On Thu, Mar 7, 2013 at 6:51 AM, Tim Tyler <[email protected]> wrote: > Power requirements for computation have dropped with minaturization. Today's > tablets don't usually risk melting your thighs, which equivalent computational > power would have done a few years back. There are limits (Landauer's > Principle) > to what you can do without reversibility - but these are still some way off. > > So: you really have to take decreasing power requirements into account when > extrapolating.
Over the last 40 years, power per square cm of silicon has remained pretty constant while the number of gates and bit operations per second doubled every 1.5 to 2 years. Current feature sizes are about 22 nm or 100 atoms. As features get smaller, power consumption drops. It is unlikely that silicon transistors could be shrunk below 2 nm, which is less than the average distance between the P-type or N-type dopant atoms. Assuming that we could, power consumption might drop by a factor of 100, which is still 4000 times higher than the human brain. Powering 10^10 such computers would require 1000 TW (vs. 18 TW we use now), and would raise the Earth's temperature by 0.5 C. I am confident that more efficient designs will be discovered, because we know they exist in nature. But right now the technology is not even in the research stage. -- -- Matt Mahoney, [email protected] ------------------------------------------- AGI Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/21088071-f452e424 Modify Your Subscription: https://www.listbox.com/member/?member_id=21088071&id_secret=21088071-58d57657 Powered by Listbox: http://www.listbox.com
