The anthropic principle and the evolution of the universes

This is a short note on the current controversies concerning the formation of our Universe, developed in the book What is your dangerous idea?. Recent research has come to the conclusion that for our present Universe to exist, the so-called 'universal constants' have to have precise values, otherwise, the formation of galaxies and stars would not occur at a pace for life to exist. Furthermore, string theorists are discovering that there is not a single solution (and a unique set of 'universal' constants) but a 'landscape' approaching 10⁵⁰⁰ solutions and there are thus maybe many other universes with different constants that lay beyond the limit of our own!

Those conclusions, although yet highly speculative, are in the same time 'exciting and humbling' according to Brian Greene, and I would add unsettling for some. Why unsettling? First, because it poses the fundamental question of the existence of our Universe and why we were so lucky in the first place that life can exist. One rhetoric is to state that it is not really luckiness because if our Universe would have different 'universal' constants, life would not exist and we would not be here to complain that we were not lucky: this is the so-called anthropic principle.

The second and most unsettling point of those conclusions is the realization that the idea of a 'universal' set of laws that would dictates all universes, laws that are fundamental and are at the bottom and origin of everything, might not exist. Instead, these laws would be valid only locally and be pure environmental facts:

"Well, [thoses ideas] do threaten physicists' fondest hope-the hope that some extraordinarily beautiful mathematical principle will be discovered that would completely and uniquely explain every detail of the laws of particle physics.
[...] What further worries many physicists is that the landscape may be so rich that almost anything can be found-any combination of physical constants, particle masses, and so forth. This, they fear, would eliminate the predictive power of physics. Environmental facts are nothing more than environmental facts. They worry that if everything is possible, there will be no way to falsify the theory-or, more to the point, no way to confirm it."

Leonard Susskind, The "landscape", in What is your dangerous idea?

"The end of «fundamental» theoretical physics (the search for fundamental microphysical laws-there will still be lots of work for physicist who investigate the host of complex phenomena at larger scales) might very well occur not with a theory of everything but with the recognition that all so-called fundamental theories that describe nature are purely phenomenological-that is, derivable from observational phenomena-and don't reflect any underlying grand mathematical structure of the universe which would allow a basic understanding of why the universe is the way it is."

Laurence M. Krauss, The world may be fundamentally inexplicable, in What is your dangerous idea?

I will conclude with two other ideas that, without resolving the problem and erase any controversy, are not the less interesting. One, presented in the book by Paul Steinhardt, is to make the assumption that the 'universal' constants are not constant but vary slowly with time, so slowly that 1) our universe had time to have shrink and expand cyclically many times already (which would suggest that the Universe is much older than actually thought) and 2) we have not yet been able to measure their variation. Accepting this assumption avoid to call for other universes. Instead, one universe, our own, would slowly drift across different regimes of the 'landscape' and the one we are now is just the one at a particular time.

The second and bolder idea, presented by Lee Smolin, is to see our present universe and its 'universal' constants not as a result of chance, but a result of natural section. The idea is to apply Darwin's ideas of selection and co-evolution to even the fundamental laws and constants. If true, the theory poses, as usual, new questions; for instance, is there a meta-law, like the second law of thermodynamic, that would dictate how laws evolve? Smolin concludes that if the theory, which can be falsifiable, come to be true

"Einstein and Darwin will be understood as partners in the greatest revolution yet in science, a revolution that taught us that the world in which we are embedded is nothing but an ever-evolving network of relationships."

Lee Smolin, Seeing Darwin in the light of Enstein;seeing Einstein in the light of Darwin, What is your dangerous idea?