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As JP says, it's really impossible to say. However, there may be a clue in that, as far as we know, light, and all other forms of electromagnetic radiation, do not decay over time. The photons that were released at the birth of our Universe just keep on trucking. That suggests they are "timeless".
I'd argue this one with you. Photons released at the birth of our universe can be absorbed and they are also stretched out by the expansion of the universe even if they don't spontaneously decay. If a photon is there one minute and absorbed the next, what does that say? Or if a photon is red-shifted over millions of years, what does that mean? Mostly, I just don't like the word timeless being applied to photons because it can be taken out of context easily. If you understand well what's going on, as you do, then you can use it without being confused. If you don't understand special relativity well, then you might be tempted to interpret the word timeless to mean that if photons carried clocks, those clocks would stop. I think, and what I believe the theory is saying, is that our human concepts of time as measurable intervals between events doesn't even exist for photons. We can't even define a concept of time for them, so why bother trying to explain their viewpoint in our terms?
Quote from: JP on 02/06/2011 04:03:24I'd argue this one with you. Photons released at the birth of our universe can be absorbed and they are also stretched out by the expansion of the universe even if they don't spontaneously decay. If a photon is there one minute and absorbed the next, what does that say? Or if a photon is red-shifted over millions of years, what does that mean? Mostly, I just don't like the word timeless being applied to photons because it can be taken out of context easily. If you understand well what's going on, as you do, then you can use it without being confused. If you don't understand special relativity well, then you might be tempted to interpret the word timeless to mean that if photons carried clocks, those clocks would stop. I think, and what I believe the theory is saying, is that our human concepts of time as measurable intervals between events doesn't even exist for photons. We can't even define a concept of time for them, so why bother trying to explain their viewpoint in our terms?I knew you would My argument probably hinges on whether or not there are other things that don't spontaneously decay. I'm not sure if there are or not.
I agree that you have a good point. I just think the word "timeless" has connotations that could confuse a lay person.
This is a big point of confusion in special relativity. The theory says that if you have two observers with clocks, and one moves very fast with respect to the other, if they compare their clocks, the fast observer's clock appears to be running slow. The faster he/she goes, the slower the moving clock appears to go, tending to infinite length intervals of time per second of the stationary clock as the observer gets closer an closer to the speed of light.This seems to indicate that light itself, which always moves at light speed, would have a clock that ran infinitely slow, so it wouldn't experience time. But there's a major flaw in this reasoning. From the point of view of the equations, they apply only to objects with mass that can never reach the speed of light. The theory was developed by treating light in a special way, so the equations don't apply to what light "sees." (Also important: seeing and experiencing requires that we have eyes, which have to have mass to work, and a brain, which has to have mass to work. Photons can't have either nor can anything moving at the speed of light.)
Well, I have a simple definition of photon being a clock of sorts. You just need to do your measurement locally to see that it always will be/give you a 'constant'. The rest is no measurements, it's you assuming that red shift etc gives you a relation that you by Lorentz transformations can relate to the way radiation treat you. And it's correct of course, but if you fail to see that your measurements and transformations only comes to be conceptually as you try to translate it into one coherent definition for radiation you miss the point. Relativity is very simple if you use the local point of view to define it, and there are no misunderstanding of it then. In a way that confusion tells us more of the way we grow up and learn to treat reality, than about what reality really is. Light have only one beat 'c' as you can measure. When you measure a red shift from the traveler, that light still have only one invariant speed in your measurements.Try that way of looking at it and the pieces will fall in place.
You're doing what I defined as wrong, comparing frames of reference there, Mr. Data. If you define if from locality instead, as I, then all experiments you can do have one same invariant speed of light. It has to do with your definitions of 'reality'. If you define 'reality' from what you see conceptually then 'relativistic effects' becomes confusing and reality becomes complicated. If you define it locally you will find that this 'invariant speed' of light is what defines and explains 'relativistic phenomena'. The invariant 'clock' as I call lights constant, is what defines those measurements you do, and there is no way you ever will get another beat from a direct measurement.
A lot of the confusion about locality raises from 'frames of reference'. A often used example for 'proving' that light have different 'speeds' is by using clocks and rulers to define a speed inside a accelerating frame, as your spacecraft accelerating. If you define two points in the direction of your propulsion inside that ship, 'A' and 'B', separated by a distance. Then you put clocks that are synchronized at one common point at those locations. Then you measure lights speed relative those two points/clocks, finding that when you compare your measurements 'A' against 'B' they will give you a different speed for that light depending on the direction you measured it. That's a 'conceptual' comparison as I see it. But it has a simple explanation in that gravity will blue and red shift light, and also, later when comparing clocks, seem to slow 'time' depending on gravitational potential. But, in both measurements they will show you the same invariant 'speed' of light relative that clock you measured it from. The confusion raises when you compare those two 'frames of reference' to each other. And as shown by out 'atomic clocks' on that table. When one is moved to the floor the same thing happens, one clock will go 'slower' than the other.So a 'frame of reference' is in reality a abstract thing, very hard to pinpoint. I define it as each point of SpaceTime will have a own 'frame of reference' myself.
A photonic universe?If you by that mean that you doubt my definition of 'locality' you must also doubt lights invariant speed in a vacuum?
No, I don't need it. I use a constant for defining the 'clock'. And I'm sorry if you can't see my definitions. I try to keep them simple, but if you don't get it I may be failing in that.A photonic universe is a very strange idea And as I said, I use a constant, defining it as Einstein did, of a unvarying speed in, and from, all frames possible. If you don't see it I can only draw the conclusion that you have other definitions of it?
I'm sorry Mr Data. You will need to look up the definition of lights speed in a vacuum to see, then you better check Einsteins 1905 paper over SR, and from there go to GR. In the 1905 paper he defined light as being a 'constant' and from there he built Special Relativity. That is the 'constant' I'm using and that one always hold true locally. That you from comparing another frame of reference to yours, presuming that they all are the same 'locally', as you find a Lorentz transformation needed to equalize your observations, actually build on that constant. Without it there can be no Lorentz transformations to define as we then would have a variable 'speed' and 'time'. And that was what I was wondering about, I've seen some try to define it that way, but if doing so you're no longer building on SR and GR.
I'm not discussing a photons 'frame of reference' at all? You just don't seem to read what I write here? I define light as a constant, then I define what a frame of reference is, all to explain why I'm defining 'locality' as the proper perspective for understanding relativity. As for your question? There is no 'frame of reference' from a photons perspective. If you mean the 'clock' I'm discussing, then that can be defined as lights invariant speed in a vacuum.=='Frames of reference' build on lights speed in a vacuum too. That's why they exist, and it has taken me some pondering to understand them properly. You can see them as something that exist up to 'c'. At 'c' we have no proper definitions for them, as that is a limit of our understanding. It's a 'singularity' of sorts, in that we can't define what happens pass that limit, other as a theoretical guess. FTL and taychons may be called theories, but as they have no experimental evidence I know of, I would call them hypothesis's myself.