razimantv

Soap bubbles appear colourful in the sun in spite of low coherence because the soap film is thin. Soap films can be as thin as tens of nanometers meaning that light has to be only coherent for a femtosecond for interference to happen -- and this is very comparable to the cycle time of the light itself so that coherence is practically assured. But the round trip time in a 5mm window pane is 50 picoseconds, which is thousands of times larger making coherence important.

This treatment is missing an important thing: Sunlight is not coherent over such long distances such as window pane thicknesses. Basically the two reflections cannot even interfere in the case of sunlight because they do not have a phase relationship.

We started out trying to write a general method to convert top-down dynamic programming to bottom-up and this was as far as we got. Working around finite stack sizes and generating the topological sort of the function states are the only practical uses that I can think of.

Was more of an interesting challenge personally.

Done.