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    Re: Irradiation
    From: Bill B
    Date: 2004 Nov 28, 22:09 -0500

    > The problem with that physical model is that it involves two dark areas,
    > with some light between, not one boundary between one dark area and one
    > light one. Perhaps in consequence, I see (or think I see) the shadow
    > jump between my fingers before they touch (or before I can feel them
    > touch, which may or may not require more-than-minimal contact in order
    > to activate the touch receptors in my skin). I also think that I can see
    > diffraction patterns in the gap between my fingers before the shadow
    > jumps across -- which may simply be my defective eyesight but wouldn't
    > be too surprising if real. Shouldn't there be diffraction as well as
    > irradiation, since the two-fingers model involves a bright slot, not
    > simply a boundary between light and dark areas?
    
    Trevor
    
    Interesting. Somewhere in the beginning of this now-ten-month journey into
    cel nav I recall an astronomy (?) article about a dark "flash" that would
    "jump" between 2 celestial bodies (not at all locations or for all
    observers) before they actually touched.  Given irradiation, this seems
    strange as given human perception/irradiation the bodies should appear to
    touch before they actually did.
    
    Also, going back to circa 200 BC, it was established that a lighted sphere
    (or light source) bigger than the sphere it illuminated would illuminate
    more than 50% of the smaller sphere.  This Alex has convinced me--despite
    human field-of-view and mathematical perspective that would make an object
    appear smaller as it gets farther away--still holds true today.
    
    In photography we often use a back light in a reflector larger than the
    subject on the same axis as the lens/subject but behind the subject to "rim
    light" the subject.  Of course this has head hair and fine body hair to
    accentuate the effect.
    
    Is it possible that the finger tips, approaching small hemispheres, are a
    bit more than 50% lighted, and we are in fact experience irradiation? Or
    perhaps the same phenomena astronomers witness (which I do not have an
    explanation for)?
    
    Bill
    
    
    

       
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