A Gravitational Origin of the Arrows of Time

Understand

The only widely accepted explanation for the various arrows of time that everywhere and at all epochs point in the same direction is the `past hypothesis': the Universe had a very special low-entropy initial state.

• We present the first evidence for an alternative conjecture: the arrows exist in all solutions of the gravitational law that governs the Universe and arise because the space of its true degrees of freedom (shape space) is asymmetric.
• We prove our conjecture for arrows of complexity and information in the Newtonian N-body problem.
• Except for a set of measure zero, all of its solutions for non-negative energy divide at a uniquely defined point into two halves.