Ted S. Warren / AP
British physicist Stephen Hawking discusses how binary pulsars could produce evidence for the existence of extra dimensions, during a Seattle Science Festival symposium on Saturday.
British physicist Stephen Hawking has lived longer and achieved more than most quadriplegics have, but he's not done yet: The 70-year-old theoretician is still waiting for experimental evidence to launch him toward a Nobel Prize.
Hawking used his Nobel aspirations as a punch line more than once during his Saturday-night talk at Seattle's Paramount Theater, during a Seattle Science Festival symposium that also featured systems biology pioneer Leroy Hood and paleontologist Jack Horner. The "Luminaries Series" presentation also featured evolutionary rap and modern dance, but Hawking was clearly the headliner.
Part of Hawking's appeal is that he just keeps going, and going, and going, despite his disability. He's lived for decades with a progressively paralyzing form of amyotrophic lateral sclerosis, or ALS. His entourage includes a nurse practitioner and an aide who looks after the high-tech system that translates his cheek twitches into speech. (He and his team have been testing a more advanced system that can turn brain-wave patterns into words.)
All this work to overcome adversity wouldn't have taken Hawking so far, however, if it weren't for his crazy smarts and his sharp wit. Both were in evidence during Saturday's talk, titled "Brane New World." Hawking laid out his perspective on what he thinks could be the ultimate theory of the universe, known as M-theory.
"We have been searching for the Theory of Everything for the past 30 years, and now we think that we have found a candidate," he said.
M-theory is a "mother" theory that fuses together several strains of string theory, and allows for dimensions of space beyond the three we're familiar with. For a long time, Hawking was reluctant to accept the idea of unseen extra dimensions, but on Saturday he said everything else about M-theory made so much sense that he couldn't resist.
Ted S. Warren / AP
Stephen Hawking composes his conversations with face movements, aided by a sophisticated sensor and computer system hooked up to his wheelchair.
"I feel to ignore it would be like claiming that God put fossils in the rocks to trick Darwin into believing in evolution," Hawking said.
The big question is, why haven't we detected those darn dimensions? M-theory's proponents suggest that some forms of energy, such as light, are confined to our three-dimensional space (known as a "brane," as in membrane). Gravity, however, just might leak out of our brane?? and that effect could be theoretically be detected.
The key word is "theoretically." Picking up evidence of the extradimensional effect would require high-resolution measurements of high-energy phenomena, such as the clash of binary pulsars in outer space or the smash of subatomic particles at velocities near the speed of light. No such evidence has yet come to light, despite the best efforts of gravitational-wave observatories in the U.S. and elsewhere, as well as the Large Hadron Collider on the French-Swiss border.
If astronomers were ever able to observe the behavior of black holes, that could point to the effect of extra dimensions, Hawking said. One of the biggest achievements of his career was to lay out the theory for how black holes can eventually fizzle out, due to a phenomenon known as Hawking radiation. If black holes emitted part of their energy into extra dimensions, in a form Hawking called "dark radiation," that could explain why astronomers have not yet seen the expected gamma-ray burst from a dying black hole. The alternative would be that low-mass black holes are so rare that virtually none of them have gotten small enough to die out.
"That would be a pity," he said, "because if a low-mass black hole were discovered, I would get a Nobel Prize." At that point, a giant image of the Nobel Prize medallion flashed above the stage.
It might also be possible to detect the leakage of energy into extra dimensions by creating microscopic black holes at the Large Hadron Collider, Hawking said. That phenomenon hasn't yet been observed at the LHC. Before the collider started up, there was a huge flap (and a federal court case) over fears that such micro-black holes, if created, might gobble up the planet. But Hawking said that would never happen.
"Instead, the black hole would disappear in a puff of Hawking radiation ? and I would get a Nobel Prize," he said.
Before his talk, Hawking answered a few questions that were submitted by journalists (including yours truly) in advance. The topics covered some of the physicist's favorite topics, including time travel and the potential threat of an alien invasion. He also referred to his family life, which was a big part of his agenda in Seattle. One of his three children lives in the area, and over the past few days, Hawking and his family took in the King Tut exhibit at the Pacific Science Center, a boat cruise on Elliott Bay and a circus-dinner performance at Teatro Zinzanni. It all made for a great Father's Day visit to the Emerald City.
Here's the Q&A from the pre-talk press conference:
Q: What would it take to make time travel a reality, and how would that affect our present reality?
A:?"We are all traveling forward in time anyway. We can fast-forward by going off in a rocket at high speed, and returning to find everyone on Earth much older or dead. Einstein's general theory of relativity seems to offer the possibility that we could warp space-time so much that we could travel back in time. However, it is likely that the warping would trigger a bolt of radiation that would destroy the spaceship, and maybe the space-time itself.
"I have experimental evidence that [backward] time travel is not possible. I gave a party for time travelers, but I didn't send out the invitation until after the party. I sat there a long time, but no one came."
Ted S. Warren / AP
Physicist and best-selling author Stephen Hawking, right, answers questions from reporters as people waiting for his public appearance look on at left at Seattle's Paramount Theater on Saturday. Hawking was taking part in a Seattle Science Festival symposium focusing on the topic of evolution. Science editor Alan Boyle ... or at least the back of his balding pate ... can be seen in the foreground.
