Incorrect - you cannot produce a rainbow indoors with a strong lamp and a shower head - you need a mirror too.
And if the Rainbow is cause by the refraction of sunlight in a raindrop - there should be millions of tiny rainbows in the sky, but we see one solid 2 d rainbow.
And while light may refract though a raindrop, water droplets do not reflect light - I dont think you understand the difference.
So while it is a "theory" id categorize it as bs "excuse theory".
Undeniable proof - pretty much - but I'm sure you find a decent excuse or find another word you dont actually understand
http://www.youtube.com/watch?v=GoAt2BhyoCE
Not that this has anything to do with Rainbows in particular, just wanted to point out that Einstein wasn't a confirmed Heliocentrist as some think.
https://pbs.twimg.com/media/CoZnO_wXYAELRTL.jpgYou've never had a garden hose produce one in the summer, must've reflected off the dome