Relativity localization question

[swansont]

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?

 

No. You seem determined to interpret a statement in terms of QM when I mention relativity, and relativity when I mention QM. Under that condition, I can't answer your question.

[questionposter]

No. You seem determined to interpret a statement in terms of QM when I mention relativity, and relativity when I mention QM. Under that condition, I can't answer your question.

 

Ok, is how localized a photon is relative?

[swansont]

Ok, is how localized a photon is relative?

 

Too ambiguous. You've asked what localized means, but never defined what you actually mean by it.

 

 

The wavelength in each frame depends on the Doppler shift.

[questionposter]

Too ambiguous. You've asked what localized means, but never defined what you actually mean by it.

 

 

The wavelength in each frame depends on the Doppler shift.

 

By localization I mean how it's probability density spreads out according to it's wavelength, but since nothing is measuring it before it's measured, is it's wavelength before it's measured constant? If we "could" in a way measure it without it counting as a real measurement, would all frames of reference see the same 3 dimensional probability coordinates that are generated by wavelength and the uncertainty principal?

Let's say an electron jumps up 2 orbitals then back down, logically it would emit only a specific frequency of a photon, but you don't know that frequency until you actually measure it, yet that measurement somehow has information as to how localized the photon is before measurement, like wavelength. See the confusion?

[swansont]

By localization I mean how it's probability density spreads out according to it's wavelength, but since nothing is measuring it before it's measured, is it's wavelength before it's measured constant? If we "could" in a way measure it without it counting as a real measurement, would all frames of reference see the same 3 dimensional probability coordinates that are generated by wavelength and the uncertainty principal?

Let's say an electron jumps up 2 orbitals then back down, logically it would emit only a specific frequency of a photon, but you don't know that frequency until you actually measure it, yet that measurement somehow has information as to how localized the photon is before measurement, like wavelength. See the confusion?

 

The probability over all space would still be 1. The radial probability is unchanged, and I expect the angular probability looks just like the Terrell rotation from relativity.

[questionposter]

The probability over all space would still be 1. The radial probability is unchanged, and I expect the angular probability looks just like the Terrell rotation from relativity.

 

Well the probability over all space is one only because of infinite summation properties, like I could say 1/x=0 when x=infinity, but otherwise your saying there are infact properties of localization that aren't "relative" or that stay constant?

Basically, I'm asking in there's different frames of reference, if a photon would 3-dimension-ally be more or less probable to be detected by various frames of reference. Like would the 3 dimensional coordinates for it's most probable location differ depending on the frame of reference? I don't know if it would since it isn't measured yet, and relativity is all about how you measure things.

Edited May 5, 2012 by questionposter

[studiot]

That the total probability is exactly 1 is a fundamental tenet of probability, not to do with infinite series.

 

Take a simple coin toss. The total probability = probability of all possible outcomes = (P_heads+P_tails) = 1

[swansont]

Basically, I'm asking in there's different frames of reference, if a photon would 3-dimension-ally be more or less probable to be detected by various frames of reference.

 

And the answer to that is no. The photon is still there. The overall probability is still 1.

[questionposter]

And the answer to that is no. The photon is still there. The overall probability is still 1.

 

Ok, so regardless of whatever circumstance, a photon has finite 3-dimensional coordinates it will occupy be most probable to be found it. Does that mean I can measure a photon as a radio wave even though it's highest probability only expanded over a few nanometers (which means it was emitted as a gamma-ray from the source).

Edited May 5, 2012 by questionposter

[swansont]

Ok, so regardless of whatever circumstance, a photon has finite 3-dimensional coordinates it will occupy be most probable to be found it. Does that mean I can measure a photon as a radio wave even though it's highest probability only expanded over a few nanometers (which means it was emitted as a gamma-ray from the source).

 

I think you have overconstrained the problem. i.e. you need to demonstrate that the conditional statement is true.

[questionposter]

I think you have overconstrained the problem. i.e. you need to demonstrate that the conditional statement is true.

 

You already said "no" to "is 3-dimensional localization relative?" though. That means an electron drops, say, 30 energy levels and emits a gamma-ray, then even though it will have a small wavelength and occupy a small probable area, if you move away from that photon at 99.99% the speed of light, you would measure it as a radio wave, even though if it were emitted as a radio wave it would have a larger wavelength that would increase the 3-dimensional space it's highest probability expands over, assuming I'm interpreting you correctly when you say "no".

 

So if there's two people next two each other, and I aim two gamma rays at one but they are both moving away from the source at 99.99% the speed of light, only 1 will detect the gamma rays as radio waves because of how localized the gamma-rays are before measurement. Alternatively, if the source emitted two radio waves, both of the people should measure one radio wave or even both to the other person because of how delocalized the radio wave is, and they would measure it having a super-low wavelength.

