Mass/Energy of Relativistic Jets?

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Discussion Overview

The discussion revolves around the mass and energy of relativistic jets emitted from supermassive black holes. Participants explore various aspects of these jets, including their composition, the mechanisms behind their formation, and their potential impact on galactic dynamics. The conversation includes references to research articles and previous threads, as well as questions about the quantification of jet mass and energy.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation
  • Mathematical reasoning

Main Points Raised

  • Some participants inquire about the research conducted on the mass and energy contained in relativistic jets and whether this mass could exceed that of the galaxy.
  • There is uncertainty regarding whether the energy of the jets is primarily baryonic, leptonic, or electromagnetic field energy.
  • Participants discuss the conditions necessary for jet formation and the mechanisms that determine which objects can produce jets.
  • One participant suggests that relativistic velocity could multiply the rest mass of the jets, while others challenge this notion, emphasizing the distinction between rest mass and relativistic effects.
  • Concerns are raised about the lack of measurements for the accumulated mass of quasar jets and the implications for understanding dark matter and galactic rotation curves.
  • Some participants express confusion over terminology, particularly regarding baryons and the electromagnetic spectrum, leading to corrections and clarifications.
  • There are references to articles that provide technical details about black hole jets and their properties.

Areas of Agreement / Disagreement

The discussion remains unresolved with multiple competing views. Participants disagree on the significance of jet mass relative to galactic mass and the implications for dark matter. There is no consensus on the quantification of jet mass or its effects on galactic dynamics.

Contextual Notes

Limitations include the lack of empirical measurements for jet mass and energy, as well as unresolved questions regarding the conditions for jet formation and the role of dark matter in this context.

EskWIRED
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Supermassive black holes sometimes have extended relativistic jets emerging from the poles. They are HUGE and powerful and fast.

Has there been research into the mass of such jets? Any other impressive statistics about just how much mass and energy these things contain?
 
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EskWIRED said:
Supermassive black holes sometimes have extended relativistic jets emerging from the poles. They are HUGE and powerful and fast.

Has there been research into the mass of such jets? Any other impressive statistics about just how much mass and energy these things contain?

Jets are an enigma. The best we can do is refer you to a previous thread, easily findable through the tags function: https://www.physicsforums.com/showthread.php?p=4221199#post4221199
 
This article covers the jets in great and technical detail. Covers pretty much any measurable aspect of a black hole.

Foundations of Black Hole Accretion Disk Theory

http://arxiv.org/abs/1104.5499
 
Thanks for the thoughtful replies. I'm downloading now.
 
As I understand, we don't even know whether the energy of the jets is primarily baryonic, primarily leptonic, or primarily electromagnetic field energy.
 
phyzguy said:
As I understand, we don't even know whether the energy of the jets is primarily baryonic, primarily leptonic, or primarily electromagnetic field energy.

You might want to think about this statement as the electromagnetic spectrum includes both baryons (photons, neutrons) as well as leptons (electrons) .

What is poorly understood on jets are the conditions that allow jets, when do they occur, what mechanism determine which objects can have jets? How do jet knots form? What % of the infalling matter converts to the energy and angular momentum ejected via the jets.
 
Mordred said:
You might want to think about this statement as the electromagnetic spectrum includes both baryons (photons, neutrons) as well as leptons (electrons) .

What is poorly understood on jets are the conditions that allow jets, when do they occur, what mechanism determine which objects can have jets? How do jet knots form? What % of the infalling matter converts to the energy and angular momentum ejected via the jets.

I think you are confused on several points:

(1) Photons are not baryons.
(2) Neither neutrons nor electrons are part of the electromagnetic spectrum.
 
lol your right I screwed up for some oddball reason I mixed up proton and photon. Also I poorly worded my reply in regards of neutron. I included it as an example of baryon.

Not sure what I was thinking on this post must have been 3/4's asleep lol, long work day
 
  • #11
EskWIRED said:
Supermassive black holes sometimes have extended relativistic jets emerging from the poles. They are HUGE and powerful and fast.

Has there been research into the mass of such jets? Any other impressive statistics about just how much mass and energy these things contain?

