beginning? World-renowned physicist Stephen Hawking gave his
answer to a large audience in Beijing on Monday.
He gave a 45-minute multimedia
presentation at the Great Hall of People on the occasion of the International
Conference on String Theory 2006, which traced the development of theories on
cosmic origins, beginning with African creation myths.
He described -- through his electronic speech
synthesizer -- how the general theory of relativity and the discovery of the
expansion of the universe provoked conceptual changes, which meant that the idea
of an ever-existing, ever-lasting universe was no longer tenable.
The 64-year-old scientist and author of the global
best-seller "A Brief History of Time" uses a wheelchair and communicates with
the help of a computer because he suffers from a neurological disorder called
amyotrophic lateral sclerosis, or ALS.
One of the best-known theoretical physicists of his
generation, Hawking has done groundbreaking research on black holes and the
origins of the universe, proposing that space and time have no beginning and no
end.
The image Hawking drew of this process was that of
bubbles appearing and bursting, corresponding to mini universes that expand and
collapse. Only those which grew to a certain size would be safe from collapse
and would continue to expand at an ever increasing rate.
The theorem which he and Prof. Roger Penrose
developed in 1970 said that general relativity predicated that the universe and
time itself would begin with the big bang and that time would come to an end in
black holes.
"One can get rid of the problem of time having a
beginning in a similar way in which we got rid of the edge of the world," said
Hawking.
Likening the beginning of the universe to the South
Pole, with degrees of latitude playing the role of time, Hawking explained that
the universe would start as a point at the South Pole.
"As one moves north, the circles of constant
latitude, representing the size of the universe, would expand. To ask what
happened before the beginning of the universe would become a meaningless
question because there is nothing south of the South Pole," Hawking said.
In this view, the beginning of the universe would be
governed by the laws of science: the creation of the universe would be down to
spontaneous quantum creation.
"Cosmology is a very exciting and active subject. We are getting close to answering the age-old questions: Why are we here? Where did we come from?" Hawking said. Enditem
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