Edited May 5, 2012 by questionposter

[swansont]

You already said "no" to "is 3-dimensional localization relative?" though.

 

 

I did? Where? I don't see where you asked that question; that phrase only appears in your most recent post. I know that I pointed out that you haven't actually defined what you mean by localized and that a question was ambiguous, so I'm guessing that you have mis-interpreted something.

 

That means an electron drops, say, 30 energy levels and emits a gamma-ray, then even though it will have a small wavelength and occupy a small probable area, if you move away from that photon at 99.99% the speed of light, you would measure it as a radio wave, even though if it were emitted as a radio wave it would have a larger wavelength that would increase the 3-dimensional space it's highest probability expands over, assuming I'm interpreting you correctly when you say "no".

 

A person detecting a radio wave is going to see exactly the same thing if it's a radio wave from the same frame or red-shifted to that wavelength after being emitted from another frame.

 

(technically, electron transitions don't give you gammas, they give x-rays; gammas come from nuclear interactions)

 

 

So if there's two people next two each other, and I aim two gamma rays at one but they are both moving away from the source at 99.99% the speed of light, only 1 will detect the gamma rays as radio waves because of how localized the gamma-rays are before measurement. Alternatively, if the source emitted two radio waves, both of the people should measure one radio wave or even both to the other person because of how delocalized the radio wave is, and they would measure it having a super-low wavelength.

 

I suspect Terrell rotation would address this; I'm not sure but I think the problem is that you would not be able to aim your source well enough to distinguish between the targets.

[questionposter]

I did? Where? I don't see where you asked that question; that phrase only appears in your most recent post. I know that I pointed out that you haven't actually defined what you mean by localized and that a question was ambiguous, so I'm guessing that you have mis-interpreted something.

The type of localization I'm talking about is the type that determines the most probable 4-dimensional coordinates to measure a photon. With gamma rays it's usually a very small area, with radio waves its usually very high.

 

 

 

A person detecting a radio wave is going to see exactly the same thing if it's a radio wave from the same frame or red-shifted to that wavelength after being emitted from another frame.

But that doesn't make sense, measured wavelength is relative, I'm talking about before measurement.

 

I suspect Terrell rotation would address this; I'm not sure but I think the problem is that you would not be able to aim your source well enough to distinguish between the targets.

 

So if I shoot a flashlight at something, it will miss it?

 

 

[between3and26characterslon]

 

But that doesn't make sense, measured wavelength is relative, I'm talking about before measurement.

 

 

Before measurement it is relative also, there is no absolute frame of reference.

[questionposter]

Before measurement it is relative also, there is no absolute frame of reference.

 

But if it's before measurement there's nothing to be a frame of reference from.

[swansont]

But if it's before measurement there's nothing to be a frame of reference from.

 

The frame of reference is always that of the observer.

 

The type of localization I'm talking about is the type that determines the most probable 4-dimensional coordinates to measure a photon. With gamma rays it's usually a very small area, with radio waves its usually very high.

 

You can't tell the difference between a photon that was emitted as one and Doppler-shifted to be the other.

 

 

So if I shoot a flashlight at something, it will miss it?

 

How did we get from a single-photon gamma source to a flashlight?

[questionposter]

The frame of reference is always that of the observer.

But you aren't constantly observing a photon before you have observed it are you?

 

 

 

You can't tell the difference between a photon that was emitted as one and Doppler-shifted to be the other.

I don't know what you mean exactly. So if I shoot a gamma ray and an ultraviolet ray and someone is measuring both photons traveling away from them at 99.99% the speed of light, one should measure one photon having a higher energy.

 

 

 

 

How did we get from a single-photon gamma source to a flashlight?

A flashilight consists of many individual photons, and have you heard of the absolute 0 experiments? People use lasers to shoot at individual atoms in 6 different directions to slow them down.

Edited May 6, 2012 by questionposter

[swansont]

But you aren't constantly observing a photon before you have observed it are you?

 

That wasn't the question. The question was what defines a frame.

 

 

I don't know what you mean exactly. So if I shoot a gamma ray and an ultraviolet ray and someone is measuring both photons traveling away from them at 99.99% the speed of light, one should measure one photon having a higher energy.

 

That wasn't the scenario under discussion. We were talking about whether there was a difference between something emitted as a radio wave and something shifted to be a radio wave because of relative motion.

 

A flashilight consists of many individual photons, and have you heard of the absolute 0 experiments? People use lasers to shoot at individual atoms in 6 different directions to slow them down.

 

 

We weren't discussing that. We weren't discussing anything like that.

