So Stephen Hawking describes in his new Discovery Channel show, Stephen Hawking’s Universe, how a ship traveling at a speed approaching that of light’s would experience a temporal discrepancy from that on earth, enabling the crew to experience time at a fraction of that which we currently experience it. Basically, one day on board a vessel moving at 650 million miles per hour (98% the speed of light, according The Daily Mail) would be equivalent to an earth year, an event known as relativistic effects, which has been described to a degree by time dilation in Special Relativity and utilized heavily in science fiction for many years; Stephen Hawking believes that if one were capable of building a craft able to achieving near-light speed, these effects could in fact be demonstrated. Here, Queen discuss relativistic effects in the song ’39 from Night at the Opera. We’ll continue with what’s stopping such a ship capable of near-light speed from being built after the jump.
The only thing stopping Hawking from commissioning crazy Brits to build such a vehicle is that as energy production stands right now, this ship would have to be gargantuan, to hold all the fuel that will power this voyage on the light fantastic. Because otherwise, Hawking would be all over this idea like stadium cops on their tasers; he’s, to quote, not as “cautious” as he used to be, which is why he’s throwing caution to the wind and declaring something we’ve kinda figured for the last hundred and fifty years (see Special Relativity). There are some major problems with such a construction otherwise, which include materials, food, and potable water, which we’ll tackle a little further down. Let’s hit the big issue first.
Primary energy production today is a major issue on this planet – the amount of fuel we burn through to achieve that energy is extremely limited and dwindling fast. This makes access to liquid fuels for a near-light speed travel of this magnitude impossible, considering it would require a vast amount of it, probably so much as to bankrupt our current stores. The answer to this, of course, is nuclear fusion. That’s where you take two particles and mash them together. We already know how powerful fission is, but it’s got nothing on fusion: fusion’s what powers suns. For rizzle.
Research into fusion has been going on since the 1940’s, starting with the Manhattan Project, and continues to this day. Currently there are three leading methods nearing working success: the tokamak system, the Z-pinch system, and the laser system. The first system utilizes magnetic confinement to hold the atoms which are heated to a plasma soup (because no physical container could hold the stuff); the second system super-heats tendrils of wires (making a plasma very efficiently) and compresses it in a magnetic field; the last shoots an ass-ton of lasers down “a hallway” wherein it makes a super-laser beam that’s equivalent to 1.8+ megajoules. As of yet, none of these systems have been able to be brought to the “break-even” stage, where the energy taken to release the energy is equivalent or greater than that generated. However, the moment it happens, a fusion power source would solve the most fundamental part of near-light travel: the sheer size of the space-craft.
That problem solved, we need to confront some of the other problems. Like making an engine that’ll get up to near light speed. Or creating a hull that can stop micro-asteroids from whizzing through it (I recommend a polymer made from carbon nanotubes and aerogel). Then there’s the problem of oxygen production: it could be staved off by growing plants on board, but would plants behave normally at near-light speed? If you figured all this out, you’d have to find a group of people that wouldn’t mind drinking their own sweat and urine for a mission’s length (besides fixing the kinks in the current system), because how else would you get enough water on board for everybody? You might want to bring along some juice concentrate.
Despite Hawking’s assessment that people traveling at near-light speeds would experience time differently than we do here on earth, I’m of the opinion that we’ll never know, in our lifetimes for certain, whether its fact, considering all the obstacles involved in making such a machine at all. Sure, we’ve got some of the technologies necessary, and are developing others that would also be needed, but in all, there’s a lot of components that science just doesn’t have yet. So how about you stop postulating, Hawking, and get your ass back in the physics lab where it belongs, huh?