The Four Ages of the Universe -- What's Next?

The Greek poet Hesiod described the Five Ages of Man in mythology.

They progress from the Golden Age, when people lived among the gods, through the warlike Bronze Age and on to the Heroic Age. His narrative ends with the Iron Age, a period of toil and misery for mankind.

Science has now replaced these mythologies. We are at the point where we look at the entire universe as a grand series of game-changing leaps toward our emergence as an intelligent species. It is an epic story more compelling than anything from creation mythology.

In a recent paper, Marcelo Gleiser of Dartmouth College describes the universe’s first three ages as the physical age, chemical age, and biological age. He says that we are now entering the cognitive age, the emergence of intelligence life on Earth and presumably across the universe.

This leaves us with an enticing question: what will be the fifth age of the universe? Will this be a period of decline toward the burnout of the last star, as our extrapolations from current astrophysics predict? Or could it be something more existential and unpredictable given the potential influence of "thinking matter" on the arrow of time? Are we entering a cosmological Age of Aquarius?

Knowing Our Place in the Universe

Advances in astronomy over the past several decades allow us to precisely retrace the four ages of the universe to the present. We are the first generation to know the geometry, material composition, and evolution of the universe.

This has been largely accomplished by the discovery of the cosmic microwave background and large-scale telescopic surveys of the distribution of galaxies in space and time.

Within only the past 50 years we have learned that life as we know it relies on chemical elements forged in dying heavy stars. The first stars formed perhaps as early as 200 million years after the Big Bang. They forge the heavy elements in a fireworks finale of supernova explosions. We are confident that chemically-enriched second generation stars went on to build a plethora of stable planetary systems.

Some fraction of planets became astrobiological "Petri dishes" for biochemical reactions. The hallmark of the biological era is the still unknown leap from dormant matter to self-replicating matter. This remarkable process is driven by complex molecular nanomachines storing and reprocessing information under Darwinian rules.

But is Gleiser's cognitive era isolated to Earth? It presumes intelligent life could be co-emerging among the myriad stars and galaxies. At present it's probably simplest to say that the vast gulf of time and space keeps us in cosmic isolation, if not quarantine, from fully answering this question.

This leads me to the idea of a fifth age for the universe, yet to be realized. Perhaps intelligent entities can evolve to have mastery over entire galaxies, as predicted by the Soviet Russian astronomer Nikolai Kardashev in 1964. He imagined that through extraordinary astroengineering projects, far advanced aliens might reshape a galaxy to their liking. They may tap energy off the galaxy's central black hole and construct artificial habitats free of destruction from cosmic catastrophes.

Read more at Discovery News