Travelling at speed

[Richie Stan]

I think I recall watching something about astronauts that spend a long time in space, travelling at very high speeds, have travelled in time (I cant remember if it was forwards or backward)?. It had something to do with time changing the faster you went.

I think they proved it by making two atomic clocks one stayed on earth the other went to space, when it came back the time on the clocks was different.

Is this true or did I dream it?

[Loosehead]

Perfectly true, 2 cesium clocks where syncronized and one was flown around the world in a Jumbo jet. Time passed more slowly for the one in the jet. I believe the time dilatiion matched Einstiens predictions.

Astronauts orbiting the Earth are travelling at thousands of MPH and hence they are aging slower that the rest of us. But at the speeds concerned it's negligible.

[Richie Stan]

So the astronauts spent more time in space than we did waiting of them to return?

[boobesque]

no its the other way round. from our perspective they were up there for say 10 hours but to the astronauts they were there for 9hrs 59.9 minutes

[Richie Stan]

That makes my brain hurt. I going to lie down.

[Richie Stan]

Is this just a difference in the clocks or a real, time travel?

Say you had two plants totally identical, with totally identical environments/food, every thing the same. One goes up and round the earth very fast, many times the other stays at home. Would the plant that goes to space be younger i.e. smaller, than the one left at home?

[Loosehead]

Yes it's real time dilation, if I where to accelerate to close to the speed of light away from the earth and then come straight back, time would have hardly moved for me but you would be very old indeed.

[Richie Stan]

Would it have to be away from the earth, why not just round the earth?

[Loosehead]

yes that would work too.

[Richie Stan]

Hard to put into words, harder still to achieve. If some kind of computer program was made using some kind of light relay, (where the program was travelling at the speed of light).

Then a problem, that takes years to work out could be sent on the relay (travelling at the speed of light) and take years to calculate but to us it would take seconds.

Is that some kind of theory?

[fo3nix]

Richie: the theory made by Einstein and others is called Special Relativity. There are many great books on it; one such as Spacetime Physics by Taylor and Wheeler.

[Lil' help]

Lol so there is some truth in the superman cartoons, when superman would fly around the world to turn back time =)

[mibn2cweus]

The record for time travel to date is probably held by Cosmonaut Sergei Avdeyev who spent a total of 748 days on the Russian space station Mir during three separate missions. Because Mir was moving relative to Earth, it was also a time machine. Avdeyev is 0.02 seconds younger than he would have been had he never traveled in space.

[fo3nix]

Lil' help: not really, no. If you travel faster and faster it won't reverse time on the planet. Even if somehow you break the laws of physics and go faster than the speed of light (which many seem to think means you'll go back in time), the equations just point to you entering imaginary time, whatever that is.