The universe is a really strange place, and as science progresses, it just keeps looking weirder. So when fringe theories like the below come about, your first impulse is to laugh them off, but then you think, "Is it really that much stranger than what we know now?"
So we're not saying that any of these mind-blowing theories about the nature of everything are accurate, we're just saying that they were proposed by people smarter than us, and it's fun to think about how ...
In The Matrix, Keanu Reeves is horrified to learn that the universe he's been living in is actually a computer program designed by a giant, malicious robot intelligence, and that he's actually a hairless man-baby swimming in a vat of goop in the bowels of a dystopian machine-brain. That's about as fictional as science fiction can get, but there are working scientists in the real world who wonder seriously about the idea that we might be living in an actual Matrix.
"Shit. So that red pill wasn't Ecstasy."
First, there's British philosopher Nick Bostrom, who came up with a statistical argument that we're living in an extremely sophisticated version of The Sims. The idea is that we have the ability and the inclination to build our own simulated realities, as evidenced by the growing video game industry. Thus it's inevitable that we'll build our own Matrix one day, when our level of technology allows it. That simulation will continue to grow in realism and complexity until one day it will have its own civilization, who will want to build a simulation of their own, and onward to infinity.
How much pixelation do you have over your junk? If your answer is any at all, you're probably living in The Sims.
If that's true, then there might be a virtually infinite number of simulations out there, so the chances that we're one of them are actually much higher than the chances that we're not.
Then there's physicist Silas Beane from the University of Bonn in Germany. His theory is that, if we are actually living in a computer simulation, then our universe should have a "resolution" -- in other words, there should be a limit to how small something can be, just like nothing can be smaller than the pixels on your computer screen.
Now, is the universe in VGA or super VGA?
And, incidentally, they have found such a limit. It's something called the Greisen-Zatsepin--Kuzmin or GZK limit. It's about as technical as you'd expect for something with that many hyphens and consonants, but Beane thinks it might be the first evidence that the world around us is made up of artificial bits created by some other intelligence. Of course, this evidence might not be that compelling by itself, but Beane and his colleagues are busy thinking up new ways to detect the computer we might be living in, presumably by mapping the universe in search of the Blue Screen of Death.
Congratulations -- proof we're all living inside a computer! Also, everyone's now dead.
As with all of the fringe theories on this list, there are those who scoff at such a notion. And they will continue to, right up to the point that a team of superpowered Matrix Agents storm their office.
Almost every sci-fi franchise has done the "evil alternate-universe version of the main character" storyline at least once. They just can't resist a scene where the hero fights a dark, bearded version of himself. Well, if certain experts are right, your doppelganger is out there, somewhere.
Unfortunately it doesn't only work for hot people.
The theory goes that there are only a certain number of combinations of particles possible. Give a room full of kids a set of five LEGO blocks and a few of them are going to wind up building the same thing -- there are only so many ways they can fit together. Well, everything in our world -- including the people in it -- is just LEGO structures made of tiny particles. There's only so many possible combinations, and in a large enough universe, all those bits are inevitably going to wind up in the same place again and create another you.
It's not likely that you'll ever cross paths, though. Science's prediction is that your doppelganger lives about 10 to the 1028 meters away (or farther than you could travel by bus).
And even if you could, you'd probably have to sit beside this guy the whole way.
Nevertheless, the bigger the universe is, the more likely it is that there's another you walking around out there. Scientists don't actually know how big the universe is, by the way, but if it happens to be infinite -- which some think it is -- then the fact that you have a cosmic twin is downright certain. On an infinite scale, every pattern has to repeat eventually. The only possible question is, if you ever did run into your cosmic twin, would you fight or fuck?
String theory is like the eccentric uncle of theories about the universe. Not everybody is happy to see him, but you can't just not invite him to the family get-together. It's a theory that suggests, among other things, that the whole of the universe is stuck to a giant sheet of fabric that they call a "brane." Like all of reality is just a doodle on the back of a coffee-stained napkin.
Oh great, Uncle String Theory is here with more of his stories.
What's more is that we're not the only brane out there. There should be other branes floating around in the cosmic nothing that lies outside of our own universe. These would all be parallel universes. It's kind of a Doctor Who fan's wet dream. The terrifying thing is that there aren't any cosmic traffic cops out there, so there's nothing stopping one universe from smacking into another one.
What would that look like? University of California physicist Anthony Aguirre thinks it would be like a giant mirror coming down at us from the heavens so that the last thing we see is our own horrified expressions as we immediately understand the fact of our impending obliteration. Although he didn't quite put it like that.
"No! No! I don't want to die staring at my own stupid hipster beard!"
If this was even possible, then it should have happened before, right? Well, physicists are rarely in the business of putting us at ease. Tufts University physicist Alex Vilenkin and his colleagues think they may have found the scars of a collision between our universe and another one at some point in our history. The "cosmic microwave background" is a faint radioactive signal that permeates the entire universe, and all of science's calculations insist that it should be pretty uniform across the universe. But it isn't -- there are hot and cold spots in some places. Vilenkin and Co. think that this disruption might be evidence that other universes have been smacking into ours.
Again, other people think they're crazy, we're just passing it along.