Interested in time travel? Well you’ve come to the right place!
In the next 10 minutes, we’re going to cover everything you need to know to get started hopping around in the 4th dimension.
And you know what’s cool?
Once you’re done reading you can always go back in time to get that 10 minutes back 🙂
Well let’s start by addressing that huge grey thing that’s currently stomping around the room making a most unsightly elephant shaped mess…
Is Time Travel Actually Possible?
So what’s the answer? Well… yeah… kind of.
In fact, travelling into the future is actually quite simple. At least in theory.
Only problem is you’ll need to leave earth to do it.
And your spaceship will need to travel fast. Like, REALLY fast.
Ok, maybe not that simple then…
But DEFINITELY more simple than time travelling to the past. That’s a real doozy.
So let’s start with the future.
Special Relativity & Time Travel
You know that German dude Einstein? The guy you see on Facebook with quotes incorrectly attributed to him?
Well I’m sure you’re aware he was a super smart guy.
And one of his biggest bouts of mega genius was the theory of special relativity.
Special relativity states that the closer you get to the speed of light, the slower you will experience time relative to the people you left behind.
So if you managed to build (or steal) a spaceship that could travel at close to the speed of light, whizzed around in it for a few years, then came back to Earth, your mates would all have started drawing their pensions, listening to Genesis, and playing golf by the time you arrived.
Your 5 years in space would be 50 for those back here on Earth.
So that sounds easy enough. Only problem is you’d need to go WAY over the national speed limit to see the benefit.
In fact, to travel 45 years into the future, would require you to be doing around 99.5% of the speed of light.
So can we do that?
Well, the fastest human made object in history was the Juno spacecraft, which got up to 265,000 kilometers per hour (relative to Earth).
That sounds impressive.
Until you factor in that light travels at 299,792 kilometers per second!
Which is a staggering 1,079,251,200 kilometers per hour. A number so big I didn’t even know where to put the commas.
So the fastest human made object in history managed to travel at 0.0245% of the speed of light.
Still a bit to go then…
General Relativity & Time Travel
General Relativity was another one of Albert Einstein’s greatest hits.
And it gives us a second way of travelling into the future.
The good news is that this time we don’t need to worry about accelerating towards the speed of light. We just need to get close to something big.
According to General Relativity, the force of gravity is able to warp space-time.
(actually, according to the theory this warping IS gravity… but let’s keep things simple)
The greater the mass of the object, the greater the warping effect.
And if you’re close to a big, space-time warping object, you’ll experience time more slowly than someone further away.
Any object with a gravitational field warps space-time. As the Earth has gravity -- which conveniently stops us flying off into the cold, dark, vacuum of space -- our home planet is itself a space-time warper.
And actually, this is something that has been proven with experiments. Scientists have shown that atomic clocks at differing altitudes (i.e. different distances from the Earth) will eventually show different times.
But here’s the thing:
It might seem big when you look out your window, but in space terms, the Earth is TINY.
So its space-time warping capabilities are pretty weak. The difference in the clocks was a few nanoseconds at most.
For us to actually experience any meaningful time dilation (effectively time travel), we’d have to get close to something with a HUGE amount of mass.
We’re talking Susan Boyle after her 4th helping of Christmas dinner big.
Like a black hole.
Now as it happens black holes are actually quite small (at least in cosmic terms), but they are super super dense.
Supermassive black holes -- the biggest type, which can be found at the centre of most massive galaxies, including ours -- can cram millions, or even billions of times the amount of mass contained in our sun into the same area.
Which means they exert HUGE gravitational forces.
So what would happen if you hopped in your spaceship and flew directly towards one?
Well, first some caveats:
- We’re going to ignore the fact that if you actually were able to to do that some seriously CRAZY shit would happen to you. Shit like this.
- As you got closer and closer to the black hole, the speed at which you would need to travel in reverse to escape its gravitational pull would quickly get super high. In fact, you would eventually pass a thing known as the “event horizon” -- at which point you would have to travel faster than the speed of light to get out. And the laws of physics say you can’t do that. Damn.
