Question: do you think that time travel will ever be possible? and if you do, do you think that we could only travel into the pat or only into the future, or both?

Oliver Gordon answered on 8 Mar 2019: last edited 8 Mar 2019 2:32 pm

This is a really cool question, and I want to answer it. Unfortunately it’s a really complicated explanation, so it might take a while! If you don’t understand please ask me to explain more, or ask me in the live chat!
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It’s theoretically possible already, just not like in the film back to the future…
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Time dilation is a real thing that we know about. If you experience time dilation, you go forwards in time, not back. This works because of a pretty simple bit of maths, but very subtle explanation.
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When we talk about the speed of things, we actually mean velocity. Velocity is speed in a given direction. And it’s all relative – when you sit still in a car moving FORWARDS at 50 mph, it’s mathematically the same as the road moving backwards at 50 mph.
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In other words, if you and your best friend go into space, your friend could think THEY are running away from you and YOU are standing still. But you could that YOU are running away and THEY are standing still!
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You are both correct – you have different “frames of reference”.
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This seems weird. But get this – we can use this to our advantage! Because light isn’t infinitely fast, it takes light a certain amount of time to reach you. Now, going back to you and your friend in space, imagine I’ve given you both a clock. The clock you hold has the time where you are, and the clock they hold has the time where they are. But because light from your friend’s clock takes a small amount of time to reach you, you see your friend’s clock a short time ago. It’s the same for them, too. So in other words, you see your friend in the past, and you have therefore gone forward in time!!!
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Think of it like running away from an avalanche – the light has to catch up with you! So the faster you run, the bigger the difference in time you see!
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According to Wikipedia, this happens on the international space station. Every 6 months clocks go 0.007 seconds slower!
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So basically, if you can find a way to travel at nearly the speed of light, you can time travel forwards!
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(If you don’t get this don’t worry! This is general relativity and something you don’t learn unless you do a degree in physics. I don’t understand it. Most adults don’t understand it. My teachers didn’t understand it either! Please ask if you’re still confused!)