• @[email protected]
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    01 year ago

    And a pool is clean for all intents and purposes. There is still a distinction though. The fact that it is deterministic inherently makes it less random than true randomness.

      • @[email protected]
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        01 year ago

        If you take the original values used to determine the final “random number” and run them through the same sequence of calculations, you will always reach the same value.

        We rely on the fact that the inputs are so numerous and/or difficult to replicate to deem the final value “random”. But that doesn’t mean that the value cannot be reached by a second party given perfect knowledge of the original state of all inputs.

        True randomness, on the other hand, is impossible to calculate even with that perfect knowledge, because we aren’t relying on the state of inputs running through a calculation.

        • @FooBarrington
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          1 year ago

          But that’s my point: just because you apply deterministic steps to a truly random input doesn’t make the output not truly random. You use real entropy as your starting point, which is literally exactly what you call “true randomness”. This means the output has the same level of “true randomness” as your “truly random” input, because you mathematically don’t lose entropy along the way.

          To put it more simply: you’re arguing from a philosophical perspective, not a mathematical one.

          • @[email protected]
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            01 year ago

            The input is not truly random though. If it was, we could just use that input, with no other steps, and have a truly random output. You’re confusing an unknown state with randomness.

            • @FooBarrington
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              21 year ago

              No, it actually and literally is truly random. You’d need to know everything about the hardware itself and the environment around it in incredible detail (incl. the temperature of every individual small patch of material, air flow and the state of air in and around the case) to reliably predict the initial entropy for a given modern system, since tiny changes in e.g. temperature will completely change the input.

              It’s only a small bit of entropy, but enough to kick-start the RNG in a way that can reliably create high-quality entropy.

              • @[email protected]
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                01 year ago

                So you’re literally arguing that knowable inputs, however unlikely knowing those inputs might be, run through known deterministic calculations, results in a guaranteed unknowable output?

                • @FooBarrington
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                  21 year ago

                  No, I’m arguing that the inputs aren’t knowable to the required degree in the general case, which defines their entropy, and that entropy isn’t mathematically lost, it’s improved through deterministic calculations.

                  • @[email protected]
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                    01 year ago

                    The same was thought about previous iterations on random number generators. The first I am aware of used an extremely precise time stamp, and ran the calculations on that. On the assumption that no one could possibly know the exact timestamp used. That was obviously untrue, which can be verified by the fact that such systems have been broken before.

                    Just because you can’t conceive of a way to know the values, does not make them unknowable. It just makes it improbable to happen.

                    And again, I’m not saying the random numbers we can produce now are currently breakable. But that doesn’t mean that a decade from now, or even a century, they will remain unbroken.