December 05, 1993

Article at Toronto Star

The universe almost didn’t happen, says astrophysicist

U.S. astrophysicist George Smoot


SYDNEY, Australia - The Big Bang might have been the Big Fizzle.

The universe teetered on the very edge of not being born, said the man whose studies have provided more evidence for the fiery moment of creation known as the Big Bang.

Detailed analysis now shows that if matter in the first second after the Big Bang had expanded just a hundred thousand trillionth slower than it did, the world would not be here today, U.S. astrophysicist George Smoot says.

The Big Bang theory holds the universe was once compacted into a tiny, super-condensed dot which suddenly exploded and scattered matter through space. 

In April last year Smoot’s team at the University of California used a Cosmic Background Explorer (COBE) satellite to find ripples in the fabric of the universe - differences in the way matter is distributed that could only have arisen if the universe began in one explosion, the Big Bang.

Smoot, in Australia for talks with astronomers and to promote his new book Wrinkles in Time, said there were still problems with the theory.

“The Big Bang itself doesn’t explain why the universe is so big and so flat and why it’s so much the same in every way. It doesn’t explain how space came to be and how it came to be expanding,” he said in a recent interview.

Scientists also worry about missing matter - too few stars and too little interstellar dust is visible in the universe of today to make the Big Bang theory viable.

Theorists explain this by saying that up to 90 per cent of the universe is made of “dark matter,” chunks of shadowy matter floating between galaxies which are invisible in the black backdrop of space. Recent discoveries appear to support this.

“But if we don’t find the dark matter, and if the fluctuations we see don’t fit this model, then we need a new model,” Smoot said.

“The Big Bang itself is in good shape, it’s a question of how did it really begin, why is the universe expanding?”

In it he says that scientific data collated by his team and overseas collaborators over the past few years now points to a universe that came into being through more of an incredible coincidence than had been thought by scientists and theorists.

“By now it is clear that the minutest variation in the value of a series of fundamental properties of the universe would have resulted in no universe at all, or a very alien universe,” Smoot said.

Too slow an expansion by even the barest of margins would have resulted in all matter collapsing into itself long ago, while a faster expansion, even by one part in a million, would have excluded the formation of stars and planets, he said.

Cosmologists and astrophysicists have long been bewildered by the smoothness of the structure of the universe. The Big Bang theory requires that the fabric of the universe show unevenness.

Smoot found the ripples and bumps in the way matter is distributed, but the variations are so minute they are almost imperceptible. It took the COBE satellite a year of detailed sky surveying to detect them.

But some still have doubts the ripples are real.

Director Ron Ekers of the Australia Telescope National Facility, a centre for radioastronomy, said the data showing tiny variations in the way matter is distributed was only just above the background noise of the cosmos.

But Smoot said balloon studies in the U.S., Britain and Spain had verified his team’s results and that the satellite’s second year of data, now being prepared by his team, would strengthen the original conclusions.