DEEP TIME
DEEP TIME
The concept of deep time divides the whole of time into 5 eras”
DEEP TIME
1. The Primordial Era: Everything from the Big Bang to right when the first stars began to form. From 0 – 400 million years. The universe is a very hot soup of particles. As the universe cools these particles are able to clump together; from energy to fundamental particles to subatomic particles (electrons, neutrons, and protons) to hydrogen atoms. At the end of this era the hydrogen atoms have clumped together to form the first stars.
DEEP TIME
2. The Stelliferous Era: From 400 million years to now to 1013 years. This is the era when stars and groups of stars (star clusters, galaxies, galactic clusters) are the most numerous objects in the universe and the primaries producers of energy.
DEEP TIME
2. The Stelliferous Era: The lower the mass of a star the longer it will live. Current models indicate that the lowest mass red dwarf star will live for 1012 years.
DEEP TIME
2. The Stelliferous Era: As the hydrogen in the universe is depleted (converted to heavier elements) fewer and fewer stars will be born until stellar formation stops. Existing stars will eventually die out leaving only red dwarf stars to populate the universe.
DEEP TIME
2. The Stelliferous Era: Galaxies will become dimmer and redder as they are eventually composed of only red dwarf stars.
DEEP TIME
3. The Degenerate Era: 1013 – 1040 years. When the last red dwarf dies the only objects in the universe generating any energy will be white dwarfs, neutron stars, and black holes. Of these, white dwarfs and neutron stars are prevented from collapsing by degeneracy pressure; electron degeneracy pressure in the case of white dwarf stars and neutron degeneracy pressure in the case of neutron stars.
DEEP TIME
3. The Degenerate Era: Over time white dwarfs and neutron stars will cool, losing their energy too. During this time, binary white dwarfs and binary neutron stars will eventually collide and explode. These will be enormous, but short lived, energy bursts in an otherwise dark era.
DEEP TIME
3. The Degenerate Era: Recall that dark energy is accelerating the expansion of the universe and will likely win out over matter and dark matter. During this era space will have expanded so far as to make the universe unseeable to us. We would only see a very small part of the universe; maybe just our galaxy or a small part of it.
DEEP TIME
3. The Degenerate Era: All protons will have decayed in about 1034 years. By the end of this era all atomic matter will have disintegrated theoretically leaving only free neutrons and electrons.
DEEP TIME
4. The Black Hole Era: 1040 – 1092 years.
After about 1040 years black holes are the only objects in the universe.
Recall that a black hole is the singularity in the center. Since it occupies zero volume it would still exist no matter how much space had expanded.
DEEP TIME
4. The Black Hole Era: During this era black holes will actually evaporate. As their matter leaks out into infinitely expanded space it would immediately cease to exist.
e.g. a black hole with 3 solar masses would evaporate in about 1068 years.
DEEP TIME
4. The Black Hole Era: During this era black holes will actually evaporate. As their matter leaks out into infinitely expanded space it would immediately cease to exist.
e.g. a black hole with 3 solar masses would evaporate in about 1068 years.
e.g. the largest super massive black holes from the centers of galaxies would evaporate in about 1092 years bringing this era to an end.
DEEP TIME
5. The Dark Era: 1092 - ∞ years.
Big Freeze Version: If dark energy balances matter/dark matter then anything left just loses it energy and stops.
DEEP TIME
Other Options (purely conjecture, but not unreasonable):
Maybe we live in a multiverse where other universes will continue when we no longer do.
DEEP TIME
Other Options (purely conjecture, but not unreasonable):
Maybe our universe drops to a lower energy state of reality where it would restart. In this new lower-energy reality it has infinite energy whereas in our reality it had none. Maybe this is how our universe started in the first place…..a nearly infinite amount of energy bursting forth from nowhere. Sound familiar?