No way

Science fiction has always been interested in the idea of going back in time to fix a mistake or find out more about the future. Scientists are still not sure if it is possible to travel into the past, but they are sure that it is possible to travel into the future. A wormhole or a DeLorean are not needed.

Einstein’s theory of special relativity has a part called time dilation that makes time travel possible in the real world. Einstein found that, contrary to what most people think, time slows down as you move faster through space.

Einstein rethought space as a part of his theory. He came up with the word “spacetime” when he put together the one dimension of time and the three dimensions of space. Einstein thought that space was curved and pliable, and that it could form gravitational dips around masses that pull other objects in, like how a bowling ball in the middle of a trampoline makes any smaller object on the trampoline slide toward the centre. The old way of thinking about space was that it was a flat, rigid place where all the things in the universe lived.

The faster something moves, the closer it is to the middle of the dip. The gravitational dip of the Earth is at the centre of the Earth, where the force of gravity is strongest. Einstein’s theory says that time moves more slowly the closer an object is to the centre of the Earth. This is because time moves more slowly the faster you move through space.

This happens with GPS satellites, which orbit 20,200 km above the Earth’s surface. Because of time dilation, the clocks on these satellites add an average of 38 microseconds each day. Even though it doesn’t seem like much, GPS satellites use their own clocks to make sure they are in the right place around the world. Running 38 microseconds too fast would cause a location error of almost 10 kilometres, and if the difference in timing wasn’t fixed every day, the error would get worse every day.

In the movie Interstellar, Matthew McConaughey and his team arrive on a planet with a strong gravitational field caused by a black hole. This is a more dramatic example of how time slows down. Because the black hole’s gravity is so strong, time moves very slowly for the crew on the planet. One hour on the planet’s surface is equal to seven years on Earth. So, when the team gets back to Earth, Matthew McConaughey’s daughter is an old woman and he looks the same age as he did before.

So, why hasn’t humanity been able to advance so quickly through time? It all comes down to speed to figure out the answer. Either humans would have to send a time traveller into space at close to the speed of light (about 1 billion km/h) or they would have to use the strong gravitational acceleration of black holes. With the technology we have now, people can only go a few microseconds into the future.