Stephen Hawking will tell you that you can’t travel back in time. Don’t believe a word he says; because he doesn’t say anything really. That mechanical voice might seem like something out of a bad sci-fi B movie, or a soft-core porn mock up, but supposedly it is the man’s voice transcribed by a computer or something. I couldn’t be bothered Googling ‘how does Stephen Hawking speak?’ to find out. But who knows if that is really him talking?
But Stephen Hawking/Alien mind controller is pretty convincing. You can’t travel back in time and it is all the fault of your grandfather. The solution then is simple; you go back in time and kill your grandfather. Except of course by killing him you wipe out his lineage, which somewhere down the line includes you. So if he is dead, then you never existed. So who killed him? Aha! But what if you were adopted? Then you’d kill your grandfather and still be alive! Except of course he wasn’t your real grandfather. And the knowledge will seep in when you end up back in the present day a beggar on the street. Which would be a pretty sick way to find out you were adopted, especially with serial killers on the loose. And if you do get your head done in, that would be precisely what you deserved for thinking you’d found a loophole around the Grandfather Paradox.
So Stephen Hawking smugly asserts thus, with a diabolically raised eyebrow, that Back to the Future was full of holes. The fiend!
But wait. H.G Wells wasn’t completely full of jizz. There is such a thing as a time machine and it can take you to the future. In a one way ticket kind of way of course. Which wouldn’t be fun really, since the whole point of going to the future is to be able to come back with souvenirs like the I Phone 10G to impress your friends with. But presumably Stephen Hawking doesn’t have friends, which is probably why he is so brainy. So here are two un-time tested methods to get to your best mate’s 50th birthday looking like a million bucks.
Method 1: Orbit around a Super-Massive Black Hole
A super massive black hole is well, massive. Meaning it has a lot of mass. Such a lot of mass in fact that the sheer power of its gravity will suck its own body in to ultimately become a single point in space and time. This gives me a great idea for a ‘get thinner by eating more’ lifestyle video but more on that later. There is a super massive black hole in the center of our galaxy. It is surrounded by a humongous area of darkness because guess what, its gravity sucks in light as well. Your mission then is to grab a spaceship, race to the center of the Milky Way and somehow figure out the precise velocity and trajectory required to enable you to circle around the SMBH without getting sucked in and having your atoms instantaneously split apart one by one.
The logic is this. Einstein has proven that time is affected by mass. Heavy bodies such as the earth literally slow down time; satellites orbiting the earth find that their clocks run a bit faster when out in space and if they didn’t auto adjust to correct this your GPS system will point you 6 kilometers away from where you really want to go. Disastrous if you were parachuting to somewhere like the Maldives.
Theoretically, if you spend enough time under a pyramid in Giza (which weighs 40 million tonnes), or date Monica Lewinsky time should slow by a few billionths of a second every year. But if you’re not exactly the patient sort then it makes sense to head to the heaviest object in the galaxy.
But even there time only slows by half. 2 days on earth will be just one day spent orbiting the black hole. Not enough to get to the year 3000 alive? Then perhaps you should opt for
Method 2: Travel really, really fast
And I mean really really fast; as fast as light. Of course you can’t travel faster than light (because it is impossible; pfft) so all we can hope to do is reach speeds that are 99.9% the speed of light. When this happens, time slows down to prevent us from travelling any faster. There is a cosmic velocity limit that the universe must adhere to. Einstein has proven this as well, but I am in no way professing the remotest understanding of General Relativity.
But getting into a tuk tuk with your fingers crossed may not be the answer. Even Apollo 11, the fastest thing ever built by man, travelled at only a paltry 25000 kilometers a second (sheesh, get a move on humans!) while what is required is a speed some 2000 times greater. Your mission then, is to build a machine that is capable of achieving such speeds and to find an open space to drive it on lest you crash into your garage and irritate your father. Your best bet for such a space is well, space. So another spaceship it is.
This method yields better results. At top velocity, which will take some 4 years to achieve in a ship massive enough to take on the task (I don’t know why it is supposed to be big, he didn’t say or I wasn’t listening), you will be hitting a sweet one year on earth for every day on the ship. Carry all the books and TV series downloads you can, and before you know it you are alert and guest starring on Futurama.
Now presumably the universe is a sphere, and if you head out for long enough in a straight line (this poses numerous other problems; *points frantically* PLANET!) then you will end up back where you started, but I have no idea how long that will take. The whole argument is somehow proven by the particle accelerator where particles with short life spans last up to thirty times as longer when sent through the contraption at near light speeds. It’s real alright.
But as for travelling to the past, you can’t. Wormholes are your only way to do it and even they collapse like speakers with too much feedback because of the sheer overload of paradox seeping though. And that is about as much as my knowledge of physics can take for now.