I want to know if the accumulated mass of the jets could exceed the mass of the galaxy, and does this ejected mass included dark matter? Relativistic velocity would multiply the rest mass. With enough mass, this would profoundly affect the rotation of the galaxy and reduce reliance on a dark matter halo to explain the outer orbital velocities. If this has not been quantified, it remains a fascinating alternative explanation.
 
  • #12
patellar-myotatic said:
I want to know if the accumulated mass of the jets could exceed the mass of the galaxy
It is a tiny fraction of the mass of the galaxy, and does not include dark matter.
patellar-myotatic said:
Relativistic velocity would multiply the rest mass.
It does not. That's the point of "rest mass" (usually just called mass). It increases the energy, but not beyond the energy present before.
 
  • #13
patellar-myotatic said:
I want to know if the accumulated mass of the jets could exceed the mass of the galaxy, and does this ejected mass included dark matter? Relativistic velocity would multiply the rest mass. With enough mass, this would profoundly affect the rotation of the galaxy and reduce reliance on a dark matter halo to explain the outer orbital velocities. If this has not been quantified, it remains a fascinating alternative explanation.
If my word "profoundly" is not self-evident, let me elaborate. The ejected mass of the quasar jets have no effect at the center of the galaxy as the two jets presumably are symmetrical, have similar mass and cancel out. However, at any distance radially from the jet axis, their total mass is additive and gravitational "force" towards the axis increases proportional to the mass of the jets within a cylinder of that radius. Only after the expanding cylinder exceeds the total jet diameter does force completely transition to the inverse square law. Don't forget that the jets are conical and up to 14 billion lightyears long, so the width is significant.
 
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  • #14
mfb said:
It is a tiny fraction of the mass of the galaxy, and does not include dark matter.It does not. That's the point of "rest mass" (usually just called mass). It increases the energy, but not beyond the energy present before.
No. Mass increases with relative velocity. Relativistic velocity mass is significant. How is that incorrect? Jet velocities can exceed 0.999c and Lorentz factor of 40. If a modest 5% of the galactic mass were accelerated to 0.999c, the jets would outweigh the remaining galaxy.

What I am looking for is the evidence one way or the other.
 
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  • #15
["tiny fraction"] Who has measured the accumulated mass of Quasar jets? Without measurements, where do we get any scale? (I don't see how human intuition can be relevant to start.)

["It does not"] Agreed. Dark matter has no charge, so it is not going be ejected by electromagnetic effects in the accretion disks. However, can we already be certain that dark matter has no self-interaction at extreme conditions near a spinning black hole?

["energy present before"] How much energy is available when all the hydrogen falls in from intergalactic-cluster distances? If the black hole and accretion disc has formed before the vast majority of the hydrogen arrives, how are we certain that the jets will not outweight the galaxy in the end?

Would an expert on Quasar/Blazer jet mass please leave some links?
 
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  • #16
patellar-myotatic said:
Mass increases with relative velocity.
Not with the meaning of "mass" that has been in use in the last ~80 years. No one uses the concept of a relativistic mass any more, apart from old textbooks and bad pop-science descriptions. "Mass" is always "rest mass".
patellar-myotatic said:
Who has measured the accumulated mass of Quasar jets? Without measurements, where do we get any scale?
Baryonic matter is a small fraction of the total mass of galaxies. The central black hole is very small compared to the baryonic matter. And the jet mass (and also its energy) finally is small compared to the black hole mass. It has to be, everything else would violate conservation of energy.

I don't see dedicated mass estimates, probably because no one cares - it is obvious to everyone writing publications about it that the mass is tiny.
patellar-myotatic said:
However, can we already be certain that dark matter has no self-interaction at extreme conditions near a spinning black hole?
Why would the distance to a black hole matter for a local interaction?
patellar-myotatic said:
How much energy is available when all the hydrogen falls in from intergalactic-cluster distances?
At most its mass multiplied by the speed of light squared. Most of that ends up in the black hole, however.

Where is this going to? If you want to suggest jets would have some relevance on galactic rotation curves, please provide a peer-reviewed reference for that. Otherwise we cannot discuss it.
 

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