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Maybe photons don't exist ?

  1. May 29, 2003 #1
    every time i read about photons, I'm always given one of two perspectives.

    1: they are energy packets, [containing mass], and when falling below lightspeed, they switch from a 'plasma like' state to a solid state.

    I have also heard opposing theories that photons don't contain mass, which allows them to move at light speed without having an apparent infinite mass. Thus when these same energy packets reach less than lightspeed velocity, they cease to exist.

    In some aspects, it has been said that photons do not have mass, yet there are many ideas about Solar Sails to capture this minute momentum, and a few thousand essays on the concept of 'radiation pressure'.

    Although I've seen mathematical equations constructed with (energy equals 1 + (blah blah x^y), I do not choose to believe these equations, especially since the margin of error with such experiments always renders the (1+ ...) irrelevent.

    2: Energy waves. I have heard that photons were assigned a physical form for the sole reason of being able to travel in wave form, through vaccum, since a vaccuum can't "wave", since it doesn't exist. This again, to me, seems like someone trying to cover a mistake, much like a grade schooler adding a line to turn a D+ into a B +, and most importantly to me, it feels "wrong".

    If there is an aether, and you may feel free to call it spacetime, to avoid feeling confused, then wave propagation, or whatever they call it today, is possible. Ligh, in this aspect, could be a wave, like a wave in jello, or a wave in water or air.

    This may seem far fetched, but Popular Science (in the last 2-3 years), began discussing a recent (not brand new) invention, which allows sonic pulses to be compressed into beams, or cone, much like a laser beam, and have practical applications for weapons and grocery store advertising. I do not claim to know or remember exactly how they did this, but I think they could do the same thing with an EM wave in spacetime.

    In this regard, it seems ot me that a wave compressed into a stream, could appear to be a particle stream, but would merely be another wave, with no mass, having properties of both particles and waves, and still not having mass, or speed limit.

    3. Then it occured to me yesterday, that a photon may infact be a particle, but the particle is not travelling through nothing, it is travelling through a substance, like a bullet through jello. This could be creating a disruption, or "wake", behind the photon, constituting waves, which would be like a speed boat's wake.

    It also occurs to me that a photon may "burn out" after 20 billion lightyears of travel, or something similar, and the aether may be so thin, that our instruments cannot measure the difference accurately as in the michael-morely experiment.

    And of course, this whole idea gets confused when they speed of light seems to jump x 1000,000, according to some rather skeptical NASA researchers (do a google search "NASA faster than light" for more information)

  2. jcsd
  3. May 29, 2003 #2


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    "Reality is that which, when you stop believing in it, doesn't go away."

    - Philip K. Dick
  4. May 29, 2003 #3


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    The idea of radiation pressure came around before the idea of a photon. You could deduce that light had momentum solely from the Maxwellian theory of light.

    In Special Relativity, the very definition of momentum demands that any particle travelling at light speed have zero mass. In SR, mass is proportional to the magnitude of the momentum 4-vector, and the magnitude of the momentum 4-vector is 0 for anything with a light-speed trajectory.

    In Quantum Mechanics, it was determined that the average position of a wave packet behaves as if it was a particle travelling at light speed that had momentum equal to that of the wave packet. Thus, it is convenient to label the wave packet as a photon and treat it as a particle.

    In an electromagnetic wave, what "waves" is the magnitude and direction of the electric and magnetic field vectors.

    The speed of light is always c; it never changes. What can change is what we measure when we try to measure the speed of light.

    For instance, one "obvious" way to measure the speed of light is to mark the times at which it passes two points in space and divide the distance by the time. However, if for some reason the light gets interrupted (say... an electron absorbed the photon and then reemitted it), our measurement of the time includes those delays where there was no actual photon moving around, so we'd measure a reduced speed of light.

