Most arguments against the problem dispute that there is a fine-tuning problem (i.e. something must have forced Ω to be near 1 in the early universe) and that there is an instability problem (i.e. even if Ω was near 1 in the early universe, it is strange that it is still of order 1 today). (A notable exception is the argument of Lake which demonstrates that if λ is positve and the universe expands forever, then fine-tuning is needed in order to achieve Ω significantly different from one, a reverse of the usual (wrong) argument.) Here, I present another argument, concerning the age of the universe: our universe does not have to be fine-tuned in order to be long-lived; it is long-lived essentially because it is massive. (The usual argument is that if it were not nearly flat, then either it would have collapsed or expanded and thinned out too much before any structure could form.)
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