# Wormholes, Time Travel and the Universe

In order to explain wormholes and time travel, we must first get to grips with the actual universe. Currently, the general opinion is that the universe is expanding and not infinite, and that wormholes are a strong possibility.

Think of the universe as a big rubber sheet with objects on it, such as galaxies, planets and stars. This sheet is constantly expanding from no particular point and it sinks when affected by gravity - so a star would sit in a pit on the rubber, affecting both space and any nearby objects. Now imagine that the gravity is so strong that it tears that rubber sheet and appears on the other side - an alternate universe some may say. This 'other side' may be the explaination for why there is so much matter here and almost no antimatter, but that's another story altogether... Back to the hole though. Anything near the hole would be sucked into it (the hole has gravity) and also come out of the other side. Doing so would move the objects being sucked through at around the speed of light (Stephen Hawking has an equation for that and it's huge). As we all know, once you are near the speed of light you go forward in time, and when you exceed it you go back...however, the only reason you move at the speed of light is because all of your mass is converted into energy in order to fit the conservation of mass in the other universe. But hey, you can travel back in time, right? Wrong. Only in the other universe, because the hole would destroy itself also and shut faster than light, creating an alternate 'you' in the original universe and plonking them back on Earth, only to continue a vicious cycle...

Note by A Former Brilliant Member
6 years, 1 month ago

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