 

Yes, I've heard of laser cooling. I've been doing it for the last ~20 years. They aren't "absolute 0" experiments, and I see no relevance to anything you've brought up in this thread.

 

I would be exceedingly helpful if you would stick to one topic, instead of shifting gears all the time.

[questionposter]

I don't see how you aren't understanding me considering I've tried almost as many different ways to explain it as I have made posts in this topic, you must just be skimming through my posts.

I don't understand your photon inaccuracy scenario. If you've been working with lasers so long, your obviously aware we have the capability to aim a photon to a high degree of accuracy, especially gamma-rays since they are used for cancer treatment. I also never said that the red-shifted radio wave and the emitted radio wave would have the same energy or wavelength.

So if I shoot a gamma ray at someone who is moving away from me at 99.99% the speed of light, they will measure it as a radio wave, but the gamma-ray will still be very localized and occupy mostly a small area right? So even though it's a gamma ray, because of their frame of reference, they should measure a radio wave that was very localized. Seeing as how they can't measure it before the measurement, I don't see how localized something is before measurement can be relative.

Edited May 6, 2012 by questionposter

[swansont]

I don't see how you aren't understanding me considering I've tried almost as many different ways to explain it as I have made posts in this topic, you must just be skimming through my posts.

 

Your rephrasing changes the context of the question.

 

I don't understand your photon inaccuracy scenario. If you've been working with lasers so long, your obviously aware we have the capability to aim a photon to a high degree of accuracy, especially gamma-rays since they are used for cancer treatment.

 

Gammas and x-rays (i.e. high-energy photons) are actually very hard to focus.

 

 

I also never said that the red-shifted radio wave and the emitted radio wave would have the same energy or wavelength.

So if I shoot a gamma ray at someone who is moving away from me at 99.99% the speed of light, they will measure it as a radio wave, but the gamma-ray will still be very localized and occupy mostly a small area right? So even though it's a gamma ray, because of their frame of reference, they should measure a radio wave that was very localized. Seeing as how they can't measure it before the measurement, I don't see how localized something is before measurement can be relative.

 

No, that's the point I've been trying to make. If you are in the frame where it is a radio wave, it's a radio wave. Of the two frames, it only has a small wavelength in the frame in which it was emitted. The observer for whom it is a radio wave can tell no difference between it and a radio wave emitted in his frame.

[questionposter]

Your rephrasing changes the context of the question.

Well I'm constantly asking a different question so you can better see what I'm trying to get at since my previous questions aren't well interpreted.

 

 

 

Gammas and x-rays (i.e. high-energy photons) are actually very hard to focus.

Well I can see how the uncertainty principal would come into play, but we have lasers that can shoot at individual atoms and get rid of cancer, it's hard to think I couldn't hit a whole person with just 1.

 

 

 

 

No, that's the point I've been trying to make. If you are in the frame where it is a radio wave, it's a radio wave. Of the two frames, it only has a small wavelength in the frame in which it was emitted. The observer for whom it is a radio wave can tell no difference between it and a radio wave emitted in his frame.

But isn't it only a frame of a radio-wave after you measure it? What is it before measurement? You can't constantly observe it before you observe it, so how do you tell how localized it was before your measurement? How do you have a frame of reference of something before you measure it?

Edited May 7, 2012 by questionposter

[swansont]

Well I'm constantly asking a different question so you can better see what I'm trying to get at since my previous questions aren't well interpreted.

 

It's not helping when you aren't asking a question in a different way, rather you're jumping around to a new topic.

 

 

Well I can see how the uncertainty principal would come into play, but we have lasers that can shoot at individual atoms and get rid of cancer, it's hard to think I couldn't hit a whole person with just 1.

 

It's not the uncertainty principle, and no, I don't think we do. I'd like to see your evidence of this. I can see targeting a small cluster of cells perhaps, or maybe even one cell, but not individual atoms. Not as a spatial target, in the context of aiming. I can see targeting in terms of a resonance that interacted with a specific target and not "bystander" atoms, but that's not the same thing.

 

 

But isn't it only a frame of a radio-wave after you measure it? What is it before measurement? You can't constantly observe it before you observe it, so how do you tell how localized it was before your measurement? How do you have a frame of reference of something before you measure it?

 

A frame of reference is a coordinate system.

 

If you take the position that a photon can't be localized before measurement, then it doesn't matter what the wavelength is. Thus, the question is moot. However, in the context of doing multiple measurements, you could measure localization by looking at where the photons interacted with a detector. The area of this is going to be distributed over an area that scales, somehow, with the wavelength. Thus, if you know you have a photon with some wavelength, you expect a certain result. That's how you know: you have a well-tested theory that tells you what to expect.

