The dream of faster-than-light travel has been on the mind of humanity for generations. Until recently, though, it was restricted to the realm of pure science fiction. Theoretical mechanisms for warp drives have been posited by science, some of which actually jive quite nicely with what we know of physics. Of course, that doesn’t mean they’re actually going to work
NASA researchers recently revisited the Alcubierre warp drive
and concluded that its power requirements were not as impossible as once thought. However, a new analysis from the University of Sydney claims that using a warp drive of this design comes with a drawback. Specifically, it could cause cataclysmic explosions at your destination.
To see how the Alcubierre drive could devastate an entire star system, you have to know a little about how it would work. The ship would consist of a central pod, and a large flattened ring around it (pictured below). The ring would have to be made of an as-yet unidentified kind of dense exotic matter capable of bending space-time.
Supply the craft with enough energy, and the very fabric of the universe can be warped. NASA now believes this would require orders of magnitude less energy than Alcubierre originally thought. When activated, space behind an Alcubierre drive expands while contracting in front. The ship itself hums along in a stable pocket, or bubble in space. It turns out the bubble is the problem.
As your faster-than-light ship sails through the cosmos, it’s not alone. Although we often think of space as empty, there are loads of high-energy particles shooting through the void. The University of Sydney research
[PDF] indicates that these particles are liable to get swept up in the craft’s warp field and remain trapped in the stable bubble.
The longer the journey lasts, the more of these dangerous particles build up. This doesn’t affect the ability of the warp drive to keep bending the laws of the universe — it’s the stopping that’s going to ruin your day.
The instant the Alcubierre drive is disengaged, the space-time gradient that allows it to effectively move faster than light goes away. All the energetic particles trapped during the journey have to go somewhere, and the researchers believe they would be blasted outward in a cone directly in front of the ship. Anyone or anything waiting for you at the other end of your trip would be destroyed.
Because of a funny little quirk of relativity, there is no upper limit to the amount of energy a Alcubierre drive could pick up. A long trip could vaporize entire planets upon your arrival. The researchers are beginning a new round of number crunching to see how bad the problem is. It’s possible the deadly particle beam could be projected in all directions, making Alcubierre drives unworkable. That spiffy warp ship might make a better weapon than method of transportation.
The Alcubierre drive is, of course, still highly speculative. NASA scientists are working with small-scale models in an effort to produce localized distortions in space, but this new Aussie research could give NASA something to think about. Even with future advances in technology, this method of space flight might prove to be impossible. At least then we wouldn’t have to worry about annihilating everyplace we try to explore.