| MadSci Network: Physics |
Your initial premise is incorrect - the speed of light is finite and given as exactly 299,792,458 meters per second with a relative measurement uncertainty of 4 parts in 1 billion. This is clearly described in any physics reference and is in fact described in the on-line Wikipedia reference you provide. The Fizeau experiment, like all the others, is not trying to prove that the speed of light is finite, but rather to measure the actual speed. Mathematically and physically it is impossible to have infinite speed of light. See the explanation by Stephen Reucroft and John Swain at http://www.scientificamerican.com/article.cfm?id=why-isnt-the-speed-of-lig
As a note to your question, I would not place too much reliability on the Fizeau experiment. It is one of the least reliable methods for measuring the speed of light and is used simply for demonstration purposes if at all. However it does give a rough ball-park value.
[note added by MadSci Admin: The logic of your argument is sound, because IF the speed of light were infinite then one would get light through the Fizeau apparatus as you described.]
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