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Predicting the future is easy, if you are a physicist. Break a glass, and you can boldly assert that it will fall into a number of shards, assuming you know the initial conditions. Knowing the past is more difficult – you need to store much more information to piece a pile of broken glass back together.
This “causal asymmetry” makes it easier to determine cause and effect and thus place events in order. But it doesn’t exist in the quantum world, say Mile Gu at Nanyang …