Why the Universe Began with Low Entropy: The Initial Entropy Problem from Wave Information

The second law of thermodynamics requires that the universe began in an extraordinarily low-entropy state. At the Planck time, the entropy was 34 orders of magnitude below its maximum possible value today. Why the universe started so far from equilibrium has no explanation in standard cosmology.

The canvas model shows that the low initial entropy is not a puzzle. It follows directly from the wave information postulate. The information capacity of the observable universe is bounded by the cosmic horizon area. At the Planck time, the horizon was tiny—of order the Planck length—giving an information capacity of only about 10 bits. The maximum possible entropy was correspondingly tiny.

The universe was never far from equilibrium. It has always been near its maximum possible entropy for its horizon size. The apparent discrepancy of 34 orders of magnitude comes from comparing the entropy at the Planck time to the maximum entropy today—a comparison that ignores the fact that the system itself has grown enormously.

The second law is not a descent from a mysteriously ordered initial state. It is the natural increase of entropy capacity as the horizon expands. The arrow of time, the flatness of the universe, and the low initial entropy all follow from the same principle: the finite information capacity of the cosmic horizon. No fine-tuning required.