The ability of the universe to oscillate is dependent upon a certain critical mass. This critical mass is required to slow the expansion of the universe and force a contraction. If this total mass is not present, which seems likely, then the universe will continue to expand into eternity. Even if there were enough mass to cause the universe, the result of that collapse would be a "Big Crunch" as opposed to another Big Bang. The reason that the universe would not "bounce" if it were to contract is that the universe is extremely inefficient (entropic). In fact, the universe is so inefficient that the bounce resulting from the collapse of the universe would be only 0.00000001% of the original Big Bang (see table above). Such a small "bounce" would result in an almost immediate re-collapse of the universe into one giant black hole for the rest of eternity.