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Whether light emits the same amount of energy when it is in waves

  1. Jul 15, 2010 #1
    I have a doubt. I need to know whether light emits the same amount of energy when it is in waves as well as particles? Does light coexist as both waves and particles. For sometime as waves and sometimes as particles? Am an computer science engineer working in a company. I have a huge passion for physics, so dont mistake me if my question is stupid?
  2. jcsd
  3. Jul 15, 2010 #2


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    Re: Duality

    You might want to start by reading the FAQ thread in the General Physics forum.

  4. Jul 16, 2010 #3
    Re: Duality

    Q. If light is a wave it should spread out evenly over distance, although the signal would be weaker because of the dilution the light would reach every place.
    But if light is a particle then as it spreads out from the source a certain amount of distance would grow between the particles as they are increasingly further from the source, they would be scattered over a greater distance.
    A. This morning I was listening to the radio on my mobile phone, and I noticed that in one particular spot I got no reception at all, and just a few inches away I got a perfect reception!
    I discovered that there is only a single antenna transmitting this channel and so there was no reason to suspect interference in the waves!
    This to me is the best most simple proof the light is particle based.
    Using photometer's one could assume that the energy in the wave was enough to release the electrons and it could theoretically be argued with as a proof of the particle nature of light.
    But does anyone see any problem with my radio experiment?
  5. Jul 16, 2010 #4


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    Re: Duality

    And there were no buildings or other large objects to reflect part of the signal? If you were indoors, walls can have the same effect.
  6. Jul 16, 2010 #5
    Re: Duality

    nope it wouldn't make an interference pattern as the reflections only make a quarter shift in the wavelength and would not cancel out the signal entirely like in an interference pattern as they are not opposite waves when reflected. If they would cancel out then it would not produce an interference pattern because of the photons reflected just once.
    BUT, either way the test is outdoors in a field, with a single transmitter.
    Has this not been tested by someone else already?
  7. Jul 16, 2010 #6
    Re: Duality

    OK so we understand the behaviour from the beach, but in the beach the wave is still water (matter) - isn't light just the wave of electrons in the earth coupling and decoupling with photons, and this obviously spreads out as each coupling event is happening at random and although the light is a photon in between electrons it is also a wave in the fact that it is a message moving through another medium (the electrons) just like a wave at sea is a wave being transmitted through the medium of water?! What is wrong with this.
    And this is why Richard Feynman is forced to say that the vacuum of space is really filled with constantly appearing and disappearing particle-antiparticle pairs, so that antimatter can be used to absorb and then retransmit the photons so that we can get light from the sun, stars etc.
    And when Einstein saw that light bent around the moon, he was observing the gravitational pull on the electrons that were coupling and decoupling from the photons.
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