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Theoretical Particles @ Planck Scale: Is there a maximum wavelength of light?

  1. Sep 30, 2011 #1
    First time poster so please be gentle...

    E = h * f
    f = c / wavelength

    1) Is there a theoretical limit on maximum f (minimum wavelength of Planck length)?
    2) Is there a theoretical limit on minimum f of 1 (maximum wavelength of c)? (ie// the maximum distance that a photon can cover in unit time?)
    2a) Are there radio waves that exist < 1 Hz?
    3) Is it possible to measure E < h ? Is this distinguishable from E = 0?


    Background: BSc in Comp. Sci.
    I've searched the forums but haven't found anything that covers this...
  2. jcsd
  3. Sep 30, 2011 #2
    1) I don't think there is a physical limit to the frequency, but there is a limit to how accurately we can measure that frequency.

    2) The maximum distance a photon can cover in unit time is determined by the speed of light, unless I'm misunderstanding your question...

    2a) Yep -- a 0.5 Hz (cycle per second) signal would have a wavelength equal to the distance EM waves travel through a given medium in 2 seconds.

    3) Yes, but I believe a corresponding measurement in time would become extremely inaccurate. I'm not sure about the second part of the question...

    Any physicists correct me if I'm wrong (I'm sure you would do that anyway).
  4. Oct 1, 2011 #3
    Hey Runner,

    First, thanks for answering.

    As to #2/#2a they're both asking pretty much the same thing.

    If an EM wave has a frequency .5Hz doesn't that mean that the wave is propagating faster then c (the particles that make up the wave need to travel at 2c)?

    Is frequency really just a continuous number or does it have some grounding and constraints in the real world?
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