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Age of universe conondrum


Dimitri

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There is a conondrum in cosmology related to the 13.7 billion year estimate for the age of the universe. It is as follows: Quasars are estimated at distances approaching the age of the universe, and began emitting radiation (light) to our position close to 13 billion years ago. But according to big bang cosmology the universe had a beginning 13.7 billion years ago, space expanded along with the material from which Quasars were formed, and the universe was near its beginning compressed to a more confined, restricted dimension of space. The conundrum: How did Quasars escape from this earlier confined region of space to assume those position in space that the evidence (red shifts) indicate they occupied that long ago? They could not have been within this confined space and outside of it at the same time. Inflationary theory does not resolve this conondrum. Any suggestions?

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Quasars are not confined to a region of space, but rather a period of time.

 

In the early universe, hot, fast-burning giant stars at the centers of young galaxies collapsed into huge Black Holes. The relative closeness of these central stars provided for huge accretion disks to the Black Holes. During this 'active' phase the accretion disks spiralling into The BHs, created highly energetic polar jets of radiation, many thousands of times brighter than the galaxies themselves.

 

That era is now mostly over. The gigantic central BHs of most galaxies are now dormant, having 'gobbled-up' all nearby masses. They are not quite invisible though, as they are still ingesting some mass, and so are loud X-ray sources.

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"...How did Quasars escape from this earlier confined region of space to assume those position in space that the evidence (red shifts) indicate they occupied that long ago? They could not have been within this confined space and outside of it at the same time. Inflationary theory does not resolve this conondrum. Any suggestions?"

 

Could you please write this in other words? It is not clear or coherent.

 

Quasars are probably the first light after the big bang if supermassive black holes could have formed by a direct collapse rather shortly after the big bang. It took hundreds of millions of years after the big bang, after the cosmic dark ages, for the first stars to form. Then it took millions of years more for the first giant stars to supernova and create the first black holes.

Edited by Airbrush
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If a BH is due to stellar collapse, it will have a lower size limit ( Oppenheimer limit ? ) and this limit is large enough that no BHs could have evaporated ( via Hawking radiation ) in 13.7 bil yrs.

However if they were due to density variations in the early universe, and formed by direct collapse rather than going through the star phase, they could have any size, Airbrush.

That means that some of the microscopic ones would have evaporated already, while some slightly larger, would be evaporating as we speak. The final act of the evaporation of a BH, via Hawking radiation, occurs when there isn't enough mass left to sustain an event horizon. At this point the remaining mass is converted violently to radiation, and if this had, or was happening, we would detect the tell-tale gamma ray burst.

Nothing hs been detected !

 

The only way for micro BHs to survive evaporation is if every single one had become a 'seed' for galaxy formation, and would then have grown faster than its evaporation rate.

And this would again be due to the quasar mechanism.

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