I disagree with that post and its first two links so thoroughly that any direct reply or commentary on it would be more negative than I’d like to be on this site. (I do appreciate your comment, though, don’t take this as discouragement for clarifying your position.) I don’t want to leave it at that, so instead let me give a quick thought experiment.
A neuron’s signal hop latency is about 5ms, and in that time light can travel about 1500km, a distance approximately equal to the radius of the moon. You could build a machine literally the size of the moon, floating in deep space, before the speed of light between the neurons became a problem relative to the chemical signals in biology, as long as no single neuron went more than half way through. Unlike today’s silicon chips, a system like this would be restricted by the same latency propagation limits that the brain is, but still, it’s the size of the moon. You could hook this moon-sized computer to a human-shaped shell on Earth, and as long as the computer was directly overhead, the human body could be as responsive and fully updatable as a real human.
While such a computer is obviously impractical on so many levels, I find it a good frame of reference to think about the characteristics of how computers scale upwards, much like Feynman’s There’s Plenty of Room at the Bottom was a good frame of reference for scaling down, considered back when transistors were still wired by hand. In particular, the speed of light is not a problem, and will never become one, except where it’s a resource we use inefficiently.
I disagree with that post and its first two links so thoroughly that any direct reply or commentary on it would be more negative than I’d like to be on this site. (I do appreciate your comment, though, don’t take this as discouragement for clarifying your position.) I don’t want to leave it at that, so instead let me give a quick thought experiment.
A neuron’s signal hop latency is about 5ms, and in that time light can travel about 1500km, a distance approximately equal to the radius of the moon. You could build a machine literally the size of the moon, floating in deep space, before the speed of light between the neurons became a problem relative to the chemical signals in biology, as long as no single neuron went more than half way through. Unlike today’s silicon chips, a system like this would be restricted by the same latency propagation limits that the brain is, but still, it’s the size of the moon. You could hook this moon-sized computer to a human-shaped shell on Earth, and as long as the computer was directly overhead, the human body could be as responsive and fully updatable as a real human.
While such a computer is obviously impractical on so many levels, I find it a good frame of reference to think about the characteristics of how computers scale upwards, much like Feynman’s There’s Plenty of Room at the Bottom was a good frame of reference for scaling down, considered back when transistors were still wired by hand. In particular, the speed of light is not a problem, and will never become one, except where it’s a resource we use inefficiently.