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Thread: the doppler effect energy problem

  1. #1 the doppler effect energy problem 
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    hell a little problem, imagine a star very far away travelling very fast away from us and a photon is emitted from it in our direction, the photon will be red-shifted and according to the relationship E=hf if the frequency is decreased there is an energy loss. Where does this energy go?

    and vice versa if it is moving towards us the frequency of light is increased therefore energy is gained where does this energy comes from?
    please reply
    thankyou


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  3. #2 Re: the doppler effect energy problem 
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    Quote Originally Posted by rhysboi1991
    hell a little problem, imagine a star very far away travelling very fast away from us and a photon is emitted from it in our direction, the photon will be red-shifted and according to the relationship E=hf if the frequency is decreased there is an energy loss. Where does this energy go?

    and vice versa if it is moving towards us the frequency of light is increased therefore energy is gained where does this energy comes from?
    please reply
    thankyou
    En3ergy is dependent on the rest frame of the observer. In your example there is no energy gained or lost, so no problem at all.


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    The thing is that the photon isn't red-shifted; only the portion of the light-wave that is travelling towards you is. The part of the wave that is moving away from you (which you can never see) is blue-shifted.

    I think it is better to think of a photon as an event that causes an electo-magnetic wave in the same way that a stone dropped into a pool of water causes a ripple. A photon can be any event from an electron changing its energy state to nuclear collisions in the same way that a stone can be anything from a grain of sand to a boulder of rock.
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  5. #4  
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    Quote Originally Posted by himnextdoor
    The thing is that the photon isn't red-shifted; only the portion of the light-wave that is travelling towards you is. The part of the wave that is moving away from you (which you can never see) is blue-shifted.

    I think it is better to think of a photon as an event that causes an electo-magnetic wave in the same way that a stone dropped into a pool of water causes a ripple. A photon can be any event from an electron changing its energy state to nuclear collisions in the same way that a stone can be anything from a grain of sand to a boulder of rock.
    No. It is indeed the photon that is red-shifted. Electromagnetic waves are just a lot of photons. You cannot spit a photon into two parts.

    You are thinking of photons in the wrong way.
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  6. #5  
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    How big can a photon be?

    Is it not the case that each photon-producing event causes an electro-magnetic wave to propogate through space?

    One photon-producing event, one photon, one wave?

    If a source of photons emitted one photon every second, how precisely would a photon detector need to be placed in order to count them? Wouldn't a detector placed at the side of it detect them also?

    Sorry about all the question marks.

    It seems unfeasible that every electro-magnetic source emits an infinite number of photons all the time.
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  7. #6  
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    No, if one photon is produced, it will be produced with a direction, and a detector placed to the side will not detect it. (This is done regularly during testing of any number of QM effects.)
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    Suppose you have a installation as with the double split system. There is a screen with two slits and one photon goes thrue both slits at the same time. Suppose you,re looking through one of these slits as a window and someone else is looking through the other slit. In astronomy the screen can be replaced to two telescopes. So the one next to you can see the same photon.

    With the screen and the two slits you can remove the screen with the slits. You'll see one lightspot on the other screen (well in theory it will be to short to see it I guess). Now make the distance longer and the lightspot grows and becomes less intense at the same time. But it,s still about one quantum.

    Now look to the light with a telescope where would the "lost energy" be ? No event is exclusive for one viewer even if it is about one quantum.
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  9. #8  
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    Quote Originally Posted by Ghrasp
    Suppose you have a installation as with the double split system. There is a screen with two slits and one photon goes thrue both slits at the same time. Suppose you,re looking through one of these slits as a window and someone else is looking through the other slit. In astronomy the screen can be replaced to two telescopes. So the one next to you can see the same photon.
    No, only one telescope will see the photon. This the same as the experiment where you put a detector at each slit of the screen to measure the passage of the photons. Each photon will be measured as passing through only one slit and the interference pattern is no longer formed. Remove the detectors and the pattern returns.
    "Men are apt to mistake the strength of their feelings for the strength of their argument.
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  10. #9  
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    Most events we see involve a multitude of quanta. You can lower the multitude and come to quantumscale. The way you imagine it if an event happens on quantumscale (only one quantum) it could be seen by only one observer in the universe and if that observer has two eyes he could only see it with one eye (?)

    I thought the essence and mystery of the experiment is that it even works with one quantum (from the perspective of the activator/source).

    The wave nature of light causes the light waves passing through both slits to interfere, creating an interference pattern of bright and dark bands on the screen. However, at the screen, the light is always found to be absorbed as though it were made of discrete particles, called photons
    With this quote from wikipedia, I think you forget the "as though" part in the last sentence where I would underline that.
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    I fully support Wiki, but I wouldn't take it's word as law.

    You're failing to grasp the weirdness of QM. If there are detectors at each slit, then one one will register a single photon with equal distributions. If there is are detectors behind the slits, they will register each photon, one at a time, but in a pattern that shows wave-like interference patterns. In neither case will a detector off to the side register anything. At the quantum level, nothing is distinctly a particle or a wave and there is no "as though". It really is that weird.
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  12. #11  
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    Quote Originally Posted by himnextdoor
    How big can a photon be?

    Is it not the case that each photon-producing event causes an electro-magnetic wave to propogate through space?

    One photon-producing event, one photon, one wave?

    .
    NO.

    An electromagnetic wave consists of a great many photons.
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  13. #12  
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    Quote Originally Posted by DrRocket
    NO. An electromagnetic wave consists of a great many photons.
    I strongly beg to differ. Single photons cannot have a frequency, wavelength, a phase or even an amplitude, which are all well known properties of light, it just makes no sense. The wave model of light is much more logical and correct. The photon concept arose during the irrational era of quantum mechanics, and should be avoided. Lets face it, light is a wave: How can photons explain interference patterns? How can they explain refraction? How can they explain standing waves? How can they explain phase change upon reflection? How can they explain polarization? This list goes on and on. Light MUST be a wave. We made an error by changing our model because we misunderstood one thing: the photoelectric effect. We call light a particle to suit one experiment, which then contradicts HUNDREDS of earlier experiments. Even worse, some people think that light is both a particle and a wave, and this is just delirious.
    "Doubt is the origin of Wisdom" - Rene Descartes
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    Okay, bear with me for a moment.

    The middle star in Orion's belt is called Alnilam. Its radius is 44 times that of the sun and it is over 1300 lightyears from earth. It is the 30th brightest object in the sky and can easily be seen with the naked eye.

    Imagine that Alnilam is at the centre of a circle with a radius of 1300 lightyears and that the earth lies at a point on that circle. Dividing the diameter of the earth into the circumference of the circle and expressing as an arc tells us that the earth represents an angle of 2.163 x 10 raised to the power of -7 seconds of a degree. This equates roughly to 11.5 metres at the surface of the star.

    Assuming that the photons are emitted perpendicular to the surface of the star, it would appear that all the light that arrives at the earth's surface from Alnilam originated from a circle with a radius of 5.75 metres. That is a lot of dispersion.

    Given that the light has to penetrate the atmosphere, shouldn't photons from Alnilam be rare at the earth's surface? How come it doesn't blink as I move around?

    And if was twice as far away, I think I would still see it.
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  15. #14  
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    Quote Originally Posted by himnextdoor
    Okay, bear with me for a moment.

    The middle star in Orion's belt is called Alnilam. Its radius is 44 times that of the sun and it is over 1300 lightyears from earth. It is the 30th brightest object in the sky and can easily be seen with the naked eye.

    Imagine that Alnilam is at the centre of a circle with a radius of 1300 lightyears and that the earth lies at a point on that circle. Dividing the diameter of the earth into the circumference of the circle and expressing as an arc tells us that the earth represents an angle of 2.163 x 10 raised to the power of -7 seconds of a degree. This equates roughly to 11.5 metres at the surface of the star.

    Assuming that the photons are emitted perpendicular to the surface of the star, it would appear that all the light that arrives at the earth's surface from Alnilam originated from a circle with a radius of 5.75 metres. That is a lot of dispersion.

    Given that the light has to penetrate the atmosphere, shouldn't photons from Alnilam be rare at the earth's surface? How come it doesn't blink as I move around?

    And if was twice as far away, I think I would still see it.
    What you describe is the inverse square law. This is exactly how the brightness of stars is defined. The intensity of light (= incident rate of photons) is proportional to the square of the distance between source and detector. This is equivalent to the fact that the intensity is proportional to the area penetrated by the electromagnetic wave front.
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  16. #15  
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    You're failing to grasp the weirdness of QM. If there are detectors at each slit, then one one will register a single photon with equal distributions. If there is are detectors behind the slits, they will register each photon, one at a time, but in a pattern that shows wave-like interference patterns. In neither case will a detector off to the side register anything. At the quantum level, nothing is distinctly a particle or a wave and there is no "as though". It really is that weird.
    I dont see it as weird more like mystery. Way I see it is not as different as when poales stand in a lake and waves come through. You would expect the poales to cut the waves but they aren,t cut behind the poalles, only locally at the poales (screen) they come through it as a whole again. Look at the patterns as the ways to solve it.

    But anyway then you are still implying my one eye sees different events then my other eye ? Because foton emission is often regarded the emission of one foton corresponding with one event on quantum scale. When such an event happens only one person could see it ? That really is weird (and I cannot believe it I,m sorry).

    I would never use the word faillure though regarding annyones attempts to understand things.
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    @Ghrasp:
    Yes. If a single photon were created in some event, only one person would be able to see it, assuming anyone saw it at all. And yes, each of your eyes is receiving different photons.

    Imagine shining a laser in a dark, dust free room. If you aim it at someone's left eye (without blinding them somehow), neither their right eye, nor anyone else's eyes will see that laser at all.


    @Waveman:
    A single photon does indeed have a wavelength whether or not it makes sense to you. Electrons, protons, neutrons and baseballs all have wavelengths. For something as big as a baseball though, the amplitude of the wave is so small that there is no way to measure it, but there is no hard cut off point between that and subatomic particles.

