Stephen Hawking Master of the Universe 2/5

By Oxbridge Tours - Posted on 24 April 2012

 

Stephen Hawking Master of the Universe Part Two

 

Two years after Hawking’s Book was published his he and his wife jane separated. In 1995 he married his nurse Elaine Mason.

‘I am marrying the woman I love’ he said. And the world waited eagerly for his much waited theory of everything.

‘When the brief history of time came out I think physicist were fairly hopeful that we would have this theory of everything within a few decades.’

In 1998 there was certainly reason for optimism; only gravity had to be explained and brought into the fold. Back in the 1970’s Hawking has already given physics in inkling of how it might work.

‘By applying quantum mechanics to the edge of the black hole in the 1970’s I was able to revolutionise our understanding of them.’

Hawking had proved it was possible to unite the theories of the very large as originally proposed in Einstein’s theory of relativity, and blend in some the  theory of the very tiny. By joining the theories of the large and the tiny Hawking had utterly changed our picture of black holes. He showed they eat up our universe, but then explode, giving up cast amounts of energy that eventually forms new stars. Physicists were fascinated. It was as if Hawking had pulled down a wall, and suddenly the theorists of the very large and very small had something to talk to each other about.

If Hawking could find a connection between the large and the tiny in black holes there must be more. Surely a single theory of the universe could be found that would include how gravity works, both now and at the universes beginning – The race was on.

Hawking first became enthused about an idea called super symmetry – based on the notion that before the big bang when the universe was just a single point, everything included gravity was merged with perfect symmetry into one all mighty super force.

‘We think that at the instant of creation there was a super force, a master force, a single force the governed the properties of this spot like universe. Then the universe began to expand and the force cracked.’

When the universe began the super force was entirely symmetrical. It was made of the same stuff and all behaved in the same way, but as it expended this symmetry started to break. In the millisecond after the big bang forces flew off in all directions and the universe became messy and uneven. Gravity and all the other parts of nature we see to say are the irregular imperfect descendants of the original symmetry.

The theory of super symmetry solved part of the problem Hawking had with gravity. Now the whole of nature including gravity could be unified at the big bang with one set of equations. But the was still a problem; if gravity was unified with everything else at the big bang, why did it become so very weak afterward compared to the other forces.

The brightest minds like Hawking and Princeton professor Mark Yeilds were trying to work out how the perfection of super symmetry broke and ended up with the world we see today.

‘Imagine sitting down at the dinner table, there is a glass to your left and one to your right. The arrangement of the table then has a symmetry between left and right (at least for the glasses), it works fine if everybody picks up the glass on the right or left, but if they all pick different glasses it break the symmetry – this is ubiquitous in the real world both for electrons in a bit of iron and the universe settling down from the big bang.’

Explaining why the universe had settled down the way it had was the next problem Hawking had to solve. Super symmetry made lots of sense but there seemed to be no particular reason why gravity should end up so weak. Much work still needed to be done but Hawking’s ability to communicate was slowing down drastically. Today it is a constant effort.

Throughout the 90’s at only four words per minute Hawking worked away at the problem of Gravity but cutting edge Physics became increasingly dependant on complex maths – Hawking was relying on students and colleagues to perform computations.

The next big break through came not from Hawking but from a colleague, just down the corridor in Cambridge. Professor Michael Green is one of the big hitters in string theory; it suggests that all the particles and forces of nature are actually vibrating little string like objects and it seems to magically solve the problem of gravity that Hawking is struggling with.