Really quite stunning. I liked Manifold: Time but found it occasionally uneven and that it didn't entirely fit together. But this book was a lot better (and I recommend starting with it, there's no sense in which this is a sequel).

Manifold: Space is an exploration of the Fermi Paradox -- why we don't see life elsewhere in the universe. And the answers it gives are quite chilling but ultimately hopeful. It is as much about evolution as physics as it explores the adaptations of humans living everywhere from Mercury to Triton -- not to mention the other non-carbon based life forms the star travellers find throughout the universe, in many cases dead or dying from violent expansionary cultures and ultimately recurrent physical phenomenon themselves.