    A single photon also has a position and a velocity. Pretty much the definition of a particle. It's both.
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  18. #17  
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    Imagine shining a laser in a dark, dust free room. If you aim it at someone's left eye (without blinding them somehow), neither their right eye, nor anyone else's eyes will see that laser at all.
    That depends how big the laser is or how far the eyes are apart off course. Even with a laser if you would projekt it on a screen the lightspot gets a little bigger if the screen is placed at bigger distance, there is always some divergency. (if you would let it go through a glasscable the divergency increases related to a lower C.

    Yes. If a single photon were created in some event, only one person would be able to see it, assuming anyone saw it at all. And yes, each of your eyes is receiving different photons.
    So the reality you experience is of a complete private and autistic character ? Because that,s the conclusion, everyone experiences a different reality.

    I can,t live with that no matter how much consensus there would be to that. If theory or fysiscs says so then something must be wrong (or incomplete, limp) with theory. It would mean a complete autistic world because everyone would live in a complete private world.
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    If a photon carries momentum then it must also have mass. The mass may be tiny, immeasurable, but it is not insignificant and could not be ignored or treated as negligible.

    Light energy can be detected at every point in space. This forces us to conclude that there is at least one photon at every point in space and since I can see many sources of light from one point (I see humdreds of stars above me tonight) that would indicate that there are many photons occupying the same point. ???

    Therefore, the universe is packed full of photons.

    In fact, there is no space; just photons.

    Oh! But that would mean that some photons are occupying the same space and everybody knows that two masses cannot occupy the same space.

    So, quick question; how can an emitted photons pass through space without interacting with other photons in space? What happens when, as it surely must, two photons are involved in a head-on collision?

    The other thing is, if the universe is filled with photons, as experimentation would support, then we have an 'ether' and one could come to the conclusion that matter is made of photons interacting with each other.

    It may also explain the missing mass which accounts for the Universe's rate of expansion. No need for dark-matter or black-holes.

    What are the properties of a photon?
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  20. #19  
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    @Ghrasp, let me qualify that as "shining an idealized laser". Anyway, yes, everyone experiences the universe in a non-identical way. General relativity says that both time and space are local concepts. However, in the everyday world, every event that produces photons produces an unimaginably large number of them in pretty much every direction and there are numerous nearly identical copies of each, and time and space are fairly flat on the everyday scale, so even though everyone experiences something slightly different, it's close enough that you can't tell the difference.

    @himnextdoor, No, light has momentum, but not mass. The full equation for momentum () is . is 0 for photons, but isn't.
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    Would it be fair to say that:

    A photon to an electromagnetic wave is as a water molecule is to a wave travelling accross the surface of a pool.

    Similar in the sense that each molecule of water represents a 'packet of energy' at a single point on the wave that can be measured for vectorable components; velocity, direction, characteristics that could be plotted over time to show frequency, amplitude and, if we know the mass of a water-molecule, energy and momentum.

    Two aspects that appear to be missing from the water-molecule model are 'spin' and the constant 'c' for the speed of light but the water-molecule can be above or below the x-axis of the wave which gives us a plus and minus component that can be substituted for spin and the constant force of gravity, which is the same for all the water-molecules, could substitute for the speed of light.

    Is there anything in the photon model that can't be explained in the water-molecule model?

    I ask because I'd like to understand the implications of the differences between the two models as far as the topology and the dispersal of waves, divergence, is concerned in such a way that I can explain QM to a child and I want my analogies to be accurate.

    For instance, in the water model, there is space between the water molecules and one could not measure any properties at those points; the 'sensing' equipment needs to be in 'contact' with a water-molecule in order to generate any meaningful data. However, one might still obtain a reading that indicates an 'odd component' in the energy distribution of energy.

    Is this the case with photons? Are photons seperated by space and are they divergent; does the space between them increase?

    The topology of the surface of the water-wave is shaped by the molecules at the water-air boundary. If one were able to freeze the wave in time and represent its profile on an oscilloscope (roughly a sine-wave) and magnify the image to a molecular scale, the shape of the molecules would give the appearance of a high-frequency component superimposed on the low-frequency 'energy-wave'. This imposes a 'quantisation limit'; the size of the molecule limits the accuracy to which the shape of the wave, at any given point in time, can be plotted.

    Is this the case with photons? If photons have a shape then at some level of magnification, the profile of an electr-magnetic wave would be shaped by the photons, again, giving the impression that there is a high-frequency component superimposed on a low-frequency fundamental and again, imposes a 'quantisation limit'.

    Here's the thing though: If we measure the same water-wave at some point later in its journey, it has the same high-frequency component as it did before; the distance between the water-molecules that are carrying the wave's energy stays the same. This is in contrast with the photon model; the photons diverge over time which suggests that the surface topology of an electro-magnetic wave dissolves into points that become increasingly distant from each other.

    This leads naturally to the conclusion that if an elecro-magnetic wave detector were positioned at a sufficient distance from a radio transmitter, photons, from that source, could pass close by that detector and no electro-magnetic wave would be detected.

    Can this be so? Is it posible that an electro-magnetic wave moves through space gradually dissolving into increasingly distant points?

    I'm used to thinking of a light-wave as a membrane as opposed to buck-shot. 8)
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  22. #21  
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    @Ghrasp, let me qualify that as "shining an idealized laser".
    I hope you can accept that I would qualify it as non-realistic or a laser that is not seen. Because when it enters water, or the eye- lens the beam would show (for a short trajektory) a higher divergency.


    everyone experiences the universe in a non-identical way.
    If you say a foton is the result of an event (or what conects observer and the observed) and one foton can be seen/experienced only by one particular observer then those observers would not experience the universe different they all would experience different events and thus different universes. Even if these experiences would have similarities.

    That,s why I have a problem with it. I have no problem with everyone experiencing reality different. If there is a reality it must be a shared reality also..somehow.
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    Quote Originally Posted by Ghrasp
    @Ghrasp, let me qualify that as "shining an idealized laser".
    I hope you can accept that I would qualify it as non-realistic or a laser that is not seen. Because when it enters water, or the eye- lens the beam would show (for a short trajektory) a higher divergency.
    Luckily there's no water in the situation he defined. In addition, by the time it reaches the lens, it still proves his point. Consider each eye to be an observing particle (if you're looking for a more appropriate model). Lastly, lasers only diverge due to diffraction from the laser unit - else they're all theoretically 'idealized'.

    @himnextdoor has got it pretty much bang-on with his comparison to mechanical waves. You can also compare it to AC current.
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  24. #23  
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    "Theoretically idealized" ? I hope you understand the meaning (and consecquence) of these two words in combination. In science you need to show it also.

    Luckily there's no water in the situation he defined.
    But there is air, less dense but not vacuum. Vacuum is theory and if somewhere for some distance and time would be nothing that doesn,t mean vacuum it just means that timespace is expanded, distances are bigger etc.

    What I know is that if light hits a lens but also flat glass, the beam changes it,s convergency/divergency as it enters and as it comes out ; twice.

    But also in space if the objekt a laser is directed to is smaller then the beam diameter the light would convert to it (as light "bows to it). So it can even convert But then the "lines" also don't run mathematically parallel ánd offcourse in deepspace the beam is hardly visible. If you see a beam of light you see the dust in the air, moist, molecules. With very low density a beam of light gets more and more invisible.

    If you are at sea swimming and a wave comes on the beach different people share the same wave, not each his own waves. Thats what I mean with shared reality from different perspective. These waves also can be counted and therefor quantified (so Im not arguing with that necessarily).
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  25. #24  
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    Quote Originally Posted by Waveman28
    Quote Originally Posted by DrRocket
    NO. An electromagnetic wave consists of a great many photons.
    I strongly beg to differ. Single photons cannot have a frequency, wavelength, a phase or even an amplitude, which are all well known properties of light, it just makes no sense. The wave model of light is much more logical and correct. The photon concept arose during the irrational era of quantum mechanics, and should be avoided. Lets face it, light is a wave: How can photons explain interference patterns? How can they explain refraction? How can they explain standing waves? How can they explain phase change upon reflection? How can they explain polarization? This list goes on and on. Light MUST be a wave. We made an error by changing our model because we misunderstood one thing: the photoelectric effect. We call light a particle to suit one experiment, which then contradicts HUNDREDS of earlier experiments. Even worse, some people think that light is both a particle and a wave, and this is just delirious.
    Wrong.

    Completely, totally, utterly wrong.

    Not even close.

    You are certainly free to entertain whatever wacko notions of physics please your pshcye. But they are still wromg.

    Wrong in being in deisagreemenet with a mountain of experimental data. Wrong in being in disagreement with well-established theories, specifically quantum electrodynamics which is one of the most successful physical theories ever.
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    Quote Originally Posted by lawrencejob
    Quote Originally Posted by Ghrasp
    @Ghrasp, let me qualify that as "shining an idealized laser".
    I hope you can accept that I would qualify it as non-realistic or a laser that is not seen. Because when it enters water, or the eye- lens the beam would show (for a short trajektory) a higher divergency.
    Luckily there's no water in the situation he defined. In addition, by the time it reaches the lens, it still proves his point. Consider each eye to be an observing particle (if you're looking for a more appropriate model). Lastly, lasers only diverge due to diffraction from the laser unit - else they're all theoretically 'idealized'.

    @himnextdoor has got it pretty much bang-on with his comparison to mechanical waves. You can also compare it to AC current.
    The thing is, laser operation can be explained much more satisfactorily by wave theory; a model which explains real phenomena without having to resort to inventing new dimensions.

    Physics isn't hard, God's plan is simple

    Besides, any model has to be robust enough to stand up to being tested. Isn't that just good science as opposed to 'wacky notions'. If you remember, it was Einstein's 'wacky notion' that led to his theory of relativity.

