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What is Light?

  1. Nov 15, 2003 #1
    What is Light?????

    What is Light? Is it a EM wave or a stream of photons? Is there any theory which can explain all the phenomena of light?

    P.S.: Another question, What makes glass transparent?
     
  2. jcsd
  3. Nov 15, 2003 #2

    Integral

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    I'll bet that with a bit of reading in this forum you will find 10 different threads which ask this same question or something similar.
     
  4. Nov 15, 2003 #3
    Or read Richard Feynman's 'QED' book for all your answers. :smile:
     
  5. Nov 15, 2003 #4
    light has a dual property it acts as particle under some conditions and as a wave under some conditions.

    but.......

    please dont take this as some theory or anything like that this is just my hypothesis i believe that light acts as a particle in magnetic or a electrical field. look at an electron when it absorbs light it has a electrical field around it.

    If i am wrong let me know.

    -benzun
    All For God.
     
    Last edited: Nov 17, 2003
  6. Nov 15, 2003 #5

    selfAdjoint

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    I'll repeat what Adrian said. Read Feynmann's QED before you try to dream up your own theory.
     
  7. Nov 16, 2003 #6
    Light is that portion of the EM spectrum that we can detect with our eyeballs. It is both wave and particle, at the quantum level those two are not mutually exclusive.

    Glass is a material that neither absorbs or reflects light. Thus light can pass through, albeit it gets diffraction. Why glass behaves this way has to do with teh chemistry of its composition and is quite complicated.
     
  8. Nov 30, 2003 #7

    Yes. We at Model of Reality, www.ModelOfReality.org, finally have a reality-based theory for light. In this new theory, the emitters of light (mostly electrons) are modeled as tiny micropulsars (charges that turn ON and OFF very rapidly) so that light is emitted as a choppy WAVE.

    Finally, we have a theory that explains both the wave and particle nature of light. The "photon" in Einstein's photoelectric effect is actually explained by the electron's pulsation frequency reaching a forward non-acceleration resonance with the incident light wave. Once the electron's pulsation frequency reaches that of the incident light wave, the electron's forward acceleration is essentially over. The light then cannot transfer any more energy to the electron, fooling physists (and you thought Einstein was SO smart) into thinking that light traveled as particles.

    The lower frequencied "photons" in Compton's xray scattering are explained by a simple Doppler shift as the electrons retransmit the xrays while receding from the observer. It is amazing that no one has noticed before that the ejected electron velocities in Compton's experiment were exactly the velocities needed to Doppler shift and obtain the lowered frequencies seen in the experiment. (See A. Bless's "Recoil Electrons From Aluminum", Physics Rev, Dec 1927 p.871. See also www.modelofreality.org/Sect5_2.html ).

    The "photons" in the Bremstrahlung xray frequency cutoff experiments are explained using Nyquist's point of view. Electrons pulsating at a certain frequency v cannot emit radiation with a frequency of more than v/2. The easiest way to understand this is from recording digital audio. The sampling frequency for digital audio is 44 kHz. This 44 kHz sampling frequency is used so it possible to record the audible frequencies from 0-22 kHz. (see the literature on the Nyquist frequency. See also www.modelofreality.org/Sect5_3.html ). Thus, when an electron that is pulsating at a certain frequency v strikes an aluminum plate, this electron can emit all frequencies up to the the limiting frequency v/2.

    The usual explanation for the xray Bremsstralung cutoff frequency is that all the electron's K.E. is completely converted into a high frequency xray "photon". This seems unlikely because this limiting frequency is emitted in all directions, making conservation of momentum impossible, especially for "photons" emitted at 90 degrees with all the kinetic energy. (Why hasn't anyone noticed this discrepancy before?) With the our pulsating model, the limiting frequency would be emitted all directions, thus avoiding the 90 degree momentum paradox.

    The wave nature of light is just as one would expect, except for that the light transmitted from a single electron would be choppy, and Coulomb's and Maxwell's relations then would then only be true for macroscopic averages.

    Want more? We have given a reality-based explanation for essentially all key "photon" phenomena. We have also proposed Photon Killer Experiments to prove this theory. (Put up or shut up, isn't that what they say?) See www.ModelOfReality.org for more info.

    Now that a model of reality exists, this question is much easier to answer! We are taking light to be a wave, not a particle. We also have shown that planetary atoms are possible to imagine with pulsating particles! (See www.ModelOfReality.org/Sect6_1.html). Thus, transparency is explained by simple resonance conditions. If the glass does NOT contain atoms that have orbital frequencies that match that of the light, then the atoms in the glass will NOT resonate and rebroadcast the light with phase shifts that tend to cancel the proceeding wavefront. However, take GREEN glass, for example. This glass has atoms that have electrons that orbit with RED and BLUE frequencies, but not GREEN frequencies. Thus, the RED and BLUE wavefronts are canceled by the phase-shifted rebroadcast of these frequencies. The GREEN light passes through because there are no atomic electrons near this orbital frequency.

    This may be easier to understand if one thinks about how ceilings and walls are transparent to cell phone transmissions. Cell phone usually transmit at say 800 mHz. Obviously, one would not expect there to be 800 mHz atomic frequencies in bricks and sheetrock. Therefore, cell phone transmissions go right through bricks and sheetrock just like light travels through glass.

    However, metals are different. Metals have free electrons. Both light AND cell phones cannot penetrate metal, because the free electrons in metal can vibrate with just about any frequency of light/EM emission, and these vibrations would have the necessary phase shifts to cancel most wavefronts that tried to travel through it.


    Andrew Gray

    Any comments would be appreciated:

    andrewgray AT modelofreality.org
     
  9. Dec 1, 2003 #8
    Nice website and interesting "theory". Maybe you should post it in the debunking section of the forum? I especially like the series of killer-experiments that you propose. (By the way: the neutrino one has been done. It's result is incompatible with your theory.)
     
  10. Dec 1, 2003 #9
    OK, I'll look into that section. Good idea!


    Very interesting. To which neutrino experiment are you referring? I am especially interested to see if it involves detecting neutrinos through 150 miles of solid rock like the one in Japan claims. Can you give a reference of some sort?

    Thanks.


    andrewgray AT modelofreality.org
     
  11. Dec 2, 2003 #10
    If memory serves, such tests have been done at CERN with the neutrino beamline to the Italian site (that's also >100 km through the earth).
     
  12. Dec 2, 2003 #11

    russ_watters

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    Or start your own thread. It certainly doesn't belong here - and don't hijack the guy's thread.

    So back to the point:
    Yeah.
     
  13. Dec 12, 2003 #12
    According to Quantum ED. light is a stream of particles (only a stream, not a wave) and the wave motion represents all the possibilities of where the particles can be. I always though that light had that duality (both wave and particle stream) but after a discussion with my physics instructor who took a Quantum ED course over the summer, he convinced me otherwise.
     
  14. Jan 7, 2004 #13
    How about this:

    Photons are omnipresent - They exist everywhere.

    We live in a Universe that is actually a photon ocean.

    Information (in the form of energy such as EM etc.) is transmitted from one photon to the next in waveform.

    A beam of light is not a constant stream of photons - It is a constant information exchange between stationary photons, that we detect as a wave, and then mistakenly think it is the particle that moves.

    We have only ever measured the Speed of Light in curved spacetime!
    I suggest that the SoL is instantaneous in 'non-warped' spacetime. The photon has no age. It knows no time. The information exchange across vast distances of non-curved interstellar space is instantaneous. This suggests that the Universe is not as 'big' as we think - nor as old.

    Creationists come out of your woodwork!
     
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