The document summarizes problems that emerged with the Big Bang theory starting in the 1970s-1980s. Observational evidence showed:
1) Galaxies rotated too fast based on visible matter, implying 90% of matter is "dark matter".
2) The cosmic microwave background was too uniform across distances light could not have traveled, the "horizon problem".
3) The universe appeared "flat" requiring impossibly precise conditions shortly after the Big Bang.
4) Distant quasars existed too early, inconsistent with the universe's evolution. This "crisis in cosmology" suggested the Big Bang theory needed replacing.