Is Time Experienced by Photons at the Speed of Light?

[.Scott]

OK. Let's do this one more time.
It doesn't make sense to say "approaching the speed of light" without offering a frame of reference.
In this case, I was trying to describe a speed relative to Earth that was so close to the speed of light that it would be at least 0.99999999c relative to anything with mass: pot bellies, LHC particles, cosmic rays, anything.

And just to be clear, it would not matter if it turned out that there was something else in the universe that turned out to be going the same speed as my reference frame. It would invalidate my description of the speed as being "more than 0.9999999c relative to anything", but it would not invalidate its use in context.

It was not my intention to use terms that could be interpreted in such a variety of ways. I thought there was sufficient context to make my intent clear.

 

[YoungPhysicist]

cosmic rays close to the speed of light

Sorry for the unrelated content, but is that the OMG particle?

https://en.m.wikipedia.org/wiki/Oh-My-God_particle

 

[.Scott]

Sorry for the unrelated content, but is that the OMG particle?

https://en.m.wikipedia.org/wiki/Oh-My-God_particle

Yes. And it's the reason I picked it in response to the LHC example.

 

[m4r35n357]

In this case, I was trying to describe a speed relative to Earth that was so close to the speed of light that it would be at least 0.99999999c relative to anything with mass: pot bellies, LHC particles, cosmic rays, anything.

Your insistence here indicates that you do not fully understand what relative motion means and how to specify it. "Relative to anything with mass" means nothing whatsoever (for example, is the mass in question moving WRT you or not?). Did you understand my previous comment?

 

[.Scott]

Your insistence here indicates that you do not fully understand what relative motion means and how to specify it. "Relative to anything with mass" means nothing whatsoever (for example, is the mass in question moving WRT you or not?). Did you understand my previous comment?

Yes I do understand. In the original context, I was referring to speeds relative to the observer that were so close to c that they would be close to c no matter what massive reference frame was selected.
My point was not to discount the relativity of velocities but to emphasize the extremeness of the reference frame I was describing.

 

[m4r35n357]

Yes I do understand. In the original context, I was referring to speeds relative to the observer that were so close to c that they would be close to c no matter what massive reference frame was selected.
My point was not to discount the relativity of velocities but to emphasize the extremeness of the reference frame I was describing.

At this point I must give up. There is no such thing as an "extreme" (inertial) reference frame, they are all equivalent. Your point is consistently obscured by your reluctance to adopt the language we are all trying to get you to use.

 

[.Scott]

At this point I must give up. There is no such thing as an "extreme" (inertial) reference frame, they are all equivalent. Your point is consistently obscured by your reluctance to adopt the language we are all trying to get you to use.

It can only be extreme relative to another reference frame. I never said otherwise.
And in the original context, that type of extremeness was important because we wanted to consider how the rest of the universe would look from such an extreme reference frame.

I also get that just because you are traveling at 0.99999999999999c relative to Earth, you are still no closer to the speed of light than you were before you left Earth.

That doesn't stop me from considering reference frames where the speed of our galaxy (relative to that frame) appears to be very close to the speed of light.

I think the issue here is that I am willing to use that as a possible window into questions related to "how a photon sees the universe" - admitting that the photon, by my calculation or anyone else's, has zero time to "see" anything.

 

[SiennaTheGr8]

Tangentially related is the GZK limit.

 

[timmdeeg]

That doesn't stop me from considering reference frames where the speed of our galaxy (relative to that frame) appears to be very close to the speed of light.

And you can always imagine an observer who’s speed is even closer to the speed of light. But you can never imagine an obsrever who measures the speed of light less than c in his frame. And that’s the reason that the question “how a photon sees the universe” doesn’t make any sense.

 

[Ibix]

That doesn't stop me from considering reference frames where the speed of our galaxy (relative to that frame) appears to be very close to the speed of light.

Of course you can. But in such frames, just like the rest frame of the galaxy, the speed of light is 3×10⁸m/s. So you aren't really any closer to knowing what the perspective of light is. Fundamentally, that's because the concept doesn't make sense, certainly not as an extension of standard inertial frames.

 

[.Scott]

And you can always imagine an observer who’s speed is even closer to the speed of light. But you can never imagine an observer who measures the speed of light less than c in his frame. And that’s the reason that the question “how a photon sees the universe” doesn’t make any sense.

That's interesting. In the process of refuting that the photon reference frame exists, without intending to, you just presumed something about that frame. Specifically, you have presumed that in such a frame, the speed of light would appear to be less than c. I know you didn't mean to do that - but since you've brought it up, I would have presumed that even in a photon's reference frame, the speed of light would remain to be c. Since there's no stop-watch in that frame, who's to say otherwise.

 

[Ibix]

I would have presumed that even in a photon's reference frame, the speed of light would remain to be c.

Exactly. And it would have to be zero also - or otherwise what do you mean by "photon's reference frame" other than its rest frame?

 

[.Scott]

Exactly. And it would have to be zero also - or otherwise what do you mean by "photon's reference frame" other than its rest frame?

What doesn't bother me about that is that from a photon's reference frame, there is no time and therefore, there is no velocity. Velocity is simply something that cannot be observed from that reference frame.

 

[timmdeeg]

What doesn't bother me about that is that from a photon's reference frame, there is no time and therefore, there is no velocity. Velocity is simply something that cannot be observed from that reference frame.

If doesn’t bother you if at the end of the day you agree that a photon’s reference frame does not exist.

 

[Nugatory]

I would have presumed that even in a photon's reference frame, the speed of light would remain to be c.

What doesn't bother me about that is that from a photon's reference frame, there is no time and therefore, there is no velocity. Velocity is simply something that cannot be observed from that reference frame.

OK, this thread has gone off the deep end... it is closed.