questionposter Posted April 28, 2012 Share Posted April 28, 2012 If I have two different frames of reference, one of which would observe a photon at a very energy and one at a very low energy if the photon got to either one, but both frames of reference were equidistant from the photon source, the low energy photon would be much more delocialized, so wouldn't the observer who's frame of reference possibly observe a low energy photon before the high energy photon could be measured? Link to comment Share on other sites More sharing options...
studiot Posted April 28, 2012 Share Posted April 28, 2012 Under what circumstances do you think your scenario couls come about? How do you think the perceived differences in energy would show up? Hint energy is proportional to what property of a photon, given its speed is the same for all observers? Link to comment Share on other sites More sharing options...
questionposter Posted April 28, 2012 Author Share Posted April 28, 2012 Under what circumstances do you think your scenario couls come about? How do you think the perceived differences in energy would show up? Hint energy is proportional to what property of a photon, given its speed is the same for all observers? Don't know, it's a hypothetical, but it would help illustrate how localization works if it does actually work like that. Link to comment Share on other sites More sharing options...
swansont Posted April 29, 2012 Share Posted April 29, 2012 In relativity frames of reference are coordinate systems. They can move at some speed relative to the other. Saying that frames are equidistant from anything makes no sense. Link to comment Share on other sites More sharing options...
questionposter Posted April 29, 2012 Author Share Posted April 29, 2012 (edited) In relativity frames of reference are coordinate systems. They can move at some speed relative to the other. Saying that frames are equidistant from anything makes no sense. Ok, let's say its the same photon that two possible frames of reference could observe. One would observe the photon having a high energy, and the other would observing the other having a low energy. Wouldn't the one observing it having a low energy measure it first because relative to them the photon would be more delocalized and occupy a much greater probable area? A radio-wave extends over many meters, but a gamma ray is only around a few nanometers, so...one could expect to see high energy gamma rays from a source but then not observe them because another frame of reference observes them as being delocalized and then measures them first due to the greater are occupied? Edited April 29, 2012 by questionposter Link to comment Share on other sites More sharing options...
studiot Posted April 29, 2012 Share Posted April 29, 2012 So how do you think a perceived energy difference would show up? What would be different measured in each frame? Frames extend throught the universe so what do you mean about measuring the same photon in different frames? You still haven't provided sufficient information to describe/define the situation. When you do you might see what others are trying to point out. Link to comment Share on other sites More sharing options...
questionposter Posted April 29, 2012 Author Share Posted April 29, 2012 (edited) So how do you think a perceived energy difference would show up? What would be different measured in each frame? Frames extend throught the universe so what do you mean about measuring the same photon in different frames? You still haven't provided sufficient information to describe/define the situation. When you do you might see what others are trying to point out. Let's say for a brief moment one frame of reference moves really fast towards the photon source and another really fast away from the electron source. This would increase/decrease the relative frequency, but therefore the relative localization? Edited April 29, 2012 by questionposter Link to comment Share on other sites More sharing options...
swansont Posted April 29, 2012 Share Posted April 29, 2012 You still measure the photon(s) in whatever detector you have. If it hits, it hits. I don't know how to interpret "measure it first" — they're different frames. Simultaneity is not applicable. Link to comment Share on other sites More sharing options...
questionposter Posted April 30, 2012 Author Share Posted April 30, 2012 (edited) You still measure the photon(s) in whatever detector you have. If it hits, it hits. I don't know how to interpret "measure it first" — they're different frames. Simultaneity is not applicable. But with what I'm seeing with combining relativity and localization is if I move away from a photon really fast, it has low energy and should therefore be delocalized, but if another source is moving towards that photon, to them it should have higher energy and therefore be more localized, so localization depends on the frame of reference and the person moving away could expect to see the photon first before the person moving towards it because the photon is so delocalized at such low energies? Edited April 30, 2012 by questionposter Link to comment Share on other sites More sharing options...
swansont Posted April 30, 2012 Share Posted April 30, 2012 A photon is not delocalized when you detect it. I still don't know what you mean by "see it first". Link to comment Share on other sites More sharing options...
questionposter Posted April 30, 2012 Author Share Posted April 30, 2012 (edited) A photon is not delocalized when you detect it. I still don't know what you mean by "see it first". S photon isn't delocalized when you detect it because when you detect it it's just a point, but prior to that it is delocalized by some amount. When I mean "see it first", I literally mean see it first, because to one frame of reference shouldn't a photon comming from a source have a low relative energy? And shouldn't that energy determine how localized it is? And if it didn't work this way before, how do you actually know how localized the photon is prior to measurement? Wouldn't it sort of break relativity if a photon had the same probability to all frames of reference? Edited April 30, 2012 by questionposter Link to comment Share on other sites More sharing options...
swansont Posted April 30, 2012 Share Posted April 30, 2012 A photon that isn't localized hasn't been detected, i.e. it hasn't been seen. You can't have both. Link to comment Share on other sites More sharing options...
