Accelerating Future

It seems that math may be unreasonably effective for understanding the universe. Complex phenomena, simple rules.

The universe may be simpler than it looks. It may in fact contain almost no information. Tegmark and other physicists argue that the universe is isomorphic to a mathematical structure and we are currently uncovering all the information content incrementally. In this view, our mathematics is a mathematical structure approximating another mathematical structure, rather than a mathematical structure approximating a physical structure.

So the universe could be a simple mathematical structure with self-similarity on all scales, like a fractal. In the abstract to an aforelinked paper, Tegmark writes, “In this paper, it is suggested that most of this information is merely apparent, as seen from our subjective viewpoints, and that the algorithmic information content of the universe as a whole is close to zero.” So the universe’s mathematical simplicity can be reconciled with its apparent complexity from our point of view.

Many physicsts believe all possible universes exist. According to the teleological-sounding but theoretically elegant anthropic principle, only those universes which permit conscious observers to exist are observable. If our universe is indeed quite simple, it surely cannot be too simple, otherwise it would lack conscious observers to experience it. It would make much more sense if it were as simple as possible but still complex enough to harbor consciousness.

I reached this idea on my own some time ago, and it seems that a few others have also discovered it independently. A search for “simplest possible universe” brings up a mailing list post by Fred Chen, a page on anthropics without an author indicated, and a book, Theory of Nothing, by Russell K. Standish, an associate professor with the math department at the University of New South Wales. German AI researcher Jürgen Schmidhuber also addresses the issue here.

Two begging questions seem to come out of this idea. The first is that there must exist some absolute criteria for the development of self-aware consciousness, and that these criteria have, self-evidently, been satisfied in this universe - but what are they? With a sample set of one, it’s hard to tell. The second question is, “is there an underlying mechanism with its own internal complexity that generates universes?” If all types of universe are realized an infinite number of times, then why is it any more likely for any given sentient being to be born into a simple universe?

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Humans find it hard to imagine intelligences smarter than we are because we’re designed by evolution to ignore the problems we can’t solve and focus on those we can. Doing it any other way would be an inappropriate use of cognitive resources.

What are the top five elements in your body and their relative proportions? You can’t answer? What’s taking you so long? You don’t even know what you’re made of?

Fact is, humans are pretty damn stupid. Not stupid relative to me or stupid relative to Einstein, but stupid in the scheme of things. Stupid relative to what we could be. We can offer any number of excuses, but in the end they’re nothing but excuses.

Homo sapiens evolved out of the primordial muck. We’re what happens when the muck gets just barely smart enough to reflect upon itself and manipulate its environment significantly.

There are two anthropic pressures at play here. Let’s assume, like Max Tegmark and other physicists, that we live in a gigantic multiverse where all possibilities are realized. The sector of the multiverse capable of harboring intelligent life, or life of any type, is extremely small. If our spatial dimensionality were different, or the intensity of the strong force, or the fine structure constant, or any number of other fundamental constants varied by even a tiny bit, life in this universe would be impossible. Tipler and Barrow beat this point into the ground in The Anthropic Cosmological Principle, but we’ve seen it already from numerous physicists.

The first anthropic pressure is the probabilistic bias towards chaos, disorder, and inhospitability to life, intelligent life in particular. In most of the multiverse life is impossible. But in some tiny portion, in which we (surprise!) happen to find ourselves, intelligent life just barely was able to evolve out of the muck and acquire enough cognitive complexity to consciously kill each other and compete for mates instead of just doing so mindlessly.

The second anthropic pressure is slightly more speculative. It’s the idea that intelligent species that are too smart wipe themselves out too quickly to really get anywhere. They build self-improving AIs that ignore their creators and tile the cosmic neighborhood with value structures that are a mere shadow of what the programmers originally meant, or launch superintelligent uploads who slowly, and then quickly become obsessed with the idea of constantly stimulating their own pleasure centers to the exclusion of all other pursuits. Both outcomes radically reduce the number of conscious individuals in existence after that point, thereby selecting those quadrants of spacetime out of the anthropic lottery. We’re unlikely to be born into those regions because they are relatively uninhabited, just like we’re unlikely to be born in universes where infant stars have so much gravity that their accretion discs get sucked in before forming stable planets.

We are born in regions that are typical. Industrial civilizations filled with billions of non self-modifying intelligent social animals, apparently. We’re relatively unintelligent because 1) we just evolved from the muck and 2) because we haven’t been clever enough to destroy ourselves yet. Two factors, any one of which alone would be enough to hold the argument up.

But, worry not. There is no reason to despair. These anthropic arguments for our relative stupidity only underscore our potential for growth. We can improve our quality of life to new heights we could never even dream of.

There is an issue of concern, however. If the future is so much more prosperous and populous than today, then why don’t we find ourselves there, instead of here? If out of every 1,000,000 random beings, only one finds itself in civilizations with only a few billion people, then is it just an enormous coincidence that we happen to find ourselves here?

Coincidence is not a satisfactory explanation. There are reasons to believe that this probabilistic issue is a huge problem. It’s called the Doomsday Argument. You can find numerous rebuttals in the Wikipedia article, but many of them are quite subtle, and if you dismiss the argument merely based on its implications, then I think we can justifiably throw out your opinion.

What is your reason for dismissing the Doomsday Argument? Or if you don’t have one, how do you cope?

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This posting is just for those who hadn’t yet seen it. Max Tegmark views our universe as one among many possible mathematical structures, and he believes that all mathematical stuctures are indeed manifested physically, though only a minority contain observers to testify to their existence. His Multiverse FAQ can be found here. Tegmark’s conclusions have big anthropic implications, the likes of which we’re only just beginning to unravel. He also wrote a paper on why anthropic considerations force all intelligent observers into universes with three space dimensions and one time dimension.

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