Retrograde time is forward time which has passed the turning point; then as it turns back it is freighted with the load of accumulated knowledge. It is information rich. Logically, then, in its retrograde tracking, it would divest itself of its knowledge: teach rather than learn, so that when it arrived at the other end, it would be information poor, even info empty.
Philip K. Dick, The Exegesis of Philip K. Dick
big-bang, big-crunch, esp, evolution, future, radio, signal, singularity, time