One interesting (off topic) thing about CINAC thinking is that it breaks down in basic physics. We think of causation with an implicit forwards time direction, for example, we wouldn't say that eating a cake tomorrow can't cause it to be baked yesterday.
However, this asymmetry of time doesn't apply at the particle level where interactions are symmetric in time. An electron accelerates sideways when it absorbs a photon; later it might emit a photon and accelerates the other way, just like rolling the film backwards. When we speak of cause and effect and assume that time runs only one way but at the micro level since interactions are symmetric, causality itself becomes hard to pin down.
At the macro level things don't work like that: shattered vases don't unshatter. Heat always flows from hot to cold. Even though many individual particle collisions will transfer energy against the gradient, the net effect over zillions of of interactions is for heat - molecular kinetic energy - to always flow down the gradient.
Some physicist have looked to the micro level symmetry for an explanation of entanglement ("spooky action at a distance") where two particles interact then move apart with some indeterminate properties. When a property is measured on one particle a corresponding property is instantaneously changed on the other particle even though the particles may have moved a long way apart, ie, without any possibility of normal information exchange. A mooted explanation is for the "cause" to propagate backwards in time from the measured particle to the original interaction then forwards to the second particle. This contradict our intuitions of causes occurring before their effect but this may be ok since our idea of cause and effect is generated in our macro structure, based on the intuitions gained from in the macro world where time "flows", and only one way.
(comment at Mindblog)
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