Stephen Hawking’s office on the ground floor of a modern academic block in Cambridge is a surprisingly plush affair, complete with leather furniture and flourishing potted plants. Contrasting the traditional décor is a Homer Simpson clock on one wall, and on another, a carefully doctored photograph showing Marilyn Monroe posing with Hawking in his wheelchair.
These are old favourites belonging to the world’s most famous living scientist. Recently, however, an intriguing new set of pictures has been given pride of place: photographs of Hawking, a beaming grin fixed on his face, hovering in mid-air during a recent zero-gravity flight on a specially modified Boeing 727. The scientist experienced more than four minutes gravity-free flight is eagerly anticipating another shot, he says.
“It was amazing. The zero-g part was wonderful, and the high-g part was no problem. I could have gone on and on. Space, here I come,” he says, in his trademark computer-synthesised voice, replete with a very un-British American accent.
The wheelchair-bound physicist is not joking either. Hawking has teamed up with British entrepreneur Richard Branson to fly on one of the first flights by Virgin Galactic, whose space-planes are set to hurl passengers to altitudes of 120 km (75 miles) by 2009. At that height – lingering on the very fringes of space – passengers will experience even longer periods of weightlessness, possibly up to half an hour.
For Hawking, captive for so long in his wheelchair, a flight will bring further relief from his confinement. More importantly, it will give the public a clear signal of his belief that Homo sapiens’ future lies with interplanetary travel. “I think the survival of the human race will depend on its ability to find new homes elsewhere in the universe because there’s an increasing risk that a disaster will destroy Earth,” he argues. “I want to raise public awareness for space flight.”
Escape to the stars: it sounds melodramatic. But Hawking is serious. Mankind’s hopes of survival depend on us learning how to leave our planet which we are now destroying, he says. The clock is ticking. “We are now standing at the brink of a second nuclear age and a period of unprecedented climate change.” Even worse is the prospect of terrorists misusing genetic science to create viruses that could wipe out our species.
In short, Hawking’s view of the future is not an optimistic one. But what could one expect? The Cambridge physicist has had to endure decades of severe physical incapacity. As such, a harsh outlook on life is scarcely surprising.
Stephen William Hawking was born on 8 January, 1942 — 300 years to the day after the death of another great physicist, Galileo. He grew up, with a brother and two sisters, in middle-class St Albans, north-west of London. It was a safe life tempered by his parents’ mild eccentricity — the family car was a black London taxi and holidays were taken in a gypsy caravan. His father, Frank, was a medical researcher while his mother, Isobel — who is still alive — was a liberal, a free-thinker, and an enduring influence.
At the local public school, Hawking was considered a swot, shunning pop music for jazz, classical music, and debating. He also demonstrated an uncanny ability to visualise solutions to complex problems, without calculation or experiment, a talent that would prove invaluable in later years. Hawking won a scholarship to University College, Oxford, and in 1962 gained a first in physics, moving on to Cambridge to study cosmology.
In those day, the Big Bang theory of the Universe’s birth was only slowly gaining acceptance by astronomers. It was evident that galaxies were flying away from each other because the entire Universe had abruptly exploded into existence some 15,000-million-odd years ago, it was argued. But some scientists disliked this notion. It was simply too crude. In particular, a group of Russian scientists opposed the idea that the entire Universe had erupted from a single point, or singularity, and claimed they could show that it had merely contracted from a previous expanded condition to a smaller, but not infinitely small, state before expanding again.
“I did not like this so-called proof,” says Hawking. So he and a fellow Cambridge cosmologist, Roger Penrose, carried out a series of elegant calculations that showed that the idea of a cosmic singularity was correct. “The Universe began from a single, infinitely dense point where time had its beginning.” The young physicist had begun to make his mark.
Around this time Hawking found his movements were getting clumsy. Then his father noticed his lack of co-ordination and took his son for medical tests. The results were grim. “I gathered [that the doctors] expected it to get worse and there was nothing they could do except give me vitamins,” says Hawking. Eventually specialists put a name to his condition: amyotrophic lateral sclerosis, sometimes known as Lou Gehrig’s disease, a type of motor neurone disease which strips sufferers of their muscle power and usually ends in premature death.
Hawking plunged into a deep depression, staying up late at night listening to his beloved Wagner. However, there was no drink, he stresses. Contrary to many newspaper reports, he sought no solace in alcohol. Instead he found comfort with an old friend, Jane Wilde. They fell in love and decided to marry. “That engagement changed my life,” recalls Hawking. “It gave me something to live for.”
Within a few years, Hawking was confined to a wheelchair and was becoming increasingly reliant on help from others. But although his body was trapped, his intellect continued to roam. In one sense, he was lucky; his was a uniquely cerebral profession. He was a theorist and so did not have to carry out experiments in laboratories. So Hawking began thinking about black holes, the remains of collapsed stars that are so dense not even light can escape them. It was thought these stellar graveyards would inexorably increase in number as the Universe aged. Slowly the lights would go out across the cosmos as matter was sucked into the bottomless voids of more and more black holes.
