Slashdot Mirror
Calculating A Theoretical Boundary To Computation
TMB writes "Lawrence Krauss and Glenn Starkman, astrophysicists at Case Western Reserve University (and in LK's case, author of a number of books including Physics of Star Trek), just submitted this nice little paper to Phys. Rev. Letters. It claims that in an accelerating universe, the existence of a future event horizon puts a fundamental physical limit on the total amount of calculation that can be done, even in an infinite time. This limit is much smaller than the traditional Hawking-Beckenstein entropy. Among other things, this implies that and Moore's Law must have a finite lifetime, here calculated to be 600 years, and that consciousness must be finite."
"consciousness must be finite"
;)
Except, of course, for those using certain popular mind-expanding substances
Seriously though - it seems we are finding a new limit every day. Wasn't it last week that they theorized limitations on data storage, as well as data transmission speed?
- To err is human; but to really screw up, you need a computer
Moore's law was never intended to be a scientific theory. It was just a useful observation. It has never had anything other than economic incentive to keep it going. Using it to discuss the calculational ability of the universe is idiotic.
Penrose is a mathematician who attempts to be philospohical and fails miserably, because he can't distinguish his intuition from fact. You don't need a link. Just remember that he wrote "The Emperor's New Mind", and coil away in horror.
Or looked at another way, proof that any "manifestation" of a supreme being in this universe must have finite wisdom, even if somehow (however nonsensical) a supreme being "outside" this universe might still have infinite wisdom. So in order to be known to mankind, you'd need to transmit a "finite" approximation of yourself -- hmmm...
I hope that after I die the one word people use to describe me is "resurrected."
Moore's Law is not a physical theory, it is the observation of a common phenomenon, namely the curve that technology goes through as it becomes cheaper and eventually free.
All technologies seem to obey this general law. Software, chips, disk space, they all tend to zero.
Even a passenger jet costs a fraction of what it did 20 years ago.
Moore's Law turns this around to say that for the same price we can expect more and more capacity. Long before 600 years are passed, this capacity will effectively reach "infinite", being the point where no-one can use more capacity or power, no matter what the application. At which point Moore's Law will gently slow down.
Ceci n'est pas une signature
This is great work.
If there's a limit to consiousness on the high end of an expanding universe then we should also be able to make educated guesses at the low end and then put a front time on the resulting "wave" of intelligence.
If we have a beggining of the "wave" then we should be able to make better educated guesses about the distribution of intelligence in the universe and possible level of advancement of any intelligent life we might find. We might discover, for example, that we're reletively advanced (came early in the wave) and that we're less likely to find more advanced life. On the other hand, we may find that we're late in the wave and thus likely surrounded by life much more advanced than us.
This could be a much better way of looking at extraterrestrial life than just guessing based on the number of stars.
TW
I haven't read SotM, so I can't comment on that. My biggest problem with Penrose is that I personally am convinced that strong AI can be achieved, while Penrose believes that it is impossible. That does not mean that the book can't be good, but Penrose doesn't do a good job matching his arguments with those of his opponents.
He has a tendency to repeat arguments that strong AI supporters give, but in a way that they can be misunderstood, and then he misunderstands them and basically says they are stupid. Already in chapter one of ENM he starts ridiculing strong-AI supporters, without giving arguments. Later those arguments follow, but they are seriously flawed.
For example, while discussing Searle's Chinese Room experiment, he suggests that strong-AI supporters believe that "understanding Chinese" is in the book, and argues that it is stupid that a book can "understand" anything. But Turing's view (which is repeated by many others) is that the understanding is not in the book, but in the book + the human that reads the book. There is an emergent understanding of Chinese that comes from a book that describes how Chinese can be perfectly translated, and a human who strictly follows the rules that are written down in the book. This argument is mentioned by Penrose somewhere, but he just puts it aside as a very weak argument, that does not need refuting.
Writing like this annoys me immensly, and I suspect most my colleague AI researchers.
Incidentally, I think Penrose' work in mathematics is absolutely brilliant.