Moore’s law is ending for a wide variety of reasons including economic and physical, but worse still if we keep building processors as we traditionally do (this is called the Von Neumann architecture) we’re going to keep consuming more power.
A Way Around the Coming Performance Walls: Neuromorphic Hardware with Spiking Neurons
Sean Aubin
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For a more humourus account of his problem I highly recommend recommend this essay by James Mickens http://boingboing.net/2013/09/27/gonzo-essay-on-the-limits-of-c.html