Real-life warp drive may power future spaceships
The US National Aeronautics and Space Administration (NASA) is looking at a reimagined version of the controversial Alcubierre Drive to build a "faster-than-light" warp drive that can cut travel time to the nearest star to just weeks.
Physicist Harold White's design is based on an equation by physicist Miguel Alcubierre, who in his 1994 paper suggested a mechanism where space-time could be "warped" both in front of and behind a spacecraft.
"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," White told tech site io9.
But the amount of energy is quite considerable: equivalent to the mass-energy of the planet Jupiter or 317 Earth masses, making it impractical, at least for now.
"Mathematically, the field equations predict that this is possible, but it remains to be seen if we could ever reduce this to practice," he said.
The io9.com article said Alcubierre's notion has been considered a "passport to the universe" as it exploits a "quirk" in the cosmological code that allows the expansion and contraction of space-time.
It runs on the theory that empty space behind a starship would be made to expand rapidly and push the spacecraft in a forward direction.
"This loophole in general relativity would allow us to go places really fast as measured by both Earth observers, and observers on the ship — trips measured in weeks or months as opposed to decades and centuries," he added.
White speculates such a drive could take a spacecraft to Alpha Centauri —which is 4.3 light-years away— in just two weeks.
Using Alcubierre's notion, a spheroid object could be placed between two regions of space-time, one expanding and one contracting.
A warp bubble would be generated, moving space-time around the object, which can travel faster than light without "moving."
Hope for warp drive
White said his analysis in the last 18 months promises some hope, with the key lying in altering the geometry of the warp drive itself.
"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," he said.
Theoretically, he said the warp drive could be powered by a mass less than that of the Voyager 1 spacecraft.
"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," io9.com said.
White said he is using a modified Michelson-Morley interferometer that allows the team to measure microscopic perturbations in space time.
"In our case, we're attempting to make one of the legs of the interferometer appear to be a different length when we energize our test devices," he said.
He and his team are trying to simulate the tweaked Alcubierre drive in miniature by using lasers to perturb space-time by one part in 10 million.
"We will increase the fidelity of our test devices and continue to enhance the sensitivity of the warp field interferometer — eventually using devices to directly generate negative vacuum energy," he said.
White noted that in late 1942, humanity activated the first nuclear reactor in Chicago, with the facility generating only a half-Watt.
Yet, in less than a year, a ~4MW reactor was activated, enough to power a small town.
"Existence proof is important," he said.
But for now, he said pursuit of this idea is very much in science mode, saying he cannot discuss much "beyond the math and very controlled modest approaches in the lab." — TJD, GMA News