How did the universe make it possible for us to be here, having this conversation? Is our universe special, out of many possibilities, with just the right values of the constants of nature to support complex carbon-based life? Or is there a reason for the constants to have the values we observe? Our standard models of particles and cosmology seem to fit almost everything we know, but we don’t understand the connection between relativity and the quantum world. And cosmology requires at least two surprising parts, dark matter and dark energy.
How did those particles produce life? We can tell the story of how the galaxies grew, how they made stars, how the stars made the elements of life, and how the interstellar materials made new stars with planets like ours. But there seems to be a universal pattern, of complexity arising from simplicity, feeding on energy flows as spontaneously arising heat engines. What does this tell us about the possibilities of life elsewhere? Is it inevitable, or rare?