Comments about "Primordial black hole" in Wikipedia

This document contains comments about the document "Primordial black hole" in Wikipedia
In the last paragraph I explain my own opinion.



The article starts with the following sentence.
A primordial black hole is a hypothetical type of black hole that is formed not by the gravitational collapse of a large star but by the extreme density of matter present during the universe's early expansion.
It is interesting to study the words "hypothetical", "theoretical", "predicted" and "speculated" in the documents of wikipedia.
IMO they mean all the same. They all describe concepts which can be false.
It has been proposed that primordial black holes, specifically those forming in the mass range of 10^14 kg to 10^23 kg, could be a candidate for dark matter.
See Reflection 1 - Pmc's as a possible solution for the dark matter issue.

1. Creation

According to the Big Bang Model, during the first few moments after the Big Bang, pressure and temperature were extremely high.
What this model more or less shows that the starting point of the Big Bang was a Black Hole. The problem here is what in this context means pressure and what means temperature.
Under these conditions, simple fluctuations in the density of matter may have resulted in local regions dense enough to create black holes.
You can easily write this, but is it true.
What are simple fluctuations? How do they start?
When there are fluctuations the universe becomes non-uniform.
Also what are the implications with the inflation theory.
Although most regions of high density would be quickly dispersed by the expansion of the universe, a primordial black hole would be stable, persisting to the present.
A primordial black hole of a certain mass is as stable (or instable) as a normal baryonic object of the same mass. With stable I mean life cycle time. They both can be captured by a Sun like object or a massive BH like in the center of our Milky Way.

2. Possible detection

One way to detect primordial black holes is by their Hawking radiation.
But than you first have to prove that Hawking radiation is an unique signature of a Black Hole.
Stephen Hawking theorized in 1974 that large numbers of such smaller primordial black holes might exist in the Milky Way in our galaxy's halo region.
In principle, as a matter of argument, they can also exist in the disc of our Galaxy.
All black holes are theorized to emit Hawking radiation at a rate inversely proportional to their mass.
This is a sentence which makes to claims. The first one is the most important.

3. Implications

4. String theory

5. See also

Following is a list with "Comments in Wikipedia" about related subjects

Reflection 1 - Pmc's as a possible solution for the dark matter issue.

The Galaxy Rotation Curve is curve which describes the average speed of the stars around the center of a Galaxy as a function of distance. The GRV can directly be calculated by measuring the speed of the stars (doppler shift). The GRV can also be calcuted as a function of the visibility or mass of stars in each region of the Galaxy. The two curves do not match. That means a certain amount of mass is missing or invisible. To solve this problem the concept of dark matter is introduced.
In the classical solution dark matter is proposed to be non-baryonic. In this document the solution is: Primary Black Holes.


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Created: 9 April 2016

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