    P.S. Loving the discussion.
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  27. #26  
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    Quote Originally Posted by MagiMaster
    @Waveman:
    A single photon does indeed have a wavelength whether or not it makes sense to you. Electrons, protons, neutrons and baseballs all have wavelengths. For something as big as a baseball though, the amplitude of the wave is so small that there is no way to measure it, but there is no hard cut off point between that and subatomic particles.

    A single photon also has a position and a velocity. Pretty much the definition of a particle. It's both.
    If a single photon has a wavelength, what does this wavelength represent? A wavelength is defined as the distance over which a wave repeats itself. How the HELL can a particle have a wavelength? Where the hell has logic and common sense gone in science, it seems as though everything is being replaced by mathematics and equations, which do nothing to explain what is really going on. An electron has a wavelength because it is a wave, not a particle.

    A wave can have a position and a velocity too, what is your point? And how can light be 2 completely different things at once? THINK about it, dont just repeat what somebody else has told you, or quote something you have read somewhere, that is meaningless.

    Quote Originally Posted by DrRocket
    Wrong.

    Completely, totally, utterly wrong.

    Not even close.

    You are certainly free to entertain whatever wacko notions of physics please your pshcye. But they are still wromg.

    Wrong in being in deisagreemenet with a mountain of experimental data. Wrong in being in disagreement with well-established theories, specifically quantum electrodynamics which is one of the most successful physical theories ever.
    Care to explain for once in your life? I explained why light cannot be a particle, and it seems you have nothing to counter with.
    "Doubt is the origin of Wisdom" - Rene Descartes
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    @Ghrasp: An idealized laser would emit a perfect, 1-dimensional line of photons. Such a device is, in fact, impossible to build as far as I know, but such a beam could only be observed by a single observer. A real laser emits a very narrow cone of photons.

    Anyway, if an event occured that only emitted a single photon (and no other forms of radiation), only one observer could possibly observe that event. Few if any real events emit only a single photon. When you shine a flashlight at a couple of people, each person is seeing different photons, but they're all very similar. The every day world is made of the averages of an unimaginale number of tiny events. Each event is different, but the average isn't. Just because you and I can't see the exact same photon doesn't mean we're living in different universes. Two people in the ocean can be hit by the same wave, but it'll be by different molecules of water within that wave.

    @Waveman: I'm sorry if you can't comprehend how a wave and a particle might not be two different things, or how our every day notions of "wave" and "particle" are simply insufficient to describe a photon. As to what's waving, there are two possibilities that I know of. Either it's a probability wave, that is the change in the probability can be described as a waveform, or the particle is waving through dimensions we can't see directly, which is one of the main points of string theory.

    Also, I'm not simply repeating things I hear. I listen to what's said, then think things through to see if they make sense. I also know that I don't know everything, and I know that things at scales I'm not personally familiar with don't have to conform to expectations based on the everyday world.

    BTW, a mechanical wave cannot have a single position. Instead it has a range of positions. Also, an electron has mass and a photon doesn't.
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  29. #28  
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    Quote Originally Posted by Waveman28
    Care to explain for once in your life? I explained why light cannot be a particle, and it seems you have nothing to counter with.
    Read any physics book that covers the rudiments of quantum mechanics.

    A photon absolutely has a frequency, and it is determined by its energy.



    Frequency of a single photon is a quantum phenomena.

    A classical electromagnetic wave, of a single frequency, is the result of a mutitude of photons of that frequency, as with a monochrmatic LED, or in the case of a coherent wave, a laser.

    Here is a link to a Wiki article on the double experiment. Pay attention to the series of pictures labeled "Electron buildup over time". There you see the classical wave interference pattern being developed by individual particles. It works exactly the same way with photons. Photons are particles.

    Photons are particles, quantum particles. They are not little marbles.

    Go read Feynman's book QED. It will explain in simple terms the nature of photons. They are particles.

    I can always counter yor with simple physics. That is no problem.

    The only problem is getting through to you, which I think is impossible. However, it is probably worthwhile to point out that your post is nonsense for the benefit of innocent lurkers.
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    Any device that can receive radio waves whether they be photons or electro-magnetic waves is actually doing nothing more than sampling space and transducing an energy value over time.

    The receiving apparatus has to interact with the energy it is detecting, converting one form of energy into another.

    Sticking with the photon model:

    Suppose a radio-tranmitter was broadcasting a signal at a constant frequency of one-megahertz and a radio is receiving the signal via a dipole ariel. Reception occurs when photons interact with the eletrons in the ariel and causes a current to flow that is proportion to the modulation of the radio-signal.

    However, the interaction between the photons and the electrons of the ariel are a random process. The situation could occur where two photons conveying identical energy/wavelength/spin characteristics interact with two different electrons in two completely different ways. The two photons would make different contribution to the signal current. In fact, this would be the case for all the photons; the signal detected by the radio would be random, just white-noise.

    Does that make sense?

    Doesn't the fact that this doesn't happen go to prove that 'photons' are not real?

    In no way do I intend to detract from the usefullness of the photon-model but I am not sure that it is more accurate to say that 'energy comes as particles' than it is to say, 'it is as if energy comes in particles'.
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    As a footnote to that;

    How can the ariel distinguish between signals from other sources; those photons would still interact with the ariel creating fluctuating currents?
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    Quote Originally Posted by himnextdoor
    Any device that can receive radio waves whether they be photons or electro-magnetic waves is actually doing nothing more than sampling space and transducing an energy value over time.

    The receiving apparatus has to interact with the energy it is detecting, converting one form of energy into another.

    Sticking with the photon model:

    Suppose a radio-tranmitter was broadcasting a signal at a constant frequency of one-megahertz and a radio is receiving the signal via a dipole ariel. Reception occurs when photons interact with the eletrons in the ariel and causes a current to flow that is proportion to the modulation of the radio-signal.

    However, the interaction between the photons and the electrons of the ariel are a random process. The situation could occur where two photons conveying identical energy/wavelength/spin characteristics interact with two different electrons in two completely different ways. The two photons would make different contribution to the signal current. In fact, this would be the case for all the photons; the signal detected by the radio would be random, just white-noise.

    Does that make sense?

    Doesn't the fact that this doesn't happen go to prove that 'photons' are not real?

    In no way do I intend to detract from the usefullness of the photon-model but I am not sure that it is more accurate to say that 'energy comes as particles' than it is to say, 'it is as if energy comes in particles'.
    No it does not make sense.

    You are mixing thing willy=nilly.

    Communication theory, in particular the models for modulation are based on classical electromagnetic wave theory, Maxwell's classical equations. That in turn is based on the behavioir of many many photons which comprise an electromagnetic wave.

    Photons are very real.

    You probably need to study the theory of communciation electronics. A good book, though somewhat advanced, is Fields and Waves in Communication Electronics by Ramo, Whinnery and Van Duzer. You might also want to look at something convering elemetary communication theory. Lahti has a pretty good book.
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    You need to understand the difference between single events at the quantum scale and the average of an unimaginable number of events at the everyday scale. While the interactions of any 1 photon with any 1 electron may be random, the average is not and is well understood. At the every day scale, some many of the events occur that the average is all that matters.
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    And long-wave radio signals 'skip' between the ground and the atmosphere to be received in other countries around the world. What relationship would a photon arriving at the receiving ariel have with the original signal that has been absorbed and re-emitted multiple times? It wouldn't be just quiet, it would be 'garbled'.

    It's not like photons can 'bounce' is it?
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    No. An individual photon cannot bounce; however, the collection of all the photons coming off of a radio transmitter can. The photons in the new wavefront are not the same photons as the original wavefront, but they aren't garbled either. The average energy and frequency of the photons doesn't change when the signal bounces (the phase does, but that doesn't matter to radios).

    Again, you need to understand the differences between a single event and the average of a large number of events.
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    Quote Originally Posted by himnextdoor
    And long-wave radio signals 'skip' between the ground and the atmosphere to be received in other countries around the world. What relationship would a photon arriving at the receiving ariel have with the original signal that has been absorbed and re-emitted multiple times? It wouldn't be just quiet, it would be 'garbled'.

    It's not like photons can 'bounce' is it?
    You are mixing metaphors.

    All photons of a given energy/frequency are absolutely identical. So if a photon interacts with a surface and new photon is emitted of the same energy, you cannot tell the difference between bouncing and absorption and re-emission. So, yes, photons can bounce in that sense, which is all the sense that is needed.

    The process does not garble the signal.

    Consider a piece of glass. You can see through the glass clearly. Yet the photons that reach your eye are not the same photons that entered the glass.

    Or think of a mirror.
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    Quote Originally Posted by DrRocket
    You are mixing metaphors.

    All photons of a given energy/frequency are absolutely identical. So if a photon interacts with a surface and new photon is emitted of the same energy, you cannot tell the difference between bouncing and absorption and re-emission. So, yes, photons can bounce in that sense, which is all the sense that is needed.

    The process does not garble the signal.

    Consider a piece of glass. You can see through the glass clearly. Yet the photons that reach your eye are not the same photons that entered the glass.

    Or think of a mirror.
    Are you sure?

    If a photon didn't interact with the atmosphere (as most of them don't) then it (they) would just fly off into space and the ones that do interact would most likely involve an electron. There is no way to know, or even expect, that emitted photons are following the same path. It is likely that half of the interactions would result in photons going out into space. The rest would diverge exponentially as they were scattered first by the atmosphere and then by the ground.
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    With the low frecquency radiowaves it is interesting to think before the signal is emitted (radio and transmitter still off) and if the signal is just one quantum (which should theoretically be possible to receive) does this one quantum have allready this "bouncing"between" higher atmosphere and earth ?

    If yes C meassured between radio and transmitter would be very low, I mean the times I was drunk I wasn,t walking much slower then usual but nervertheless it took me much more time to go from A to B. I mean I can understand it maybe once the connection is made and functioning fully with a multitude of fotons invlolved. But from zero connection first to that and what is inbetween in the process of starting up ?
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    Quote Originally Posted by himnextdoor
    Quote Originally Posted by DrRocket
    You are mixing metaphors.