    Another way to measure the speed of light is to watch how fast the crest of the light wave is moving. The problem with this is that somewhere during the travel, the light may phase shift. The phase shift affects the progress of the crest of the wave, so while the light may be travelling with a constant velocity, the crest may be travelling at a wildly different speed.
  5. May 29, 2003 #4
    So there i was counting beans.. and I counted 2, 3, 4 ,5 beans.. then i concluded that I should only count beans that were red, so I counted 4, but then i decided by dividing one bean by two beans I could get half a bean.. but wait.. how did I divide one bean with two ? wouldn't it make more sense to separate two beans with 1 ? wierd huh ? so I decided to call this "Not so special Bean Relativity" and I can clearly demonstrate this theory with beans.
  6. May 30, 2003 #5


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    Great quote.
  7. May 30, 2003 #6
    Hurkyl, what is carrier for 'fields' in physical reality? I'm always confused by how 'obvious' its assumed. All I've seen is that its just convenient equations. Now that vacuum isn't empty, and spacetime itself must be quantified, is it correct that any field is infact result of concentrial layers of excitations of closest vacuum spots?
    If so, then photon isn't necessarily moving at all, just excitations of vacuum propagate, somewhat like sound waves. Energy is delivered, but no rest mass is meaningful. Is this sensible view?

    Speed is always distance/time, ratio. Spacetime itself manifests through planck time and positional uncertainty. So if, together with change in c, time and thus also measure of distance changes, what chance we have to detect change in c at all? Makes me think that if vacuum spot excitation changes ratio of planck length/time, this isn't necessarily detectable as change in c, but change in size of section of space, ie curvature.
    I know its damn layman view, but are there any even remotely corresponding ideas in science?
  8. May 30, 2003 #7
    I was hesitant to open thread

    but your quote made it well worth while.
  9. May 30, 2003 #8

    Electromagnetic waves ("waves" is a better term to use than "fields" in this case) require no carrier, that is, the wave propogates through free space; matter is not necessary for propogation. Free space has it's own physical attributes, i.e. permeability, permittivity, temperature, speed of electromagnetic wave, etc.

    I would say average speed is always distance/time. For example: if you throw a ball, it bounces against a wall back to you and you catch it a second later at the same spot you released it, the position hasn't changed so average speed = distance/time = 0 feet/1 sec = 0 ft/sec. But the ball was obviously moving. You need to use dx/dt for the instantaneous velocity.
    The constancy of c is an assumption that has yet to be proven false.

    I'll let hurkyl or someone comment on the rest.
  10. May 30, 2003 #9


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    To complement J-Man's response, fields can also be considered as an abstraction. A force field is (to simplify things a little) simply a mathematical representation of what would happen to a particle if it happened to be at a point in space.

    When we say that the electric field is oscillating at a point x, that can be reinterpreted to mean that if there happened to be an electric charge at point x, it would feel an oscillating force.

    So, taken from this perspective, an electromagnetic wave doesn't need a medium to travel; all it requires is that the underlying electromagnetic force has some way to exert a force on a charge in some point in space (it doesn't matter what that way is).

    As for the rest of your post, *shrug*.
  11. May 31, 2003 #10
    Thats not an issue, I understand that ok. Its just mathematical equations.

    But it does matter. So far it seems that its postulated that wave doesn't need medium, because we only describe how it behaves within abstraction we call fields. But to exert force in any pos in space, something must be what exerts that force. Field? But its itself abstraction of something.
    I understand that we don't *need* medium to describe behaviour. I'm just confused to hear that therefore there IS NO medium to seek for. I can't accept that easily. Thats why I ask what is carrier for 'fields' in physical reality, not models? This is one of known, unknown, or not dealt with as you seem to imply here. I want to get a glimse on what you think is underlying fields.

    why shrug? its compressed. If its crap I want to understand my misconceptions.
  12. May 31, 2003 #11
    it is a simple thing for me really, in discussing jello.

    A wave can certainly, even if "electromagnetic" be the motion of a medium. A Particle moving through a medium can definitely leave a wake, creating waves.

    but scientists who believe (and there are many) that an object can travel through non existant volume (called vacuum) and still create waves, or more perversely, that waves with no mass/substance, can exist, without a medium to disrupt, are fools.

    The world is not flat, people.

