Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

The Brain is Not Computable

technologyreview.com

Post reply on HN
Print view View original

41–50 of 76 posts

Re: The Brain is Not Computable

#41

Post by jpwagner »

guylhem wrote: post #3

Not with our current technology, I agree But saying the problem can't be solved ever seems dead wrong to me. We humans excel at understanding and replicating what nature did - then at improving it. Once we clearly understand how memories are stored, if they can be read and written that'll be half of the problem : accessing the data. If the theory about memory being encoded in the microtubules is right, imagine some n…

"We humans excel at understanding and replicating what nature did - then at improving it."

Do we?

Re: The Brain is Not Computable

#42

Post by bmh100 »

tibbon wrote: post #11

My girlfriend is a neuroscientist. Every time she sees something about them 'modeling the brain' she is visibly amused/unhappy. It might be possible, but our current understanding of the brain feels much further away. The concept that we're going to hit some moore's law style thing in science that will propel us to just automatically understand things, which we can barely measure currently, just doesn't line up. Just…

On the other hand, I believe we did see exponential growth in our ability to both automatically drive cars, to automatically translate text, and in voice recognition.

If we consider 1958 to be a good starting point for self-driving cars (http://technologizer.com/2010/10/09/google-self-driving-cars...), might we say that Google's car is orders of magnitude more powerful than those of 1986?

If we consider 1954 a starting point for machine translation (https://en.wikipedia.org/wiki/History_of_machine_translation), again might we find that Google Translate is similarly in a different league than SYSTRAN of the 1980s?

I do not really have the knowledge and sources to back those claims up, so I have to frame them as opinions for now. Could someone with experiences or deeper knowledge about these areas weigh in?

Re: The Brain is Not Computable

#43

Post by aaron695 »

LOL what total bunk, "unless" of course you practice some sort of magic and believe by definition humans cannot replicate this form of magic, then his theory might fit.

Besides which the Singularity has nothing to do with the 'soul' and consciousness. It's about super intelligence, this is possible without being self aware. IE Deep Blue I assume is not considered 'conscious' but it can solve the chess problem better than us, why would you think a super intelligent machine that can solve general problems has to also be 'self aware', bizarre.

Re: The Brain is Not Computable

#44

Post by [deleted] »

tibbon wrote: post #39
Aqueous wrote: post #21

Earlier quoted context omitted.

Right, it takes forever now - and it took twice as long five years ago.

But the thing is most neuroscientists don't just sit at a computer all day. 95% of the tasks they do are not computer-bound. If you're doing animal-based research (the majority of real neuroscience currently), then its time spent with behavior testing, surgeries, waiting for the drug to be in an animal for 72 (or however many) hours, processing slides, pipetting, etc. The time spent at a computer is mostly data analy…

[deleted]

Re: The Brain is Not Computable

#45

Post by MaysonL »

Aqueous wrote: post #33
defen wrote: post #23

Earlier quoted context omitted.

The problem with chaotic systems isn't simulating them, it's measuring the initial conditions. Arbitrarily small differences blow up exponentially fast even if your simulation has really, really small time steps.

The differences in initial conditions do cause the trajectories to diverge, but in certain systems they don't just diverge, they also get pulled into the orbit of an attractor, such as the Lorenz attractor. So, the behavior overall, despite being seemingly chaotic, is actually predictable and ordered.

Assumning there aren't multiple competing attractors.

Re: The Brain is Not Computable

#46

Post by defen »

VMG wrote: post #26
mistercow wrote: post #10

>That’s because its most important features are the result of unpredictable, non-linear interactions amongst billions of cells, Nicolelis says. Replace "cells" with "molecules" and "consciousness" with "fluid dynamics", and you can see what a vague, hand-waving argument this is. >“You can’t predict whether the stock market will go up or down because you can’t compute it,” he says. “You could have all the computer chi…

This quote also stumped me >“You can’t predict whether the stock market will go up or down because you can’t compute it,” If you had an accurate model of the agents, you could easily compute the stock market.

But as soon as you want to use that knowledge to actually make money, your agent is participating in the market, so it has to account for itself...

Re: The Brain is Not Computable

#47

Post by defen »

Aqueous wrote: post #33
defen wrote: post #23

Earlier quoted context omitted.

The problem with chaotic systems isn't simulating them, it's measuring the initial conditions. Arbitrarily small differences blow up exponentially fast even if your simulation has really, really small time steps.

The differences in initial conditions do cause the trajectories to diverge, but in certain systems they don't just diverge, they also get pulled into the orbit of an attractor, such as the Lorenz attractor. So, the behavior overall, despite being seemingly chaotic, is actually predictable and ordered.

To what extent is that actually useful if I want to know the specific state of the system at some point in the future, though? Even if I know the attractor I still can't measure the current state accurately enough to simulate its future state.

Re: The Brain is Not Computable

#48

Post by kristofferR »

stefantalpalaru wrote: post #9
coopdog wrote: post #2

Surely if you created a physics virtual machine and loaded an image with all of the atoms and electrons in place.. you'd simulate the brain. I imagine it would take a lot of computational power, but it's not 'never' Unless we're talking about souls here or something

If we really need to simulate interactions at molecular level we're fracked. That kind of computational power is unimaginable.

So was Petabytes 60 years ago, yet today there are people who have single-handedly uploaded more than that on private BitTorrent trackers.

Never say never.

Re: The Brain is Not Computable

#49

Post by JoeAltmaier »

kristofferR wrote: post #40

I simply can't understand why people feel the need to proclaim that something plausible will never ever happen some time in the (possibly very distant) future. It's both stupid, unproductive and often embarrassing (when they are proven wrong). >"But Nicolelis is in a camp that thinks that human consciousness (and if you believe in it, the soul) simply can’t be replicated in silicon. I'm guessing/hoping that the silic…

Agreed. The brain was 'invented' by non-intelligent evolution, a blind drunkard's walk of chemistry and biology. I am amazed we haven't figured out what mind-bogglingly simple premises are required to build a brain - it happened through a series of alway-stable always-useful small steps. I've seen a car designed by a web page through random 'genetic algorithm'. How about a simple random walk through neuron interconnection until something useful pops out?

Re: The Brain is Not Computable

#50

Post by pradocchia »

rm999 wrote: post #6

>But Nicolelis is in a camp that thinks that human consciousness (and if you believe in it, the soul) simply can’t be replicated in silicon. That’s because its most important features are the result of unpredictable, non-linear interactions amongst billions of cells, Nicolelis says. This is a fringe opinion, and I really wish the title reflected that. Ignoring the absurd 'linear' part of the article, I don't believe…

While it's possible quantum effects could explain unpredictability in the physical universe, there is no scientific evidence this is relevant to the brain; the brain operates at a much higher, more macro level than quantum mechanics.

The brain evolved in the physical world. It seems an odd economy to categorically exclude quantum effects because they are "too small", hard to measure, and/or poorly understood.

Post reply on HN