...Historically, scientists have viewed the cosmos as akin to a rock—complex, perhaps even beautiful, but formed through arbitrary events. Evolutionary cosmologists instead argue that universes, like living organisms, grow and reproduce, spinning off new universes with small variations from their progenitors. In doing so, these cosmic offspring are refined across generations into forms that maximize the number of universes yet to be born. Since the Big Bang, our universe, like any developing child, has been unfurling into an optimal shape.

Under this view, the universe is not a rock. It is an egg...

Smolin’s work was, in turn, inspired by physicists Bryce DeWitt and John Wheeler, who proposed that singularities inside black holes, the places where matter is crushed into a point of infinite density, might expand to produce new universes that follow different physics from the universes that produced them. Every universe—including our own—would, under this logic, have emerged from a Big Bang within a black hole.

Smolin realized that this hypothetical process would allow universes to reproduce, in a way, by making more black holes. And if those new universes could inherit the physics of their parents with small differences—just as new organisms inherit the genes of their parents with small differences—then universes could also evolve with each generation. Specifically, a form of cosmic natural selection would favor universes that make as many black holes as possible. Less fertile universes could persist, but they would produce far fewer offspring. So over time, an increasingly high proportion of universes would be optimized for black hole production—which would imply that our universe, given the odds, is one of those...