Random Reality

Author and astronomer Marcus Chown on the early history of the universe, quantum reality, and the origins of information.

In Song of Myself, Walt Whitman wrote: “Let your soul stand cool and composed before a million universes.” Of course, he never meant it literally; he was using poetic license. But, remarkably, today, we know it is actually possible to stand cool and composed before a million universes. In my hand I am holding a 1-gigabit flash memory drive. You will have to trust me about that! A moment ago I fished it from my pocket and now it dangles on my key-ring. Believe it or not, it has the capacity to store the information for 1 million universes.

I too was pretty incredulous to discover this. But, before I explain, I should say that one consequence of all this is that Einstein was wrong when he declared: “God does not play dice with the universe.”  In other words, atoms did not do things unpredictably—completely at random—as the widely accepted theory of the microscopic world maintained. In fact, Einstein could not have been more completely, utterly, spectacularly wrong. And it is not often you can say that about the great man.

Enough of these teasers. Some essential background. The universe is currently expanding. Its basic building blocks—galaxies like our own Milky Way—are flying apart from each other like pieces of cosmic shrapnel in the aftermath of the big bang explosion from 13.7 billion years ago. Imagine, if you can, this expansion running backwards like a movie in reverse. Of course, the universe gets smaller and smaller.

However, it turns out that, as the universe gets smaller, there is less and less room for all the stuff within it. This is because we live in a fundamentally grainy universe. Ultimately, everything comes in tiny, indivisible chunks, or “quanta.” Matter comes in quanta, energy comes in quanta, time comes in quanta—and so does space. Imagine the space of the universe, then, as a giant chessboard, with the spaces as locations for putting stuff like matter or energy. Because the squares cannot get any smaller, in the past, when the universe was tinier, there were less of them.

Here we come to the crux of the matter. The universe is believed to have begun in epoch of super-fast expansion called “inflation.” And, prior to that, according to calculations by Stephen Hsu of the University of Oregon in Eugene, there were a mere 1000 locations—1000 chessboard squares, if you like—for stuff. Each of those 1000 locations could either contain energy or no energy. Describing its exact state would take just 1000 binary digits, or “bits,” of information. A gigabit flash memory drive, like the one on my key-ring, can store 1000 million bits. Hence, if Hsu is right, my key-ring drive can store the information describing the initial state of 1 million universes.

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