    All photons of a given energy/frequency are absolutely identical. So if a photon interacts with a surface and new photon is emitted of the same energy, you cannot tell the difference between bouncing and absorption and re-emission. So, yes, photons can bounce in that sense, which is all the sense that is needed.

    The process does not garble the signal.

    Consider a piece of glass. You can see through the glass clearly. Yet the photons that reach your eye are not the same photons that entered the glass.

    Or think of a mirror.
    Are you sure?

    If a photon didn't interact with the atmosphere (as most of them don't) then it (they) would just fly off into space and the ones that do interact would most likely involve an electron. There is no way to know, or even expect, that emitted photons are following the same path. It is likely that half of the interactions would result in photons going out into space. The rest would diverge exponentially as they were scattered first by the atmosphere and then by the ground.
    Why of course you are absolutely correct.

    The atmosphere is reflective and we can't see the stars or the moon, nor can astronauts see the Earth. In fact all of those high-resolution spy satellites are fakes.

    It is all a governmente conspiriacy, including all those astronomical observations from ancient Greece.
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    Why of course you are absolutely correct.
    Could it be you,re a teacher (or have been) as you seem to start almost every post with connotations as false, wrong, correct etc. to others contributions.
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    In order for absorption to take place, the photon's energy (wavelength) has to match the energy required to change an electron's energy-state. Otherwise, the electron is 'invisible' to the photon.

    It is likely that practically all the photons generated from an RF source would fail to meet the requirement for changing any electron's energy state and would therefore pass on through to space.

    Quote Originally Posted by DrRocket
    The atmosphere is reflective and we can't see the stars or the moon, nor can astronauts see the Earth.
    Not only can you see the earth from space, you can listen to all the radio stations too.
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    Not only can you see the earth from space, you can listen to all the radio stations too.
    The lower the frecquency the harder this gets. Has nothing to do with reflection though but with relativistic effect. Earth tends to hold the signal (curves it as timespace).
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    @himnextdoor, there's a reason that such signals show up stronger when there's a heavy cloud cover. It's exactly because such cover provides numerous electrons that can bounce the signal back down. And yes, by cthe conservation laws, we can expect for the reemitted photons to be travelling in a certain direction.

    @Ghrasp, the Earth's gravity well is no where near deep enough to hold on to any form of electromagnetic radiation. Consider how much more massive the Sun is, but we can still see it, even in the microwave spectrum.
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    Quote Originally Posted by Ghrasp
    Not only can you see the earth from space, you can listen to all the radio stations too.
    The lower the frecquency the harder this gets. Has nothing to do with reflection though but with relativistic effect. Earth tends to hold the signal (curves it as timespace).
    True; I think the atmosphere bends the wave toward earth by diffraction. Long waves can travel over the ground and don't have to be in the line of sight.

    To my mind, photons would make more sense if they dropped the wavelength characteristic. At least then they could represent a wave by having their density modulated in the same way that electrons represent a signal; the electron density is modulated.

    The photon can have spin (to give it a magnetic moment) and can represent the smallest unit of electro-static charge. A cross-sectional group of photons would create a 'local frame' which would connect it to other groups (local frames) transmitted in front of and behind it through magnetic dipole alignment and a 'global field' is formed which binds the whole structure together. This 'binding' of the fields is how a receiver can distinguish whether or not a detected photon belongs to the desired signal.

    If we must invent particles, let's make them sensible.
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    Quote Originally Posted by MagiMaster
    @himnextdoor, there's a reason that such signals show up stronger when there's a heavy cloud cover. It's exactly because such cover provides numerous electrons that can bounce the signal back down. And yes, by cthe conservation laws, we can expect for the reemitted photons to be travelling in a certain direction.

    @Ghrasp, the Earth's gravity well is no where near deep enough to hold on to any form of electromagnetic radiation. Consider how much more massive the Sun is, but we can still see it, even in the microwave spectrum.
    Sorry, I posted that before I read the other.

    Yes, clouds would help, but I think I should have said AM radio wave; long waves are a special case being ground waves.

    In general, I think AM waves do bounce of the ionosphere which acts like a barrier.
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    Quote Originally Posted by Ghrasp
    Could it be you,re a teacher (or have been) as you seem to start almost every post with connotations as false, wrong, correct etc. to others contributions.
    Lol. Im trying to figure this out as well. Being an ex-teacher is a good hypothesis....
    "Doubt is the origin of Wisdom" - Rene Descartes
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    Quote Originally Posted by himnextdoor
    Quote Originally Posted by Ghrasp
    Not only can you see the earth from space, you can listen to all the radio stations too.
    The lower the frecquency the harder this gets. Has nothing to do with reflection though but with relativistic effect. Earth tends to hold the signal (curves it as timespace).
    True; I think the atmosphere bends the wave toward earth by diffraction. Long waves can travel over the ground and don't have to be in the line of sight.

    To my mind, photons would make more sense if they dropped the wavelength characteristic. At least then they could represent a wave by having their density modulated in the same way that electrons represent a signal; the electron density is modulated.

    The photon can have spin (to give it a magnetic moment) and can represent the smallest unit of electro-static charge. A cross-sectional group of photons would create a 'local frame' which would connect it to other groups (local frames) transmitted in front of and behind it through magnetic dipole alignment and a 'global field' is formed which binds the whole structure together. This 'binding' of the fields is how a receiver can distinguish whether or not a detected photon belongs to the desired signal.

    If we must invent particles, let's make them sensible.
    You really need to do a bit of studying. This is total gibberish.

    Photons have no charge whatever.

    Your description of a radio receiver is gibberish. Not right. Not even wrong.
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    True; I think the atmosphere bends the wave toward earth by diffraction. Long waves can travel over the ground and don't have to be in the line of sight.
    Maybe you mean the same but I was thinking gravity having more influence if the frecquency is lower. In the sense of "earth curves spacetime". This idea also came up simultaneously with radio.

    @Ghrasp, the Earth's gravity well is no where near deep enough to hold on to any form of electromagnetic radiation. Consider how much more massive the Sun is, but we can still see it, even in the microwave spectrum.
    Are you sure ? It is known that stars seen during an eclipse seem te be shifted to a different position by the sun (and or the moon offcourse). So earth wil have this effect for sure on radio signals. Only point is to which extend. The sunlight we receive is mostly higher frecquency also.

    Also radio,s work on electricity that has a phase and a non-phase. The source that delivers the energy is connected to earths surface by earthing electrodes. This might increase the effect somehow making it more difficult for the transmitter "to reach higher" as it is conected to the energyproviding devices it is like nailed to the ground.. Using a transmission setup that is freestanding the effect could be less. I have no experimental proof for it. But I doubt that radiotechnicque used for spacetrips uses the daily electricity network.
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    Quote Originally Posted by Ghrasp
    True; I think the atmosphere bends the wave toward earth by diffraction. Long waves can travel over the ground and don't have to be in the line of sight.
    Maybe you mean the same but I was thinking gravity having more influence if the frecquency is lower. In the sense of "earth curves spacetime". This idea also came up simultaneously with radio.

    @Ghrasp, the Earth's gravity well is no where near deep enough to hold on to any form of electromagnetic radiation. Consider how much more massive the Sun is, but we can still see it, even in the microwave spectrum.
    Are you sure ? It is known that stars seen during an eclipse seem te be shifted to a different position by the sun (and or the moon offcourse). So earth wil have this effect for sure on radio signals. Only point is to which extend. The sunlight we receive is mostly higher frecquency also.
    1. A beam of light originating far from the Sun and just grazing its surface will deflect by a total of 1.7 arc seconds. The same beam grazing the Earth's surface would deflect by 1/3000th as much. This works out to about 3.5 cm of deflection over a distance equal to the diameter of the Earth.

    2. The frequency has no bearing on this, all electromagnetic radiation would deflect by the same amount. Higher frequencies are more energetic, but it is the energy-momentum that gravity couples with, so more energy means a stronger coupling with gravity.
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    Quote Originally Posted by Ghrasp
    [

    Also radio,s work on electricity that has a phase and a non-phase.
    Baloney.

    Did you fail electrical engineering while you were failing physics ?
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    @himnextdoor. You've expressed a very common and practically always wrong sentiment. Just because something doesn't make sense to you don't make it false. All that matters in science is can a given theory make predictions that are borne out by experiments. Making sense doesn't have anything to do with it.
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    Quote Originally Posted by DrRocket
    Your description of a radio receiver is gibberish. Not right. Not even wrong.
    You're right, a receiver doesn't work that way.

    What really happens is that electromagnetic radiation (a magnetised field) cuts the coils in the myriad virtual L-C circuits that comprise the ariel causing them to resonate. The generated induced currents are transformed, detected, demodulated, then amplified and output to a speaker. Shouldn't leave out the i.f. stage I suppose.

    Electromagnetic wave to sound wave.

    Unless, of course, magnetic fields are made of photons;

    Waves.
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    @Ghrasp I just found out something interesting; the earth itself is a medium through which long waves can travel. The ground and the atmosphere form a diffracting region.

    Science is cool. 8)
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    Quote Originally Posted by himnextdoor
    Quote Originally Posted by DrRocket
    Your description of a radio receiver is gibberish. Not right. Not even wrong.
    You're right, a receiver doesn't work that way.

    What really happens is that electromagnetic radiation (a magnetised field) cuts the coils in the myriad virtual L-C circuits that comprise the ariel causing them to resonate. The generated induced currents are transformed, detected, demodulated, then amplified and output to a speaker. Shouldn't leave out the i.f. stage I suppose.

    Electromagnetic wave to sound wave.

    Unless, of course, magnetic fields are made of photons;

    Waves.
    Yep. Electromagnetic fields are made of photons.

    Electromagnetic radiation, an electromagnetic field is not a "magnetized field" but rather a field with two components, and electric field (aka E field) and a magnetic field (aka B field), described classically by Maxwell's equations. But at a more fundamental level, that of quantum field theory, the field is indeed composed of photons.