Got it? Ok… this is where relativity is a bit of mind-bender.
Let’s say you are travelling in space with your mate Keith.
You decide to go on a little trip by yourself to the event horizon of a black hole and back again. You figure it will be a 10 minute trip, so ask Keith to stick the kettle on and watch you from the window.
What you experience
You jump into your mini spacecraft, fly up to the event horizon of the black hole, admire the (lack of) view, turn round and head back to your ship. It takes 10 minutes as expected.
You get back on board your ship, head over to where your buddy had been watching from the window, and trip over the Keith shaped pile of dust on the floor.
What Keith experiences
Keith sticks the kettle on, then heads over to the window to watch your trip. He notices that your ship is moving very slowly towards the black hole.
In fact, the closer your ship gets to the black hole, the slower it goes.
Eventually your ship stops moving completely.
Days pass and your ship stays in the exact same spot. Weeks pass, still no movement. Months… years… still no movement.
In his experience your ship is frozen in the same spot in space for an age. He keeps a vigil by the window until his dying day and never does get that cup of tea.
Congratulations. You have successfully travelled into the far future.
Get back to Earth (if it still exists) and you will be a time traveller. And if you’re really lucky, the monkeys won’t have taken over the planet.
So that’s two actual, laws of physics abiding ways to travel into the future. How about the past?
Time Travel To The Past
Ok, I’m not going to lie, figuring out how to time travel to the past is not easy.
And even if we could go back, it opens up all sorts of problems with paradoxes.
So to keep this simple, we’ll first run through a method of space travel which would definitely allow you to see a bit of the past, if not actually interact with it.
Theoretically this method does also offer us a way to actually travel to the past, but it gets WAY complicated.
This is all hypothetical at the moment.
It involves wormholes, which we haven’t actually proven exist yet. But they are predicted in Einstein’s general theory of relativity -- and he’s got a pretty high hit rate so far.
You’ll also need a telescope way more powerful than anything we have available right now.
Oh yeah, and the wormhole would almost certainly crush you to death.
Still. Moving on…
What Is A Wormhole?
Remember how big things warp space-time? Well a wormhole is basically a link between two points in warped space-time. A shortcut.
Let’s say you wanted to go on holiday to Alpha Centauri.
It’s a fair trek across space of 4.3 light years. Getting there is going to chew up all your time off work.
So what do you do?
Simple. You fold space-time to bring Alpha Centauri closer and fly through a conveniently opened wormhole. Something like this:
Whizzing down the wormhole, you arrive at Alpha Centauri in a matter of hours.
Ok, so you’ve successfully travelled 4.3 light years in less time than it takes to announce Daenerys Targaryen’s entry into a room.
Awesome. But what’s that got to do with time travel?
Well, here’s the thing:
You may have found a shortcut, but the light from Earth still has to go the slow way. It’s going to take 4.3 years to reach your vantage point in space.
Which means that if you had a telescope capable of actually making anything out, you would be looking at Earth 4.3 years in the past.
Which is not really that impressive.
So let’s think bigger.
For your next trip, you decide to open up a wormhole between a nearby black hole (the one at the center of the milky way would suffice) and the Virgo galaxy.
The Virgo galaxy happens to be around 65 million light years from Earth.
Which means that if you pointed a super, super, super, ridiculously strong telescope at our home planet, you would see a load of huge dinosaurs wandering around doing dinosaury things.
Interacting With The Past
Ok, so I mentioned that theoretically we could also actually travel into (and interact with) the past through a wormhole.
We definitely could in theory (here’s how), but we would only ever be able to travel back to the point that the wormhole was first opened up. Or to put that another way, when the time machine was invented.
So if we created a wormhole today, our ancestors might be able to come back to meet us, but we couldn’t actually go back in time ourselves.
Well, we could when we were older I guess.
Which means that if you ever invent a time travelling wormhole, the second it is finished, you’ll probably be visited by 50 generations of your descendants and future you. Which is probably a good reason NOT to invent a time machine.
