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Re: Dip uncertainty
From: Alexandre Eremenko
Date: 2004 Dec 6, 20:42 -0500
From: Alexandre Eremenko
Date: 2004 Dec 6, 20:42 -0500
I did some calculations and obtained a result which shows that the matter is more complicated than it was suggested in our "thought experiments". In the Bruce experiment, all refraction was concentrated on one single height the height of the small observer. In this idealized case, the error (ERR) of the dip due to refraction of the tall observer is approximately ERR=err.sqrt(h/H), where err is the similar error of the short observer. So ERR is indeed somewhat smaller. (So Trevor was right in analysing Bruce's imaginary experiment!) On the other hand, when we increase H, the part of the refraction between the two guys increases, and it is hard to imagine that most of the refraction happens on a very small height. (Recall my thought experiment when H is higher than the whole atmosphere). Now, taking into account that we are only talking of the "anomalous part" of the dip correction due to the refraction, it seems that the question is impossible to settle theoretically. One needs experiments. Alex.