Part of the joy of science fiction is seeing all the awesome toys, and imagining how they could exist in the real world. And so many of science fiction's coolest gadgets have come true, including Star Trek's PADDs and communicators.
But the sad truth is, a lot of the most fantastic technologies in science fiction are fantastic for a reason — they can't ever exist in reality. Here are 10 amazing technologies that will never exist in real life.
Aside from the sheer impracticality of this weapon — and not to mention how hazardous it would be to wave one of these around — the Star Wars lightsaber will almost certainly never come to be. The first engineering challenge would be in figuring out a way to stop the beam of light about two feet from the source. Light simply does not work in this way, unless there's something to obstruct or absorb it. Similarly, a highly concentrated beam of light wouldn't be able to cut through materials, or face resistance when striking another lightsaber. Assuming, therefore, that it's not actually a "light" saber, but rather some kind of plasma-beam saber (one that's available in a delicious assortment of colors), the intense heat would likely melt the handle — and possibly burn the Padawan to a crisp. There's also the power source to consider; these suckers pack quite a punch, deflecting laser beams and cutting through solid metal walls, so they would likely require something substantially more powerful than a pair of double-A's. A power source that powerful doesn't, and can't, exist.
2. Human Teleportation
A staple of the Star Trek universe is the capacity to beam, or teleport, humans from one location to another. As legend has it, Gene Roddenberry came up with the idea as a work-around to filming expensive scenes involving ships taking off and landing. But his idea slashed both the budget and common sense. Yes, quantum teleportation has been demonstrated in the lab — but spawning a pair of entangled photons across vast distances is a far cry from teleporting an entire human body. Moreover, Star Trek's teleportation scheme involves what's called "destructive copying," meaning that the source person must be obliterated (as evidenced in the TNG episode "Second Chances" when you accidentally get two Rikers). So, even if teleportation is somehow possible, it doesn't solve the problem that you'd be stepping into a suicide machine. And finally, the physical and energy requirements of teleportation simply won't allow for it. The system would have to be capable of the instantaneous scanning, recording and relaying of all 1045 bits of information that make up the human body, then transmit all this data to the destination, and finally compile the person without so much as putting a single molecule out of place. You go first.
3. Time machine
Thanks to Albert Einstein we know that time travel is possible. If you think about it, we're all time travellers, inexorably moving forward into the future without even having to think about it. But more conceptually, Einstein's theories have suggested that "wormholes" can connect two disparate regions of space and time, potentially allowing for the creation of time machines. Okay, great — so knowing that, now what do we do? Well, according to physicist Michio Kaku, we would need to extract the energy of an entire star or black hole — easier said than done. And then there's the challenge of stabilizing the wormhole and ensuring that the aperture (or wormhole entry point) remains open for the return journey (one way trip into the past, anyone?). But even if physics is on our side, metaphysics is not. The "grandfather paradox" suggests that any technology that lets you kill your own ancestor can't possibly exist, because it would break the cosmos. But there's an even tougher paradox to consider: If time travel is possible, then where are all the time travelers from the future?
4. Faster than light travel
Unlike time travel, which at least has some (reasonably) viable science behind it, the suggestion that we'll eventually be able to travel faster than the speed of light (FTL) is a clear and present violation of Einsteinian physics. The universe has a built-in maximum clock speed against which all linear processes are measured, including the propagation of matter and information. There has been some speculation that Einsteinian relativity allows for FTL particles to exist, what are called tachyons — but recent insights have largely put this idea to rest. First, there is simply no evidence for their existence. And second, they couldn't possibly exist because their presence would allow for FTL information transfer — a clear violation of causality. And more to the point, even if they are eventually discovered, it's highly doubtful that we could take advantage of the tachyon phenomenon to create a warp or Alcubierre drive. The intense energy requirements alone violate plausibility — an estimated energy equivalent of -1064 kg would be required for the effect — which is more than the mass of the entire Universe itself! Lastly, it would be impossible for the ship to send signals to the front of the FTL bubble, meaning that the crew members could not control, steer, or stop the ship — kind of a problem. And assuming the ship could somehow be stopped, its massive expenditure of gamma rays and high energy particles would completely annihilate anyone waiting at the destination.