[between3and26characterslon]

Well I'm constantly asking a different question so you can better see what I'm trying to get at since my previous questions aren't well interpreted.

 

Well I can see how the uncertainty principal would come into play, but we have lasers that can shoot at individual atoms and get rid of cancer, it's hard to think I couldn't hit a whole person with just 1.

 

 

But isn't it only a frame of a radio-wave after you measure it? What is it before measurement? You can't constantly observe it before you observe it, so how do you tell how localized it was before your measurement? How do you have a frame of reference of something before you measure it?

 

"Argumentum ad tedium"

 

I'm guessing that localisation is frame dependant also.

 

 

If you have a coordinate system that is moving at constant speed and is not accelerating it behaves as though it is at rest and is called inertial frame. This is the principle of relativity. More succinctly; the laws of physics in a coordiate system with constant motion (no acceleration or rotation) are no less simple than a coordinate system at rest.

 

If you have a photon source in an inertial frame and this source is at rest relative to this inertial frame then an emitted photon will have a specific frequency within this frame, let's call it x. It has freq x when emitted, freq x throughout its journey (ignoring universal expansion for now) and if you have a receiver which is also at rest in the inertial frame it will record freq x.

 

If you have a receiver rapidly travelling towards the photon source it will measure freq > x and if you have a receiver rapidly travelling away from the source it will record freq < x. Both of these new receivers are moving in your original frame but are stationary in their own inertial frames.

 

So if your receiver is moving towards the source then not only will it measure freq > x but it is true to say that relative to its coordinate system the photon was emitted with freq > x and had freq > x throughout its entire journey.

 

I would conclude therefore that localisation is also frame dependant.

 

 

 

It seems to me that you are thinking the photon has an absolute frequency which changes depending on how you are moving relative to it and what you are asking is what is its "proper" frequency. This would only be true only if there was and absolute frame of reference... but there isn't.

 

The frequency with which a photon is emitted, travels or is received is relative to the frame you are in when these phenomina occur.

[questionposter]

It's not the uncertainty principle, and no, I don't think we do. I'd like to see your evidence of this. I can see targeting a small cluster of cells perhaps, or maybe even one cell, but not individual atoms. Not as a spatial target, in the context of aiming. I can see targeting in terms of a resonance that interacted with a specific target and not "bystander" atoms, but that's not the same thing.

Well there's this on laser cooling,

http://en.wikipedia....i/Laser_cooling as well as footage of an individual atom http://www.scienceda...80222095358.htm

And how is it not the uncertainty principal with aiming it considering

I suppose it could be more likely that its a group of atoms, but it's hard to think such a dangerous thing would be used in cancer treatment if it wasn't accurate.

 

 

A frame of reference is a coordinate system.

 

If you take the position that a photon can't be localized before measurement, then it doesn't matter what the wavelength is. Thus, the question is moot. However, in the context of doing multiple measurements, you could measure localization by looking at where the photons interacted with a detector. The area of this is going to be distributed over an area that scales, somehow, with the wavelength. Thus, if you know you have a photon with some wavelength, you expect a certain result. That's how you know: you have a well-tested theory that tells you what to expect.

Well photons aren't infinitely delocalized before you observe them, they have to have some kind of parameters of the 3-dimensional space they occupy before measurement otherwise we would never measure them or measure them instantaneously. I want to know what those parameters are.

Edited May 7, 2012 by questionposter

[swansont]

Well there's this on laser cooling,

http://en.wikipedia....i/Laser_cooling as well as footage of an individual atom http://www.scienceda...80222095358.htm

 

There's WHAT on laser cooling? I'm not going to chase down every red herring you throw at me. If you can't point to the relevant part, don't bother. You don't physically target individual atoms. Being able to cool or image an atom does not mean you hit it with each photon you sent at it.

 

And how is it not the uncertainty principal with aiming it considering

I suppose it could be more likely that its a group of atoms, but it's hard to think such a dangerous thing would be used in cancer treatment if it wasn't accurate.

 

Again, I am not going to waste time watching a video when I have no confidence it is relevant. What I said was that the uncertainty principle is not the concern with FOCUSING x-rays or gamma rays. You changed the subject, AGAIN. (and yet accuse me of only skimming your posts)

 

 

Well photons aren't infinitely delocalized before you observe them, they have to have some kind of parameters of the 3-dimensional space they occupy before measurement otherwise we would never measure them or measure them instantaneously. I want to know what those parameters are.

Sigh. How many posts back did I say wavelength? Why are you still asking the question?

 

You still have not explained why you think you would detect the photon instantaneously if you don't know where it is, or faster if it has a longer wavelength. You are proceeding as if it were true, and yet haven't established that it is. That's a problem.