So to clarify: current thinking is that, while time travel to the past might be possible in the future, we would only ever be able go back to the point when the first time machine was invented.
Which explains why, when Stephen Hawking threw a party for time travellers, no-one showed up.
Of course this is all based on our current understanding of physics. And we could be wrong.
So now let’s look at the big problem with time travel to the past.
The Trouble With Time Travel
You did it.
You managed to roundhouse kick the laws of physics in the face, and travel back in time.
So what do you decide to do first?
Witness the construction of the pyramids? Go and see The Beatles playing at the Cavern Club? How about seeing if that Jesus fellow was actually real?
Nah, you go back and kill your grandfather.
The Grandfather Paradox
The grandfather paradox has troubled philosophers and wannabe’ time travellers for decades.
The basic premise is that changing the past is logically impossible, ergo time travel to the past must be impossible.
How is changing the past logically impossible?
Well consider going back in time to kill your grandfather (before your father was conceived).
You do that and there’s no way you could have ever existed. Which means that you couldn’t have gone back to kill him in the first place.
Hence, the paradox. Hence, time travel being logically impossible. Hence my brain hurting.
So that’s a bit of a problem for time travel to the past.
Well, yes, maybe (lots of maybes involved in time travel).
Possible Solutions To The Grandfather Paradox
There are several ways round the grandfather paradox, which might make time travel to the past possible (at least logically if not practically).
The first is the multiple universes theory, which proposes that every possible reality exists simultaneously.
Think the movie Sliding Doors.
So if you go back in time and change something (in this case killing your grandfather), you will no longer live in your previous reality/universe. You will have effectively created a new timeline and jumped realities.
And you couldn’t go back to your former life, because you are now stuck in a reality in which you never existed.
Another theory is that the Universe will go out of its way to avoid paradoxes. So if you try to go back to kill your grandfather you simply won’t be able to do it.
You might be about to shoot him and your gun jams. Or maybe the Universe will just send a bolt of lightning to strike you down as you are about to stab him in the back.
Present you dies, your grandad lives, and baby you gets born.
And then there’s this trippy solution involving a closed time loop where the Universe exists simultaneously in 2 states…
So while presenting a challenge, the grandfather paradox doesn’t completely rule out time travel to the past.
Glad we cleared that up…
Evidence Of Time Travel
Have future time travellers already travelled back in time to our present and past?
The answer is… we don’t really know. But it’s certainly possible.
So, have they left us any evidence of their visits?
Here are links to read more about each of the pieces of ‘evidence’ featured in the video.
- Time travelling Jay-Z
- Helicopter hieroglyph
- Time traveller poses for photo in 1917
- John Titor
- Swiss watch in rock
- Time travelling hipster
- Project Pegasus
- Billy Meier
- The Philadelphia Experiment
- Accidental time traveller
- Mormon CD Rom
- Hyper Dimensional Resonator
- Kitchen wormhole
- Charlie Chaplin time traveller
- Adidas wearing mummy
A lot of the evidence is easily debunked, however, the John Titor story has intrigued me since I first read about it back in the mid 2000s.
If it was a hoax, then nobody has come forward to admit to it yet.
So, top trolling or time traveller? You decide.
Time Travel Survival Guide
Let’s say you manage to build a time machine and travel to the past -- perhaps even the distant past.
But just like Marty McFly, you get stuck and are unable to return to the future.
You’ll quickly realise that we take a LOT of things for granted. And that you probably don’t have the faintest clue how most things actually work.
Well bad news:
You probably won’t last long. A simple infection will likely finish you off.
But don’t worry, we’ve got you covered.
Here are some things you’ll need to know to survive, and perhaps even thrive, in the past.
Health And Hygiene
We’ll start with health. After all nothing else is going to be much use if you’re dead.
Note: the following advice should only be used if you find yourself back in time, or perhaps after a zombie apocalypse. If it’s available, always seek professional medical help.
