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    Re: Dip uncertainty
    From: Alexandre Eremenko
    Date: 2004 Dec 6, 15:58 -0500

    It is an interesting evidence that you present,
    but it is not clear what is the basis of these statements.
    I have NO experimental data. Only "thought experiments"
    Here is another one:
    Let us place ourselves into the situation
    that was already described:
    One observer is tall, his height is H and another is short,
    his height is h. Place them in such a way that they see
    the same common point on their horizons.
    So that a ray from the horizon goes to the eye of h first,
    then (through his head) to the eye of H.
    Now (this is a thought experiment!) let us remove all air
    over the eye of h. That is suppose that there is no refraction
    on the way from h to H. So the light goes straight from h
    to H.
    Then (I claim) the "refraction correction to the dip"
    for H will be exactly the SAME as the refraction correction
    to the dip
    for h.
    The ray of light is "curved" (that is changes its direcdtion)
    only on the way from the horizon to h. Then the same
    change of direction will apply at the H place, no matter
    whether H is on an aircraft carrier or on the peak of Tenerife
    on in the outer space.
    Now, if we restore the atmosphere, that is the air between h and H
    be can only get a greater correction.
    On Mon, 6 Dec 2004, Bruce Stark wrote:
    > I've dug up a couple of things that tend to confirm
    > what Trevor and I
    > believe.

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