• @FooBarrington@lemmy.world
    link
    fedilink
    31 year ago

    But it is truly random for all intents and purposes, since the input is truly random. Just because the process contains deterministic steps doesn’t mean the input entropy isn’t true entropy anymore.

    • @KairuByte@lemmy.dbzer0.com
      link
      fedilink
      11 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.

        • @KairuByte@lemmy.dbzer0.com
          link
          fedilink
          11 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@lemmy.world
            link
            fedilink
            3
            edit-2
            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.

            • @KairuByte@lemmy.dbzer0.com
              link
              fedilink
              11 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@lemmy.world
                link
                fedilink
                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.

                • @KairuByte@lemmy.dbzer0.com
                  link
                  fedilink
                  11 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@lemmy.world
                    link
                    fedilink
                    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.