Question on Black Holes

When an object gets sucked into a black hole, the only way we can detect it is through a barely detectable ammount of radiation escaping from it, because all the light from the object being taken in is also dragged in by the black hole. My question is, how then does one form or radiation (light) get pulled in by the intense gravity but another form of it escapes? Sorry if the facts are wrong, going by memory of a few astronomy books I've read.

 

Log in or Sign up to hide all adverts.

You might be talking about this....
http://en.wikipedia.org/wiki/Hawking_radiation

Other then that, when a black hole is close enoguh to a star, it gets messy......

Please Register or Log in to view the hidden image!

 

Log in or Sign up to hide all adverts.

Thanks for the link Truthseeker, the book didn't go into a lot of detail about how this happens.

 

Log in or Sign up to hide all adverts.

When an object is attracted by a black hole, it spins around it in the so-called "accretion disk". During this stage, the accretion disk emits great amounts of X-rays. When the object surpass the event horizon, no radiation emanating from it can escape outside the horizon

 

I believe the so-called 'object' you're talking about is probably in the form of gas or dust hitting the rapidily rotating accretion disk at a very high accelerated speed. This in turn creates very high temperatures and thus as a result, X-rays are formed. Allas, an X-ray source and a 'possible' Black Hole depending upon what it's original stellar mass was.

Okeydoke

 

I haven't heard ever that fision is produced when gas falls into the accretion disk. I suspect that the word that you wanted to use was friction

 

The tremedous super-heated temperatures that are produced as the gas & dust 'hit's' the accretion disk and funnels into the supermassive Black Hole, thus produces the artifact X-rays.

Okeydoke

 

does anyone know if Hawking radiation has anything to do with this mysterious Zero point energy?

i Heard it can produce matter antimatter pairs near the edge of a particle of atomic mass 173, which is impossible for a particle but i'm curious about whether black holes could achieve this.

 

Not sure what you mean, exactly, here.
Can you explain a little further, please?
Do you have any links to this idea?

 

Yeah,
i remember reading a recent paper that describe that black hole as a Dark energy/zero point energy production factory.
Perhaps they are related.
(Search this forum about hawkings radiation)

I haven’t got a link to it, but it did seem quite plausible – considering that we know virtually nothing about dark energy.

Please Register or Log in to view the hidden image!

It was thought that the zero point energy is a vacuum energy (the energy of empty space) that kept gravity from pulling the universe in on itself: A sort of cosmological constant.
A problem with this is that, it is now thought, that the cosmological constant is, er, isn’t constant (ie with the same energy density, pressure, and equation of state over time).
Models of the early universe require that the amount of Dark energy had to be quite small in the earliest stages; otherwise the formation of the large structures of in the universe would not appear as they do today, and quite big today.

Today, dark energy, as has been said, makes up 70 % of the content of the universe; it dominates over the matter content.
This means dark energy will govern expansion and determine the fate of the universe.

Several theories have been proposed for how dark energy might interact with the universe. My favourite is that it could be that as the universe expanded, the material density decreases, and some sort of `frozen` scalar field (the zero point energy that is under tension - frozen - and exerting a negative pressure that counteracts the positive pressure of gravity) is released.
The tension is released in the scalar field, and the value converges towards a `constant` value that dictates the expansion rate that we see today (Einstein's cosmological constant).
Or it could be that the scalar field has been rolling downwards into a `lower state` since the universe underwent inflation (and not reliant on matter density), and as it nears the bottom it starts to dominate the universe it automatically becomes a constant value.

 

Maybe all those explanations are too complicated....
Maybe this is like those times when we discovered tons of subatomic particles...
Then someone comes and "invents" the quark. Maybe the same is going to happen in the astrophysics field.....

Who knows.....

Please Register or Log in to view the hidden image!

Yaba Daba :m:

 

Fission has nothing to due with the great out put of many EM wave frequencies (radiowave noise, microwave waves, light, UV, soft and hard X-rays, and even gamma rays) that come when gas is being eaten by a black hole. (I.e. quasar radiation is not related to fission.)

(1) Fission requires elements with atomic numbers greater than Iron. (A=26) 99.999+% of everything falling into the black hole has much lower A. Probably 99% has A = 2 or less, I.e. is hydrogen or helium!

(2) Fission can convert mass into energy only with low efficiency. The mass difference between the original elements and the daughter elements is all you can get. I think, based on memory (to lazy to look up several differences.), 4% is maximium conversion efficiency possible. Quasar conversion rates can be ten times higher. That is, 40% of the mass entering can be radiated away as energy prior to the remaining mass disapearing over the event horizon.

 

I believe the radiowave noise events (peak to valley) measured across the central area (opening) of supermassive accretion disk of M-87 is approx. 22 light hours with the accretion disk itself being somewhere around 400+ light years* across.

*http://csep10.phys.utk.edu/astr162/lect/blackhole/blackhole.html

Okeydoke

 

That's a very big accretion disk. The accretion disk of the Black Hole at the center of the Milky Way has a diameter equal to the orbit of Jupiter (so less than a light year)

http://www.nrao.edu/pr/2000/sagastar/

 

At this point, the 2.5 + billion solar mass Supermassive Black Hole in M-87 'could be' ( I reiterate 'could be') the largest Supermassive Black Hole found to date. However, there may be even bigger 'monsters' out there still waiting to be found. I suspect there 'may be' Supermassive Black Holes out there that could be on the order of 4 to 5 billion solar masses and maybe even larger, that may inhabit the core(s) of galaxies larger in mass than even M-87, which is already 10 to 12 times the size of our own Milky Way galaxy. Time will tell.

Okeydoke

 

Yep, I can confirm that the BH at the center of M87 is the most massive found to date. I also agree that is probable that some BHs with a greater mass can exist (after all, we are still in a the beginnings of modern astrophysical observations, and we have a lot to discover)

I don't know about the accretion disk of the BH of M87, but the BH of NGC 4261 certainly has an accretion disk with a diameter of 400 ly

Please Register or Log in to view the hidden image!

 

What's the deal with Okeydoke editing his old posts to get rid of his 'fission' statements?

Highly unethical.
If you made a mistake then own up to it. Don't try to cover your tracks.

 

You must be mistaken. I never said anything about 'covering up my own tracks'. I simply exercised an option (edit) here at the forum inorder to correct or add to the information I already posted. If you have a problem with it, then don't read, write or contribute to any more of the posts here. That way, no one will think you're stupid.

Okeydoke

 

My. Aren't you awfully sensitive. I'll call that exhibit B.

Anyway. Why should my having a problem with you breaching forum etiquette lead to my not reading, writing, or contributing to any posts here? And why would I be thought of as stupid because you're going around editing posts so that you don't look stupid by saying things that are erroneous?

I bet you wish you could edit other people's posts too, eh?

You never said anything about anything. Rather, you did it all rather sureptitiously. Hence the craven aspect of it. Rather than editing past posts to erase your mistakes, simply acknowledge the mistake.

Oh. Well. Carry on. No skin off my nose if you don't know how to act.

 

I would suggest you go back and review your own posts. Your statements you've made here are based on your vivid imagination, especially when it comes to Black Hole research. If you you have any note worthy contributions to make here at the forum, try to make them with some intelligence backing them up instead of pretending you know something about something you know very little about. In this case, it's supermassive Black Holes.

Okeydoke