Light

[ikester7579]

Yep, just as I thought.

 

[Jet Black]

so do you understand light a bit better now?

 

[Bushido216]

I think he was trying to make a side-ways arguement for the "light slows down" theory.


If not, I apologize for the inclination.

 

[Phred]

Erm.. maybe I don't quite understand what you mean. First of all, 0.999999 percent the speed of light is almost 1% the speed of light. Do you mean 99.999% the speed of light? If so, I do not see how you could reach Proxima Centauri in 16 hours. It is located 4.2 lightyears from the sun, hence, it takes light 4.2 years to get there. So if you travelled at almost the speed of light you would get there in just above 4.2 years. The same applies to travelling to the center of the milky way. But maybe I just don't understand you correctly?

My bad, I meant .9999999c.

And, while observed from outside 4.2 years will indeed go by. But from your frame of reference the journey will only take 16 hours. To you, the universe will seem to speed up. To an observer on Earth you will seem to slow down.

 

[Jet Black]

My bad, I meant .9999999c.

And, while observed from outside 4.2 years will indeed go by. But from your frame of reference the journey will only take 16 hours. To you, the universe will seem to speed up. To an observer on Earth you will seem to slow down.

yus, time dilation rules .


just to add to your reply there.... if you travelled at c, you would feel like you got there instantly, wheras everyone else would think you took 4 years. for more on this look up the Lorentz transforms. these are a consequence of the speed of light being constant for any local observer.

 

[Mike Flynn]

My bad, I meant .9999999c.

And, while observed from outside 4.2 years will indeed go by. But from your frame of reference the journey will only take 16 hours. To you, the universe will seem to speed up. To an observer on Earth you will seem to slow down.

I think you've got it...but just to add a bit more:

Its a common misconception people have that the observed 'clocks' only *seem* to register different times (a kind of observational effect). Of course, the time difference is very real. At the heart of this principle is a concept in physics called symmetry.

In General relativity, all frames of reference are completely symmetric, even accelerating ones. In physics, this means that all of the laws of physics in each frame of reference are the *same* (hence 'symmetry'...sameness). Because we observe time dilation, symmetry tells us that we will also observe other effects accordingly (length contraction, mass increase, relativistic momentum, etc). All the transformations taken together ensure that the same laws of physics will be observed for any observer in any frame of reference, regardless of their speed or acceleration.

Is that confusing enough? We havn't even talked about the quantum formulation of light yet.