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Simulating 1 second of real brain activity takes 40 minutes and 83K processors

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Re: Simulating 1 second of real brain activity takes 40 minutes and 83K processors

#61

Post by Volpe »

IvyMike wrote: post #3

At what point does this become unethical (if ever)? Before you answer, please consider how certain you are that you are not a simulation. Edit: I don't know the answer, and there probably is a large gray area. But I do know this starts to make me uncomfortable the more accurate it gets. Time to go reread Egan's Axiomatic again, I guess.

Given we are comfortable with firing bullets into each other. (i.e. killing what is already accepted as human life)

I find it difficult to see how this could ever be unethical (given the status quo).

Re: Simulating 1 second of real brain activity takes 40 minutes and 83K processors

#62

Post by oh_teh_meows »

anigbrowl wrote: post #32
oh_teh_meows wrote: post #25

Earlier quoted context omitted.

I'm not certain if that extrapolation you made of the time it takes to simulate a brain at the same abstraction level is valid. You're assuming the computation cycles needed will scale linearly, which might not be true considering that the brain is a network of neurons, where each neuron has a high number of in/out links to many other neurons. Consider the case where you take n seconds to simulate n neurons. Now add…

It's not my extrapolation, it's from the TFA, yes they assumed lineaar scaling.

Oh I see. Sorry. Should have read TFA closely :-/

Re: Simulating 1 second of real brain activity takes 40 minutes and 83K processors

#64

Post by smosher »

dekhn wrote: post #56
Xcelerate wrote: post #49

The title statement is almost meaningless. It would be better just to say "simulating reality takes a LONG time". My research is in molecular dynamics. I simulate systems up to 1 billion atoms on Kraken & Titan. HUGE approximations are made in simulating these systems, but depending on what exactly it is you're studying, these simulations still provide useful results. That is the key to all these studies: how well do…

Generally, the people doing brain simulations like to claim that they can use a massively reduced representation (little more than a graph model that pushes signals around with some constants) and yet, somehow, the simulation is inherently capable of reproducing something complex about thought. I'm not sure how they get to this conclusion, but it's a massive reductionism. It would be nice if it were true- it would me…

> something complex about thought

Can you elaborate on this class of 'something'? There are intelligent behaviours that can be reproduced this way, so without more specifics I feel like you're making the same mistake you're condemning.

Re: Simulating 1 second of real brain activity takes 40 minutes and 83K processors

#65

Post by moocowduckquack »

jfoutz wrote: post #45
moocowduckquack wrote: post #41

Earlier quoted context omitted.

"My understanding of "solution" is stuff floating in water." In that case, don't even bother with trying to work out what it would take to mathematically model biochemistry yet. Go study some basic physics and chemistry for a few years instead.

Ah yes, i called out water specifically and therefore i am an idiot. Mia Culpa. Best of luck with your simulation, i'm sure that individual atom model will work out great.

I don't know if you are an idiot, however you appear to have not even the slightest bit of technical understanding of the subject you are offering opinions on.

I am not attempting to be insulting, I am attempting to point out to you that you need to go and learn a hell of a lot more about the sciences than you seem to know at the moment if you are going to have any sort of productive discussion about the technical aspects of modelling biochemistry.

Re: Simulating 1 second of real brain activity takes 40 minutes and 83K processors

#66

Post by chongli »

jfoutz wrote: post #45
moocowduckquack wrote: post #41

Earlier quoted context omitted.

"My understanding of "solution" is stuff floating in water." In that case, don't even bother with trying to work out what it would take to mathematically model biochemistry yet. Go study some basic physics and chemistry for a few years instead.

Ah yes, i called out water specifically and therefore i am an idiot. Mia Culpa. Best of luck with your simulation, i'm sure that individual atom model will work out great.

Just to scratch the surface of how complex water is, I suggest taking a look at this wikipedia article:

http://en.wikipedia.org/wiki/Properties_of_water

Re: Simulating 1 second of real brain activity takes 40 minutes and 83K processors

#67

Post by jonmrodriguez »

smosher wrote: post #64
dekhn wrote: post #56

Earlier quoted context omitted.

Generally, the people doing brain simulations like to claim that they can use a massively reduced representation (little more than a graph model that pushes signals around with some constants) and yet, somehow, the simulation is inherently capable of reproducing something complex about thought. I'm not sure how they get to this conclusion, but it's a massive reductionism. It would be nice if it were true- it would me…

> something complex about thought Can you elaborate on this class of 'something'? There are intelligent behaviours that can be reproduced this way, so without more specifics I feel like you're making the same mistake you're condemning.

For example, the glial cells are now believed to be vital to the brain's processing, but most "brain simulations" are still modeling neurons only, not glia.

http://shahamlab.rockefeller.edu/pdf/CTDB_69_C_69003.pdf

Re: Simulating 1 second of real brain activity takes 40 minutes and 83K processors

#68

Post by dnautics »

gwern wrote: post #53
dnautics wrote: post #27

Earlier quoted context omitted.

I happen to work in the synthetic biology lab at the venter institute, although not on this project - two of our researchers are coauthors on this paper - and my personal opinion is that this paper is a joke. Note that the guys who made the simulation didn't even pick the correct organism. The cell that we have synthetic control over is M. mycoides, not M. genitalium. Lest this seem like a nit-pickey detail, until th…

What did your colleagues make of your criticism?

A common theme where I work is me making a vociferous criticism, being ignored, and the things I say coming true later. (this is not to say that all of the objections I make wind up being correct)

Re: Simulating 1 second of real brain activity takes 40 minutes and 83K processors

#69

Post by dnautics »

gwern wrote: post #52
Dylan16807 wrote: post #24

Earlier quoted context omitted.

Why does it show that the belief isn't accurate? This isn't simulating a brain, it's simulating the connections in a brain and pretending the neurons are about as complex as wires. That is a model that is possibly correct, but there's certainly no evidence it's correct.

It shows, at a minimum, that 'simulating' is not a binary either-or proposition, and that the higher-level a simulation, the easier/more efficient the simulation can be, and so it is perfectly possible to have a high-level simulation of a 'big' thing which is easier to run than a low-level simulation of a 'small' thing - both of these points, as obvious as they may seem to you or me, are badly underappreciated by a l…

then why is the modeling attempting to recapitulate biology? Why not run a simulation at a level higher than 'cells'?

Re: Simulating 1 second of real brain activity takes 40 minutes and 83K processors

#70

Post by moocowduckquack »

dnautics wrote: post #68
gwern wrote: post #53

Earlier quoted context omitted.

What did your colleagues make of your criticism?

A common theme where I work is me making a vociferous criticism, being ignored, and the things I say coming true later. (this is not to say that all of the objections I make wind up being correct)

You didn't refuse the advances of Apollo by any chance?
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