questionposter Posted April 30, 2012 Author Share Posted April 30, 2012 (edited) A photon that isn't localized hasn't been detected, i.e. it hasn't been seen. You can't have both. So, how can we guess how localized something is then? If a radio-wave is emitted and we know it's a radio-wave, don't we "know" its delocalized? But couldn't the energy that a source emits be relative? How does a specific frame of reference determine the "real" localization of an unobserved photon? It can't be infinitely delocalized because if it was, we would instantaneously measure it. Edited May 1, 2012 by questionposter Link to comment Share on other sites More sharing options...
swansont Posted May 1, 2012 Share Posted May 1, 2012 How does a specific frame of reference determine the "real" localization of an unobserved photon? It doesn't. It can't be infinitely delocalized because if it was, we would instantaneously measure it. I don't see how that follows. You can't have a probability of 1 of being at more than one location Link to comment Share on other sites More sharing options...
questionposter Posted May 1, 2012 Author Share Posted May 1, 2012 (edited) It doesn't. I don't see how that follows. You can't have a probability of 1 of being at more than one location Well what actually determines how localized a photon is then? Wouldn't it break relativity if from every frame of reference a photon has the same localization? Edited May 1, 2012 by questionposter Link to comment Share on other sites More sharing options...
swansont Posted May 1, 2012 Share Posted May 1, 2012 Well what actually determines how localized a photon is then? It depends on the situation and how you are defining localization. Often it's represented by the wavelength. Wouldn't it break relativity if from every frame of reference a photon has the same localization? I don't see how this question follows, logically, from what I've said. I never claimed that every photon has the same "localization" Link to comment Share on other sites More sharing options...
questionposter Posted May 1, 2012 Author Share Posted May 1, 2012 It depends on the situation and how you are defining localization. Often it's represented by the wavelength. The wavelength "measured" is relative, but since there isn't measurement before that, is there a finite localization that a photon is while its traveling? I don't see how this question follows, logically, from what I've said. I never claimed that every photon has the same "localization" I know you didn't say "every photon", but I said every frame of reference not every photon. Link to comment Share on other sites More sharing options...
swansont Posted May 2, 2012 Share Posted May 2, 2012 The wavelength "measured" is relative, but since there isn't measurement before that, is there a finite localization that a photon is while its traveling? I know you didn't say "every photon", but I said every frame of reference not every photon. Yes, I misread that. I still don't see why the localization is an issue in anything. What principle is violated? Link to comment Share on other sites More sharing options...
questionposter Posted May 2, 2012 Author Share Posted May 2, 2012 (edited) Yes, I misread that. I still don't see why the localization is an issue in anything. What principle is violated? How is the energy relative but the localization isn't? Relativistically speaking, how is localization determined before measurement? Is the lcoalization depends on energy, but energy is relative, yet you can't measure a photon before it's been observed, so what's it's relative localization if I move, say 10% the speed of light away from a photon? Is the localization of a single photon the same from all frames of reference if those frames could actually measure it? Edited May 2, 2012 by questionposter Link to comment Share on other sites More sharing options...
swansont Posted May 2, 2012 Share Posted May 2, 2012 I ask again, what principle do you think is being violated by a change in the wavelength? Link to comment Share on other sites More sharing options...
questionposter Posted May 2, 2012 Author Share Posted May 2, 2012 (edited) I ask again, what principle do you think is being violated by a change in the wavelength? Change? No, it's the lack of change. If a photon get's emitted from a source, is the probability of detecting it the same from all frames of reference since energy can only be known after measurement? Does relativity just not apply to things when they exist in an unmeasured state? Edited May 2, 2012 by questionposter Link to comment Share on other sites More sharing options...
swansont Posted May 3, 2012 Share Posted May 3, 2012 Change? No, it's the lack of change. If a photon get's emitted from a source, is the probability of detecting it the same from all frames of reference since energy can only be known after measurement? Does relativity just not apply to things when they exist in an unmeasured state? The wavelength does change. Link to comment Share on other sites More sharing options...
questionposter Posted May 3, 2012 Author Share Posted May 3, 2012 (edited) The wavelength does change. How does it change without anyone measuring it? What determined the probable wavelength? Or is the energy emitted from a source sort of universal? Edited May 3, 2012 by questionposter Link to comment Share on other sites More sharing options...
swansont Posted May 3, 2012 Share Posted May 3, 2012 I will rephrase. When you measure it, you will find the wavelength has changed. It is determined by the Doppler shift. Link to comment Share on other sites More sharing options...
questionposter Posted May 3, 2012 Author Share Posted May 3, 2012 (edited) I will rephrase. When you measure it, you will find the wavelength has changed. It is determined by the Doppler shift. So in other words, the energy it starts out with would be the same from all frames of reference if it could be measured while doing that, but only the actual measurement is different to different frames of reference? Edited May 3, 2012 by questionposter Link to comment Share on other sites More sharing options...
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