http://www.space.com/businesstechnology/060215_technovel_antigravity.html

"An 'antigravity' propulsion system was proposed at the Space Technology and Applications International Forum (STAIF) in Albuquerque on Febuary 14 by Dr. Franklin Felber. His new exact solution to Einstein's gravitational field equation gives hope to space enthusiasts that it might be possible to accelerate space craft to speeds approaching that of light without crushing the contents of the craft."

"Dr. Felber's paper states that a 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. This "beam" intensifies as the speed of the mass approaches that of light.

The paper shows how to use the repulsion of a body speeding through space to accelerate large spacecraft quickly while reducing internal tidal forces that could tear the cargo apart. The paper argues that the payload would "fall weightlessly" in an antigravity beam as it is accelerated to a substantial fraction of light speed."

Interesting, if it checks out. Finding exact solutions to the gravitational field equations is *really hard*, so it's not easy to say offhand if this makes sense or not.

Just off the top of my head, it seems the only option we have for accelerating things to near-lightspeed velocities are various particle accelerators. The question is, is the effect big enough to be measurable from such tiny masses?

So you get propelled by some planetbound device... how do you break once you reach your destination?

You simply *reverse the polarity*!

So here's the deal: we make some device on earth, and then use it to accellerate it away into space. Then after millions of kilometers you decide to switch polarity. but will you still be in the beam of the device? the further you get away, the more exact needs to be your aiming. It's one thing to aim a telescope somewhere, but could you do it in this case?

I was *joking*. :)

The correct answer is that deceleration will have to be performed by the ship's reverse thrusters. Yes, it will take a long time.

But now that I think of it, the first flight could set a base on the other side with an antigravity net based on the same principle, slowing the ship down. Then the next flights would be way faster.

what would be the effect if a small car was higher than a big car.how does grvity interrupt whith cars and Earth?

*gravit

Compared to the mass of Earth, the influence of a car's mass, even a big one, is insignificant.

why is it insignificant?

Insignificant means "having no weight or effect".

For example, when a rocket lifts off, how much is the planet going backwards?

>>11

Because the numbers we're working with are on the order of millions and billions. The mass of a car is on the order of about a thousand, so it contributes almost nothing.

>>8 to answer your question, could you be more specific? Especially about the 'effect' (by what)

Of course the problem that this "solves" is just mitigated - you still have to get the *other* large body up to that "very high speed" for this to work!

No such thing as a free lunch, folks.

http://www.esa.int/SPECIALS/GSP/SEM0L6OVGJE_0.html**Gravitomagnetic London Moment**

News - 23 March 2006

"Scientists funded by the European Space Agency have measured the gravitational equivalent of a magnetic field for the first time in a laboratory.

Under certain special conditions the effect is much larger than expected from general relativity and could help physicists to make a significant step towards the long-sought-after quantum theory of gravity."

"Their experiment involves a ring of superconducting material rotating up to 6 500 times a minute."

"Spinning superconductors produce a weak magnetic field, the so-called London moment.

The new experiment tests a conjecture by Tajmar and de Matos that explains the difference between high-precision mass measurements of Cooper-pairs (the current carriers in superconductors) and their prediction via quantum theory. They have discovered that this anomaly could be explained by the appearance of a gravitomagnetic field in the spinning superconductor (This effect has been named the Gravitomagnetic London Moment by analogy with its magnetic counterpart)."