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The Ultimate Limit of Moore's Law
BuzzSkyline writes "Physicists have found that there is an ultimate limit to the speed of calculations, regardless of any improvements in technology. According to the researchers who found the computation limit, the bound 'poses an absolute law of nature, just like the speed of light.' While many experts expect technological limits to kick in eventually, engineers always seem to find ways around such roadblocks. If the physicists are right, though, no technology could ever beat the ultimate limit they've calculated — which is about 10^16 times faster than today's fastest machines. At the current Moore's Law pace, computational speeds will hit the wall in 75 to 80 years. A paper describing the analysis, which relies on thermodynamics, quantum mechanics, and information theory, appeared in a recent issue of Physical Review Letters (abstract here)."
Intel co-founder Gordon Moore predicted 40 years ago that manufacturers could double computing speed every two years or so
by cramming ever-tinier transistors on a chip.
That's not exactly correct. Moore's Law (or observation more like) reads in the original article as:
The complexity for minimum component costs has increased at a rate of roughly a factor of two per year ... Certainly over the short term this rate can be expected to continue, if not to increase. Over the longer term, the rate of increase is a bit more uncertain, although there is no reason to believe it will not remain nearly constant for at least 10 years. That means by 1975, the number of components per integrated circuit for minimum cost will be 65,000. I believe that such a large circuit can be built on a single wafer.
All he's concerned about is quoting how many components can fit on a single integrated circuit. One can see this propagated to processing speed, memory capacity, sensors and even the number and size of pixels in digital cameras but his observation itself is about the size of transistors -- not speed.
The title should be "The Ultimate Limit of Computing Speed" not Moore's Law.
Furthermore, we've always had Planck Time as a lower bound on the time of one operation with our smallest measurement of time so far being 10^26 Planck Times. So essentially they've bumped that lower bound up and it's highly likely more discoveries will bump that even further up. I guess our kids and grandchildren have their work cut out for them.
My work here is dung.
From Wikipedia: "a computer the size of the entire Earth, operating at the Bremermann's limit could perform approximately 10^75 mathematical computations per second. If we assume that a cryptographic key can be tested with only one operation, then a typical 128 bit key could be cracked in 10^37 seconds. However, a 256 bit key (which is already in use in some systems) would take about a minute to crack. Using a 512 bit key would increase the cracking time to 10^71 years, but only halve the speed of encryption."
You see - the system that threatens to reduce your lifespan is a much faster way to acquire that key.
looks like we've almost reached that point now. We've had Xeon 3.0GHz cpus for over 5 years now, and they're still coming out with brand new 3ghz processors. That's a long time to not see a jump in speed, what happened to "doubling every 18 months"? We should be around 24ghz by now.
Sorry, Performance != Clockspeed
I, for one, am glad Intel went away from modeling their processors after their clockspeed. They went to an actual model for this reason. If you want an example where they didn't, and lower clock speed processors kept up just go back and look at the 423/427 Pentium 4's vs the Socket A Athlons (XP, ect)
Nitpick: that's 10^(-37) seconds, or ~2M Planck times.