People may find Stephen Hawking's ideas of alien encounters humorous, but it'll be silly not to give it any possibility that intelligent life exists outside our boundaries. There's a chance, even if a small one.
But what recently captured my attention was Hawking's latest musings about time travel, wormholes, and speed of light. I think I finally understand how one can travel to the future on a time machine. But first a couple of axioms:
- The faster you travel, the slower the time passes for you. If one could reach the speed of light, time would stop, but no one can reach that speed.
- Travelling to the past is not possible because of the potential paradox. For example if one travels to the past and kills an ancestor, then the person would not have existed to travel to the past and kill the ancestor, and so on.
With those basic rules in mind, here's how one can travel to the future. If the person gets onboard a train that travels really fast, time will slow down for that person, but the rest of the world will be on normal time. Now if the train reaches near-light speeds, each second for that person could be the equivalent of years on the outside. If the train returns to the station after 10 minutes (as measured by the person onboard), the world would be centuries beyond the time when the person had left.
The person is only 10 minutes older but centuries have passed on the outside and that's how the person finds himself in the future. There's just one problem. Since travelling to the past isn't possible, the person is now stuck in the future and can not return to the original time to tell the tale. In other words time travel to the future is a one-way ticket. Something to think about if you ever get the chance to jump aboard that train 🙂