The idea that certain aspects of our universe make it uniquely suited to life could well be an illusion, suggests Fred Adams of the University of Michigan in Ann Arbor, pointing out that “no one has done the calculations.”

So Adams selected a range of possible values for each of three basic constants involved in the formation of stars (the gravitational constant, alpha — the fine structure constant that determines the strength of interactions between radiation and matter, and a composite of constants that determines the reaction rates of nuclear processes) and put them into a computer model that created multiple universes (a multiverse). About a quarter of the stars gave out enough energy to power some form of life, and lasted long enough for life to evolve.

See also: The Anthropic Principle Under Fire