Anti gravité:


Voici quelques échos par la presse suivant la tenue du Breakthrough Propulsion Physics Workshop, un premier aperçu des travaux futurs de la NASA dans ses projets DeltaG / BPPW de recherches sur l'antigravitation et les technologies du voyage spatial futur.

NASA Electromagnetic Research Team

Gravity of the situation: Above, while firmly attached to Earth, NASA scientists at the Marshall Space Flight Center in Alabama experiment with gravity shielding-known in common terms as anti-gravity. From left are Tony Robertson, Neil Tyson, Whitt Brantley David Noever, Jerald Oakly, Ronald Koczor and Ning Li, the theoretical physicist behind the work.


By Ulysses Torassa, Plain Dealer Reporter
The Plain Dealer, Cleveland, OH
(© The Plain Dealer 1997).

More than 80 physicists and government researchers will be in Cleveland this week to try to figure out if it really might be possible to travel through the universe using warp drives, wormholes and the massive amounts of energy some scientists believe are stored in empty space.

The topics are straight out of science fiction, but organizers of the Breakthrough Propulsion Physics workshop say they all have a basis in emerging areas of physics that involve faster-than-light travel, the properties of space and time, and the bizarre rules of quantum mechanics that govern the subatomic world.

These seemingly far-out concepts are gaining more attention even among some mainstream physicists and are beginning to be examined for their potential practical value. Now NASA is spending $50,000 to sponsor the workshop here to see if any of these ideas might one day yield a way of traveling outside our solar system to stars and planets light-years away.

"Originally these concepts were considered too far from fruition to warrant spending any time on," said Marc G. Millis, a NASA Lewis Research Center engineer who is organizing the event. "But now they're in the peer-reviewed literature, so now it's `Let's at least take a look at this.'

Still, there are plenty of skeptics, including at least one workshop presenter who seriously doubts anything on the agenda will lead to propulsion breakthroughs.

"They fall into one of two categories: impossible in principle or impossible in practice," said Lawrence M. Krauss, chairman of the physics department at Case Western Reserve University, who is speaking on propellentless propulsion.

As the author of "The Physics of Star Trek," Krauss has delved into many of these topics, searching for evidence that warp drives traveling at the speed of light or travel via wormholes (theoretical tunnels in the fabric of space-time) might actually work. Sadly, he said, he found they really couldn't.

"Some of the ideas that are going to be discussed already violate known laws of physics," he said. "Some that don't, like warp drive, might be possible in principle, but have recently been shown to require 10 billion times the amount of energy in the entire universe."

Among the ideas on the table this week are new theories about gravity and inertia to see if those forces could be manipulated to create propulsion for space flight. Participants also will discuss what might be done with the energy that quantum theory predicts is left even in the emptiest of vacuums. Some calculations have suggested that there is enough potential energy in a coffee cup's worth of empty space to boil away all the Earth's oceans, Millis said.

If we are to reach stars and planets outside our solar system, it will require radical new methods for propelling spacecraft. With current space rockets, a trip to the nearest star beyond the sun would use up many times more fuel than the entire weight of the known universe, Millis said. Even then, the journey would take about 1,000 years.

So NASA is very keen on figuring out better ways to get through space quickly and cheaply. The agency has studied concepts like nuclear-powered rockets, and "sails" that would be pushed along by light or magnetism. But many technological hurdles remain.

Millis' group represents the farthest reaches of those efforts. And the tiny budget - NASA is expected to spend only a few hundred thousand dollars on the first projects - shows that the group is far from the mainstream of the agency's thinking and planning.

Millis is the first to acknowledge that many of the ideas at the workshop are based on theories that are not widely accepted, and some involve trying to do things - like travel faster than the speed of light - that many physicists flatly consider impossible.

At this point they can't even envision what a spacecraft based on any of these ideas might look like.

"There's inspiration and then there's vision," Millis said. "With vision, you know the laws of nature and you can begin engineering ideas. You may not have figured out exactly how to make it happen. On this subject we can't do the visions yet. We don't have the science to contemplate how big these things might be, what shape. This aims to point the science to answer these questions for propulsion issues."

Still, he said, if even one of the ideas proves useful for spaceflight, the gains would be enormous. "The benefit to humanity is almost immeasurable," he said.

While these are ideas that have long been a staple of Star Trek episodes and sci-fi novels, more physicists are taking them seriously, said Robert L. Forward, an aerospace scientist who will talk about physical evidence that vacuum energy exists, as well as his ideas about negative matter during the workshop.

"You do not need to go to the UFO literature and science fiction to find new ideas. All you need to do is read the abstracts from the papers in Physical Review {an academic physics journal}," Forward said. "In one recent issue, there were four papers on time machines."

Forward, himself a science fiction writer as well as a scientist, acknowledged that these were the kinds of ideas whose practical use can seem dauntingly distant. "These papers in Physical Review that are talking about how to build wormholes, they start out with things like, `Take a galaxy and do this and that.' So it's not something we can do with known technology,' he said.

