: I would like to get some opinions on dark matter. Weather or not it exist, what its comprised of... etc. I tend to lean twords the theory that the Universe expands and contacts and seeing as that theory is not possible without some other type of matter to cause the colapse, im very insteresed in dark matter.

i've just recently come a cross this facinating theory, so i would restrict my answer to this: http://cossc.gsfc.nasa.gov/gamma/new_win/nw5.html http://cfpa.berkeley.edu/group/directdet/pubs/sadoulet_lecture_nov95/dm1.html