Tuesday, 8 April 2014

Beyond the Solar System
Harold White, PhD, is a NASA veteran who runs the advanced propulsion program at Johnson Space Center.  His particular area of research is "warp drive."  
Warp drive is the only technology that could (even theoretically) permit faster-than-light travel, which under normal circumstances involves a clear violation of Einstein's theory of special relativity. 
Why is this so exciting?  A functional warp drive would have tremendous implications for space travel.  Today, it would take a NASA satellite 75,000 years to get to Alpha Centauri, the star system nearest to our own. 
However, according to White, a vehicle equipped with a warp drive could make the trip in just two weeks, while converting 1,600 pound of matter to energy.1
To underscore its relevance, the head of NASA, Charles Bolden said, "One of these days, we want to get to warp speed.  We want to go faster than the speed of light, and we don't want to stop at Mars."   
About 20 years ago, a physicist named Miguel Alcubierre was doing graduate work in general relativity.  After watching a Star Trek episode, he asked himself, "What would it take to make warp drive physically plausible?" 
In 1994, his answer was published in the form of a peer-reviewed paper in the journal Classical and Quantum Gravity.  That paper carefully outlined the physics that would be involved in the creation of a faster-than-light warp drive.2 

Konstantin Kakaes, a Schwartz fellow at the New America Foundation, recently described Alcubierre's thinking this way:
     "Alcubierre envisioned a bubble in space.  At the front of the bubble, space-time would contract, while behind the bubble, space-time would expand (somewhat like in the Big Bang).  The deformations would push the craft along smoothly, as if it were surfing on a wave, despite the tumult around it.  In principle, a warp bubble could move along arbitrarily quickly, because the speed-of-light limitation within Einstein's theory applies only to objects within space-time, not to distortions of space-time itself.  Within the bubble, Alcubierre predicted that space-time would not change, leaving space travelers unharmed.
     "Einstein's equations of general relativity are very difficult to solve in one direction—figuring out how matter bends space—but going backward is fairly easy...

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