Earlier this month, scientists and engineers were able to discuss their warp drive concepts at the 100 Year Starship Symposium in Houston, Texas, and there was some good news for sci-fi fans everywhere: the warp drive might not be as energy hungry as previous studies suggested.
Sonny White of NASA's Johnson Space Center presented his calculations on the energies required to travel faster than Einstein's famous speed limit: the speed of light. By White's reckoning, his design of starship -- that is "adjusted into more of a rounded doughnut, as opposed to a flat ring" and oscillates the warp intensity -- could be powered by the approximate mass-energy of the Voyager 1 space probe.
Although "the mass-energy of the Voyager 1 space probe" may not sound like much, if you convert the 722 kilogram Voyager mass into raw energy (using Einstein's famous mass-energy equivalence equation: E=mc2), White's warp drive would require 6.5x1019 Joules (65 exajoules) to create a warp bubble. That's nearly the entire annual energy consumption of the United States.
Clearly, this monstrous energy requirement isn't practical, but it's one heck of an improvement over previous estimates.
A Universe Of Energy
In 1994, physicist Miguel Alcubierre was widely credited to be the first to put some real physics into the warp drive. Although Star Trek would have us believe that you just need some dilithium crystals and a starship captain to point his finger, saying "Engage," Alcubierre discovered that the warp drive was theoretically possible, but it would need all the energy in the entire universe to function.
Alcubierre realized that for a spacecraft to travel faster than the speed of light -- something that Einstein's Special Theory of Relativity prohibits -- the spacecraft would need to somehow create a warp "bubble" around it. This would allow the spacecraft to be contained within its own region of spacetime. If the bubble can be controlled, then the light-speed limit can be exceeded in 'normal' space -- the spacecraft itself would be stationary whereas the bubble in spacetime will zip around at, effectively, infinite speed.
As described by Eric W. Davis, senior research physicist at the Institute of Advanced Studies in Austin, Texas, and co-author of Frontiers of Propulsion Science, the warp drive can be envisaged as a means of "surfing" through spacetime:
"Think of space as the ocean and Michael Phelps is a starship. He's propelled by fission or fusion rockets -- any kind of rocket -- but he's swimming vigorously, leaving planet Earth and he's going to swim all the way to Alpha Centauri, 4.3 light-years away. He's flailing his arms, kicking his feet, expending a great deal of energy and he can't go very fast ... the resistance of the ocean water is going to keep him limited to below the speed of light. Einstein's special theory says you can't go faster than light, you can't even reach it, but you can always stay less than (light-speed). Warp drive is a whole different matter. What you do is use "exotic energy" ... basically just a fancy word for vacuum energy. You're going to use some quantum energy from the vacuum and you're going to surround your starship with a bubble of this energy and it bends space -- it creates a surf effect. Michael Phelps is now standing on a surfboard and instead of swimming through space at less than the speed of light, he's surfing on space. Space is like the wave on the ocean water that surfs him to the beach faster than the speed of light." -- Eric Davis on "Attack of the Show"
Fill 'er Up with One Jupiter
Although Alcubierre's calculations showed that unimaginably huge amounts of energy would be needed to create this warp bubble, recently, Richard Obousy, co-founder and president of Icarus Interstellar (a key partner of the 100YSS), used our new understandings of quantum mechanics and applied them to the warp drive's 'bubble.'
Obousy's approach is to manipulate dark energy -- the mysterious force that appears to permeate the entire Universe, causing it to expand -- in such a way that extra dimensions (as predicted by string theory) can facilitate the creation of a bubble of spacetime.
"Given that extra dimensions have not yet experimentally been shown to exist, and the idea that dark energy is an artifact of these extra dimensions is somehow related to these dimensions is clearly highly theoretical," Obousy told Discovery News, "however it provides us with an interesting perspective from which to examine the problem."
Although this method would theoretically allow a Alcubierre-like solution to traveling faster than the speed of light, vast amounts of energy would still be needed -- the approximate mass-energy of Jupiter! -- but at least it's an improvement from the "all the energy in the Universe" solution.
Referring to White's work, Obousy continued: "The Jupiter calculation was purposefully created as an 'upper bound' to the problem, and I'm glad that the work performed by my colleagues has demonstrated ways to reduce the energy requirements down further."
Read more at Discovery News
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