Does light exist outside of time ?

boatdeck
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Trying to imagine what the world looks like traveling at relativistic speeds of course has a noble history, vis a vis Swiss trams etc. etc. I get the thing about passing clocks at speed and staying young by going really fast (and slowing down again). I apologise if this perhaps rather obvious thought experiment has been done to death, but what would it be like to travel on a beam of light itself, by definition AT the speed of light ? What might one see ? What will happen to time ? It's this latter point which intrigues. Is time dilation such that the traveller's time frame actually freezes relative to the rest of the universe ? Does time stand still ? Does light exist (from its own perspective) outside of time ? Do all light wave travellers travel instantaneously to the end of time, the universe and “everything”, observing the rest of us slow coaches fizzle out to cold dark dust in an instant ?

From a Newbie waiting to be shot down ! - though don't be too harsh – I'm a veteran of Mr Tompkins and can claim at least an “A” level physics and maths.
 
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boatdeck said:
From a Newbie waiting to be shot down
Bang! ...sssss... plop. :wink:

boatdeck, Traveling at the speed of light is simply impossible. So, speculating about what it would be like to do so has no connection with reality. You can approach c but never attain it.
 
Bill_K said:
Bang! ...sssss... plop. :wink:

boatdeck, Traveling at the speed of light is simply impossible. So, speculating about what it would be like to do so has no connection with reality. You can approach c but never attain it.

Mmm. Yes I picked up on that point. With respect, LIGHT can travel at C, I kind of mean (in a just partly metaphysical way) what might it be "like" to be that beam of light ? What might the nature of it's experience be, if it had the capacity to observe it's surroundings ?
 
boatdeck said:
Mmm. Yes I picked up on that point. With respect, LIGHT can travel at C, I kind of mean (in a just partly metaphysical way) what might it be "like" to be that beam of light ? What might the nature of it's experience be, if it had the capacity to observe it's surroundings ?

From the FAQ at the top of this forum: https://www.physicsforums.com/showthread.php?t=511170
 
OK - so does that inform my question ? -= light travels at C and only ever travels at that speed, and cannot be stationary. Fair enough. I'm trying to finesse my Q. - is light "frozen" in time ? Does time have any meaning for a beam of light ?
 
boatdeck said:
OK - so does that inform my question ? -= light travels at C and only ever travels at that speed, and cannot be stationary. Fair enough. I'm trying to finesse my Q. - is light "frozen" in time ? Does time have any meaning for a beam of light ?

Time has no meaning for a beam of light.
Asking how light "might experience" time by applying the formulas for bodies with non-zero rest mass moving at speeds less than c to zero-rest-mass light moving at c leads only to absurdities.
 
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