    More importantly, one does not get a propagating field that is either exclusively an E field or exclusively a B field.

    But the classical theory serves quite well enough to describe antennas and even circuits, and so is enough to design a radio. The operation is somewhat different from what you describe, though you did throw in a couple of standard "buzz words". It would be better if you knew what they meant.

    Were you and Ghrasp classmates in infamy ?
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    Quote Originally Posted by MagiMaster
    @himnextdoor. You've expressed a very common and practically always wrong sentiment. Just because something doesn't make sense to you don't make it false. All that matters in science is can a given theory make predictions that are borne out by experiments. Making sense doesn't have anything to do with it.
    Alright. I'm prepared to accept your premise to a certain extent

    But tell me, point out to me one post that has gone anywhere towards putting me right. That is, right within your terms of reference. Or Rocket's.

    Gibberish! Nonsense! These are word such as were spat at Gallileo when he dared to think of a helio-centric system.

    And don't you find it irksome that DrRocket only seems to post that he's not even going to bother to post. Like, "Look at me, I'm ignoring you".

    And MagiMaster, if I was as familiar with the truth of physics as you or DrRocket seem to be; if 'I don't Know' came to be words that were not familiar to me, I would take great joy from spreading the word.

    Is science really this exclusive?

    For the record, my current view is that photons are to physics what successive approximation is to the area of a curve. It will yield results that are close enough to secure research grants but in the end, there will be another model.

    I learn something new everyday.

    Science must always be willing to learn.
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    @DrRocket, I was referring to the type of field produced by a permanent magnet.

    I do find it interesting though that photons can create a force capable of magnetic attraction. Is that what you are saying; that photons can impart a kinetic force? That the iron-filing pattern made with an electro-magnet corresponds to an arrangement of photons?

    I was under the impression that when a current flows through a coil that it was the movement of electrons through space that caused the force of magnetism and that that magnetism had the same quality and structure of a field such as that which occurs in the domains that form a structure in iron. As if each electron carried a disc of magnetism with its diameter at a right-angle to the direction of current. I imagined a chain, or snake, of discs following the electrons along the wire creating the lines of force.

    Or are those lines of force populated by photons too?

    P.S. You know when you watch a splash of water in slow motion and you always get that bit of the water that recoils from the centre of the impact; that globule that seems to hang there, gently vibrating as if were made of jelly? Is that how you imagine a photon? Being 'shaped' by its spin?
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    Quote Originally Posted by himnextdoor
    @DrRocket, I was referring to the type of field produced by a permanent magnet.

    I do find it interesting though that photons can create a force capable of magnetic attraction. Is that what you are saying; that photons can impart a kinetic force? That the iron-filing pattern made with an electro-magnet corresponds to an arrangement of photons?

    I was under the impression that when a current flows through a coil that it was the movement of electrons through space that caused the force of magnetism and that that magnetism had the same quality and structure of a field such as that which occurs in the domains that form a structure in iron. As if each electron carried a disc of magnetism with its diameter at a right-angle to the direction of current. I imagined a chain, or snake, of discs following the electrons along the wire creating the lines of force.

    Or are those lines of force populated by photons too?

    P.S. You know when you watch a splash of water in slow motion and you always get that bit of the water that recoils from the centre of the impact; that globule that seems to hang there, gently vibrating as if were made of jelly? Is that how you imagine a photon? Being 'shaped' by its spin?
    Lines of force are not "populated" by anything. But the electromagnetic force is the result of the action of virtual photons.

    The field of a permanent magnet is the result of the magnetic moment of the atoms that comprise the magnet, primarily oriented in a single direction. That involves virtual photons at the quantum level.

    Virtual photons are responsible for the electromagnetic force. There is no such thing as a kinetic force.

    I have no idea what you are talking about in the last paragraph. It has nothing to do with physics.

    If you want to understand some physics, stop spouting nonsense and read a good book on the subject. Probably the very best introduction is The Feynman Lectures on Physics by Feynman, Leighton and Sands. It is the content of lectures that Feynman gave to a freshman physics class at Cal Tech in the 1960's. It is still the best physics book at that level that exists. For a reasonably accessible explanation of photons and the physics involving them Feynman's QED is excellent. It is a set of lectures that he gave to a general audience on the subject of quantum electrodynamics, and is a masterpiece, by a master of the subject.

    If you want to learn ask a question. If want criticism, make ridiculous assertions.
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    Quote Originally Posted by himnextdoor
    Quote Originally Posted by MagiMaster
    @himnextdoor. You've expressed a very common and practically always wrong sentiment. Just because something doesn't make sense to you don't make it false. All that matters in science is can a given theory make predictions that are borne out by experiments. Making sense doesn't have anything to do with it.
    Alright. I'm prepared to accept your premise to a certain extent

    But tell me, point out to me one post that has gone anywhere towards putting me right. That is, right within your terms of reference. Or Rocket's.

    Gibberish! Nonsense! These are word such as were spat at Gallileo when he dared to think of a helio-centric system.

    And don't you find it irksome that DrRocket only seems to post that he's not even going to bother to post. Like, "Look at me, I'm ignoring you".

    And MagiMaster, if I was as familiar with the truth of physics as you or DrRocket seem to be; if 'I don't Know' came to be words that were not familiar to me, I would take great joy from spreading the word.

    Is science really this exclusive?

    For the record, my current view is that photons are to physics what successive approximation is to the area of a curve. It will yield results that are close enough to secure research grants but in the end, there will be another model.

    I learn something new everyday.

    Science must always be willing to learn.
    All of my posts have attempted to put you right, and yes, sometimes some of DrRocket's posts annoy me a little, but that doesn't make him any less right when he says something substantive.

    All of science is a series of successive approximations. Those approximations are getting very good, but we know they're not complete. We know there will be another model, but we don't know what it is yet.

    There's nothing exclusive about science either. There is one important point that's overlooked by too many would-be amateurs though. That is the correspondence principal. Basically what that means is that theory might change, but observations don't. Any new theory must account for all the numerous observational evidence that has already been collected. For example, any new theory must predict that an atomic clock on an airplane will lose time compared to one on the ground since that is an observation, not a theory. When a new theory does not match previous observations, it can be thrown away almost immediately.

    Also, "I don't know" may be the three most common words I utter. It's just that I never bother to put that in writing. Generally speaking, if I don't know the answer to a question, I don't bother to post at all.

    Finally, I'll say that I agree with DrRocket's latest point. Ask questions, but don't make assertions. It's fine to say "What happens to the light coming from a laser as it falls into a black hole?" If you say "I think ... happens when a laser falls into a black hole and therefore ...", expect someone to say, "that's not what happens."
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    @Ghrasp I just found out something interesting; the earth itself is a medium through which long waves can travel. The ground and the atmosphere form a diffracting region.
    I know, the signal is not limited to one medium. That notion was part of my thinking about the possible influence of the "topology" of the system as a whole (transmitter and the energysupplying devices) on the signal. If you put a plug in a electricity system making the electric connection the parts even weld together superfluous. Suppose I have a transmitter with a freestanding generator on a wooden floor in operation. the transmitter works on two poles (ac off course) but no relative tension to the ground (at least you can,t meassure a phase then). Now I put one pole of the generator to an earth electrode. The other becomes a phase.
    As the transmitter and the generator ar a whole (because of the weld) I could imagine this has some effect on the signal too.


    The arc at which light from a star "bows" is not a constant throughout the trajektory as it is connected to gravity and as you know gravity is distance related. In this case of radio the distance is very short, the signal is not grazing earth it originates from it.
    For lower frecquencies and specific situations earth could really work as a blackhole with in this case the outer atmosphere as a horizon for lower frecquencies.
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    Quote Originally Posted by Ghrasp

    The arc at which light from a star "bows" is not a constant throughout the trajektory as it is connected to gravity and as you know gravity is distance related. In this case of radio the distance is very short, the signal is not grazing earth it originates from it.
    A signal originating at the surface would show show even less deflection. The value I gave was for the total deflection angle. Since a light signal orginating from the surface spends less time in the Earth's gravity well, it's total deflection would be less.

    For lower frecquencies and specific situations earth could really work as a blackhole with in this case the outer atmosphere as a horizon for lower frecquencies.
    Again, the frequency does not matter. All frequencies are effected equally by gravity.
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    A signal originating at the surface would show show even less deflection. The value I gave was for the total deflection angle. Since a light signal orginating from the surface spends less time in the Earth's gravity well, it's total deflection would be less.
    What I meant was that the light from a star is influenced by the sun and or the moon not as much before it passes them at close range. Part of that light (but you won,t see it offcourse) will also be absorbed by the sun or moon (or moon because I can hardly imagine the sun to absorb light ) due to that the light beam as a whole bends (or tends) towards the sun (or moon or both). stonger when the distance is shorter. So the distance for the light where the effect is significant is also not to long.

    In this case the distance starts from zero especially if you realize (as himnextdoor pointed out) the signal exists also underneath the earths surface (even in the waterlayer that almost covers the entire earth except some mountains).

    But it is to how you look at curved spacetime. A bar doesn,t curve because you curve it but due to momentum. The curvation of the light does it really come from a curved spacetime or simply because the light is attracted towards the sun (or moon ?) light seeks shadow you could say. That results in a curvation then. In case of the radio from earth the gravity field is directed towards earth and therefor the signals loose energy when the altitude is higher.

    As higher frecquency's are said to have higher energy, they will reach higher then lower frecquencies even if effected the same.

    At this moment these are my thoughts on this subjekt I hope I am allowed to have them and keep them till I think it is necessary to change them (because of arguments, logic or experiments showing it,s different.

    I,m also not blabbering nonsense about the influence of the earth electrode(s) on the generator that provides the energy. Because typical for nonsense is that it is impossible to to proof (or show) it or disproof it. In this case it would be easy to disproof it so I,m allowed to stand for the idea till proven wrong.
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    Yes. A radio signal (and any other form of electromagnetic radiation) will lose energy as it climbs out of Earth's gravity well; however, Earth's gravity is weak enough (and the moon's even more so) that that energy loss will be tiny.

