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Comment by Tomte

2 days ago

Starts interesting, then veers into the usual "true random number" bullshit. Use radioactive decay as source of your random numbers!

> Use radioactive decay

It's a lot easier to use diodes (light emitting and otherwise).

How do we know it's truly random?

  • The only known explanation of what's going on in quantum mechanics is a multiversal one^[1]. Using radioactive decay of an atom as an example: there are an uncountably infinite number of universes that are initially "fungible" (identical in every way), and over time the universes gradually differentiate themselves with the atom going from a non-decayed to decayed state, at different times in each universe. But you will be in all of those universes. So if you thought the atom would decay in, let's say 5 seconds, there would be some universes where you were right and some where you were wrong. That makes it impossible to ever make reliable specific predictions about when the atom will decay. So, in practice that just looks like perfect randomness.

    ^[1]: There are other interpretations, of course. And those other interpretations are equally explanatory. But they do not claim to be explanations of what is actually happening to unobserved quantum particles. There is also Bohmian mechanics, but I don't know how many people take it seriously.

  • We don't. We know with great certainty it's either random or needs non-local variables, which would let information travel faster than c, among other things. (This is a consistent result of the Bell test.)

    Most prefer to believe in randomness.

> usual "true random number" bullshit

What's bullshit about it? This is how TRNGs in security enclaves work. They collect entropy from the environment, and use that to continuously reseed a PRNG, which generates bits.

If you're talking "true" in the philosophical sense, that doesn't exist -- the whole concept of randomness relies on an oracle.

  • I don't think hardware random number generators are bullshit, but it's easy to overstate their importance. Outside of cryptography, there aren't a whole lot of cases that truly require that much care in how random numbers are generated. For the kind of examples the article opens with (web page A/B testing, clinical trials, etc.) you'll never have sample sizes large enough to justify worrying about the difference between a half-decent PRNG and a "true" random number generator.

    • Yes, agreed. In many cases, the determinism is a feature, particularly being able to store the seed for reproducibility.