Professor Charles Bailyn
Source: Yale University, Open Yale Courses
Omega and the End of the Universe
Omega is the actual density of the universe divided by its critical density: if it is greater than 1, there will be a big crunch; if it is lesse than 1, the universe will expand forever. Evaluating omega is not easy, partly because of dark matter (WIMPs:Weakly Interactive Massive Particles, and MACHOs: Massive Astrophysical Compact Halo Objects).
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