The graph at right (click to enlarge) shows computations/kilowatt-hour on the vertical axis (logarithmic), and time on the horizontal. When I got started in computing, one could do about 10 million (10^7) computations with a kilowatt-hour of power. Today one can do about 1 quadrillion (10^15) computations with that same power. In other words, one can do 100 million (10^8) times as many computations today for a given amount of power as could be done in 1970. 100 million!
This trend shows no signs of slowing down, much less stopping. Feynman's calculation of theoretical limits, so many years ago, says that we've just scratched the surface. The theory and the track record both lend credence to the trend continuing for a long time – and
that leads to some interesting things...
