A wide-ranging work of science and philosophy, centered around the idea that further progress in physics and cosmology will require the abandonment, already initiated by general relativity, of any conception of absolute space or time. Fantastic.

I'm no stranger to pop-science books but this book opened my mind to some amazing possibilities. How is it that the universe we inhabit has just the right properties for us to exist? The Anthropic principle says it must because we are here to observe it. Smolin suggests that, in a nutshell, in the beginning there was random nothing, then out of that came blind iteration - universes forming and collapsing again, until finally evolution emerged by chance (it had all the time in the world after all to do so) and one (or more) universes 'stuck', ie were just stable enough to give rise to offspring (in black holes). Each child universe inherits the properties of its parent, with some random mutation, and eventually one (or more) universe formed that is stable enough to give rise to us. This is the theory of cosmological natural selection. The idea that inside every black hole is another daughter universe of our own, and ours is, in turn, the guts of a black hole in some parent universe, is deeply attractive. This book expounds on this thought experiment in an highly accessible manner.

The best cosmology book I've ever read. Forget about tedious Elegant Universe, forget about that slapdash Brief History of Time, this is the book to read to get a an overview of our current understanding of the universe as a whole.
Obviously the main argument presented in this book, of cosmological natural selection, is nothing more than a hypothesis of truly fascinating potential and implication. But in presented the whole of his argument Smolin takes the reader on a whirlwind tour of space and time, how we know what we know about them, how we've gone about asking the questions and what that reveals about us, and the currently competing answers for the wildest questions humanity has ever dared itself to ask.

( read half of this )

Lee Smolin presents an interesting hypothesis that attempts to explain why the fundamental physical constants seem to be "tuned" perfectly to allow stars, planets, and life to evolve. The best aspect of his hypothesis is that it is "falsifiable". This means that Smolin proposes a number of tests that if they fail, would mean that his hypothesis is wrong. And, the tests are not incredibly difficult. He includes observational tests--like measuring the masses of additional neutron stars--and theoretical tests; calculating the consequences of changing the values of certain physical "constants". So, Smolin's hypothesis is quite engaging, and should be considered seriously.

But most of the book is not about Smolin's hypothesis at all. It is really about reconciling various quantum theories and cosmology. The book is deeply philosophical, and the book makes clear which parts are pure speculation. Smolin mentions that he met Richard Feynman a few times. Each time he described his work to Feynman, he was criticized because Smolin's ideas were not sufficiently crazy!

So, much of the book contains some crazy ideas, and it is full of philosophical speculation. The book is not easy to read--not because of heavy technical explanations, but because the philosophical viewpoints are often quite subtle.

I love Lee Smolin - he never seems to be afraid to push past assumption, to seek lines of inquiry outside of the narrow bounds of physics specialties and he doesn't lose his wonder in the world.

Right from the start, Smolin says this book is speculative. Not that it's founded on no science or bad science, but that he pushes "what if" into some areas that might blow our minds (my words).

Without giving too much away, he wonders whether or not the constants that we assume to be unchanging might actually be parameters that have changed slightly over time in a universe (universes) that actually is more like an ecosystem that evolves. Pretty cool stuff and lots of brain food.

Since we can't see what happens on the other side of a event horizon of a black hole, what if what actually happens is that a new universe is born there, and ours is just one in an evolutionary chain and our black holes are birthing others?

And how is it that our place, Earth, stays in a perpetual state that denies the law of entropy such that it can support life? i.e. non-equilibrium?

Ultimately this is also a book about how we might jump start our next inquiries into the Grand Unified Theory by rejecting that our assumptions that things like constants and atomic interactions have always been as they are.

Neat!