Q:?If M-theory is the only candidate for a complete theory of the universe, what?s the best evidence that you think will be found to support the theory? Lacking that evidence, isn?t M-theory merely another kind of religion?
A:?"M-theory is the only theory that seems to have all the properties that we would expect of a complete and consistent theory of everything, but that may just reflect our lack of imagination. If M-theory is correct, it predicts that every particle should have a superpartner. So far we have not observed any superpartners, but the hope is that they will be found at the LHC. If they are discovered, that will be strong evidence for M-theory. On the other hand, if they are shown not to exist, that will be exciting, because then we'll learn something new."
Q: How would you describe your quality of life? What do you miss most from before the onset of ALS?
A:?"Although I'm severely disabled and on a ventilator, my quality of life is pretty good. I have been very successful in my scientific work, and have become one of the best-known scientists in the world. I have three children, and three grandchildren so far. I travel widely, have been to Antarctica and have met the presidents of Korea, China, India, Ireland, Chile and the United States. I have been down in a submarine, and up in a zero-gravity flight in preparation for the flight into space that I'm hoping to make on Virgin Galactic.?
"Despite my disability, I have managed to do most things I want. My main regret is that it has prevented me from playing with my children and grandchildren as fully as I want."?
Q:?John Gribbin recently argued that we are almost certainly the only intelligent life in the Milky Way ? ?do you think he?s right or wrong, and why? Also, SETI astronomer Seth Shostak argues that even if there are other intelligent civilizations out there, it?s too late for us to keep quiet about our existence, because it?s possible to pick up the signals we?ve sent out over the past 70 years. So isn?t it too late for us to keep quiet, and shouldn?t we be thinking about upgrading our defenses against the alien hordes?
A:?"We think that life developed spontaneously on Earth, so it must be possible for life to develop on suitable planets elsewhere such as the Earth. But we don't know the probability that a planet develops life. If it is very low, we may well be the only intelligent life in the galaxy. Another frightening possibility is, intelligent life is fairly common, but that it destroys itself when it reaches the stage of advanced technology.
"Evidence that intelligent life is rare or short-lived is that we don't seem to have been visited by extraterrestrials.I am discounting claims that UFOs contain aliens. Why would they appear only to cranks and weirdos? Nor do I believe that there is some government conspiracy to conceal the evidence, and keep for themselves the advanced technologies the aliens have. If that were the case, they aren't making much use of it. Further evidence that there isn't any intelligent life within a few hundred light-years comes from the fact that SETI, the search for extraterrestrial intelligence, hasn't picked up their television quiz shows.?
"It is true that we advertise our presence by our broadcasts. But given that we haven't been visited for 4 billion years, it is unlikely that aliens will come anytime soon."?
Updates on the 'Chicken-saurus'
Hawking may have been the headliner, but he wasn't the only luminary at Saturday's "Luminaries Series" symposium on the theme of evolution. Jack Horner, who's based in Bozeman at Montana State University's Museum of the Rockies and has served as an adviser for the "Jurassic Park" movies and the "Terra Nova" TV series, brought the sellout crowd at the Paramount up to date on his quest to create a "Chicken-saurus."
"We're basically going to turn a chicken into a dinosaur," Horner said.
The idea is that the genetic code in chicken cells may still carry the instructions for producing traits that are associated with the dinosaurs from which they descended. "Birds are dinosaurs, so we don't have to 'make' a dinosaur ? we already have them," Horner said. He and his colleagues are looking for ways to express those long-buried traits, known as atavisms. Even humans can express atavisms.?For example, there have been cases of children born with tails.
"You don't have to do any magic," Horner told me. "You just have to find the atavisms in the genes."
Some researchers have already found the genes to produce chicken teeth, and Horner and his colleagues are methodically checking chicken embryos for avenues that could be used to create birds with long, dino-like tails or three-fingered claws like the ones sported by the velociraptors in "Jurassic Park." Horner told me that one of his students compared the effort to the Apollo moonshots.
"It's more than possible," Horner said. "It's just going to take a lot of money."
The future of medicine
In his talk, biologist Leroy Hood outlined his vision of the medical frontier. As the founder of Seattle's Institute for Systems Biology, Hood champions an approach to health care he calls P4?? predictive, preventive, personalized and participatory medicine. He said P4 medicine will arise from the convergence of revolutions in genetic analysis and data processing.
"Ten years in the future, each and every one of you will have your complete genome sequenced," Hood said. If quintillions of bytes' worth of genomic data can be used to nail down the linkages to disease factors as well as the factors that lead to wellness, it should be possible to get health care that's better as well as cheaper.
But getting the payoff from that promise depends on making the genomic data available to researchers, most likely on an anonymized basis, as well as developing the computational firepower to make sense out of a massive cloud of that data. "None of the IT companies have looked at this seriously," Hood said.
To get the ball rolling, Hood said he and his colleagues are talking with four small countries to implement P4 health-care programs in the next two or three years. Although Hood didn't name the countries, his institute already has a partnership with the Grand Duchy of Luxembourg to work on P4 initiatives.
"I have thought about going to small countries because I think the health-care system in the U.S. is too fragmented and disjointed to have any coordinated kind of change, but if you see that another country has done it very well, then that will be quite convincing," he said.
Alan Boyle is msnbc.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the?Cosmic Log page?to your Google+ presence. You can also check out?"The Case for Pluto,"?my book about the controversial dwarf planet and the search for new worlds.
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