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Constant limit c restricts photons to radial observation

  1. Dec 30, 2003 #1
    We observe light only radially due to its constant limiting speed for all frames of reference in vacuo, and undefined immediate relativity (indistinguishability) between photons. We infer matter otherwise - both with radial and orbital motion - by emitted light frequency shift, apparent motion and interaction.

    This comparison suggests a corollary to Einstein's constant light speed postulate: real photons in vacuo radiate only inwardly through spacetime to converge upon the observer, with complete certainty.
     
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  3. Dec 31, 2003 #2

    mathman

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    You seem to confusing all photons with those we happen to see personally. Those you see come at you radially. All others don't. They all travel at c in vacuum.
     
  4. Dec 31, 2003 #3
    mathman,

    How can we interpret, primarily or secondarily, that nonradial photons exist? I'm trying to establish that the constant light speed c in every reference frame is equivalent to observation of exclusively radial photons.
     
  5. Dec 31, 2003 #4

    krab

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    Been thinking about this post and decided I don't understand any of it. So I'll read along till I hit the first thing I don't understand. What is meant by observing radially? As opposed to what? Tangentially? Azimuthally? You mean we don't observe light that passes in front of us without hitting our retina?
     
  6. Jan 1, 2004 #5
    krab,

    What I am saying is that our knowledge of photons not impinging directly upon us is totally uncertain, a corollary of both postulates of relativity: constant, limiting in vacuo light speed c and unchanging physical laws among inertial frames; and likewise, plural application of Heisenberg uncertainty.

    Take Feynman diagrams for instance. For other than first order (impinging) photons, an observer has predictable only probabilities and thus expects totally random directionality of light. Physical laws and light speed each are observed similarly from corresponding inertial frames since radially isotropic (first order) observation entails a spherical symmetry.
     
  7. Jan 1, 2004 #6
    Re: Re: Constant limit c restricts photons to radial observation

    Hi Krab,
    I believe Loren means "radially" with respect to the light receiver and not the light source. E.g. your eye sees the total lunar or solar disc but only those photons, emanating in a conic package with your lens as the apex and the disc as the cone's base. Near the edge of the disc, each iota of area radiates isotropically but only those photons directed toward your lens are received - your right eye sees an entirely different array of photons than does your left eye.
    Also photons do not radiate laterally; if they did it would result in a loss of energy - increased wave length. You cannot see a laser beam from the side, what you see are dust particles that absorb the energy and rebroadcast, isotropically, slightly red-shifted photons.
    Cheers,
     
    Last edited: Jan 1, 2004
  8. Jan 2, 2004 #7
    I read tonight in the recent Gleick biography on Newton that Descartes' vortices would predict nonradial light propagation in vacuo (as he interpreted it).
     
  9. Jan 2, 2004 #8

    ahrkron

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    Can you please define, as precisely as possible (and as simply as possible), what you mean by "radial propagation"?

    So far, I thought your use of "radial" was something along the lines of "directed to the observer" (or detector device), but this last post, you mentioned "nonradial light propagation" as if it could be a property of light, regardless of any observer.
     
  10. Jan 3, 2004 #9

    ahrkron

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    I'm with krab. I cannot make sense of what you mean with this...

    Do you mean that "we don't know about the photons that don't get to our detectors"?
    Why would they be any different?

    I don't see any relation between those postulates and the previous part.

    Again, I don't see any connection between Heisenberg relations and the fact that we don't know about undetected photons. Heisenberh uncertainty relations apply only to detected quanta. It relates uncertaunties in the measured properties of observed systems.

    There are first order interactions, no first order photons (or any other particle).

    Probability distributions may have some structure, which seems at odds with your statement of "totally random directionality".

    Again, what do you mean with "first order" here? It usually does not apply to "observation" (neither to "isotropic").
     
  11. Jan 3, 2004 #10
    ahrkron,

    "Radial propagation" is linear trajectories from or to a common point.

    The term "nonradial" I used only as actual re Descartes' vortices.

    We assume there are photons, or for that part, fermions which are not physically provable. The only photons, or information about other matter, that we can be sure of are those which impinge upon us radially, i. e., at all. Our picture of the universe is much like Plato's cave allegory in this regard, where only two dimensions of space experienced at each moment.

    Picture a Minkowski cone. At its vertex, the observer recieves his total light along radial lines in space, as is true locally even in general relativity. The radial spatial geometry of the cone relies fundamentally on the speed of light being constant. Likewise, physical law in a local inertial frame remaining unchanged relies upon the isotropy of the light cone.

    Individual photons removed more than one order of interaction from the observer lose all information about their position, momentum, time, energy, angular momentum and other quantum observables from our perspective.

    Wavefunction probabilities, based upon orthogonal axes, have no effect on the radial nature of light, I surmise.

    "Radially isotropic (first order) observation" can refer back to the Minkowski cone. Juxtapose two such cones at random orientations, and you can see that each additional cone adds a new (classical) "order" of photon interactions. A separation between two events of two or more paths is reducable to total isotropy relative to the initial observer. Nonclassical uncertainty disrupts a composite path when considering the single photon. Although the individual plural-order interaction photon may be completely uncertain, you are right that the total interactions themselves yield definite probabilities upon quantum considerations.[zz)]
     
  12. Jan 3, 2004 #11

    ahrkron

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    Is it a collective property then?
    I get the impression you were using it for individual photons, in which case there's no way to define a "common" point.

    Can you elaborate?

    Agreed

    Since your definition of "radially" implies a collection, I don't agree with this, since individual photons can and have been detected.

    Why? Imagine for a moment many sources, each producing some sort of waves in all directions, each wave with a different speed. If you put a detector among them, it will receive only those going "radially" towards it, regardless of the speed of the source. i.e., the radial spatial geometry of the cone is independent of the speed of the perturbation.
     
  13. Jan 4, 2004 #12
    The common "point" for observed photons is with the observer; they need not be simultaneous, but classically discrete, and together may represent an interference pattern. Upon correlating measurements we note that no two wavefronts propagate exactly parallel, and thus neither perfectly cancel nor reinforce each other at the observer - not only radial but nonparallel. The point being that we observe photons along a unique radius common to the observer in an inertial frame, due in part to universally constant light speed (see last paragraph).

    Descartes imagined an ether of vortices that determined the trajectories of light particles. Imagine photons in near-orbit around a black hole. An observer on its event horizon would perceive them locally as moving along a radius (Minkowski cone), considering the distortion of neaby spacetime. This is as close to a Cartesian vortex that I can think of as actually appears in nature. His physics were basically disproved by Newton.

    The exactness of the Minkowski cone is preserved only for particles with a constant speed. All fermionic matter eventually deviates from each other in magnitude and direction.

    Any nongravitational energy transmission can be resolved into photonic waves. So in a vacuum, the only such propagation is, by default, radial and a primary interaction "in" whatever material medium is always with "first-order" photons. E. g., electromagnetism remains unchanged despite movement between its inertial frames.
     
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