Insufficient Complexity
With only three elements, the mixture was chemically poor. Even after it cooled enough for the nuclei to capture electrons and form neutral atoms, very little chemistry was possible. Helium is a noble gas. That means that atoms of helium do not combine with anything. Hydrogen atoms combine with one another two at a time to form hydrogen molecules. Lithium combines with hydrogen to form lithium hydride, a colorless crystal. At the end of the first morning the only available chemical substances were atomic and molecular hydrogen, helium, metallic lithium, and lithium hydride. These were insufficient to form the complex combinations needed for life. No known form of life can exist with so few elements and so few chemical substances.
Conditions had to be very different on the first and second mornings to make all the elements. Conditions also had to be just right on the first morning. With too much temperature and pressure most of the neutrons might have combined with the protons to make deuterium. That would have equalized the number of protons and neutrons almost irreversibly. Deuterium is not suitable for making elements much heavier than sulfur (16 protons and usually 16 neutrons) because the heavier elements require more neutrons than protons for stability. When the single protons of ordinary hydrogen combine with other nuclei, they can turn into neutrons to supply the extra number of neutrons the heavy elements need. Deuterium doesn’t combine as easily as protons with other nuclei, and the proton of a deuterium nucleus doesn’t turn into a neutron easily. Without heavy elements there would be no iron (26 protons and usually 30 neutrons) to carry oxygen in the blood, for instance. On the other hand, if the pressure had been too low at the start or had not stayed high long enough, most of the neutrons would have decayed into protons. In that case there could never have been any elements heavier than hydrogen.
Conditions had to be very different on the first and second mornings to make all the elements. Conditions also had to be just right on the first morning. With too much temperature and pressure most of the neutrons might have combined with the protons to make deuterium. That would have equalized the number of protons and neutrons almost irreversibly. Deuterium is not suitable for making elements much heavier than sulfur (16 protons and usually 16 neutrons) because the heavier elements require more neutrons than protons for stability. When the single protons of ordinary hydrogen combine with other nuclei, they can turn into neutrons to supply the extra number of neutrons the heavy elements need. Deuterium doesn’t combine as easily as protons with other nuclei, and the proton of a deuterium nucleus doesn’t turn into a neutron easily. Without heavy elements there would be no iron (26 protons and usually 30 neutrons) to carry oxygen in the blood, for instance. On the other hand, if the pressure had been too low at the start or had not stayed high long enough, most of the neutrons would have decayed into protons. In that case there could never have been any elements heavier than hydrogen.