This month’s Futures story in Nature Physics is On the nature of reality by Yaroslav Barsukov. Here he explains the origins of his tale — as ever, it pays to read the story first.
Writing On the nature of reality
What is the most frightening thing? Many would say it’s death, the idea that a brain, an infinitely complex tangle of neural pathways, can dissolve into nothing. But I think the potential for horror is much greater if we look at our beginnings.
Superstring theory explains the observable phenomena by saying that there are really ten dimensions; in addition to the familiar ones of space and time, six extra dimensions exist that are ‘rolled up’ in a compact manifold. The configuration of this manifold determines the laws of physics.
However, once we say there are ten dimensions, for me the next question is: how so? Why ten and not six or nine? Obviously the answer that ‘otherwise the strings couldn’t vibrate in a consistent way’ is a circular argument; one is effectively saying our Universe exists in ten dimensions because that many are needed for our Universe to exist. The statement about the manifold is information in itself — and every information has to be defined somewhere, on some meta-level. Even if we step down from the complexity of string theory, there are multiple properties of reality that still require definition — causality itself being one example.
Somewhere it needs to be specified that our Universe exists in ten dimensions, and that there is causality and the flow of time.
You can’t infinitely stack meta-levels on top of each other (see the Homunculus argument). The only meta-level should be self-consistent; it wouldn’t need another, deeper layer to describe itself, and, mapped to our concepts, it would have no beginning and no end in time. And here we tread very close to the Bible … The alternative is more Lovecraftian to me than anything August Derleth — or Lovecraft himself — might have written. We could imagine that the meta-level doesn’t exist at all, which implies that the properties of the observable world aren’t defined anywhere, and thus the Universe came out of nothing.
Yet nothing will always produce nothing.
Obviously the boundaries of a flash piece are too constricting to tackle these concepts; you have to scale down. But I think the black cubes of the story can serve as a neat little metaphor for an ‘undefined’ reality. If a device similar to the one described existed, it would quite possibly invoke in people nothing but a sense of cosmic horror — and yet for many, a Universe without the meta-level is totally acceptable.
I don’t know why. And this frightens me, too.