Question about the speed of light and relativity

[Carnivroar]

If light always travels at the speed of light,

and at the speed of light, time stops --

does this mean that light is eternal?

In other words, if you were a particle of light, you would exist forever?

 

[Disconnected]

Well, if light doesn't follow the rules of having to travel below the speed of light, then it's likely to say that they don't experience time dilation. If they did, we would literally see every photon everywhere at once.

 

[mathman]

If light always travels at the speed of light,

and at the speed of light, time stops --

does this mean that light is eternal?

In other words, if you were a particle of light, you would exist forever?

Yes, as long as it didn't interact with anything. The cosmic microwave background consists of photons from the big bang (after about 300,000 years, when the universe cooled down enough so the photons would stop interacting). The long wavelength results from the expansion of the universe since then.

 

[ZealScience]

If light always travels at the speed of light,

and at the speed of light, time stops --

does this mean that light is eternal?

In other words, if you were a particle of light, you would exist forever?

What do you mean by exist forever? Time dilation of relativity means time measurement is dilated i.e. what a man travels near the speed of light would be extremely long via the measurement of a resting man. But there's no point in eternal, eternal is quite like a classical sense. If you can live 90 years, whatever the speed you are travelling, you would live 90 years. Only in classical Newton's "time", there would be "eternality".

 

[Carnivroar]

What do you mean by exist forever? Time dilation of relativity means time measurement is dilated i.e. what a man travels near the speed of light would be extremely long via the measurement of a resting man. But there's no point in eternal, eternal is quite like a classical sense. If you can live 90 years, whatever the speed you are travelling, you would live 90 years. Only in classical Newton's "time", there would be "eternality".

I see what you mean. I'm having trouble swallowing the idea of eternity myself.

Let me see if I can rephrase this. Suppose light had consciousness and it was moving at the speed of light (where time supposedly stops?), would it then experience existence forever as long as it's speed remained undisturbed? It would never "age"?

Anyways looks like I found a thread on precisely this, https://www.physicsforums.com/showthread.php?t=235132, I'm going to read it now.