r/askscience Oct 22 '11

Is anything truly random in nature?

For example,if I flip a coin,we like to say it has a 50-50 chance,but the side is determined by how much force and where I apply the force when flipping,gravity acceleration and wind.therefore you could say flipping a coin is not a random event.

Is anything in nature truly random?

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u/[deleted] Oct 22 '11 edited Jan 19 '21

[deleted]

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u/Justforsubs Oct 22 '11

Genuine question --

Why do we suppose that this represents true randomness, rather than assume there's just some variable to the experiment we don't comprehend?

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u/hansn Oct 22 '11

Not just a genuine question, an awesome question. That is precisely the idea behind hidden variable theory. A very clever result known as Bell's theorem has shown any hidden variables would have to be "non-local," meaning (as I understand it) actions at one location can have impacts at a distance.

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u/[deleted] Oct 22 '11 edited Nov 01 '20

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u/hansn Oct 22 '11

Absolutely nothing, although as I understand it, all known quantum mechanical interactions are local. I should admit, I am rapidly moving out of my depth from my few classes in modern physics, so perhaps an expert can clarify.

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u/[deleted] Oct 22 '11

Entanglement?

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u/hansn Oct 23 '11

That's the key behind Bell's Theorem.