Starships. The idea captures the imagination, doesn’t it? But special relativity is a harsh law to live by if we, as a species, ever plan to make it beyond the constraints of our own solar system. It imposes the ultimate speed limit on the Universe. The speed of light. Nothing can travel faster than light. The only thing which can, in fact, travel at the speed of light is light itself. Aside from the fact that this would have made Star Wars significantly less exciting, this poses a problem. Is it even possible to travel to other stars within a single human lifetime?
The idea of a real life warp drive has been floated before, though it was found to require so much energy that even attempting it would be insane. As I recall, the fuel requirement was approximately what you’d obtain if you were to take three planet Jupiters and convert them to energy. Obviously, an engine more powerful than you could possibly imagine wouldn’t exactly be feasible as a technology.
But a recent study has breathed a new hope into the idea of a warp drive. Essentially, by modifying the ship’s design and how it would work (and I haven’t read the paper, so I don’t know the specifics here), such a warp drive could require dramatically less energy than previously thought, making it the fastest hunk of junk in the galaxy. And it would end up looking a bit like an olive suspended inside a bangle, apparently. Such a ship could be powered by a source about the size of a craft like Voyager I, and oscillating the intensity of the warp could reduce the power required even more – the same way in which pulsed lasers achieve a higher effective energy output from the same power source. I’m getting ahead of myself here. Allow me to explain the background…
As it happens, it’s all about how you interpret the laws set out by special relativity. Nothing can travel through spacetime faster than light. Not unless you believe those lying neutrinos. But it gets interesting when you realise that there’s nothing to stop spacetime itself from travelling faster than light. This might sound ridiculous at first, but it’s perfectly valid (and also, to directly quote Richard Obousy, president of Icarus Interstellar, “really cool”). For instance, in the colossal gravitational fields of black holes, spacetime itself can become warped. The spacetime around a rotating black hole actually gets pulled around like a ballerina’s skirt. Known as reference frame dragging, this is why objects orbiting black holes can appear to travel faster than light. From our perspective, they are travelling faster than light – but they aren’t travelling faster than light relative to their own frame of reference. That last statement is the key here. Enter Mexican physicist Miguel Alcubierre.
Alcubierre realised that if you were to literally warp spacetime, contracting it in front of you and expanding it behind you, it may enable you to travel faster than light in a region of perfectly flat spacetime. Anyone who’s watched Star Trek may be entertained by the fact that this has actually been termed a “warp bubble”. This would enable someone travelling in such a warp bubble to experience none of the bizarre relativistic effects (such as time dilation) that they might otherwise experience travelling at ludicrous speeds. Relative to the space around you, you’re not even travelling at all. It’s the space itself which is travelling, and it’s carrying you with it. Effectively, you’re creating a wave in spacetime and riding it like an interstellar surfer. Mind you, some mind melting consequences would still be possible while using such a mode of transport – see my Astrotropes: Faster Than Light article for more about that!
So could it be possible to actually warp spacetime? Well, Harold “Sonny” White at NASA’s Johnson Space Centre is actually conducting laboratory experiments to test the idea. With a sci-fi sounding device called the White-Juday Warp Field Interferometer, he and his colleagues are looking at the possibility of creating microscopically small spacetime warps (in a way which sounds not dissimilar to attempts made to detect gravitational waves). Currently they’re only trying to perturb spacetime by one part in 10 million and then trying to sense the disturbance. Baby steps. If it works though, it will be encouraging. Maybe we really could travel across the vast voids of interstellar space after all. If nothing else, in the meantime, it would speed up travelling around our own solar system dramatically.
From comments I’ve already seen, it would seem that some do not share my optimistic appraisal of the situation. It seems inevitable that there are going to be more naysayers talking about how we should all “stop daydreaming” and people willing to give thousands of reasons why not. I find their lack of faith disturbing. You could, after all, come up with reasons not to do practically anything. It wasn’t actually that long ago that people gave reasons why aeroplanes would never work, and claimed that building a train to travel faster than 20 miles per hour would be instantly fatal to any passengers★. Needless to say, trains and planes are now so commonplace that we don’t even question them anymore. So why not warp drives too? Why not indeed.
★ I have my suspicions that some people who work for CrossCountry Trains might still believe this to be true.
(And yes, the title of this post is a reference to ’80s pop music. What of it?),