But the idea nagged at Hawking. In 1974 he made a series of calculations that showed in some cases a black hole could actually radiate energy, contradicting the common conception that they were a one way street. Hawking reckoned the black hole would get smaller and smaller until it reached the size of an atomic nucleus, though still weighing an impressive 1,000 to 100,000,000 tonnes. Then it would erupt in a vast explosion.
This notion went down pretty badly at first, as Jane Hawking recalls in her newly-released Travelling to Infinity: My Life with Stephen. She vividly remembers the lecture at which her husband outlined his ideas about black holes to a gathering of physicists at the Rutherford Appleton Laboratory in Oxfordshire.
Hunched in his chair, and in a faint whispering speech, Hawking described his heretical idea: black holes are not really ‘black’. Eventually his lecture came to an end. “Silence reigned,” says Jane. “Then the chairman, Professor John G. Taylor of King’s College, London … sprang to his feet, blustering ‘This is quite preposterous. I have no alternative but to bring this session to an immediate close.’” Outside the meeting hall, scientists gathered in shocked huddles to discuss what they had just heard. Hawking was unrepentant. “There is nothing like the eureka moment of discovering something that no one knew before,” Hawking says with typical impish humour. “I won’t compare it to sex, but it lasts longer.”
Hawking later elaborated on his idea of black hole radiation in a paper which he submitted to the prestigious journal Nature. This was at first rejected, but later accepted, and eventually published after minor changes by Hawking. Slowly the idea — that black holes can emit radiation — became mainstream and is now is widely accepted by cosmologists. Indeed such energy is known simply as Hawking radiation. The theory — rated his most enduring and important scientific legacy — was a particular triumph for Hawking because it marked his first notable achievement in his attempts to unify physics, in this case by using black holes, to reconcile the large-scale structure of the cosmos with the small structure of the atom. His work on black holes also paved the way for Hawking to be elected a fellow of the Royal Society in 1974.
Three years later, Hawking was appointed Cambridge’s Lucasian Professor of Mathematics, a post held by Isaac Newton three centuries earlier. By this time, the cosmologist was finding it difficult even to speak. “I wrote scientific papers by dictating to a secretary and I gave seminars through an interpreter, who repeated my words more clearly,” recalls Hawking. In fact, only a few people outside his immediate family could understand what he was saying and his children — Lucy, Robert and Timothy — often had to act as interpreters as well.
Most of the burden of caring for Hawking had by now fallen on Jane’s shoulders, a point stressed by Lucy Hawking. “After getting the children ready for school, she would lift my father out of bed and into his chair. She would then wash him, feed him and get him off to work.”
It is a crucial point. Hawking has achieved wonders while suffering immense disability but this has only been managed through great sacrifices by others. “My father has maintained a resolute disbelief in his own disability, or rather an inability to accept there is anything he cannot do,” adds Lucy. “This attitude is both admirable and infuriating. When faced with a long flight of stairs to see a view, reliably said to be not very exciting, his insistence on being lifted to the top anyway, drives strong men to tears. This resolve is undoubtedly what sustains him.”
In 1988, Hawking produced his first serious attempt at science popularisation: A Brief History of Time. The book, although aimed at the public, proved fairly hard to follow, with its forays into topics such as imaginary time and 11-dimensional space. Nevertheless, it became an international bestseller and has since sold more then 25 million copies, greatly boosting Hawking’s otherwise meagre coffers.
The book, apart from its astonishing popularity, is also famous for its cryptic last sentence. Having unified the theories of gravity and quantum mechanics, mankind will then surely know “the mind of God,” wrote Hawking. The phrase spawned a plethora of other cosmology books with ‘mind of God’ in the title and also triggered intense speculation that Hawking — an avowed atheist — had found religion in later life. Only recently has the scientist explained his real meaning. “What I meant when I said we would know the mind of God was that if we discovered the complete set of laws, and understood why the universe existed, we would be in the position of God,” he says. So no, Hawking has not succumbed to the blandishments of religion.
In 1985, Hawking contracted pneumonia, a life-threatening illness for a man in his condition. His severe breathing problems led to a tracheotomy that destroyed his remaining powers of speech. Fortunately, a technological fix was at hand. A computerised voice synthesiser was fitted to Hawking’s wheelchair, allowing him to generate words and sentences, albeit at the relatively staid pace of 15 words per minute. Nevertheless, the device prevented Hawking from being totally cut off from communicating with humanity.
By this time, Hawking had lived three decades longer than doctors had expected, though he was still capable of delivering shocks. In 1990, he announced he was divorcing Jane, who had cared for him for more than 25 years, and would instead be living with his nurse Elaine Mason. Elaine and Hawking were eventually married, the union triggering angry responses from his family. Jane bitterly denounced him as an “all-powerful despot” who used people for his own ends while his daughter Lucy likened his attitude to his family to “the Monopoly hotel near their little houses”. Hawking’s second marriage only last a few years, however. He and Mason recently launched divorce proceedings and no longer live together.
By the 1990s Hawking had become an international institution, trundling round the world’s lecture circuit in his electronic chariot with his weary, lolling head and robot-like voice synthesizer. Like him or not, he has come to personify the idea of a pure, disembodied intellect, a man who can range the universe in his mind, the world’s cleverest human trapped in a wasted body.