    Also, the Sun would easily absorb any light that hits it. Just because it produces light don't mean it's transparent.
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    Quote Originally Posted by Ghrasp
    A signal originating at the surface would show show even less deflection. The value I gave was for the total deflection angle. Since a light signal orginating from the surface spends less time in the Earth's gravity well, it's total deflection would be less.
    What I meant was that the light from a star is influenced by the sun and or the moon not as much before it passes them at close range. Part of that light (but you won,t see it offcourse) will also be absorbed by the sun or moon (or moon because I can hardly imagine the sun to absorb light ) due to that the light beam as a whole bends (or tends) towards the sun (or moon or both). stonger when the distance is shorter. So the distance for the light where the effect is significant is also not to long.
    If the defelection from the additive effect of gravity on the light over the whole path is insignificant, then the deflection from any part, will be even more so, because the deflection for the whole path includes any deflection over the shot path.

    In this case the distance starts from zero especially if you realize (as himnextdoor pointed out) the signal exists also underneath the earths surface (even in the waterlayer that almost covers the entire earth except some mountains).

    [/i]irrelevant[/i]

    But it is to how you look at curved spacetime. A bar doesn,t curve because you curve it but due to momentum. The curvation of the light does it really come from a curved spacetime or simply because the light is attracted towards the sun (or moon ?) light seeks shadow you could say. That results in a curvation then. In case of the radio from earth the gravity field is directed towards earth and therefor the signals loose energy when the altitude is higher.
    Any effect gravity has on light in the vicinity of the Earth is insignificant.

    As higher frecquency's are said to have higher energy, they will reach higher then lower frecquencies even if effected the same.
    No more so than a cannon ball fired at a certain velocity will rise higher than a tennis ball fired at the same velocity does, even though the cannon ball has a greater kinetic energy.

    At this moment these are my thoughts on this subjekt I hope I am allowed to have them and keep them till I think it is necessary to change them (because of arguments, logic or experiments showing it,s different.
    Be that as it may, such thoughts do not belong in the Physics forum and should be restricted to the New Ideas and Hypotheses forum, as they are definitely not in accordance with accepted science.
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    Quote Originally Posted by himnextdoor

    Gibberish! Nonsense! These are word such as were spat at Gallileo when he dared to think of a helio-centric system.
    No, they weren't. Even the Church at the time admitted that the Heliocentric model was more convenient. It just went against official Church doctrine ( Galileo disagreed with this as he thought that there was no conflict between the Bible and the Heliocentric system).

    And even the official doctrine was adopted in part in order to distance The Catholic church from Protestant church. It was a theological dispute not a scientific one.
    "Men are apt to mistake the strength of their feelings for the strength of their argument.
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    however, Earth's gravity is weak enough (and the moon's even more so) that that energy loss will be tiny.
    Is it necessarily a loss of energy (first law energy is not lost) the long wave signal for not reaching that high reaches further horizontally thus strakes a bigger area. It depends a lot of how you meassure. A warmlamp radiates to a much wider area, it is less concentrated in it,s direction so using a small surface detecting device you miss a bigger part of the energy. Like a tidal wave at sea ; measured locally the energy is not that high but it is still high energy.

    First law because if you put a transmitter and a generator in a closed box with some fuell in the generator if it transmits high frecquency or low doesn,t make much of a difference (only maybe a difference of the effectivity in transforming the energy).
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    @Magi, Ask question but don't make assertions? I'm looking at: "The Science Forum - Scientific Discussion and Debate". But don't make assertions. If you do you should expect patronisation and condescendence. Since when did science not make assertions; it routinely makes assumtions.

    My God! Think what it must have been like for Copernicus, to walk the earth knowing the truth with everyone muttering, 'Rubbish', or, 'Gibberish'.

    ----------------------------------------------------------------------------------------
    Ghrasp makes a very good point; the 'Mass warping Space-Time To Produce Gravity' model is just that; a good way to visualise the behaviour of gravity. A model.

    Why is science looking for Gravitons if space is warped? That is like searching for a 'waterfall particle' that affects water-molecules when they are in the region of a precipice. With a precipice, there is no need for a 'waterfall particle'.

    And yet they search.

    What if space isn't warped and that it is gravity itself that causes the bending of light? (This is a rhetorical question; modern physics is at a loss as to the precise nature of gravity and magnetism and therefore its proponents would have to betray their indoctrinations in order to answer it.)

    This would means that space (which you all seem to accept can be warped) has a quality that is not yet understood (which you all seem to be resistant to).

    I'm not sure if I misunderstand Ghrasp but I'm prepared to explore the possibe nature of space and to continue to try and understand, and explain, gravity.
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    Quote Originally Posted by Janus
    Quote Originally Posted by himnextdoor

    Gibberish! Nonsense! These are word such as were spat at Gallileo when he dared to think of a helio-centric system.
    No, they weren't. Even the Church at the time admitted that the Heliocentric model was more convenient. It just went against official Church doctrine ( Galileo disagreed with this as he thought that there was no conflict between the Bible and the Heliocentric system).

    And even the official doctrine was adopted in part in order to distance The Catholic church from Protestant church. It was a theological dispute not a scientific one.
    Accepted but you take my point.

    There was resistance against scientific development.
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    Quote Originally Posted by himnextdoor
    @Magi, Ask question but don't make assertions? I'm looking at: "The Science Forum - Scientific Discussion and Debate". But don't make assertions. If you do you should expect patronisation and condescendence. Since when did science not make assertions; it routinely makes assumtions.
    Of course scientists make assertions. They make them all the time. Logical, well-reasoned assertions backed by a mountain of experimental data and sophisticated, well-supported theories.

    Inane, ridiculous assertions that demonstrate nothing so much as profound ignorance of basic physics and could mislead a naive reader (and there are more readers of these forums than there are participants by quite a large margin) are quite another thing. The potential to do damage to sincere and well-meaning lurkers far outweighs any irritation to the tender ego of someone who is posting nonsense.
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    Quote Originally Posted by DrRocket
    Quote Originally Posted by himnextdoor
    @Magi, Ask question but don't make assertions? I'm looking at: "The Science Forum - Scientific Discussion and Debate". But don't make assertions. If you do you should expect patronisation and condescendence. Since when did science not make assertions; it routinely makes assumtions.
    Inane, ridiculous assertions that demonstrate nothing so much as profound ignorance of basic physics and could mislead a naive reader (and there are more readers of these forums than there are participants by quite a large margin) are quite another thing. The potential to do damage to sincere and well-meaning lurkers far outweighs any irritation to the tender ego of someone who is posting nonsense.
    Give me an example of an inane or rediculous assertion. Just one.

    Nonsense and gibberish seems to be the basis for all of your scientific observations which, strangely, aren't yours anyway.

    And I think 'lurker' has negative connotations.

    And while we're on the subject, if you think that people use this site to find difinitive answers to 'un-answerable' questions then I think you have delusions of grandeur and the arrogance to stuff a black-hole to the gills.

    It says discussion and debate. Who are you to restrict people's thinking?

    Go read this, go read that, go read the other. That's how priests answer questions when they haven't got a clue.
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    Why is science looking for Gravitons if space is warped? That is like searching for a 'waterfall particle' that affects water-molecules when they are in the region of a precipice. With a precipice, there is no need for a 'waterfall particle'.
    Maybe gravitons are curving timespace so fotons can follow their curved path thinking it is straight.
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    Quote Originally Posted by himnextdoor
    Quote Originally Posted by DrRocket
    Quote Originally Posted by himnextdoor
    @Magi, Ask question but don't make assertions? I'm looking at: "The Science Forum - Scientific Discussion and Debate". But don't make assertions. If you do you should expect patronisation and condescendence. Since when did science not make assertions; it routinely makes assumtions.
    Inane, ridiculous assertions that demonstrate nothing so much as profound ignorance of basic physics and could mislead a naive reader (and there are more readers of these forums than there are participants by quite a large margin) are quite another thing. The potential to do damage to sincere and well-meaning lurkers far outweighs any irritation to the tender ego of someone who is posting nonsense.
    Give me an example of an inane or rediculous assertion. Just one.
    How about I give you three:

    Quote Originally Posted by himnextdoor
    Why is science looking for Gravitons if space is warped? That is like searching for a 'waterfall particle' that affects water-molecules when they are in the region of a precipice. With a precipice, there is no need for a 'waterfall particle'.
    Quote Originally Posted by himnextdoor
    (This is a rhetorical question; modern physics is at a loss as to the precise nature of gravity and magnetism and therefore its proponents would have to betray their indoctrinations in order to answer it.)
    Quote Originally Posted by himnextdoor
    This would means that space (which you all seem to accept can be warped) has a quality that is not yet understood (which you all seem to be resistant to).
    On the topic of gravitons: some parts of science says that we should expect to find them. Other parts say that gravitons don't make much sense. Still others seem to get along fine with or with out them. Therefore, we should look for them to see which parts are more correct and where to go next.

    Around here "lurker" doesn't have any such connotations. It just means someone who reads but does not post. (This is true on almost all message boards I've ever read.) Lurkers reading on this site in particular (and other similar sites) may or may not know anything about these topics. Those that don't also don't know anything about the people posting answers to other peoples' questions. If noone rebuffs an incorrect answer, those people will assume it's correct and go off and repeat that as fact. (People are just like that.) Therefore, it's important that when someone asks a question, the answers given are correct as far as modern science knows.

    And I said you should expect someone to tell you that you're wrong.
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    If noone rebuffs an incorrect answer, those people will assume it's correct and go off and repeat that as fact.
    You really think someone would listen to it ? Or other way around someone reads something on internet that is correct and tells it ? I never witnessed anyones real interest in what I or someone else reads on internet. (so what am I doing here ?)
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    Yes. There are people that will read something, then forget where they read it, then repeat what they read as fact. It happens a lot. Maybe it doesn't happen as often with message boards as, say, newspaper editorials, but it still happens.
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    I'm wounded.

