• intensely_human@lemm.ee
    link
    fedilink
    arrow-up
    2
    ·
    7 months ago

    Analog signals can only be “perfectly” reproduced up to a specific target frequency. Given the actual signal is composed of infinite frequencies, you needs twice infinite sampling frequency to completely reproduce it.

    • Blue_Morpho@lemmy.world
      link
      fedilink
      arrow-up
      2
      ·
      7 months ago

      There aren’t infinite frequencies.

      “The mean free path in air is 68nm, and the mean inter-atomic spacing is some tens of nms about 30, while the speed of sound in air is 300 m/s, so that the absolute maximum frequency is about 5 Ghz.”

      • intensely_human@lemm.ee
        link
        fedilink
        arrow-up
        1
        ·
        6 months ago

        The term “mean free path” sounds a lot like an average to me, implying an distribution which extends beyond that number.

        • Blue_Morpho@lemmy.world
          link
          fedilink
          arrow-up
          1
          ·
          edit-2
          6 months ago

          One cubic centimeter of air contains 90,000,000,000,000 atoms. In that context, mean free path is 68nm up to the limits of your ability to measure. That is flip a coin 90 million million times and average the heads and tails. It’s going to be extremely close to 50%.

          Not to mention that at 5ghz, the sound can only propagate 68 nm.