    (now expecting peoples highschool and college rants pointing to mathematical theories that falsely prove their long established anti aether theories--- too bad too, these references are meaningless.)
  13. May 31, 2003 #12


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    This is completely wrong. It's not about objects travelling through mediums to create waves, it's about the particle of the photon being a wave packet of two fields. You might like to note that we have never detected a "wake" of waves, but instead seen repeatedly that the "particle" itself exhibits wavelike properties. Fields can travel through a vacuum. Maybe instead of just asserting denials, you might like to point out why one of the following is wrong.

    Fields travel through a vacuum.
    Varying magnetic fields can induce electrical fields.
    Varying electrical fields can induce magnetic fields.

    If not, well, your belief seems rather irrational doesn't it?
    Last edited: May 31, 2003
  14. May 31, 2003 #13


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    The reason I said it doesn't matter is because we can discuss electromagnetic waves without knowing the underlying "reality" that generates the electromagnetic field.

    So, for the study of electromagnetism, we do not need to worry about the "root cause" of the phenomenon... we'd leave that for more fundamental physics to discover.

    I have no informed idea based on hard evidence. If you want to know what my preferred speculation is, though, I think that the universe is a giant graph and that each node has some quantities associated with it, and that fields are simply the measurements of those quantities.

    This shrug meant that I don't think I could really say anything informed on the rest of your post. I must have been sleepy at the time, though, because re-reading it gives me some ideas, though.

    From what I've read, I think that the classical picture of the emission of an expanding symmetric shell of electromagnetic energy doesn't hold in quantum mechanics. The energy tends to be somewhat localized (about one or more points). Since a photon is essentially defined as the average of a localized packet of energy, then photons really are moving.

    If we carry with us a ruler, we would be able to observe that the ruler's measurements are no longer in agreement with that performed by using time and the speed of light.
  15. Jun 2, 2003 #14
    So, from this I realise that we "don't know", and because we can get away without knowing, "we don't care" for time being. And your previous statement "electromagnetic wave doesn't need a medium to travel" isn't actually what you meant, you meant more like "electromagnetic wave doesn't need a medium to describe its travel"

    Graph. Do you take view as Alex does, that its all just manifestation of something abstract like math or geometry?

    I'm getting impression from all I've read that it all comes down to essence of vacuum, and all observable is different excitation states of vacuum spots and interactions between these spots. All else being abstractions useful for modeling and testing.

    Well, tornado also moves. When you hit a nail on the head, shock energy also moves. Bet we could measure that in photons. This all makes me visualise photon as something complex instead of fundamental particle. Like water bubble in weightless spaceship, wobbling due to forces of surface tension and internal molecule and mechanical energy movement.

    Thats most interesting part. Begs few questions: how do you measure ruler? How you know that ruler doesn't change with c? See, 'c' is our fundamental etalon of measure, and physics. If c changes, all our rulers change with it. So, as long as we are within the section of space where c is variable, we have no means to detect change in c, in principle. When we compare different sections of space where c is infact different, then, if we define c as constant, we detect either change in timeflow or change in space dimensions like length. Similarily, if c is indeed constant, but timeflow fluctuates in microscopic domain, on macroscopic scale we can only detect fluctuations of spatial properties, like position, length. And we get 'the average of a localized packets of energy'.

    Basically I'm questioning idea that we could even in principle detect change in c. On large scale, its accounted or hidden by SR. On small scale, we don't have any better reference than c itself.
  16. Jun 2, 2003 #15


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    Well, we may know, I just don't know Quantum Field Theory so I don't know if we don't know. :smile:

    Not in the way he presents it. I don't think mathematics gives rise to the universe, I just think that the most accurate topology for studying the universe should be a graph instead of a differentiable manifold, or even a lattice.

    Well, from one perspective, the constancy of the speed of light is reliant on measuring devices remaining consistent with each other as you move them around the universe. My idea of bringing the ruler with me was not to measure the speed of light, per se, but to measure other rulers; to make sure that they all still measuerd the same distances. You could do the same thing with clocks.

    General Relativistically, one is always free to change their coordinate chart by rescaling their axes, and the laws of physics must still remain valid. The constancy of light is thus represented somewhat differently in GR: instead of saying it always travels at the same speed, one says it travels along null geodesics, and be done with it.

