An eternal Universe where the measure of disorder (entropy) grows is, for most of its time, a homogeneous void. In it, complex structures occasionally assemble by chance, such as fleeting consciousnesses — ‘Ludwig Boltzmann’. According to probabilities, we should most likely be such ghosts rather than possessors of a long history.
A new quantum model resolves this paradox by likening the cosmos to a perfectly tuned clock. If the Universe’s energy levels are commensurate, its evolution becomes absolutely periodic. After the big bang, expansion of the universe drives matter apart, chaos increases, but the cycle ends before billions of random brains can arise. Quantum mechanics acts as a winding mechanism that returns the hands to the starting position.
In such a world, we are the natural inhabitants of an orderly phase. From the standpoint of spacetime curvature, this means the Universe has extreme values of curvature — a ‘floor’ and a ‘ceiling’ — between which it oscillates. Without this periodicity, for every genuine consciousness there would be an astronomical number of phantom ‘brains’ emerging from the void more often than we evolved.
In a strictly periodic Universe, you will one day read this text again — exactly the same, as if time had looped.
A cyclical Universe has inspired science fiction writers: in Asimov’s ‘The Last Question’, the world is reborn after heat death.