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Will
the expansion stop?
•Is there enough gravity (enough mass) to stop
expansion?
•Consider an simple model as first step (full model gives same answer)
–Treat universe as having center
–Assume only Newtonian Gravity applies
–Does a given shell of matter have
escape velocity? Is v > vesc ?
The expansion will stop if r is high enough (4x10-30 g/cm3).
