I am looking for controversial subjects in physics, and possibly other sciences including math. There is a paper due at the end of my semester of english/composition and I must write on any controversial subject (so long as two sides to the issue exist, which is not very specific). ie (iraq war, abortion, etc) SO far I have come up with: Cold Fusion Free energy/Perpetual motion Qualifiying characteristics of a planet (What makes a planet a planet?) Blackholes Wormholes Riemman's Hyp. (can it be proven or not?) Big Bang (static universe?, hot?) Evolution Embryonic Stem Cell Rsrch. Are there any others left?