Recently in Space Propulsion Category

Wow, we are living in surreal times. Just in the last month we have now seen two quantum leaps in space propulsion. The first was a proposal for a hyperspace ship, and now an inertialess drive. Is this still 2006, or did somehow we jump ahead 50 years? Bizarre and simply amazing.

From Physical Review:

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Felber's antigravity discovery solves the two greatest engineering challenges to space travel near the speed of light: identifying an energy source capable of producing the acceleration; and limiting stresses on humans and equipment during rapid acceleration.

"Dr. Felber's research will revolutionize space flight mechanics by offering an entirely new way to send spacecraft into flight," said Dr. Eric Davis, Institute for Advanced Studies at Austin and STAIF peer reviewer of Felber's work. "His rigorously tested and truly unique thinking has taken us a huge step forward in making near-speed-of-light space travel safe, possible, and much less costly."

The field equation of Einstein's General Theory of Relativity has never before been solved to calculate the gravitational field of a mass moving close to the speed of light. Felber's research shows that any mass moving faster than 57.7 percent of the speed of light will gravitationally repel other masses lying within a narrow 'antigravity beam' in front of it. The closer a mass gets to the speed of light, the stronger its 'antigravity beam' becomes.

Felber's calculations show how to use the repulsion of a body speeding through space to provide the enormous energy needed to accelerate massive payloads quickly with negligible stress. The new solution of Einstein's field equation shows that the payload would 'fall weightlessly' in an antigravity beam even as it was accelerated close to the speed of light.

Accelerating a 1-ton payload to 90 percent of the speed of light requires an energy of at least 30 billion tons of TNT. In the 'antigravity beam' of a speeding star, a payload would draw its energy from the antigravity force of the much more massive star. In effect, the payload would be hitching a ride on a star.

"Based on this research, I expect a mission to accelerate a massive payload to a 'good fraction of light speed' will be launched before the end of this century," said Dr. Felber. "These antigravity solutions of Einstein's theory can change our view of our ability to travel to the far reaches of our universe."

More immediately, Felber's new solution can be used to test Einstein's theory of gravity at low cost in a storage-ring laboratory facility by detecting antigravity in the unexplored regime of near-speed-of-light velocities.

I wouldn't have taken this seriously, but I read it over at Roland Piquepaille's Technology Trends

According to the Heim quantum theory (HQT) developed in the 1950s, it should be possible to build an 'hyperspace' engine allowing a spacecraft to reach Mars in 3 hours. It would also allow us to travel to stars more that 10 light years away in 80 days by slipping into a different dimension. But is interstellar space travel a dream or a future reality? It all depends if this controversial theory about the fabric of our universe is correct or not. So far, it seems that a majority of physicists thinks that this theory is either incomplete or almost understandable. Nevertheless, some scientists working for the U.S. Department of Energy think that such an 'hyperspace' engine could be tested within five years.

An extraordinary "hyperspace" engine that could make interstellar space travel a reality by flying into other dimensions is being investigated by the United States government.

The hypothetical device, which has been outlined in principle but is based on a controversial theory about the fabric of the universe, could potentially allow a spacecraft to travel to Mars in three hours and journey to a star 11 light years away in just 80 days, according to a report in today's New Scientist magazine.

The theoretical engine works by creating an intense magnetic field that, according to ideas first developed by the late scientist Burkhard Heim in the 1950s, would produce a gravitational field and result in thrust for a spacecraft.

Also, if a large enough magnetic field was created, the craft would slip into a different dimension, where the speed of light is faster, allowing incredible speeds to be reached. Switching off the magnetic field would result in the engine reappearing in our current dimension.

The US air force has expressed an interest in the idea and scientists working for the American Department of Energy -- which has a device known as the Z Machine that could generate the kind of magnetic fields required to drive the engine -- say they may carry out a test if the theory withstands further scrutiny.

Professor Jochem Hauser, one of the scientists who put forward the idea, told The Scotsman that if everything went well a working engine could be tested in about five years.

However, Prof. Hauser, a physicist at the Applied Sciences University in Salzgitter, Germany, and a former chief of aerodynamics at the European Space Agency, cautioned that any prototype would be based on a highly controversial theory that would require a significant change in the current understanding of the laws of physics.

"It would be amazing. I have been working on propulsion systems for quite a while and it would be the most amazing thing. The benefits would be almost unlimited," he said.

"But this thing is not around the corner. We first have to prove the basic science is correct and there are quite a few physicists who have a different opinion. It's our job to prove we are right and we are working on that."

He said the engine would enable spaceships to travel to different solar systems. "If the theory is correct then this is not science fiction, it is science fact," Prof. Hauser said.

"NASA have contacted me and next week I'm going to see someone from the [U.S.] air force to talk about it further, but it is at a very early stage. I think the best-case scenario would be within the next five years [to build a test device] if the technology works."

The U.S. authorities' attention was attracted after Prof. Hauser and an Austrian colleague, Walter Droscher, wrote a paper called "Guidelines for a space propulsion device based on Heim's quantum theory."

From SpaceTime Hypersurfing by Michael Szpir,

In some future history, 1994 may be remembered as the year that the warp drive was first conceived to be a physical possibility. Long a cliche' of science- fiction writing, the warp drive has transported countless fictional characters through light-years of interstellar space in the time it takes for you or me to travel to the market. Unfortunately for real-world travelers, the warp drive has always been thought to be inconsistent with the laws of physics.

But all this has changed. In the May 1994 issue of Classical and Quantum Gravity, Miguel Alcubierre, a physicist at the University of Wales describes a space-travel scenario that bears an uncanny resemblance to the warp drive of science fiction. With Alcubierre's warp drive, we could reach any place in the universe in as short a time as we please!

Excerpt from Miguel Alcubierre's original paper
Class. Quantum Grav. 11 (1994), L73-L77.

It is shown how, within the framework of general relativity and without the introduction of wormholes, it is possible to modify a spacetime in a way that allows a spaceship to travel with an arbitrarily large speed. By a purely local expansion of spacetime behind the spaceship and an opposite contraction in front of it, motion faster than the speed of light as seen by observers outside the disturbed region is possible. The resulting distortion is reminiscent of the "warp drive'' of science fiction. However, just as it happens with wormholes, exotic matter will be needed in order to generate a distortion of spacetime like the one discussed here.

More recent work suggest that this warp drive could be created without exotic matter in Hyper-fast travel without negative energy.

And another paper by Hal Puthoff discussing the possibility of using Zero-point energy fluctuations to do the same thing.

What's interesting about this is that Miguel Alcubierre came up with this idea in his spare time! So ask yourself this, if one humble guy can figure this out on his time off, what do you think minds thousands or millions of times more intelligent will think up and implement?