Light speed questions!

[themos]

The thing that most interests me is (if it's really true) that time slows down for a person travelling close to the speed of light, therefore it doesn't feel like such a long time to them to travel a certain distance.

There's the two ways of looking at it:

1) You look at someone going really fast trying to get from A-B, a spatial distance that, to you, is 10 light-years. You see their clock going slow so you think it will take THEM less time than 10ly/speed.

2) You are the person going fast. Your clock goes at the normal rate but the A-B distance has shrunk so you think it will take less time than 10ly/speed.

The reducing factors are the same in both cases.

[gareththegeek]

Have you ever read 'The Forever War' by Joe Haldeman? Excellent book which involves interstellar travel and the effects of Time Dilation.

I think the problem is that time passes slowly for you in the space ship but passes normally for everyone else so by the time you got home years would have passed.

[themos]

The answer to that is for everyone to go off and see the universe.

[sgazer]

Have you ever read 'The Forever War' by Joe Haldeman? Excellent book which involves interstellar travel and the effects of Time Dilation.

I think the problem is that time passes slowly for you in the space ship but passes normally for everyone else so by the time you got home years would have passed.

oh yes, it would definately have to be a 1 way trip, unless of course you wanted to see Earth in the future. Also, if you are travelling 90% the speed of light, in a couple of hundred earth years, possibly only 1 year for you on the ship, you might get another ship overtaking you at 95% the speed of light, due to knew Earth technology!

[calibos]

Have you ever read 'The Forever War' by Joe Haldeman? Excellent book which involves interstellar travel and the effects of Time Dilation.

I think the problem is that time passes slowly for you in the space ship but passes normally for everyone else so by the time you got home years would have passed.

My brother was just telling me about that book. Must borrow it.

Don't know anything about the book other than what you said above and that involves an interstellar war, but it sounds like there could be story threads in it analgous to you getting a punch in the face from someone and saying WTF was that for!! ie. Alien race attacks your planet. You set off on a revenge mission. The desire for revenge is still fresh in your mind because upon arrival at the aliens planet from your perspective the attack by these aliens on your planet happened only a few weeks/months ago. You blow the Rubbish out of them and they don't know why you attacked them. Turns out it was the equivelent of the Syrians bombing Cairo because of an attack on Syria by Pharoah Rameses the first in 3000BC They don't even have historial records of ever attacking your planet!!

Mind Bending stuff.

Intersellar travel at relativistic speeds would be great as long as you can bring along all your friends and family because any trip over 50 odd light years or more means that by the time your few weeks trip is over and you get back to earth, everyone you ever knew or loved would be dead. Would 'Single', 'only child' and 'orphan' be pre-requisites for a job on an interstellar spacecraft?

It is mad when you think that when a given photon left the Andromeda galaxy, humans hadn't evolved here on earth but from the photons perspective it left the Andromeda Galaxy a blink of an eye ago.

[brianb]

Intersellar travel at relativistic speeds would be great as long as you can bring along all your friends and family because any trip over 50 odd light years or more means that by the time your few weeks trip is over and you get back to earth, everyone you ever knew or loved would be dead. Would 'Single', 'only child' and 'orphan' be pre-requisites for a job on an interstellar spacecraft?

Why would you want to come back?

This is a serious question. The Pilgrim Fathers in the 17th century voluntarily embarked on a trip across the ocean on the understanding it would be outward bound only.