    For the sake of fairness, the phrase 'This is a rhetorical question' referred to a question that preceded it.

    And one should be careful about judging people on their spelling and grammar.

    Apart from that, I thought it was well put. We'll agree to differ.

    Since I joined this site, I have found out about the Casimir effect, the Ramar effect, Langrangian points and through pure love of the subject tried to engage in discussion about things that are interesting. Yes, sometimes there is inanity (how fast does light travel in a washing machine) but there is no law that says a scientific discussion can't have any humour, that it has to be rigidly serious. The twin paradox can be discussed but faster than light travel gets poo-pooed.

    Well fine. I'll still enjoy talking about things that may turn out to be impossible because there is always something to be learned.

    Even when you're wrong.

    I think the question of what it is about space that restricts the speed of light is an interesting one; if noone asks, noone'll know.
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    The point I'm trying to make, and I'm trying to be friendly about it, is that asking questions is good. Speculating is alright. But you need to listen when someone tells you that there are existing reasons that invalidate your speculations.

    "What is it about space that restricts the speed of light?" is a fine question, one I'm sure DrRocket can answer (even if that answer is it's not a property of space). Ask it, but if you start by saying "it doesn't make sense for photons to be particles" (for example), expect the responses to center around "but photons are particles (and waves)."

    Oh, and a rhetorical question is a question asked to make a point, not get an answer, which is exactly the opposite of what you should be doing.
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    Quote Originally Posted by himnextdoor
    I think the question of what it is about space that restricts the speed of light is an interesting one; if noone asks, noone'll know.
    There is no true answer to why light travels at c. It is just a fundamental fact that cannot be explained.
    "Doubt is the origin of Wisdom" - Rene Descartes
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    [quote="MagiMaster"]The point I'm trying to make, and I'm trying to be friendly about it, is that asking questions is good.[quote]

    I'm sorry if my tone has come accross as hostile, that was absolutely not my intention.

    My thinking is that you test a model's weaknesses as much as you test its strength and, correct me if I'm wrong, magnetism, how it exerts its 'suck' or 'blow', is a bit of a stumbling block. Kinda like gravity, large pieces of metal can propel themselves together over appreciable distances with acceleration. Very similar to gravity, in fact.

    The sun's gravity extends to about half a light year; what would that equate to at an atomic scale. Similar?
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    Quote Originally Posted by MagiMaster
    The point I'm trying to make, and I'm trying to be friendly about it, is that asking questions is good.
    I'm sorry if my tone has come accross as hostile, that was absolutely not my intention.

    My thinking is that you test a model's weaknesses as much as you test its strength and, correct me if I'm wrong, magnetism, how it exerts its 'suck' or 'blow', is a bit of a stumbling block. Kinda like gravity, large pieces of metal can propel themselves together over appreciable distances with acceleration. Very similar to gravity, in fact.

    The sun's gravity extends to about half a light year; what would that equate to at an atomic scale. Similar?
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    The mechanisms behind electromagnetism are pretty well understood (but not necessarily by me). It has to do with the exchange of virtual photons, but how exactly this produces all the effects of electromagnetism (including permanent magnets) is beyond my current knowledge.
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    Quote Originally Posted by MagiMaster
    The mechanisms behind electromagnetism are pretty well understood (but not necessarily by me). It has to do with the exchange of virtual photons, but how exactly this produces all the effects of electromagnetism (including permanent magnets) is beyond my current knowledge.
    Is even worth asking if a, the photon has a tiny amount of space inside it (like a bubble) at its centre and b, does the photon carry an oscillating component that corresponds to its energy. Does the rate of its spin represent frequency, for example or is it the undulations on the surface of the photon, if I can describe it that way?

    I mean, can I think of a photon as a tiny globule of water that is spinning around an axis?
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    I don't think it'd be a good idea to imagine it as anything with volume. The kind of spin you're talking about isn't exactly like a spinning ball either. For one thing, it can only occur in multiples of 1/2. All of this is still at the edge of my understanding, so you'd probably be better off asking someone else to explain further.
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    Quote Originally Posted by himnextdoor
    Quote Originally Posted by MagiMaster
    The mechanisms behind electromagnetism are pretty well understood (but not necessarily by me). It has to do with the exchange of virtual photons, but how exactly this produces all the effects of electromagnetism (including permanent magnets) is beyond my current knowledge.
    Is even worth asking if a, the photon has a tiny amount of space inside it (like a bubble) at its centre and b, does the photon carry an oscillating component that corresponds to its energy. Does the rate of its spin represent frequency, for example or is it the undulations on the surface of the photon, if I can describe it that way?

    I mean, can I think of a photon as a tiny globule of water that is spinning around an axis?
    No

    A photon is a point particle. It does not have an interior. There is nothing going on "inside" it. It has no volume. It does not have a surface.

    Photons are spin 1 particles. That has nothing to do with the frequency. Spin does not mean what you probably think it means. http://en.wikipedia.org/wiki/Spin_(physics).

    PLEASE go read a book on basic theory of the electromagnetic interaction. As mentioned to you elsewhere Feynman's little book QED is very good and very readable by non-specialists.
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    Quote Originally Posted by himnextdoor
    Is even worth asking if a, the photon has a tiny amount of space inside it
    No.

    Quote Originally Posted by himnextdoor
    does the photon carry an oscillating component that corresponds to its energy. Does the rate of its spin represent frequency, for example or is it the undulations on the surface of the photon, if I can describe it that way?
    It's frequency describes it's energy.

    Quote Originally Posted by himnextdoor
    I mean, can I think of a photon as a tiny globule of water that is spinning around an axis?
    There's classical physics, and quantum physics.
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    A photon is a point particle.
    Then what is the meaning of attributing a wavelength to it ?

    Just asking.
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    Quote Originally Posted by DrRocket
    A photon is a point particle. It does not have an interior. There is nothing going on "inside" it. It has no volume. It does not have a surface.
    This is completely ABSURD. How can something without a volume or a surface area do anything? It doesnt even exist.... If something doesnt have a volume, then technically it doesnt even take up space, which means it doesnt exist. Where is your intelligence? All you do is repeat what you read in a textbook, which is the best and surest way to pass on errors. How can you honestly think this is right? What a tragedy, I feel incredibly sorry for you.

    Does anyone else here have the intellect to realise that the area of physics is in a HUGE mess at the moment?
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    Quote Originally Posted by Waveman28
    [This is completely ABSURD. How can something without a volume or a surface area do anything?
    What are the four fundenmental forces of the universe.



    Quote Originally Posted by Waveman28
    It doesnt even exist.... If something doesnt have a volume, then technically it doesnt even take up space, which means it doesnt exist. Where is your intelligence?
    Electromagnetic waves don't take up space. They perturbe space.

    Quote Originally Posted by Waveman28
    [All you do is repeat what you read in a textbook, which is the best and surest way to pass on errors. How can you honestly think this is right? What a tragedy, I feel incredibly sorry for you.
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    There are people that will read something, then forget where they read it, then repeat what they read as fact. It happens a lot. Maybe it doesn't happen as often with message boards as, say, newspaper editorials, but it still happens.
    I don,t think so someone just replicating what he has read is as boring and uninteresting as you can get. Right or wrong doesn,t make a difference.
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    - What are the four fundenmental forces of the universe?
    - Electromagnetic waves don't take up space. They perturbe space.
    So now you agree with me that light is a wave and not made of photons? Even better, you are also saying that they perturb, thus suggesting a medium for their propagation? If so, good, because the Ether exists. The Ether is the only thing which exists and the waves in this ether is what everything is made of. Thus, forces dont exist, but things can still accelerate and move due to interference effects.

    Well, fuck off then.
    Getting a bit sensitive are we?
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    Quote Originally Posted by Waveman28
    Quote Originally Posted by DrRocket
    A photon is a point particle. It does not have an interior. There is nothing going on "inside" it. It has no volume. It does not have a surface.
    This is completely ABSURD. How can something without a volume or a surface area do anything? It doesnt even exist.... If something doesnt have a volume, then technically it doesnt even take up space, which means it doesnt exist. Where is your intelligence? All you do is repeat what you read in a textbook, which is the best and surest way to pass on errors. How can you honestly think this is right? What a tragedy, I feel incredibly sorry for you.

    Does anyone else here have the intellect to realise that the area of physics is in a HUGE mess at the moment?
    As usual, you have no idea what you are talking about.

    Whether it appears absurd to you or not is totally irrelevant. What I have described to you is the content of the best available physical theory, in this case quantum electrodynamics.

    If you simply want to reject modern physics then confine your delusons to Pseudoscience. They have no place in a physics forum.
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  90. #89  
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    Quote Originally Posted by Waveman28
    This is completely ABSURD. How can something without a volume or a surface area do anything? It doesnt even exist.... If something doesnt have a volume, then technically it doesnt even take up space, which means it doesnt exist.

    -Wave–particle duality and uncertainty principles-
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    "Mathematicians stand on each other's shoulders."- Carl Friedrich Gauss


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  91. #90  
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    Quote Originally Posted by Waveman28

    Does anyone else here have the intellect to realise that the area of physics is in a HUGE mess at the moment?
    What I see is someone who has failed to come to grips with what modern Physics has to say, and who's ego is too large to allow himself to admit that that failing might be his. Therefore, he tries to force the universe to fit within the limits of his own intellect.

    That being said, Any problem you personally may have with presently accepted physics belongs in the New Idea and Hypotheses forum.
    "Men are apt to mistake the strength of their feelings for the strength of their argument.
    The heated mind resents the chill touch & relentless scrutiny of logic"-W.E. Gladstone


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  92. #91  
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    Quote Originally Posted by Janus
    Therefore, he tries to force the universe to fit within the limits of his own intellect.
    The limitations imposed by the Heisenberg uncetainty principle in trying to confine ANYTHING to such a tiny volume would be enormous. Trying to do that with the universe is simply out of the question.
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  93. #92  
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    Quote Originally Posted by DrRocket
    Whether it appears absurd to you or not is totally irrelevant. What I have described to you is the content of the best available physical theory, in this case quantum electrodynamics.

