X-Message-Number: 11676 Date: Wed, 05 May 1999 10:35:11 +0000 From: Damien Broderick <> Subject: billions and trillions I wildly proposed: < if one had a sequential linear machine able to operate billions or trillions of times faster than a human brain > Thomas Donaldson commented: < I will point out that there are physical limits to just how fast a sequential computer can work (limits for quantum computation or parallel computation will clearly be different, though they also exist). > Here's a fragment morphed from the EETimes news (pictures at 11): =========== Researchers at Notre Dame university have demonstrated transistorless logic gates using quantum dots. Demonstrated designs include AND, NOR, and OR gates each (apparently) using four quantum dots, occupying five nanometers square. (It's not clear if the dots or the gates are each occupying 5 nm square.) Projected gate densities range up to 1 trillion (yes, 1e12) gates per square centimeter. Note also that the power density product for these devices is approximately one billionth that of transitor logic, and the power dissipated is expected to be the limiting factor in production. ========== Terafying, eh? Damien Broderick Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=11676