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In Bojowald's 2010 popularization of Loop Quantum Cosmology Once Before Time, there's a sketchy diagram (on his p.125) showing quantum perturbations in a transitional phase between contracting and expanding universes as widest at earlier times of decreasing volume, narrowing at the singularity-averting bounce, and remaining narrow in later times at smaller volumes. I've read in older books, and in some stuff on the web, that bouncing cosmologies require an increase in volume with each bounce, to absorb entropy. Consequently, it surprised me to see a depiction of the perturbations as being more prolonged during earlier times, although I'm assuming that the increase in their volume is needed to generate repulsive gravity as a response to the negative pressure associated with the contraction of matter due to cooling. I may be making a wrong assumption by figuring that the perturbations are analogous to the burbling drops in air pressure produced by Bernouilli's Principle in such situations as the passage of air over an airplane wing, but, assuming I'm not, does mainstream LQC currently see the proportion of each iteration of the universe that's occupied by the lower density portions of the quantum perturbations/fluctuations as increasing between each bounce and the next? (If it doesn't, the odd thing is that the sketched band representing the perturbations remains at constant width after its closest approach to time zero, which, to me at least, suggests a one-shot bounce rather than an endless sequence of expansions and contractions. Is some imperceptible subtlety in the post-bounce widening of the perturbations implying an LQC bypass of the BGV Theorem?)