Tell me what you know about Black holes

[Spec]

Originally posted by KrazyHorse


Not just can it happen, but I spent an hour or so talking to a woman who spends her time simulating these collisions on a computer yesterday.

These collisions are going to be a major source of gravitational waves which should be detected by LISA if and when it ever flies.

From what distance? What impact would it have on a planet such as ours?

And:

If an even greater amount of mass is contained within the same space, even the Pauli force between nucleons cannot resist gravity and the body collapses into itself forming a black hole. In a way that can be hard to imagine, nothing can stop this collapse if enough matter gets into a small enough space, and the matter collapses to a point of zero height, width, and depth, known as a singularity.

that, I really dont understand.

Spec.

[Proteus_MST]

Sounds to me not unlike the explantion I gave:

Physical insight on the process may be gained by imagining that particle-antiparticle radiation is emitted from just beyond the event horizon. This radiation does not come directly from the black hole itself, but rather is a result of virtual particles being "boosted" by the black hole's gravitation into becoming real particles.

A more precise, but still much simplified view of the process is that vacuum fluctuations cause a particle-antiparticle pair to appear close to the event horizon of a black hole. One of the pair falls into the black hole whilst the other escapes. In order to preserve total energy, the particle which fell into the black hole must have had a negative energy (with respect to an observer far away from the black hole). By this process the black hole loses mass, and to an outside observer it would appear that the black hole has just emitted a particle

Although I have been wrong in generally equating the antiparticle with antimatter.

[Ari Rahikkala]

Originally posted by KrazyHorse
Whether or not all the matter in the universe would eventually end up in black holes is a tricky question. You actually have to simulate the evolution of large scale structure and the growth of black holes to see what happens. This behaviour is not inherently obvious from first principles as far as I can tell.

Actually, assuming the universe never stops growing, then the cosmic background will eventually become colder than even the most massive black holes, making every black hole eventually start losing mass and finally evaporate. Right? I have no clue about the mathematics involved here, I've just been reading Wikipedia...

[KrazyHorse]

Originally posted by Spec


From what distance?

Redshifts up to ~1 IIRC (billions of light years)

What impact would it have on a planet such as ours?

None. If two supermassive black holes collapsed at the centre of our galaxy then we might be in trouble, but not just from gravity waves...

that, I really dont understand.

No ****. There's no real point to you guys attempting to understand the mechanisms behind such processes. You don't have the prerequisite knowledge to make any sense of it.

[KrazyHorse]

Originally posted by Ari Rahikkala


Actually, assuming the universe never stops growing, then the cosmic background will eventually become colder than even the most massive black holes, making every black hole eventually start losing mass and finally evaporate. Right? I have no clue about the mathematics involved here, I've just been reading Wikipedia...

If dark energy is a true cosmo constant then this is true. However, it's avoiding the question. Will all matter be absorbed before this happens? If it is then you end up with a universe with 0 matter, very low radiation density and significant D.E. density. If not then you end up with extremely low radiation density, low matter density and significant D.E. density.

Either way, of course, D.E. continues to dominate further and further. That much is obvious. The rest is not.

[KrazyHorse]

Originally posted by Proteus_MST
Sounds to me not unlike the explantion I gave:


Although I have been wrong in generally equating the antiparticle with antimatter.

The fact that you can't see the difference tells me that you should probably just give up right now.

[KrazyHorse]

The fact that the black hole loses mass has nothing to do with absorbing antimatter. It has to do with emitting a particle which is pulled out of the vacuum.

I just love watching non-physicists attempt to explain something which I'm not even qualified to explain fully.

[Last Conformist]

Originally posted by Proteus_MST
Sounds to me not unlike the explantion I gave:


Although I have been wrong in generally equating the antiparticle with antimatter.

It doesn't say it's the antiparticle falling into the hole. In fact, it the net result is the same whether the particle or antiparticle falls in.

[KrazyHorse]

The descriptions are eerily similar, LC.

After all, the prefix "anti" is in both explanations.

[Asher]

Quebec = Financial black hole

[Kuciwalker]

Is the anti-particle also antimatter? (Assuming that the first particle is matter.) Or are they always photons so it doesn't matter?

[Kuciwalker]

And if the anti-particle has negative energy, wouldn't it also have negative mass and be repelled by the black hole?

edit: I'm assuming here my understanding is incomplete, not yours/scientists, btw.

[KrazyHorse]

An antiparticle may be "matter" or "antimatter" (quotes because outside a certain group of particles it's not obvious that such a classification is either possible or worthwhile).

And no, it's not necessary that it only be photons...

[Last Conformist]

Originally posted by Kuciwalker
Is the anti-particle also antimatter? (Assuming that the first particle is matter.) Or are they always photons so it doesn't matter?

A black hole can 'emit' positrons and other antiparticles if that's what you mean.

[Ari Rahikkala]

Originally posted by KrazyHorse
No ****. There's no real point to you guys attempting to understand the mechanisms behind such processes. You don't have the prerequisite knowledge to make any sense of it.

The thing is, back in the day, ah, so long ago, when I was a little kid with endless time to pore over any book on any subject, none of the ones about physics (not that they had the most recent understanding on everything) ever contained any of this cosmic inflation or Hawking radiation or dark energy crap. Back then, the universe began from a singularity in the big bang and maybe had black holes which would never get smaller, and the expansion of the universe would always decelerate, perhaps even reverse. It was a simpler time, a simpler, more understandable physics, so long ago...

... I'm 21.

You guys should stop developing your field for a while so that the rest of the world can catch up .