There's a paper here http://xxx.lanl.gov/abs/astro-ph/0507619 that says they used general relativity to explain galaxy rotation curves without needing dark matter. It's from astro-ph, so I guess it's not woo woo and has too much math in it to be woo woo. Did anybody know about this paper? Had any errors been found in it or is it the unfounding of dark matter?