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Light As a Wave

  1. Jun 14, 2013 #1
    I've been comparing light as particles and waves in outer space when it occurred to me, if you throw two rocks of equal weight in to a pool side by side the waves created will cancel out. Do stars In space effect each other in this way?
  2. jcsd
  3. Jun 14, 2013 #2


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    It would be HIGHLY unlikely that 2 stars would have the exact same frequency/waveform in a way such as to created destructive interference and even if it happened it would be a VERY localized occurrence (you'd have to be in exactly the right place in space to "see" it)
  4. Jun 14, 2013 #3
    Ok, I understand, so basically it's possible but to small for it to matter right?
  5. Jun 14, 2013 #4


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    Really?? :confused: You think that if you and I jump in the water together, our splashes will cancel? Not hardly!

    In the first place, water waves are very much different from light waves. For one thing they are dispersive - different frequencies travel at different velocities. Ignoring that, at best two water waves of similar frequency could interfere, meaning that they tend to reinforce each other in certain directions and cancel out in others.

    Well you might get that effect if stars emitted pure waves. like lasers do. But what they do emit instead is an incoherent jumble of frequencies and phases, which simply won't exhibit interference.
  6. Jun 14, 2013 #5
    Light can be defined as having properties of both a wave and a particle but in it wave properties it does not act similar to an ocean wave. Ocean waves need a medium to travel through(water), on the other hand light needs no medium( that is how it travels through vacuums). That being said I don't think that the waves would cancel out seeing as the don't constrict to the same rules, but that is just my input I could be wrong
  7. Jun 14, 2013 #6
    Not really.

  8. Jun 15, 2013 #7


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    right, I think this goes back to what phinds said. If you stand in the right place, they get cancelled out, but in other places they are reinforced. anyway, this does not happen for light between two start because the light is not coherent (as others have said).
  9. Jun 15, 2013 #8
    Ok, I understand now, I was mislead I thought 2 waves (in water) with equal wavelength and frequency would cancel out. Thank you all for your help!
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