Where Quantum Probability Comes From

[Binary_Bark]

In A Philosophical Essay on Probabilities, published in 1814, Pierre-Simon Laplace introduced a notorious hypothetical creature: a “vast intelligence” that knew the complete physical state of the present universe. For such an entity, dubbed “Laplace’s demon” by subsequent commentators, there would be no mystery about what had happened in the past or what would happen at any time in the future. According to the clockwork universe described by Isaac Newton, the past and future are exactly determined by the present.

Laplace’s demon was never supposed to be a practical thought experiment; the imagined intelligence would have to be essentially as vast as the universe itself. And in practice, chaotic dynamics can amplify tiny imperfections in the initial knowledge of the system into complete uncertainty later on. But in principle, Newtonian mechanics is deterministic.

More At: https://www.quantamagazine.org/where-quantum-probability-comes-from-20190909/

 

[My_King]

But then all variables need to be known of "present" to be able to predict exact future and exact past

 

[Ponderer]

"...the past and future are exactly determined by the present."

How can the "past" be determined by the "present"?
The "past" is the "past" - nothing can change the "past".

 

[FapCop]

How can the "past" be determined by the "present"?

"There are footprints in the sand at the present moment in time, therefore we determined that someone was walking here in a past moment"

Seriously, how hard is this?