Now that we’ve been to the moon, built the International Space Station, and landed a multi-billion dollar robot on Mars, space geeks are getting restless. Where are we going next? Well, going to Venus is probably boring, and we’d have to fly through the asteroid belt if we wanted to get to Saturn. Our next best option? Invent a warp drive and zip over to another star system, of course.
Science fiction authors have been obsessed with the concept of a warp drive — a space-time bending contraption that would enable us to travel faster than the speed of light — for ages. But a NASA scientist now says he can build it. Dr. Harold “Sonny” White is the Advanced Propulsion Theme Lead for the NASA Engineering Directorate, and is in the early stages of testing a system he thinks could transport us light years into space and possibly land us on a planet in another solar system. “Perhaps a ‘Star Trek’ experience within our lifetime is not such a remote possibility,” wrote Dr. White in a blog post.
The basic idea behind White’s warp drive is simple. Or rather, it can be easily simplified. Essentially, to make a space ship move faster than the speed of light, you don’t actually move the space ship. You move the space around it in such a way that the ship arrives at its destination faster than light would. This involves creating “warp bubbles” that actually compress the space ahead of the ship and expands the space behind the ship, thus carrying the ship to a new place without the ship really moving. With this method, White says, the ship will theoretically be capable of an effective velocity that’s ten times the speed of light. Meanwhile, as the universe zooms by its windows, the time inside of the ship moves at the same speed as it does on Earth. So instead of the 75,000 years it would take to reach Alpha Centauri with our current technology, it would take only two weeks with White’s warp drive, and you wouldn’t age any differently that you would at home.
If this all sounds like it’s too futuristic to be true, that’s because it is. NASA has actually been sitting on a widely accepted theory about bending space-time to travel faster than the speed of light for nearly 20 years. Mexican theoretical physicist Miguel Alcubierre outlined a theoretical warp drive that would take advantage of these so-called warp bubbles back in 1994, and in fact, White’s drive is based on the same basic principles as Alcubierre’s. The Alcubierre drive moves space-time around a ship in a warp bubble creating the effect of moving faster than the speed of light. Leaning heavily on Einstein’s Theory of Relativity, the theoretical physics of the Alcubierre drive check out, but there are also some serious problems with the plan.
The proposed Alcubierre warp bubble, with “opposing regions of expanding and contracting spacetime” surrounding a central point, like a ship. Via Wikipedia
Just like a traditional space ship, a warp drive-equipped ship needs fuel and lots of it. (Space-time doesn’t just move on its own!) According to some estimates, the Alcubierre drive would need a tank of gas equivalent to the mass of Jupiter in order to create a single warp bubble. Unfortunately, they don’t make gas tanks in that size. White, however, thinks he’s come up with a solution. He says “that the energy requirements can be greatly reduced by first optimizing the warp bubble thickness, and further by oscillating the bubble intensity to reduce the stiffness of space time.” This sounds like the same principle behind breaking in a new baseball glove. White says this technique theoretically “yielded a reduction from Jupiter amount of exotic matter to an amount smaller than the Voyager 1 spacecraft (500kg) for a 10-meter bubble with an effective velocity of 10c, which is a handy improvement.” 10c is ten times the speed of light.
Then there’s the issue of brakes. The warp drive can get a space ship to move impossibly fast across the universe, but it doesn’t offer a great way to stop it once it gets to its destination. Physicist José Natário pointed this out in a 2002 paper that explained how it would be impossible to steer or stop the ship once it’s in a warp bubble because it would be impossible to send signals from the back to the front of the bubble. So the interstellar pilots might set sail for Gliese 58g, an Earth-like planet about 20 light years away, but end up in another galaxy.
We also haven’t addressed the issue of obstacles. As the warp drive-powered space ship zooms across the universe, it’s most certainly going to run into some cosmic particles. These wouldn’t crack the ships windshield but would actually accumulate around the bubble. Again, this is bad news when it comes time to stop. “When the Alcubierre-driven ship decelerates from superluminal speed, the particles its bubble has gathered are released in energetic outbursts,” explains Jason Major from Universe Today. “In the case of forward-facing particles the outburst can be very energetic — enough to destroy anyone at the destination directly in front of the ship.” So you can travel to the nearest planet capable of supporting life. You just might destroy all of that life when you get there.
I’ll stop short of getting into the more advanced scientific challenges of the warp drive. It needs negative energy to work, for instance, but scientists have yet to discover negative energy. Instead, I’ll just wish Dr. White luck. Good on him for being so confident about cracking one of the thickest shells in theoretical physics, and hooray if comes up with a way to take us to the next star system. We’ll have to name a middle school after him or something when that happens.