Blackholes, Jets and Dark Matter.

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Discussion Overview

The discussion revolves around the mechanisms of jets ejected from supermassive black holes, the relationship between dark matter and matter, and the implications of matter-energy conversion. Participants explore theoretical aspects of black hole physics, including escape velocities, the nature of jets, and the potential interactions between dark matter and matter.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants question how matter can escape a black hole if the escape velocity is the speed of light, noting that jets are ejected at 99% the speed of light.
  • One participant asserts that matter ejected from a black hole does not cross the event horizon, allowing it to escape the gravitational pull.
  • There is a discussion about the potential interaction between dark matter and regular matter, with some suggesting that this could lead to energy being produced when they "cancel each other out."
  • Another participant clarifies that the concept of matter canceling itself out may refer to antimatter rather than dark matter, citing Einstein's equation E=mc² as a basis for matter-energy conversion.
  • One participant expresses confusion between dark matter and antimatter, acknowledging a lack of knowledge on the topic.
  • A later reply proposes that matter spiraling around a black hole may be ejected due to its inertia before being engulfed, raising questions about the dynamics involved in jet formation.

Areas of Agreement / Disagreement

Participants generally agree that jets are not emitted from within the event horizon of black holes, but there is disagreement regarding the nature of the matter involved and the mechanisms behind jet formation. The discussion remains unresolved regarding the interactions between dark matter and matter.

Contextual Notes

There are limitations in the discussion regarding the definitions of dark matter and antimatter, as well as the assumptions about energy conservation in the context of matter-antimatter interactions. The dynamics of jet formation and the exact processes involved are not fully explored.

Who May Find This Useful

This discussion may be of interest to those studying astrophysics, particularly in the areas of black hole physics, dark matter, and high-energy astrophysical phenomena such as active galactic nuclei (AGNs).

blimkie.k
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this topic relates to my post in a threat relating to GLAST
https://www.physicsforums.com/showthread.php?t=240620

Super massive black holes eject jets of matter back out into space. The matter in these jets shoot out of the black hole at 99% the speed of light. However the escape velocity for a black hole is the speed of light so how could any type of matter wheter it being gas or radiation escape a black hole propagating at just under the speed of light.

If the jets are a form of radiation wouldn't that mean it would be traveling the speed of light because that's the speed radiation and light travel. Also what happens to an object trying to escape the event horizon traveling exactly the speed of light ie. black hole escape velocity. I guess it falls in considering light itself can't escape the horizon.

I have read that dark matter could possibly interact with matter and the result would be the two canceling each other out and then being converted into pure energy

Matter canceling itself out and converting to energy violates conservation of mass because matter is destroyed and also violates conservation of energy because energy is created so that is also odd.

" some scientists think dark matter is in the form of massive objects, such as black holes" http://www.eclipse.net/~cmmiller/DM/

If dark matter lurks in black holes is it possible that as matter from a galaxy is pulled into the balckhole it reacts with the darkmatter canceling one another out and creating energy which is then ejected out of the black hole back into space or the energy could be responsible for propelling whatever matter the jets are made up of back out into space.

I tryed to pot some links to where i read about dark matter canceling matter but can't remember where it was. Maybe someone can post some literature.
 
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blimkie.k said:
Super massive black holes eject jets of matter back out into space. The matter in these jets shoot out of the black hole at 99% the speed of light. However the escape velocity for a black hole is the speed of light so how could any type of matter wheter it being gas or radiation escape a black hole propagating at just under the speed of light.

There is no escape velocity for somthing within the event horizon of a black hole. The matter that gets ejected never enters the event horizon, and therefore can escape at whatever speed is necessary to clear the gravitational well.

I have read that dark matter could possibly interact with matter and the result would be the two canceling each other out and then being converted into pure energy

Matter canceling itself out and converting to energy violates conservation of mass because matter is destroyed and also violates conservation of energy because energy is created so that is also odd.

I think you're referring to anti-matter and not dark matter. So, operating on that assumption...

Nothing is violated because of Einstein's famous equation E=mc^2. That demonstrates that matter can be converted into energy and the reverse also holds true. We've done both of these things here on earth.

If dark matter lurks in black holes is it possible that as matter from a galaxy is pulled into the balckhole it reacts with the darkmatter canceling one another out and creating energy which is then ejected out of the black hole back into space or the energy could be responsible for propelling whatever matter the jets are made up of back out into space.

Again assuming that you mean anti-matter as opposed to dark matter:

Although it is true that they do destroy each other when anti-matter and matter collide, I believe the general consensus in the scientific community is that there really is no appreciable amount of anti-matter flying around the universe. If there was, it would be very likely that it would have interacted with "regular" matter by now.

Even if there was, and the scenario you described occurred, it still wouldn't allowing anything to escape from the event horizon because the escape velocity from that point is greater than the speed of light.
 
Your absolutely correct i was confusing anti matter and dark matter i have limited knowledge on the subject so i thought they were the same thing.
Yea i guess i just realized the matter to energy conversion i believe that happens everyday when i eat food and the calories are converted to energy haha
Thanks for clearing up the part about the jets being ejected from the balck hole i thought they were actually coming from within the black hole past the event horizon.
 
Hi...
What I could get from this discussion is that there is black hole at the centre and since the matter of jet is not actually coming from the BH itself so what I thought is that the matter which is spiralling around it at very high speeds is ejected out due to its inertia before it is engulfed by the BH. Am I right? If not ..please tell what leads to matter to move at such high speeds in a beamed path. I have a keen interest in astrophysics specially AGNs.
 

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