Clean All The Things
- Keep yourself clean to help prevent the spread of germs
- Wash medical instruments in boiling water
- Use steam to wash anything that can’t be submerged in boiling water
If you have a wound and it gets infected, you’ll need to fight the infection with antibiotics.
Penicillin is the most effective form of antibiotic, and the good news is, it’s basically the mould you find on food.
The good news is that you’re probably already immune to most dangerous viruses.
But smallpox was a big killer until we eradicated it at the early part of the 20th Century. And as there hasn’t been an outbreak in the USA since 1949 we no longer vaccinate for it.
So you’ll want to vaccinate yourself asap.
You can do that with the cowpox virus, which is not dangerous to humans.
And it’s not a bad idea to learn a bit about vaccination, just in case.
In 2015, 9.4% of Americans were diabetic. Left untreated, diabetes can kill, so look out for the following signs:
- Frequent urination
- Extreme thirst or hunger
- Excessive weight loss
If you do have diabetes, you’re going to need insulin.
You can extract insulin from the pancreas of a pig by tying a string around its pancreatic duct. Inject the extracted insulin and it might just save your life.
Anesthetic will numb pain. Here’s how to extract a natural anesthetic gel from the Cattail.
And you can find a list of other natural anesthetics here.
Pasteurisation is a process which kills off nasty things (like bacteria) in food and drink.
Basically, what you want to do with liquids is heat them to a high temperature (below their boiling point) for a few minutes. It will make them safe to drink and they will also last longer before spoiling.
Here’s a super retro video which explains the process:
Here are a few technological skills that might come in handy if you end up stuck in the past.
How To Light A Fire
Stuck in the distant past? You’ll need to know how to light a fire to keep warm, create light, cook food, boil water, and perhaps even ward off predators. It’s pretty important!
Here’s how to do it old school style, by rubbing sticks.
How To Make A Simple Battery
Need to charge your time machine, but stuck in a period before electricity? Use a lemon, a copper coin and a galvanised nail to create a battery.
To generate sufficient power you’ll probably need to run a lots of these “cells” in parallel. More lemons = more power.
Need More Power?
A turbine can be used to convert kinetic energy (from wind, waves, steam, or even riding a bike) into usable energy.
Hook it up to a generator and you’ll get electricity.
Best Time Travel Movies & TV Shows
Time travel has been the subject of a ton of awesome TV shows and movies over the years.
So to keep you going on Netflix while you wait for time travel to be invented, here are some of our favourites.
Back To The Future (trilogy)
Time travel to the past, the future (well it was at the time), and the coolest time machine ever. What’s not to like?
Flux capacitor… fluxing!
The Terminator (and Terminator 2)
In a post apocalyptic future, sentient machines rule the earth and have wiped out most of humanity. Arnold Schwarzenegger is a killer robot sent back in time to ‘terminate’ the mother of the leader of the human resistance before he is born.
And then in T2 he’s sent back to protect him.
We wouldn’t really recommend T3, Salvation, or Genesys. Although we do hold out some hope for the next one.
Convict Bruce Willis is sent back in time from 2035 to 1990 to stop a devastating plague.
Another time travel movie starring Bruce Willis. This time he’s a hit man sent back in time to be killed by his past self. Because… um… watch the trailer…
Bill & Ted’s Excellent Adventure
Bill and Ted take an epic journey through time, picking up historical figures (and babes) to take part in their science project along the way.
The world’s longest running science fiction show, Doctor Who has been on the air since 1963 (there was a hiatus between 1989 and 2005, with a TV movie in 1996). If you’re a fan of time travel, then Doctor Who is essential viewing. And there is enough of it to keep you going for a long time!
Sam Beckett leaps from body to body, striving to put right what once went wrong.
Life On Mars
After being hit by a car, Sam Tyler (John Simm) wakes to find himself in 1973. Is he mad, in a coma, or back in time?
That wraps it up for our beginner’s guide to time travel.
If you have any questions, then please leave a comment below. And don’t forget to sign up for our email list for loads more cool content.
We hope to see you again in the future. Or the past…