Take an ocean tide. This way, that way, the tide swaps sides. That is perfectly reversible so has no time line or arrow of time. Now place an observer in the picture and they will insist on an arrow and direction of time. They make time where there was none.
Rather than try to predict the universe previous to right now and need to guess, especially to need to theorize before the start of the big bang (if there were one*). Science can not tell us the early moments so let's leave the guess and start right here with what we do know.
What we do know is that we live in a universe which is accelerating in its expansion and increasing in entropy. From that we can say that this will continue for some time along our imagined direction arrow of time and it has no good reason to decrease in entropy, size or acceleration.
The universe will then be massive and very very sparse, but at very high entropy. As expansion continues then even the most massive bodies will be minutely small relative to the universe's size.
Even now with increasing size and at increasing acceleration the entropy will 'seem' to drop. The overall size and pressure of space will render any bodies more and more insignificant to the norm state of things. We have no real say whether the massiveness of space may force solid bodies to evaporate or otherwise disappear but even if they don't the entropy would seem to drop off.
Entropy has no real reason to always increase and the nature of randomness is that from this state the next step could well be a slight contraction. From this all of the energy in space and any little bits of matter (little relative to the size of the universe even if vast by our standards) would accelerate "inwards". This would lead inevitably to a small point of intense energy, initially quite high in entropy but reducing to a tiny dot of near or true zero entropy.
Then boom! Expansion and increasing entropy. And in all of the random possibilities, "hello!" the universe would be as we see it now. Tao, somewhere in the early middle of the Yin Yang cycle would sit on a train on a smart phone and write this.
* Note I do not need to say a big bang existed but instead reach a place where I predict there will be one and from here I result in a cyclic, fully reversible theory not dependent on a linear time arrow.
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