March 7, 2011 | 54
Is everything information? This seductive idea animates the brand-new book The Information by James Gleick (Pantheon 2011), which I just rave-reviewed in The Wall Street Journal. Gleick’s book is, among other things, an in-depth biography of information theory, which the Bell Labs mathematician Claude Shannon invented in 1948 to provide a framework for improving the efficiency of communications.
A growing number of scientists, Gleick writes, are beginning to wonder whether information "may be primary: more fundamental than matter itself." This notion has inspired other recent books, including Programming the Universe by Seth Lloyd (Vintage 2007), Decoding the Universe by Charles Seife (Penguin 2007), Decoding Reality by Vlatko Vedral (Oxford 2010) and Information and the Nature of Reality, a collection of essays edited by Paul Davies (Cambridge 2010). But the everything-is-information meme violates common sense.
Reaching this conclusion wasn’t easy for me, because the meme was conceived by one of my all-time favorite scientists, the physicist-poet John Wheeler, who died three years ago. In the 1980s, Wheeler started pointing out deep resonances between quantum mechanics and information theory. An electron, Wheeler pointed out, behaves like a particle or a wave depending on how we interrogate it. Information theory, similarly, posits that all messages can be reduced to a sequence of "binary units," or bits, which are answers to yes or no questions.
Wheeler proposed that physics be recast in terms of information theory, an idea that he summarized in a koan-like phrase: "the it from bit." In a paper that he delivered at the Santa Fe Institute in 1989, he postulated that "every it–every particle, every field of force, even the spacetime continuum itself–derives its function, its meaning, its very existence entirely–even if in some contexts indirectly–from the apparatus-elicited answers to yes-or-no questions, binary choices, bits."
Wheeler once explained this concept to me by comparing a scientist to someone playing the "surprise version" of the old game 20 Questions. In this variant, the Guesser leaves the room while the rest of the group–or so the excluded person thinks–agrees on some person, place or thing. The Guesser then re-enters the room and tries to guess the group’s secret with a series of questions that can only be answered with a yes or a no.
But the group has decided to play a trick on the Guesser. The first person to be queried will only think of something after the Guesser asks his question. Each subsequent person will do the same, making sure that his or her response is consistent with all previous questions. "The word wasn’t in the room when I came in even though I thought it was," Wheeler noted. In the same way, physical reality exists in an indeterminate limbo before we pose our questions. "Not until you start asking a question, do you get something." We live in a "participatory universe," Wheeler suggested, which emerges from the interplay of consciousness and physical reality, the subjective and objective realms.
So what’s the problem with saying that everything comes down to information, bits, answers to our queries? First of all, as the physicist Rolf Landauer liked to say, all information is physical—that is, all information is embodied in physical things or processes—but that doesn’t mean that all things physical are reducible to information. The concept of information makes no sense in the absence of something to be informed—that is, a conscious observer capable of choice, or free will (sorry, I can’t help it, free will is an obsession). If all the humans in the world vanished tomorrow, all the information would vanish, too. Lacking minds to surprise and change, books and televisions and computers would be as dumb as stumps and stones. This fact may seem crushingly obvious, but it seems to be overlooked by many information enthusiasts.
The idea that mind is as fundamental as matter—which Wheeler’s "participatory universe" notion implies–also flies in the face of everyday experience. Matter can clearly exist without mind, but where do we see mind existing without matter? Shoot a man through the heart, and his mind vanishes while his matter persists. As far as we know, information—embodied in things like poetry, hiphop music and cell-phone images from Libya–only exists here on Earth and nowhere else in the universe. Did the big bang bang if there was no one there to hear it? Well, here we are, so I guess it did (and saying that God was listening is cheating).
Part of me would love to believe that consciousness is not an accidental by-product of the physical realm but is in some sense the primary purpose of reality. Without us to ponder it, the universe makes no sense; worse, it’s boring. But the hard-headed part of me sees ideas like the "it from bit" as the kind of fuzzy-headed, narcissistic mysticism that science is supposed to help us overcome.
Image courtesy of Wiki Commons.