Difference between micro black hole and primordial black hole

In summary: Hawking radiation is due to the presence of the event horizon. Only if you can create a situation where the HUP applies AND a black hole is present will you be able to get particles moving at faster than c. The only way we know how to do that is to put the black hole inside the HUP. But since we don't know how to do that, it's a moot point.In summary, Stephen Hawking discovered that particles can escape from a black hole through a process called Hawking radiation, which is based on the uncertainty principle. This means that smaller black holes can emit particles at a faster rate than larger ones, and could potentially be detected. Primordial black holes, formed in the early universe, could also emit particles
  • #1
dheeraj
8
0
If the amount of hidden information inside a black hole, depends on the size of the hole, one would expect from general principles, that the black hole would have a temperature, and would glow like a piece of hot metal. But that was impossible, because as everyone knew, nothing could get out of a black hole. Or so it was thought, but stephen hawking discovered that particles can leak out of a black hole. The reason is, that on a very small scale, things are a bit fuzzy. This is summed up in the uncertainty relation, discovered by Werner Heisenberg in 1923, which says that the more precisely you know the position of a particle, the less precisely you can know its speed, and vice versa. This means that if a particle is in a small black hole, you know its position fairly accurately. Its speed therefore will be rather uncertain, and can be more than the peed of light, which would allow the particle to escape from the black hole. The larger the black hole, the less accurately the position of a particle in it is defined, so the more precisely the speed is defined, and the less chance there is that it will be more than the speed of light,. A black hole of the mass of the sun, would leak particles at such a slow rate, it would be impossible to detect. However, there could be much smaller mini black holes. These might have formed in the very early universe, if it had been chaotic and irregular.these are what called primordial black holes, aren't they?

then in what way a micro black hole is different from a primordial black hole?
 
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  • #2
I don't think Hawking radiation is the result of particles traveling faster than light.

As for the difference between the two types of black holes, I think the only difference is that primordial black holes formed in the very early universe, whereas micro black holes are simply small black holes, irrelevant of how they formed. A primordial black hole could be a micro black hole and vice versa.
 
  • #3
What Hawking's ia saying is that if a particle or anti particle pair came into existence near the horizon of a black hole it can fall into the black hole and the other particle could then escape the black hole. It would then appear as radiation. He isn't implying that particles could just escape a black hole at any time.
Yeah the only difference between the two black holes are that a primordial black hole was formed at the beginning of the universe and not by the collapse of a star. It was formed by the density of matter durning the expansion of the universe.
 
  • #4
Here is the deal, no black hole can form in the present day universe via natural processes that is not at least around 5 solar masses. That is what the observational evidence implies. So, micro and primordial black holes can only form under exotic conditions. Primordial black holes are considered a possibility because conditions in the early universe are unclear. There are no known exotic conditions that can produce micro black holes.
 
  • #5
dheeraj said:
If the amount of hidden information inside a black hole, depends on the size of the hole, one would expect from general principles, that the black hole would have a temperature, and would glow like a piece of hot metal. But that was impossible, because as everyone knew, nothing could get out of a black hole.
That does not make it impossible, just unobservable. Black holes could very well be extremely dense quark-gluon plasma soup, but gravity is so great that none of the electromagnetic radiation can escape, except in the form of Hawking radiation.

dheeraj said:
Or so it was thought, but stephen hawking discovered that particles can leak out of a black hole. The reason is, that on a very small scale, things are a bit fuzzy. This is summed up in the uncertainty relation, discovered by Werner Heisenberg in 1923, which says that the more precisely you know the position of a particle, the less precisely you can know its speed, and vice versa. This means that if a particle is in a small black hole, you know its position fairly accurately. Its speed therefore will be rather uncertain, and can be more than the peed of light, which would allow the particle to escape from the black hole. The larger the black hole, the less accurately the position of a particle in it is defined, so the more precisely the speed is defined, and the less chance there is that it will be more than the speed of light,. A black hole of the mass of the sun, would leak particles at such a slow rate, it would be impossible to detect. However, there could be much smaller mini black holes. These might have formed in the very early universe, if it had been chaotic and irregular.these are what called primordial black holes, aren't they?

then in what way a micro black hole is different from a primordial black hole?
Primordial black holes are certainly possible. They would had to have formed prior to the end of the Hadron epoch (10-6 seconds after the Big Bang). Before the universe had the opportunity to cool off below 1013° K. Primordial black holes smaller than ~7.34 × 1022 kg in mass (about the mass of the moon) would have evaporated in the 13.78 billion years since the Big Bang.
 
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  • #6
dheeraj, your whole concept of particles moving faster than c due to the HUP is nonsense. You have either been badly misinformed or you misunderstood what you read.

Also, as has already been pointed out, the HUP has nothing at all to do with Hawking radiation.
 

Related to Difference between micro black hole and primordial black hole

1. What is the main difference between micro black holes and primordial black holes?

Micro black holes are formed from the collapse of massive stars, while primordial black holes are thought to have formed in the early universe from fluctuations in density. This means that micro black holes are much larger and more massive than primordial black holes.

2. How do their sizes compare?

Micro black holes can range from a few nanometers to the size of a small asteroid, while primordial black holes are thought to be much smaller, ranging from the size of an atom to the size of a mountain.

3. Can micro black holes be created on Earth?

No, micro black holes cannot be created on Earth. The conditions necessary for their formation are not present on our planet. Micro black holes can only be created through processes such as the collapse of a massive star.

4. Are primordial black holes a potential threat to Earth?

No, primordial black holes are not a threat to Earth. They are thought to be very small and would pass through the planet without causing any damage. Additionally, there is no evidence that primordial black holes even exist.

5. How can we distinguish between micro black holes and primordial black holes?

The main difference between micro black holes and primordial black holes is their formation and size. Micro black holes are much larger and can be observed through their effects on surrounding matter, while primordial black holes may be too small to be detected directly and can only be inferred through their gravitational effects on other objects.

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