The Singularity Is Nearer: When We Merge with AI

by Ray Kurzweil

If the nuclear strong force had been stronger or weaker, it would have been impossible for stars to form the large amounts of carbon and oxygen from which life is created.[58] Likewise, the nuclear weak force is within one order of magnitude of the minimum possible for life to evolve.[59] If it were weaker than this, hydrogen would have quickly turned to helium, preventing the formation of hydrogen stars like our own, which burn long enough to allow complex life to evolve in their solar systems. If the difference in mass between up quarks and down quarks had been slightly smaller or larger, it would make protons and neutrons unstable, preventing complex matter from forming.[60] Likewise, if electrons had a slightly larger mass relative to those differences, similar instability would result.[61] According to physicist Craig J. Hogan, “only a few percent fractional change in the quark mass difference in either direction” would have kept life from arising.[62] If the quark mass difference were greater, we would have a “proton world”—an alternate universe where only hydrogen atoms would be possible.[63] If the difference were smaller, we would have a “neutron world”—a universe with nuclei but no electrons around them, making chemistry impossible.[64] If gravity had been slightly weaker, there would be no supernovas, which are the source of the heavy elements from which life is formed.[65] If gravity had been slightly stronger, stars would have been much shorter-lived, making i...