    The constant speed of light is recoverable in GR by the definition that (and I'm probably using the wrong term here) inertial reference frames are coordinate charts that locally look like Special Relativity, and in SR, null geodesics are precisely the (classical) speed c trajectories.

    Is it "cheating" to do it that way? Maybe, but we do other physics in SR, and a SR-like frames exist everywhere, so we might as well do it that way.
  17. Jun 2, 2003 #16
    understood. My point though was exactly that you can't make a ruler thats independant from local speed of c. Thus, if you take it with you, it will match any rulers there, even if speed of c actually differ in these two reference frames. Take those same laws, any physical processes. At some level they all depend on 'c', size of atoms, their energy, speed of processes, etc. Thus any ruler depends on that too.

    You mean, it follows curvature of spacetime? And curvature depends on E=Mc^2.

    Do you talk about apparent constancy of 'c' when going from one reference frame to other?

    Well, I'm thinking about 'c' within reference frame. Imagine that you are god :smile:, and that you have ruler independant from anything, so that you can compare our rulers. Now you can see that our ruler in our reference frame is say 1km long, and when we move it to other reference frame where 'c' is slower, it becomes shorter, while in open space it was longer even. But we, who don't have independant ruler of god, don't know that. For us, moving from one reference frame to other is moving from one gravitational curvature to other, where in any such frame all processes flow equally. And our only reference of measure is actually that local speed of 'c', thus although the rulers are different for god, they seem exactly same for us.

    We have no means to construct such a ruler that we could detect changes in 'c'. Together with 'c', geometry of spacetime itself changes along with it, laws. Whole our existence is defined through 'c'. Thats why all reference frames are equal. Constancy of c and that all reference frames are equal are axioms, but isn't it that all reference frames are equal because we have no means to detect inconstancy of c?
  18. Jun 2, 2003 #17


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    We don't need to use God's ruler; we can simply invoke our General Relativistic right to change our coordinate system. For instance, I can switch to a coordinate chart where all distances in one particular direction are doubled, and then light going in that direction would be measured to have classical velocity of 2c.

    (I'm not really sure how to continue from here, atm)
  19. Jun 3, 2003 #18
    Seems you still don't get what I'm trying to say. You can switch to another coordinate chart for the room next to yours. That isn't physical change in c, and it departs uniformity of spatial dimensions.

    I'm trying to say that if c really physically changed in one direction more than any other, you wouldn't be able to *physically* detect that by any means. You'll feel uniform space and constant c. Reference to 'outside' should appear not as change in c, but as change in curvature of space.

    Do you agree with that? Or is there any method to determine speed of physical c without any spatial motion at all?
  20. Jun 5, 2003 #19
    Probably not, (begs the question, no spatial motion relative to what?) but you could use an interferometer in seperate reference frames, that is different velocities, and compare the results. Has this been tried? i.e. Measure in Earth-lab (done), and measure on space-station, satellite, or interplanetary probe?
  21. Jun 6, 2003 #20

    as posted in the 1 particle many universe theory, ive been thinking..

    Is it possible that spacetime/aether is the only solid, but that solid is wavy like jello, and malleable to a degree, in reference to itself ? and let us suppose for instance, that not only all waves were waves, but all matter were also waves, except we were failing to percieve ourselves as waves because we desire to feel solid ?

    in essence, what if all matter were a vibration or wave, and even when dispersing, that wave transforms from one thing to another, but in any location of aether, a wave can cease to exist, and re-exist by travelling.. it would also be possible to have a carrier wave travel so fast with such a huge ripple, that it would pass over other waves with seemingly no disturbance, almost "teleporting".

    And if everything, incuding matter, energy, light, sound, -- was all wave,s then lightspeed would be irrelevent... Teleportation would be possible, but time travel would require the warping of spacetime, which would be much much harder than creating a shock wave.

    Perhaps also (i have no clue on this one, i just devised it today), there is some kind of relationship between these "matter waves", light waves, sound waves, and aether ? Perhaps there is a "matter-energy-wave" conversion ?
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