The field does attract a lot of people on the fringes of science, which is why Millis asked that the exact location for the invitation-only workshop not be publicized. He routinely hears from what he calls maverick inventors who are certain they have stumbled on a way to create thrust without rockets. Usually they are fooled by Earth-bound effects, he said.

"The program attracts some people who are overly enthusiastic sometimes," Millis said. "I need to focus on people I know will be constructive."

Their goal, he said, isn't to come up with hard answers during the workshop, but to try to focus on a few ideas that can be easily and inexpensively tested to see if they hold any hope of panning out.

NASA Electromagnetic Antigravific Disk

A close-up of the high-temperature superconducting disk that produces the gravity shielding effect.



By Keay Davidson Examiner Science Writer
San Francisco Examiner
Page A-1
(© 1997 San Fransisco Examiner)

In a development straight out of "Star Trek," NASA is looking seriously at the feasibility of flight to the stars.

Way-out schemes for traveling to the nearest stars are being assessed by scientists and engineers as part of a low-profile, micro-budget NASA program, dubbed Breakthrough Propulsion Physics.

Wormholes, warp drives and other means for interstellar flight - long staples of science fiction - may become science fact, if the researchers get their way.

Tuesday through Thursday, more than 80 employees of the space agency and space-related industries will gather at NASA's Lewis Research Center in Cleveland to hear 14 scientists and engineers discuss ways to achieve interstellar flight.

Possibilities include the generation of so-called wormholes, something akin to rips in the fabric of space and time. Some physicists have speculated that a spaceship passing through a rip might emerge in a distant part of the cosmos.

"We don't even know if these things are physically possible," said the program's chief and sole full-time employee, aerospace engineer Marc Millis of NASA-Lewis.

But, Millis added hopefully: "Progress is not made by conceding defeat."

Why go to the stars? Among other things, to find habitable planets for humanity, Millis said.

"Imagine if we could give citizens access to a whole nother planet Earth," said Millis, 37. "Imagine if there were an uninhabited planet suitable enough to live on."

The main barrier to interstellar flight remains Albert Einstein's theory of relativity, which forbids travel at speeds faster than light - 186,000 miles per second. The nearest stars, other than the sun, are four light-years away. A light-year is 6 trillion miles, the distance that light travels in a year. Because of the Einsteinian limit, a spaceship would need at least four years to reach the closest stars, Proxima Centauri and Alpha Centauri.

Two scheduled speakers come from the Bay Area - Raymond Chiao of the UC-Berkeley physics department and astrophysicist Bernhard Haisch of Lockheed Missiles & Space Co.'s office in Palo Alto.

Haisch is expected to discuss the possibility of space propulsion using something called "the momentum of the quantum vacuum." Chiao plans to discuss how laboratory experiments suggest that under certain circumstances, photons - particles of light - appear to travel "at an effective speed of 1.7 times the speed of light."

The program has official liaisons at a number of NASA centers around the nation - for example, Larry Lemke at NASA's Ames Research Center in Mountain View.

The proposed technologies "are extremely long shots," cautions one enthusiast, John Cole. He is manager of space transportation research at NASA's Marshall Space Flight Center in Alabama, which funds the program at Lewis.

"Theories of this type have cropped up perpetually from time to time," Cole said, "and usually wind up not leading anywhere. . . . But if we don't look, we certainly will never find anything."

And the time may be right.

"People, particularly young people, are sort of rejecting the claustrophobic position that we are locked in this solar system without any chance at all of going to others," said Whitt Brantley, chief of the advanced concepts office at NASA's Marshall Space Flight Center in Alabama.

But not everyone at NASA is pleased by talk about star ships.

Within the space agency, "the reactions completely cover the entire spectrum," Cole said. "There are those that believe we are about to get NASA embarrassed with some ideas that can't possibly be achieved.

"And there are others that are just delighted that NASA is finally open-minded enough, and (has) enough courage - and encouragement from the administrator (Daniel Goldin) - to pursue these things," Cole added.

Brantley interjected: "If you look back in history before great discoveries were made, there were great minds trying to show they were impossible."

How did an agency packed with conservative engineers get interested in interstellar flight?

For one thing, NASA Administrator Goldin made the once-taboo topic acceptable by publicly speculating about it.

Also, recent research published "in credible, peer-reviewed (scientific) literature" has made interstellar flight seem more feasible than it did decades ago, Millis said.

For example, the warp drive plan is based on an idea proposed by Miguel Alcubierre, an astrophysicist from the University of Wales. He published the method in 1994 in a little-known scientific journal called "Classical and Quantum Gravity."

According to one theory of warp drive, one could get around Einstein's speed limit for matter by moving the space around the matter. The space, being non-material, could exceed the speed of light - or so the theory implies.

Larry Diehl, director of NASA-Lewis' research and technology directorate, acknowledged with a chuckle that on the Internet, there has been chatter about whether "we are looking to violate the laws of physics. The answer, of course, is "no."

"We haven't made any large-scale commitment to funding work in this area. (Still) if we don't continue to reach out and explore, I don't feel that we make progress," said Diehl, an aerospace engineer who has worked for the agency for three decades.