For his part, Hawking has relished the limelight. He has appeared with actors playing Einstein and Newton in Star Trek: The Next Generation and also as a character in The Simpsons. “Your theory of a doughnut-shaped universe is interesting, Homer,” he announces. “I may have to steal it.” (Today, he still has a Lisa Simpson key ring dangling from his computer while a notice beside it announces: “Yes, I AM the master of the centre of the universe.”)
Certainly, the man’s self-confidence seems unbreachable, and despite his disabilities he can command a meeting with ease, as was recently demonstrated when Hawking spoke to researchers at CERN, Europe’s massive particle physics laboratory near Geneva. The centre’s main lecture theatre was crammed with physicists, mathematicians and cosmologists eager to hear Hawking’s latest thinking on the structure of the universe, and about his attempts to combine general relativity and quantum mechanics. He did not disappoint.
As Hawking told his audience, a major problem for modern cosmology is the fundamental question of what existed before the Big Bang. “However, I have found that if you combine general relativity with quantum mechanics you find that time behaves like another dimension. You can think of the Universe being like the south pole of the Earth with degrees of latitude playing the role of time. The Universe would therefore begin at the south pole and as time passed — the equivalent of moving north round the globe — the Universe would expand. Thus to ask what happened before the beginning of the Universe would be like asking what is south of the south pole. It would be meaningless.”
Hawking envisages the creation of the Universe as being like the formation of steam bubbles in boiling water. Smaller bubbles collapse on themselves, he suggests, in the same way as microscopic universes — before they have time to generate matter or stars or living beings. Larger bubbles would expand rapidly, however, and in our case the corresponding universes would provide the perfect physical conditions for galaxies and humans to evolve. “We are the product of quantum fluctuations in the early Universe,” he says.
In fact, the CERN lecture theatre was a particularly fitting venue for Hawking because the centre’s huge particle accelerator — the Large Hadron Collider (LHC), whose construction will be completed next year — now offers science its best chance to prove some of Hawking’s theories. In a few months, the huge collider will hurl sub-atomic particles into each other at colossal energies and release vast amounts of even smaller particles.
“We still don’t really know what will be produced by the LHC,” says CERN spokesman James Gillies. “However, there is a real chance that it will generate thousands of microscopic black holes which would then decay, releasing Hawking radiation. That will give scientists their first chance to study Hawking radiation directly and would provide perfect proof that his ideas are right. Hawking would be a very strong candidate for a Nobel prize, as well.”
Such an award would be a fitting tribute for a scientist who has laboured under unimaginably trying circumstances in order to shed light on the universe’s origins. It would also be warmly welcomed by his family, with whom Hawking has recently been reconciled. (Jane Hawking’s new book is essentially a reworking of her first biography of Stephen, Music to Move the Stars, with the earlier tome’s bitter insults being replaced by more solicitous prose. It remains to be seen if this helps it sell more copies.)
As to his more recent work, Hawking’s output — like so many other theoreticians in their later careers — has diminished in quality. “The one thing he will be remembered for — among physicists — is Hawking radiation,” says physicist Peter Coles, of Nottingham University. “No one has yet observed it but there is hardly a scientist who would bet that Hawking was wrong. And after that, he did some great work on the thermodynamics of black holes. But there has not been much that is new or exciting for 20 years now.”
Hawking’s most recent work has been concerned with the ‘Information Paradox’. When a black hole explodes, can you tell —from the radiation given off — what originally poured into that black hole? Until recently, Hawking said the answer was no information comes out of an exploding black hole. But then Hawking changed his mind, writing a paper that suggested information could be obtained from such an explosion.
Unfortunately, the paper was heralded, not through publication in a peer-reviewed journal, but by a press release passed around before a lecture. On its own this irritated scientists. Even worse, some now think the paper is flawed. The jury is still out.
In any case, we should not run away with the idea that Hawking is one of the world’s greatest physicists. Hawking makes no such claim himself and neither do his counterparts. In a survey in the journal Physics World a few years ago, the world’s top physicists were asked to name the greatest practitioner of their profession. Albert Einstein came first with 119 votes. Isaac Newton followed with 46, and Ernest Rutherford, who unravelled the structure of the atom, just made the top 10, with 20 votes. And Stephen Hawking? He came last, along with several other scientific also-rans who each garnered a single vote.
“Hawking is so distinctive, trapped in his wheelchair with his strange voice, that he has become the world’s most famous physicist since Einstein,” adds Coles. “But there are dozens of other physicists – including Bohr, Planck, Schrödinger, Feynman, Dirac, and Weinberg – who have had a far greater impact in changing our view of the universe but who remain unknown to the public.”
There’s no question Hawking is a tremendously talented scientist, whose achievements are all the more impressive in light of his physical disability. However, perhaps his greatest contribution to science is not his work on black holes or theories on quantum gravity, but his ability to engage with the public, and share with them that spark of delight felt by all those who marvel at the wonders and mysteries of the universe.
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