From Such Simple a Beginning: The Momentous Consequences of Physics' Microscopic Reversibility for Communication and Computation—and Almost Anything Else

Darwin concludes The Origin of Species with a splendid one-phrase poem,From so simple a beginningendless forms most beautiful and most wonderfulhave been, and are being, evolved.Full-size tableTable optionsView in workspaceDownload as CSV Darwin's “simple beginning” may be identified, in today's terminology, with dissipation—evolution's basic fuel. All the rest is commentary—or, more precisely, corollary.One can aptly apply Darwin's phrase to another kind of “simple beginning,” from which as well “endless forms most beautiful and most wonderful have been, and are being, evolved.” What I have in mind is a concept that is apparently the very antithesis of dissipation, namely, physics' fundamental assumption of invertibility—or “microscopic reversibility.” To paraphrase Dobzhansky, no sensible step can be taken today in information, communication, and computer sciences, as well as in fundamental physics, except in the light of invertibility.