Although widely held as the dominant cosmological
theory, growing numbers of scientists are looking at
the unanswered questions behind the 'big bang'.
Image: Istockphoto

We are, according to big bang theory, travelling through space and time, expanding with the universe like surfers riding a big wave, or sultanas rising inside a cake mix.

Since everything, including stars and galaxies, planets, sultanas even, is moving away from the big bang that created the universe up to 14 billion years ago, it figures that if you could rewind the cosmic clock, everything would meet back at a point the size of an atom - the so-called singularity thought to exist inside black holes.

What caused this ‘seed’ of matter and energy, time and space, to expand into what we observe in space today remains a mystery.

Straightforward? Not for a growing number of scientists who question the cosmological mainstream and accuse it of ‘fudging’ what cannot be confirmed through observational data.

University of WA physicist John Hartnett is one of these scientists investigating alternative scenarios to how the universe formed.

"We can't discount some of the incredible work that has been done," he says.

"But some of the observational data to support the big bang is highly questionable."

Professor Hartnett is one of many scientists who feel debate on alternative theories has been largely sidelined or shut down by the dominance of the big bang cosmological model.

He says that the singularity at the start of the universe is one of the biggest single problems with the big bang model.

"It's not a black hole, it has no event horizon, and it can't start expanding because it is supposed to be a super stable state of matter.

"There's an assumption that it somehow starts expanding. And that when it starts we can use physics we know. You have to start at 10 to the minus 43 of a second after the actual expansion of the universe begins before you can start using physics."

There is no physics to explain what triggered its existence. Prior to the singularity, nothing existed in the ‘void’ around it, not space, time, matter or energy. Scientists do not know where it came from.

Another inconsistency is the cosmic microwave background radiation discovered in 1964. The radiation, measured at 2.73K or about minus 270C, is apparently the remnant glow from the big bang.

In 1992, the NASA satellite COBE (or Cosmic Background Explorer) discovered the ‘ripples’, or clumps of matter and energy, in the background radiation. This was regarded as the clincher guaranteeing the supremacy of the big bang theory.

The COBE results suggested the radiation had been produced in the very early stages of the universe, about 300,000 years after the singularity.

"But the background radiation is not in the background in all galaxy clusters, which it should be if it comes from the big bang event," Professor Hartnett says.

"Theories need evidence to back them up but a lot of the evidence supporting the big bang theory does not stack up."

Some cosmic cracks in the big bang model:

• In 2003, a survey of galaxy clusters using data from the ROSAT X-ray satellite showed what seemed to be a huge concentration of matter about 12 billion light years across. A concentration of this size could not possibly have formed during the time since the big bang nearly 14 billion years ago. These clusters of tens to hundreds of thousands stars also appear older than the universe.
• In 2004, discoveries announced at the January meeting of the American Astronomical Society showed that the universe looks very similar billions of years ago to its appearance today, contradicting the big bang idea that the universe looked different in the past. Galaxies created 10 billion years ago appeared to have a similar distribution of stellar ages and spectrum of chemicals produced by stars as our present-day galaxy. According to the big bang model, these galaxies should appear much younger, with fewer heavy metals and mostly young stars.
• A fundamental problem with big bang theory is the weakness of the gravitational force between stars and galaxies. ‘Dark’ matter - which has never been detected - is needed to explain why so much of the universe (98 percent) is missing, or cannot be seen.