    If you simply want to reject modern physics then confine your delusons to Pseudoscience. They have no place in a physics forum.
    I'm not saying that you are wrong in terms of what Quantum Electrodynamics describes, clearly you know the theory very well. What I'm saying is that the theory itself is flawed.

    In science at present, we know about virtually all properties of the universe, we just are yet to explain them properly. I completely agree with all observations made in physics, it is just the explanation of them which I know is wrong. For example, we know that we cannot know the position and momentum of an electron simultaneously. However, explaining this phenomenon is where there error has arisen. Heisenberg thought that this was because an electron could be in multiple positions at once and that its wavefunction could collapse. That is not a sensible or logical explanation. I admit perfectly that the momentum and position of an elecctron cannot be known simultaneuosly, but for a much different reason than heisenbergs uncertainty principal. If we fire light at a 'particle', we give it extra momentum, so by the time the light has returned to us, the 'particles' position and momentum have changed. It is that simple. In this explanation, there are no assumptions or new creations, just common logic.

    Most areas of QM involve the use of Heisenbergs principal, thus this error is present in all of them. If something is fundamentally flawed, it can only lead us into a blind alley. The amount of errors in Physics has drastically built up in the last century, and we desperately need to revise phyisics as a whole from the start. This way, we can correct the errors of the past and arrive at a much more correct and satisfactory explanation of our universe.

    Quote Originally Posted by Janus
    What I see is someone who has failed to come to grips with what modern Physics has to say, and who's ego is too large to allow himself to admit that that failing might be his. Therefore, he tries to force the universe to fit within the limits of his own intellect.

    That being said, Any problem you personally may have with presently accepted physics belongs in the New Idea and Hypotheses forum.
    It is not that I do not understand Physics, it is that I understand that many of the theories in Physics are wrong. I have a very good understanding of modern mainstream physics, which has allowed me to make an informed decision about it, and I have come to the obvious and sensible conclusion that many explanations in Physics are simply wrong and over complicated.
    "Doubt is the origin of Wisdom" - Rene Descartes
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  94. #93  
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    Quote Originally Posted by Waveman28
    Quote Originally Posted by DrRocket
    Whether it appears absurd to you or not is totally irrelevant. What I have described to you is the content of the best available physical theory, in this case quantum electrodynamics.

    If you simply want to reject modern physics then confine your delusons to Pseudoscience. They have no place in a physics forum.
    I'm not saying that you are wrong in terms of what Quantum Electrodynamics describes, clearly you know the theory very well. What I'm saying is that the theory itself is flawed.

    In science at present, we know about virtually all properties of the universe, we just are yet to explain them properly. I completely agree with all observations made in physics, it is just the explanation of them which I know is wrong. For example, we know that we cannot know the position and momentum of an electron simultaneously. However, explaining this phenomenon is where there error has arisen. Heisenberg thought that this was because an electron could be in multiple positions at once and that its wavefunction could collapse. That is not a sensible or logical explanation. I admit perfectly that the momentum and position of an elecctron cannot be known simultaneuosly, but for a much different reason than heisenbergs uncertainty principal. If we fire light at a 'particle', we give it extra momentum, so by the time the light has returned to us, the 'particles' position and momentum have changed. It is that simple. In this explanation, there are no assumptions or new creations, just common logic.

    Most areas of QM involve the use of Heisenbergs principal, thus this error is present in all of them. If something is fundamentally flawed, it can only lead us into a blind alley. The amount of errors in Physics has drastically built up in the last century, and we desperately need to revise phyisics as a whole from the start. This way, we can correct the errors of the past and arrive at a much more correct and satisfactory explanation of our universe.

    Quote Originally Posted by Janus
    What I see is someone who has failed to come to grips with what modern Physics has to say, and who's ego is too large to allow himself to admit that that failing might be his. Therefore, he tries to force the universe to fit within the limits of his own intellect.

    That being said, Any problem you personally may have with presently accepted physics belongs in the New Idea and Hypotheses forum.
    It is not that I do not understand Physics, it is that I understand that many of the theories in Physics are wrong. I have a very good understanding of modern mainstream physics, which has allowed me to make an informed decision about it, and I have come to the obvious and sensible conclusion that many explanations in Physics are simply wrong and over complicated.
    Your position is not one of understanding at all. it is in fact a position of not understanding that you do not understand.

    You admit to the validity of the experimental evidence of physics. Current theory is very good at predicting the outcome of such experiments, and that is the measure of validity of a physical theory.

    While it is true that physics proceeds as series of successive approximations, it is also true that each step augments and refines the preceeding steps and does not contradict them.

    The current models of physics are extraordinarily accurate. They predict the outcome of experiment to great accuracy.

    While those laws, QED included, are probably not the final laws, they are very good. It is an expression of total misunderstanding to say that they are wrong without providing an alternative that is equally accurate within their known domain of validity.

    So, if you claim that quantum mechanics is wrong it is up to you to put your money where your mouth is and propose and defend a better model.

    We are waiting. Please provide all relevant details and complete mathematics. Failing to supply this new model you simply prove that you don't know what you are talking about.
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    Just to clarify a point here, but the only way a scientific theory can be wrong is if you can perform an experiment that disagrees with the predictions made by that theory.

    At the scale of the very small, all observational evidence that I know of conforms to QED to within our ability to measure it. On the scale of the very large, all observations conform to GR. Unless you can provide an experiment that disagrees with one or both of these, you can't say either is wrong.

    Finally, even after you provide that experiment, you still have to find something better, or we'll just continue to use the current theories that will still work almost all the time, and like DrRocket said, something better includes all the relevant math.
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    Quote Originally Posted by MagiMaster
    Just to clarify a point here, but the only way a scientific theory can be wrong is if you can perform an experiment that disagrees with the predictions made by that theory.

    At the scale of the very small, all observational evidence that I know of conforms to QED to within our ability to measure it. On the scale of the very large, all observations conform to GR. Unless you can provide an experiment that disagrees with one or both of these, you can't say either is wrong.

    Finally, even after you provide that experiment, you still have to find something better, or we'll just continue to use the current theories that will still work almost all the time, and like DrRocket said, something better includes all the relevant math.
    It is quite probable that both QED and GR are wrong. For one thing they are mutually incompatible, one being stochastic and the other deterministic.

    That is nothing of particular concern. Newtonian mechanics is wrong too, and Einstein put the nail in that coffin.

    But "wrong" in physics does not mean discredited. All physical theories that have been developed so far have reasonably well defined domains of validity. All are excellent predictors of experiment withing those domains of validity. When new theories are developed to replace old ones, they extend the theories of the past, and open larger domains of validity. This is commonly called the correspondence principle.

    So there is a huge difference between saying that a theory has a limited domain of validity (philosophy "wrong" but practically correct) and declaring that a theory should be abandoned for some reason unrelated to its ability to predict the outcome of experiment.

    What has been very clearly demonstrated by the outrageous success of quantum electrodynamics and general reltivity, both of which successfully predict observations that are very strange when compared to everyday experience, is that nature does not obey "common sense" rules and that rejection of such successful theories is not a sign of logic on the part of he who rejects them but rather a sign of ignorance. It is not logical to reject that which agrees with objective measurements in favor of that which agrees with unfulfilled expectations.

    In short, "common sense" and intuituition are pretty worthless substitutes for real experimental results.
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    It,s fine with me if you see the foton as just the particle character of light (instead of a quantum of light and thus as light) But in vacuum how can the light as well as the photon then have a speed C if the wave character comes with it. As I said the times I was drunk and moving as a wave-particle my running speed could be as high as ever but going from a to b I progressed much slower. I couldn,t succeed in getting them both the same.

    Some here remind me (in the way they look at fysics) of people who admire a painting in a museum : "look what a beuatifull nude or landscape" Or "look at that light " where just see linseed oil, pigments and canvas" no matter how beautifull and truthfull the painting can be made.
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    Forum Radioactive Isotope MagiMaster's Avatar
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    What exactly is your definition of "a quantum of light?"
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    In the sense of the smallest part where you can still speak of wavelength, color, frecquency, energy etc. Like an atom is for a specific substance. If you go further you can,t speak of a molecule any more. If you go further with light you could still speak of a quantum but not of light and thus not of a lightquantum. That seems a simple logic that lies in the meaning of the words. Discussing there would come easily to discussing the meaning of words. That can be done but it is rather stupid when you think it is a discussion about content (as words can have different meaning in different contexts or used by different people you can get endless discussions and misunderstandings).

    The word foton is a good example for this. Sometimes you find it used as another word for a "quantum of light" thus having a frecquency and wavelength which makes it impossible to be "a point".

    Or it is used as referring to only the particle character. Only the particle character the photon can't be a quantum off light off course that would do no justice to the wavecharacter of light. So to become light the wavecharacter must be added first.

    Then you come to the problem of the drunken particle that has to follow a wavy pattern because light is supposed to have a wavecharacter also.
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    Quote Originally Posted by Ghrasp
    It,s fine with me if you see the foton as just the particle character of light (instead of a quantum of light and thus as light) But in vacuum how can the light as well as the photon then have a speed C if the wave character comes with it. As I said the times I was drunk and moving as a wave-particle my running speed could be as high as ever but going from a to b I progressed much slower. I couldn,t succeed in getting them both the same.

    Some here remind me (in the way they look at fysics) of people who admire a painting in a museum : "look what a beuatifull nude or landscape" Or "look at that light " where just see linseed oil, pigments and canvas" no matter how beautifull and truthfull the painting can be made.
    A photon is a particle. Period.

    "Wave-particle duality" is a misconception. Go watch the Feynman lectures in the sticky thread "Physics Lectures on (QED)"
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    If I want to call my cat foton at least one foton is a cat.
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