The program's current one-year budget is $50,000 - pennies by NASA's usual gold-plated standards.

NASA has published the agenda for its conference on the World Wide Web at



By Seth Borenstein of The Sentinel Staff
Orlando Sentinel
Page A1
(© 1997 Orlando Sentinel)

Warp drive. Anti-matter. Worm holes. Time travel. Reducing gravity. Getting power from thin air. They all seem the stuff of Star Trek, Contact and other science-fiction movies.

They also are real - if remote - scientific possibilities that the federal government is studying.

"I hate to use the term, but it's government-sponsored science fiction," said Robert Frisbee, leader of the Advanced Propulsion Technology Group at NASA's Jet Propulsion Lab. "We're trying to make science fiction into science fact."

The field is called breakthrough propulsion physics, and NASA, the Air Force and others really are researching ways to zip through space some 50 years from now.

This science is growing. A group of 100 experts in the field will gather Tuesday in Cleveland for its first workshop and brainstorming session.

Next month researchers at NASA's Marshall Space Flight Center in Alabama will try an experiment to reduce gravity.

The ultimate goal is to reach another solar system or galaxy. Modern rocketry isn't enough.

"If we want to get to these places, if we want to do what Star Trek shows, you have to have whatever the future equivalent of warp drive is," said John Anderson, NASA's advanced concept executive whose job is to encourage scientists to think about the distant future.

And there's plenty to think about.

Marc Millis, leader of NASA's breakthrough propulsion physics program, rattled off several nonrocket-oriented ways to get out of this neck of the galaxy:

    Vacuum fluctuation. According to the theory there's a gigantic amount of energy in literally nothing, energy leftover when you take away all other energy sources. It's what makes bubbles form and clouds clump. There's enough energy in a cup supposedly to boil off an ocean.

    Warp drive. That's going faster than the speed of light by manipulating the fabric of space and time. Millis, borrowing liberally from Star Trek, has even created a 16-inch model star cruiser with warp engines.

    Reducing an object's gravity. An experiment in Finland seemed to produce this effect. Marshall scientists hope to reduce an object's gravity by 1 percent next month by using twin spinning superconductors in a magnetic field. Eventually lots of these could conceivably nearly levitate a rocket off the ground, researchers say.

    Powering ships by anti-matter. Using electromagnetic tracks, scientists have been able to produce anti-protons. These are parts of atoms that have had their electrical charges reversed. Anti-matter can be a catalyst for nuclear reactions.

    Worm holes. These are supposed to be cosmic tunnels that are shortcuts through space and time. Some physicists say theoretically they could exist.

Millis acknowledges that there are huge barriers to each idea. But, he said, barriers can be leaped over.

"The whole idea behind the breakthrough physics thing is to look at all these weird things and find something testable," said Robert L. Forward, a physics consultant to NASA and the Air Force.

If this sounds way too close to science fiction, there's a good reason. Some science fact dreamers also are science fiction plotters. Forward, one of the first proponents of breakthrough propulsion, has written 10 science-fiction novels.

Forward and others say the most recent example of science fiction and science fact mixing is the hit movie Contact.

When the late astronomer Carl Sagan was writing his 1985 science fiction novel Contact, he created a worm hole for his heroine to travel through to meet an alien culture. Sagan sent an idea for a worm hole to physicist Kip Thorne and asked whether it was theoretically feasible.

Sagan's idea wasn't.

But Thorne and his students were intrigued. They came up with an idea that would fit with the theory of relativity, and Sagan adopted it. The physicists kept studying it and published numerous scientific peer-reviewed papers about worm holes and the use of them not just to travel in space, but in time.

Sagan's book spurred an interest in worm holes that is now "a cottage industry in physics," Frisbee said.

Science often has followed science fiction, Frisbee said. Modern rocketry, communication satellites and other technologies all first appeared in science fiction.

Richard Berendzen, an American University astronomer who is not part of the breakthrough physics crowd, said "science-fiction writers, particularly the really good ones, the Arthur C. Clarkes, have sometimes guessed or have been wise enough to predict what's going down on the road."

Now for a reality check.

Bob Park, a University of Maryland professor and spokesman for the American Physical Society, a U.S. group of physicists, calls the research a waste of time, effort and money.

"It's not the money so much as sort of the credibility to a whole range of goofy ideas," Park said. "There's sort of a free-energy cult that has developed around the world. There's a lot of scams going around the world right now. People are selling stock in companies that claim to be producing energy from nothing."

But Millis said his group is just looking to see whether there's affordable research into these ideas because "the potential gains are enormous."

Millis, the only NASA employee working fulltime on breakthrough physics, says the space agency is spending $40,000 a year on research and is contemplating boosting that to $500,000 a year. By comparison, a space shuttle uses about $500,000 worth of fuel each time it launches.

John Cole, project manager for space transportation research at Marshall, said: "If we could find some new physics it sure would be helpful. We don't know what they are. But we won't find them if we don't look."

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