How The Life Begin

Before observations of dark energy, cosmologists considered two scenarios for the future of the universe. If the mass  density  of the universe were greater than the  critical density , then the universe would reach a maximum size and then begin to collapse. It would become denser and hotter again, ending with a state similar to that in which it started—a Big Crunch. Alternatively, if the density in the universe were equal to or below the critical density, the expansion would slow down but never stop. Star formation would cease with the consumption of interstellar gas in each galaxy; stars would burn out, leaving  white dwarfs ,  neutron stars , and  black holes . Very gradually, collisions between these would result in mass accumulating into larger and larger black holes. The average temperature of the universe would asymptotically approach  absolute zero —a  Big Freeze .Moreover, if the proton were  unstable , then baryonic mat...