Posted on 04/04/2004 1:37:51 PM PDT by Destro
NASA puts new spin on old Einstein
By Richard Macey
April 5, 2004
Almost 90 years after Albert Einstein published his theory that space and time are "curved", it is about to be put to a $US850 million ($A1.1 billion) test.
Next Sunday week, if all goes well, a NASA satellite fitted with four tiny gyroscopes will be fired from Vandenberg Air Force Base, California, into a 640-kilometre- high orbit.
The size of ping-pong balls, the gyroscopes will be set rotating, aligned to a star tracked by the satellite's on-board telescope.
If Einstein's theory of relativity is right, the angle at which they spin should gradually drift over the next two years as the satellite orbits.
According to the theory, gravity does not only distort space up and down, left and right, forward and backward but can also make time run slower, so that the tick of a second on a clock may not always take exactly one second.
But Einstein's theory has only been partially verified.
"Until a theory is thoroughly tested," said Stanford University scientists, who helped develop the mission, "we cannot accept it as fact."
NASA said the satellite "will measure how space and time are warped by the presence of the Earth, and, more profoundly, how the Earth's rotation drags space-time around with it".
"These effects, though small for the Earth, have far-reaching implications for the nature of matter and the structure of the universe," the agency said.
First proposed in the 1950s, the satellite, Gravity Probe B, has been funded by NASA since 1964, its design extensively changed to ensure success.
It is arguably "among the most thoroughly researched programs" that NASA has undertaken.
Warp drive possible
By BBC News Online Science Editor Dr David Whitehouse In Star Trek, the USS Enterprise is powered by what is called a "warp drive" and at the moment only Paramount Pictures know its secrets.
But new, highly mathematical research may have brought us one step closer to being able to explore the Universe in a starship capable of travelling faster than the speed of light.
The analysis of the concept of a warp drive by Chris Van Den Broeck of the Catholic University in Leuven, Belgium means that building a starship Enterprise is a little closer.
The fabric of space
Dr Van Den Broeck was reanalysing ground-breaking calculations made five years ago by Mexican mathematician Miguel Alcubierre. Alcubierre said that it was possible to imagine how a warp drive would work by distorting the fabric of space. Starships would ride along waves in so-called spacetime, like surfers do along waves in the sea.
The idea relies on the concept that, to physicists, space is not empty. Strange as it may seem, space has a shape that can be distorted by matter. In fact the force of gravity is actually due to the curvature of space - recognising that was the greatest triumph of Albert Einstein's career.
So you could use matter to distort the space around a starship to create a "ripple" in spacetime.
The starship would have to be microscopically small on the outside but large enough on the inside to carry passengers, just like the Tardis in the British sci-fi series, Dr Who.
'Warp bubble'
Miguel Alcubierre came up with the idea of expanding the space behind a starship and contracting it in front of it. The starship would rest in a "warp bubble" between the two spacetime distortions. The result would be a wave in spacetime along which the starship would surf.
It was a fantastic idea. There would be no limit to the velocity that a starship could attain. It could travel faster than the speed of light because the starship would, strictly speaking, be stationary in the space of its warp bubble.
Also, the starship and its crew would be weightless and would therefore not be crushed by the enormous G-forces of acceleration and deceleration.
What's more, the passage of time inside the warp bubble would be the same as that outside it. The crew would not suffer from Einstein's "time dilation" effect where time passes at different rates for people travelling at different speeds.
The time dilation effect means that anyone travelling to the stars at speeds approaching that of light would experience a journey of a few years. But when they came back to Earth they would find that thousands of years had passed and all their friends were long dead.
Massive energies
Alcubierre's idea was a good one, but his work seemed to suggest that building a warp bubble would be impossible in practice. More energy than the entire universe could supply would be needed to create the spacetime distortions.
However, Dr Van Den Broeck's analysis suggests a far lower amount of energy is required, reduced by a factor of one followed by 62 zeros.
This is not to say that it is time to go out and start building a warp drive. As Dr Van Den Broeck says in his forthcoming paper in General Relativity and Quantum Cosmology: "This does not mean that the proposal is realistic."
Building a warp drive is currently far beyond our technological abilities and there are severe theoretical arguments that say it may never be possible.
But it just might be. Dr Van Den Broeck concludes his analysis by saying, "The first warp drive is still a long way off but maybe it has now become slightly less improbable."
Cap'n she's break'n up! I kinna hold it t'gether!!
This has already been proven by flying atomic clocks synchronized with the ground and showing how the clocks in the airplane run faster due to the (very) slightly lower gravity. I wonder if the author of the piece is getting it right?
That was Gravity Probe A. This is Gravity Probe B, which will test the dragging of spacetime. It's a sad time for bureaucrats, as this is the longest running project ever at NASA -- over four decades.
That's really kind of silly, since the left and academia and the "intelligensia" believe in tons of theories that haven't been tested and proven (though for THEIR theories the rules of proof don't seem to apply.)
Unless it's global warming and evolution.
I'll pay you $2000. FReepmail me and we'll work out the details.
'I remember......doing the TIME WAAAARRRPPP........'
Then you better not click here.
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