“...theoretical physicist Lee Smolin argues that fundamental physics — the search for the laws of nature — losing its way. Ambitious ideas about extra dimensions, exotic particles, multiple universes,...”
I talked with him for about 30 minutes several years ago about his idea that there were multiple universes that evolved and that this would explain a universe seemingly designed for humans. Basically, the idea was that black holes are the birth place of new universes and that they pass their fundamental constants on to the baby universe. However, the constants can be slightly modified during the transition. Since stars make black holes, he argued that the “multiverse” (my word not his) selects for universes that produce a lot of stars because they will have a lot of baby universes. To have a lot of stars requires fundamental constants as in our universe. QED.
Of course it’s like life. You have to get to the first self-replicating molecule for evolution to start working. In universes, you’d have to get to the universe that has the first star.
It sounds like his thinking has evolved since then.
The book is more a critique on theoretical physics community with regard to string theory, and less about his own work.
After reading the book, my first big takeaway is that string theory is really not one theory, but an overarching set of theories, some contradictory to each other and to the background independent space-time models. Also, none of these theories can be falsified, since there are so many variables that can be "tuned" to meet the outcomes of any test.
The second is that string theory is such a predominate force in the theoretical physics community that it shuts out funding for other competing theories, such as his loop quantum gravity theory.
I do remember him discussing the evolving multiverse stuff in his book, but that is only a short section of the total. I would highly recommend the book, and if you read it, I would be interested in what you think about it.
Regards,
K51