Cosmic Natural Selection
If you regularly read this blog, you already know that I believe adaptive evolutionary processes explain system order in the universe. There does appear to be a unity between how systems evolve (whether they be chemical, biological, cultural, technological, etc.). In this sense, selection-like processes generate order in the natural world that many cultural groups assumed was intelligently designed. But can selection be extended to explain the universe itself?
Before humans knew that there were other planets in the universe, many people believed that Earth could only be explained by intelligent design (e.g., God). However, we now know that the Earth’s existence can be explained by probability. There are likely way more than sextillion planets in the observable universe, so it is not necessarily surprising that one suitable for complex life exists. In fact, it would not be surprising if billions of planets suitable for complex life existed just within our own galaxy.
But people who make the God-of-the-gaps argument never really go away. Now that it is intellectually bankrupt to argue Earth (or life, or our star, or our solar system, or our galaxy) was intelligently designed, many turn to the universe itself. As physicists have pointed out, our universe is well-designed for the emergence of intelligent life (although not that well-designed).
Therefore, it is the job of 21st century science to uncover the mysteries as to why our universe appears to have the physical constants it does. At the moment, the theory is far ahead of the empirical evidence (unlike the situation in evolutionary biology). A dominant theory proposed to explain our universe’s physical constants is [Cosmic Natural Selection](http://evodevouniverse.com/wiki/Cosmological_natural_selection_(fecund_universes) (CNS). This theory, first explored by physicist Lee Smolin suggests that:
black holes may be mechanisms of universe reproduction within the multiverse, an extended cosmological environment in which universes grow, die, and reproduce. Rather than a “dead” singularity at the centre of blackholes, a point where energy and space go to extremely high densities, what occurs in Smolin’s theory is a “bounce” that produces a new universe with parameters stochastically different from the parent universe. Smolin theorizes that these descendant universes will be likely to have similar fundamental physical parameters to the parent universe (such as the fine structure constant, the proton to electron mass ratio, and others) but that these parameters, and perhaps to some degree the laws that derive from them, will be slightly altered in some stochastic fashion during the replication process. Each universe therefore potentially gives rise to as many new universes as it has black holes.
The analogy with how selection operates in biological systems is impossible to miss. Given that this is how complexity is generated by other natural systems, it seems logical that this could be the case of our universe (within the multiverse). In fact, a study published this month in the journal Complexity posits that Smolin’s CNS theory would mathematically be in concordance with the production of universe’s increasingly likely to produce black holes (and therefore universe’s conducive to complex life).
Let that sink in. If Smolin’s theory is true, our universe exists the way it does because of a cosmic natural selection between universe’s within a multiverse of universes with different physical laws.
But all theories need empirical evidence. There is currently no evidence for the existence of either a multiverse or successive generations of universes that transmit their fundamental constants. And it’s possible we won’t have that evidence in the near future (or ever).
Either way, I’m optimistic. Advances in physics theory are likely to further support the idea of a multiverse and the CNS. And I wouldn’t bet against CNS being lifted from theoretical obscurity. The idea has a certain Copernican principle to it. Just as scientific inquiry revealed that our planet, solar system, and galaxy were not particularly special, it seems increasingly likely that scientific inquiry will do the same for our universe as well.
Discuss this on Hubski or let me know what you think on Twitter!