> that's what consciousness is

How do you go from computation to feeling a toothache?

It's like telling me a cucumber is really a Porsche (but worse).

Who says neural networks aren't in pain when their fitness (reward function) is subtracted from? or happy or orgasmic when the function is bumped up?

Pain/pleasure seem to have easy enough analogue to at least something like a reward function, but what really gets me is colors. I feel like if honestly considered, the word "color" is all that's necessary to disprove materialism. Color is. How? Dunno.

Perceptions and feelings are real as you both experience them and could measure their signals in the brain, if you would have the proper tech to do that. And filtered, processed perceptions exist as well. In a "pipeline" in some brain - no matter if biological or artificial - somewhere in the middle you have processed signals of sensor input that have a complex meaning that has only some relation to the actual physical world "seen" by the sensors. Things like color and motion seem one of those; for an intuitive understanding it seems very close to the distill.pub analyses of what some specific middle-neurons in a convnet see.

> It's difficult to even imagine a physical theory with unbounded local information. It seems to open the possibility to crazy things like hypercomputation, which do not seem very well defined. (For example: every 1-1/n seconds, (n>1) from now, flip a switch ON/OFF. At what state will the switch be at t>1s? An at exactly t=1s?)

I agree with the latter, but the former? Classical Newtonian mechanics is easy enough to imagine.

What baffles me a bit is that quantum mechanics seems to be linear, but we seem to see chaos in the real world. (And exactly that (mathematical) chaos is also what the article exploits.)

Chaos arises in very simple (Newtonian) systems, e.g. the double pendulum[1].

1. https://en.m.wikipedia.org/wiki/Double_pendulum

Yes, Chaos arises in Newtonian systems just fine. They are non-linear. But Quantum Mechanics is linear.

See eg https://physics.stackexchange.com/questions/33344/is-the-uni... for a discussion, and https://www.scottaaronson.com/papers/island.pdf for a longer treatment.

QM being linear doesn't make the universe linear. Schrodinger's equation doesn't work across measurements (or universes.) And if you try to weasel out of that by saying we will describe the multiverse instead, you have just created the unexplainable phenomena of being in a specific universe, with no way to accurately describe the process behind the random choice of the universe you reside in.

> unexplainable phenomena of being in a specific universe

One universe has "observer" (a bunch of variables, really) in one state, another has it in different state. Those variables encode some information about themselves, so indeed in different universes the different "versions" of the observer are different, and each perceive it as universe randomly deciding to chose their version of existence. So what?

We're parts of the physical reality so trying to describing physics from the point of view of an out-of-universe observer, while psychologically attractive, is ultimately futile: in QM, such approach breaks very quickly.

Measurements (and 'universes') are part of interpretations of QM. Not sure they are properly part of QM. I see what you mean though.

I'm not sure whether eg the Born rule is enough by itself to explain how (non-linear) chaos arises from linear QM.

the issue isn't brains

no algorithm running on a cpu can move a muscle --

it is precisely that movement is a spatiotemporal property which means no turing machine can realise it

movement isn't a symbolic operation

What do you suppose those computers are doing, then? ;)

https://www.youtube.com/watch?v=tF4DML7FIWk

https://www.youtube.com/watch?v=tfb6aEUMC04&t=115s

I would go a step further and look at the research on medical devices for spinal-damage patients which try to literally control their existing muscles through a computer; the concept of neuroprosthesis and https://en.wikipedia.org/wiki/Functional_electrical_stimulat... working to design algorithms on CPU to move muscles, as the parent post words it.

In this very narrow sense that you are defining, no brain can move a muscle either. All it can do is send signals. A computer can do the same.

If you are making a broader claim about the limits of hardware vs. wetware the you will need to clarify things a bit further.

This is such a strange claim to make, I can't even tell what you could have meant. We are surrounded by simplistic mechanical computations moving muscles , and have been for more than a hundred years, since the industrial revolution at least.