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0 pointsgeorgewsinger8y ago0 comments

Usually in math we assume the axiom of choice :) https://en.wikipedia.org/wiki/Axiom_of_choice I'm assuming this could somehow lead to such a "random" pick in the technical sense.

In terms of implementation, I'm not aware of an algorithm that can randomly pick a real number on an actual computer. Perhaps a mathematician could show how to pick one on some abstract machine with infinite resources, and not constrained by finite bit representations of numbers.

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dragonwriter8y ago

> In terms of implementation, I'm not aware of an algorithm that can randomly pick a real number on an actual computer

An actual (finite in time and space) computer can't even represent arbitrary real numbers, much less randomly choose them.

SomeStupidPoint8y ago

A Turing machine can't pick random numbers of any kind.

Once you accept that you have an entropy source in the physical world, you can easily be injecting random real numbers (from some range) and in fact, usually are, which are then being binned into integers by ADCs.

dorgo8y ago

What about PI? We can represent it in terms of "we know what we are talking about" and we can distinguish it from other numbers.

leni5368y ago

You can only have countable number of first or second order logic statements each defining a specific real number.

ouid8y ago

Those things sound equivalent, but I don't want to be the one to try to prove it.

red75prime8y ago

Run a random number generator (0-9) for each decimal position after the dot in parallel. This should do a trick.

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