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NASA engineer Harold White stunned the aeronautics world when he announced that he and his team at NASA had begun work on the development of a faster-than-light warp drive. His proposed design, a re-imagining of an Alcubierre Drive, may eventually result in an engine that can transport a spacecraft to the nearest star in a matter of weeks—and all without violating Einstein’s law of relativity—nothing with mass can accelerate to light speed.

The idea came to White while he was considering an equation formulated by Mexican physicist Miguel Alcubierre. In his 1994 paper titled, “The Warp Drive: Hyper-Fast Travel Within General Relativity,” Alcubierre suggested a mechanism by which space-time could be “warped” both in front of and behind a spacecraft.

Alcubierre’s notion takes advantage of a quirk in the cosmological code that allows for the expansion and contraction of space-time, and could allow for hyper-fast travel between interstellar destinations. Essentially, the empty space behind a starship would be made to expand rapidly, pushing the craft in a forward direction—passengers would perceive it as movement despite the complete lack of acceleration.

(Think of this bubble like a moving sidewalk: It carries you faster than you can walk, but your leg muscles still dictate how fast you can walk on the rubber surface. In the case of the space-time bubble, the “sidewalk” is moving faster than light, while objects inside that bubble still obey the speed limit.)

Concept for warp drive craft. Photo: Michael Stravato for the NY Times

In terms of the engine’s mechanics, a spheroid object would be placed between two regions of space-time (one expanding and one contracting). A “warp bubble” would then be generated that moves space-time around the object, effectively repositioning it—the end result being faster-than-light travel without the spheroid (or spacecraft) having to move with respect to its local frame of reference.

“Remember, nothing locally exceeds the speed of light, but space can expand and contract at any speed. However, space-time is really stiff, so to create the expansion and contraction effect in a useful manner in order for us to reach interstellar destinations in reasonable time periods would require a lot of energy.” ~Harold White

Early assessments published in the ensuing scientific literature suggested horrific amounts of energy—basically equal to the mass-energy of the planet Jupiter (what is 1.9 × 1027 kilograms or 317 Earth masses). As a result, the idea was brushed aside as being far too impractical.

The key, says White, may be in altering the geometry of the warp drive itself.

White has redesigned the theoretical warp-traveling spacecraft—and in particular a ring around it that is key to its propulsion system—in a way that he believes will greatly reduce the energy requirements.

White says, “I suddenly realized that if you made the thickness of the negative vacuum energy ring larger—like shifting from a belt shape to a donut shape—and oscillate the warp bubble, you can greatly reduce the energy required—perhaps making the idea plausible.” White had adjusted the shape of Alcubierre’s ring which surrounded the spheroid from something that was a flat halo to something that was thicker and curvier.

White’s new new design could significantly reduce the amount of exotic matter required. And in fact, White says that the warp drive could be powered by a mass that’s even less than that of the Voyager 1 spacecraft.

That’s a significant change in calculations to say the least. The reduction in mass from a Jupiter-sized planet to an object that weighs a mere 1,600 pounds has completely reset White’s sense of plausibility—and NASA’s.

The warp drive design appears to be based on an exotic form of matter that nobody has seen experimentally.


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