|Photo by Markus Schreiber/AP|
STEPHEN Hawkings voice drifts through the air, eerily familiar. These are the synthesized vocal cords that attempted to explain to Homer Simpson the nature of space and time, that joshed on the Star Trek holodeck with Newton and Einstein. Along with the latters shock of hair, Hawkings computerized tones have come to symbolize the ideal of Genius writ large. Yet the source of these sounds seems impossibly small and fragile in the flesh. Bunched in his wheelchair at the front of the room, Hawking is a man in miniature, his doll-like body in hapless contrast to the gargantuan brain it supports.
At the worlds first string cosmology conference, held recently at UC Santa Barbara, Hawking was expounding on his latest ideas about the creation of the universe. Its a subject he famously catapulted to the center stage of physics with his proof that space and time must have begun with a singularity, a cosmic-scale version of a black hole. That work was the subject of his Ph.D. thesis, and it built upon Einsteins theory of relativity to demonstrate that any viable universe had to have been born from a single, infinitely intense point a kind of cosmological seed. Hawking had come to Santa Barbara to revise himself, presenting to an audience of fellow physicists a new model of cosmic genesis which, as he explained, describes a universe that expands, contracts, bounces and expands again.
Up close Hawking looks like an imp, an escapee from Lord of the Rings. His delicate features are preternaturally enhanced by four decades of living with Lou Gehrigs disease. Since I first interviewed him 18 years ago, he has visibly shrunk, but at this point it is a medical miracle he is alive at all. Its his eyes that demand your attention, as if the life force withdrawn from his body has concentrated in his orbs. They dont just twinkle, they radiate light. Though he can barely move anymore and must now be attended by a small army of nurses, when he nods assent to a question, one senses the power of a still-extraordinary mind at work. This combination of gymnastic intelligence and immobile body creates a profound sense of otherness Hawking is as close to an alien among us as Mr. Spock, and every bit as enigmatic.
While he still believes in an original beginning, Hawking suggests that since this cosmic birth our universe might have had many lives. Think of a balloon thats inflated, deflated, then inflated again. According to his new model, our particular space and time will eventually end, but the universal whole will continue, carrying into its next life a residue of its past repetitions.
The impetus for Hawkings revision is the revolution that has electrified the world of theoretical physics: string theory. Using the mathematical putty of this theory, physicists are playing gods, bringing forth from the pluripotent sea of their equations an explosion of universes. At UCSB, string theorists served up visions that contained not just one universe but multiple, expanding and infinitely extending arrays of universes. There were pocket universes, toy universes and baby universes budding like spores off parent universes a dizzying plethora of possibility in which almost any world that might be imagined was deemed to be happening somewhere.
To its proponents string theory holds out the hope that this may be the longed-for theory of everything. To others, it seems a theory of nothing. It is not even science, they argue. For as its greatest exponents acknowledge, there is not a shred of evidence to support any of its conclusions so far. Speaking on Nova the other night, Nobel Prizewinning particle physicist Sheldon Glashow expressed his feelings in scathing terms. Let me put it bluntly, he said, there are physicists and there are string theorists. For Glashow, physics is about experiment, and without experimental verification string theory has no validity. Not since the Middle Ages has speculation so exceeded the reach of observation. Is this a theory of physics, Glashow asked, or philosophy?
WHATEVER string theorys epistemological status, its hot. Glashow was part of a Nova string theory special, PBSs most expensive science project ever, a $3.5 million, three-part epic titled The Elegant Universe. The series is based on the 1999 best-selling book of the same name by Columbia University physicist Brian Greene, and PBS honchos are clearly hoping it will be the next Cosmos, with Greene the next Carl Sagan. If string theory is right, Greene enthused giddily at the start of the show, we may be living in a universe where reality meets science fiction.
Certainly the producers seemed determined to distract us with all the techniques of sci-fi cinema there were more things flying at the screen than in a Star Wars battle. Like Luke Skywalker, Greene seemed to be continually dodging projectiles. He took the task in stride, for he had evidently been schooled in The Crocodile Hunter style of presentation. I half expected him to wrestle one especially annoying graphic to the ground. Things whirled and whizzed and flashed; lights pulsed, objects popped in and out of existence.