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Comment author: GenericThinker 05 December 2008 09:28:36PM 3 points [-]

"If anyone from Intel reads this, and wishes to explain to me how it would be unbelievably difficult to do their jobs using computers from ten years earlier, so that Moore's Law would slow to a crawl - then I stand ready to be corrected. But relative to my present state of partial knowledge, I would say that this does not look like a strong feedback loop, compared to what happens to a compound interest investor when we bound their coupon income at 1998 levels for a while."

This is simple to disprove whether being part of intel or not. The issue is that since current processors with multiple cores and millions-now billions of transistors are getting so complex that the actual design has to be done on computer. What is more before fabrication the design needs to be simulate to check for logic errors and to ensure good performance. It would be impossible to simulate a Tera-scale research chip on 1998 hardware. The issue is that simulating a computers design require a lot of computational power. The advances made in going from 65nm to 45nm now moving to 32nm were enabled by computers that could better simulate the designs without todays computers it would be hard to design the fabrication systems or run the fabrication system for the future processors. Since you admit partial knowledge I won't bore you with the details of all this, suffices to say that your claim as state is incorrect.

I would however like to point out a misconception about Moores law, the law never says speed increases merely the number of transistors double every 18 months. There are a lot of facts apart from the number of transistors that play into computer speed. While more transistors are useful one has to match them with an architecture to take advantage of them otherwise you would not get the speed increase necessarily.

In response to Hard Takeoff
Comment author: GenericThinker 03 December 2008 03:17:29AM -1 points [-]

"But the much-vaunted "massive parallelism" of the human brain, is, I suspect, mostly cache lookups to make up for the sheer awkwardness of the brain's serial slowness - if your computer ran at 200Hz, you'd have to resort to all sorts of absurdly massive parallelism to get anything done in realtime. I suspect that, if correctly designed, a midsize computer cluster would be able to get high-grade thinking done at a serial speed much faster than human, even if the total parallel computing power was less."

That is just patently false, the brain is massively parallel and the parallelism is not cache look-ups it would be more like current GPUs. The computational estimate does not take into account for why the brain has as much computational power as it does ~10^15 or more. When you talk about relative speed what you have to remember is that we are tied to our perception of time which is roughly between 30-60FPS. Having speeds beyond 200Hz isn't necessary since the brain doesn't have RAM or caches like a traditional computer to store solutions in advance in the same way. By having the speed at 200Hz the brain can run fast enough to give us real-time perceptions while having time to do multi-step operations. A nice thing would be if we could think about multiple things in parallel the way a computer with multiple processors can focus on more then one application at the same time.

I think all these discussions of the brains speed are fundamentally misguided, and show lack of understanding of current neuroscience computational or otherwise. Since to say run the brain at 2Ghz what would that mean? How would that work with our sensory systems? If you only have one processing element with only 6-12 functional units then 2Ghz is nice if you have billions of little processors and your senses all run around 30-60FPS then 200Hz is just fine without being overkill unless your algorithms require more then 100 serial steps. My guess would be that brain does a form of parallel algorithms to process information to limit that possibility.

On the issue of mental processing power look at savants, some of them can count in primes all day long or can recite a million digits of pi. For some reason the disfunction in their brains allows them to tap into all sorts of computational power. The big issue with the brain is that we cannot focus on multiple things and the way in which we perform for example math is not nearly as streamlined as a computer. For may own part I am at my limit multiplying a 3 digit number by a 3 digit number in my head. This is of course a function of many things but it is in part a function of the limitations of short term memory and the way in which our brains allow us to do math.

Comment author: GenericThinker 02 December 2008 07:59:22PM 0 points [-]

"The explosion in computing capability is a historical phenomenon that has been going on for decades. For "specific numbers", for example, look at the well-documented growth of the computer industry since the 1950s. Yes, there are probably limits, but they seem far away - so far away, we are not even sure where they are, or even whether they exist."

The growth you are referring to has a hard upper limit which is when transistors are measured in angstroms, at the point when they start playing by the rules of quantum mechanics. That is the hard upper limit of computing that you are referring to. Now if we take quantum computing that may or may not take us further there has been a lot of work done recently that casts doubt on quantum computing and its ability to solve a lot of our computing issues. There are a lot of other possible computing technologies it is just not clear which one will emerge at the top yet.

Comment author: GenericThinker 27 November 2008 02:42:47PM -1 points [-]


"Also do you have some FLOPS per cubic centimeter estimations for nanocomputers? I looked at this briefly, and I couldn't find anything. It references a previous page that I can't find."

FLOPs are not a good measure of computing performance since Floating Point Calculations are only one small aspect of what computers have to do. Further the term nanocomputers as used is misleading since all of todays processors could be classified as nanocomputers the current ones using the 45nm process moving to the 32nm process.


"Just to make it clear why we might worry about this for nanotech, rather than say car manufacturing - if you can build things from atoms, then the environment contains an unlimited supply of perfectly machined spare parts. If your moleculary factory can build solar cells, it can acquire energy as well."

Ignoring the other obvious issues in your post, this is of course not true. One cannot just bond any atom to any atom this is well known and have something useful. I would also like to point out that everyone tosses around the term nano including the Foresight institute but the label has been so abused through projects that don't deserve it that it seems a bit meaningless.

The other issue is of course this concept that we will build everything from atoms in the future that you seem to imply. This is of course silly since building a 747 from atoms up is much harder then just doing it the way we do it now. Nano engineering has to be applied to the right aspects to make it useful.

"I don't think they've improved our own thinking processes even so much as the Scientific Revolution - yet. But some of the ways that computers are used to improve computers, verge on being repeatable (cyclic)."

This is not true either, current computers are designed by the previous generation. If we look at how things are done on the current processors and how they were done we see large improvements. The computing industry has made huge leaps forward since the early days.

Finally I have trouble with the assumption that once we have advanced nanotech whatever that means that we will all of a sudden have access to tremendously more computing power. Nanotech as such will not do this, regardless of whether we ever have molecular manufacturing we will have 16nm processors in a few years. Computing power should continue to follow Moore's law till processor components are measured in angstroms. This being the case the computer power to run the average estimates of the human brains computational power already exist. The IBM Roadrunner system is one example. The current issue is the software there is no end to possible hardware improvement but unless software matches who cares.

Comment author: GenericThinker 27 November 2008 04:38:57AM -1 points [-]

"For the record, I've been a coder and judged myself a reasonable hacker - set out to design my own programming language at one point, which I say not as a mark of virtue but just to demonstrate that I was in the game. (Gave it up when I realized AI wasn't about programming languages.)"

AI is about programming languages since AI is about computers, and current "AI" languages really aren't that great. I would say that it would be of huge value if someone could design an AI specific language that would be better then Lisp. Also a programming language that better deals with mass parallelism would be of great value to AI. Devoting yourself to that goal would further AI since the problem is one of theory and one of enabling technology.

Just an aside the good hacker in your own view isn't a good metric due to the fact that people always think of themselves as being better at something then they really are.

Comment author: GenericThinker 26 November 2008 09:15:20PM -2 points [-]

PK you are absolutely right. We can even take things a step further and say positive AI will happen regardless of Eliezer's involvement, and even as far as to say his involvement not having the needed experience in both math and programming will be as a cheerleader and not someone who makes it happen.

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