Another Brain Teaser.

[Kyajae]

After the 1/0 debate (and thanks to all who contributed), something else that I've never fathomed.

How does time slow down when you approach the speed of light?

Anyone with a simple(ish) answer?

[malvolio]

Well it's all relative, isn't it...

[AtW]

As you get closer to the speed of light it makes in effect light not move, so you go blind - close your eyes and you will feel it is forever after just few short years.

HTH

threaded.

[wendigo100]

After the 1/0 debate (and thanks to all who contributed), something else that I've never fathomed.

How does time slow down when you approach the speed of light?

Anyone with a simple(ish) answer?

As I understand it, time starts slowing down at any velocity.

However, the traveller himself doesn't perceive it. The observer perceives it in the traveller.

I never quite understood, what with relativity and stuff, how you define which is the traveller and which is the observer anyway.

[threaded]

As I understand it, time starts slowing down at any velocity.

However, the traveller himself doesn't perceive it. The observer perceives it in the traveller.

I never quite understood, what with relativity and stuff, how you define which is the traveller and which is the observer anyway.

Forget the velocity stuff, that requires a frame of reference, it's all to do with accelerations in space-time.
To cut a long story short the traveller is the one being accelerated.

HTH

[wendigo100]

Forget the velocity stuff, that requires a frame of reference, it's all to do with accelerations in space-time.
To cut a long story short the traveller is the one being accelerated.

HTH

Is that why Linford Christie still looks quite young?

[threaded]

Is that why Linford Christie still looks quite young?

I have his problem you know, when I'm out cycling, they look at me in my lycra shorts with a mixture of admiration and envy. Some of the leering women make you feel all dirty.

[The Lone Gunman]

Look for the bouncing ball explanation.

Never mind, found one. try http://answers.yahoo.com/question/in...3091536AAImNcf

[EternalOptimist]

The bouncing ball explanations is, er, balls. All it proves is that the ball travels at different speeds dependant upon the observer. What you need is something that cannot change speed,ie, light.

If you use light instead of a ball, the speed must be constant for both observers, therefore the only other variable must be different - time. Here is the thought experiment that I learned at uni. Followed by an interesting paradox.

Imagine a spacecraft flying past the earth very fast. As it passes Pluto a passenger switches on a light, as it passes Neptune the light hits the wall opposite the passenger. As far as the passenger is concerned the light has travelled 20 feet in n units of time.

To you on the earth, the light has travelled a million miles in n units of time.

But light travels at the same speed to all observers everywhere, so the conclusion is that the passengers time and your time must be different and the only reason can be the fact that the passenger is travelling very fast.

Travel fast = time goes slower.


An interesting paradox.

Nothing can travel faster than the speed of light. Imagine a searchlight beaming up at the clouds. Flick the searchlight and the bright circle whizzes across the clouds. It must be possible to either flick the searchlight fast enough, or move the clouds high enough, to make the spot move FTL.

[gingerjedi]

I have his problem you know, when I'm out cycling, they look at me in my lycra shorts with a mixture of admiration and envy. Some of the leering women make you feel all dirty.

But doesn't your mass increase the faster you go? ...an unwanted side effect.

This would explain why it gets very hard to pedal past the 35mph mark!