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The five great eras of the cosmos

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korder's picture
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The five great eras of the cosmos

It has been widely accepted that the universe came into being through an inflationary event called the "Big Bang" some 13.8 billion years ago. It started as a fusion of gas and energy with temperatures on an unimaginable scale before cooling and settling down into the structures like galaxy clusters, galaxies, stars etc. which we see today.

The five eras of the cosmic evolution can be broadly classified as:

1) The dark era - This was the time when there was no light and the universe was opaque. There were no stars.

2) The Stelliferous era- The era of starlight started approximately 200 million years after the big bang and the cosmic dark age.

3) The degenerate era - This era will start approximately 100 trillion years from now, when the last red dwarf will burn out leaving degenerate matter like dead stellar corpses like white dwarfs, neutron stars and black holes in the cosmos.

4) The Black Hole era - This era will be utterly dominated by ravenous, ultra-massive black holes which will gulp all matter in their host galaxies and will continue from 10 raised to 40 years to a google years (10 raised to 100) with the evaporation of the last ultra-massive black hole and will signal the end of the universe 

5) The Dark era - The arrow of time would have come to an abrupt stop in this era probably and entropy would have reached its maximum possible value with no change happening in the cosmos. This will be the final end of our universe as we know it, unless there is a quantum fluctuation or something which can re-initiate another big bang...

To know more about the future of our cosmos and whether dark energy will dominate over dark matter (which it seems at the moment at least), our best bet would be to create micro black holes by smashing high energy particles at the Large Hadron Collider and understand their properties and evolution..

I know this topic is based on our current models hence many different explanations/discussions are possible

Xilman's picture
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Big Bang

I like Douglas Adams' take on this:

“In the beginning the Universe was created. This has made many people very angry and has been widely regarded as a bad move.”

Xilman's picture
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Dark era

A more serious response this time.

In my view, the arrow of time would not stop, abruptly or otherwise. Everything other than photons, neutrinos, electrons and positrons would have decayed (we do not presently know enough about dark matter if it exists and supersymmetrical particles --- if any -- to know whether they are stable). However, positronium atoms would still be around, albeit with a typical size of a parsec or more. Plenty of opportunities for them to interact and form structures.  So what if it takes petayears for each interaction?

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Cosmological eras

I believe myself that what we call the Universe was created when a microwave oven overheated in a Metauniverse, so creating what we know as the Big Bang.