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  4. How gravity works in spiral galaxy?
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How gravity works in spiral galaxy?

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Offline Dave Lev (OP)

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Re: How gravity works in spiral galaxy?
« Reply #720 on: 14/09/2019 06:43:46 »
Quote from: Kryptid on 12/09/2019 21:45:18
Quote
3. "A jet in the opposite direction is not seen,". If the "jet appears weak" is about outflow, than why the "A jet in the opposite direction" could not represents the inflow?
If it is inflow - than it is stated clearly - "is not seen".
Can you please explain what is the meaning in English for "is not seen"
Outflow, obviously, since inflow isn't a jet.
Quote from: Kryptid on 12/09/2019 21:45:18
I already corrected you on this. Here's a hint: inflows aren't jets.
Ok
So, do you fully agree that there is no observation for inflow jet?.
http://www.sci-news.com/astronomy/science-chandra-jet-supermassive-black-hole-01564.html
"Jets of high-energy particles are found throughout the Universe, on large and small scales. They are produced by young stars and by black holes a thousand times larger than the Milky Way’s black hole."
So, all the jet that we see in any SMBH is always outflow JET.
We have never ever observed any inflow jet.
However, you still want to believe that somehow we should observe inflow.
If that is correct, why you couldn't say it long time before that you agree that we have never ever found an inflow jet, but you believe that just an inflow is feasible.
So, can you please explain how could it be that all the outflows are coming in jet forms, while the inflows must be just an inflow without jet?
Why there is no clear observation for inflow jet?
If an object will fall into the accretion disc or the SMBH, why it can't create some sort of a jet stream as it falls in?
In any case, I still claim that NASA didn't see any sort of inflow.
Not with a jet and not without a jet.
You claim the opposite.
So let's look again on the following statement:
Quote
The study shows the spin axis of Sgr A* is pointing in one direction, parallel to the rotation axis of the Milky Way, which indicates to astronomers that gas and dust have migrated steadily into Sgr A* over the past 10 billion years.
Your explanation was:
Quote from: Kryptid on 12/09/2019 21:45:18
The study was based on the observational data. The conclusion that matter has been moving inwards for 10 billion years is obviously a result of their analysis of the data. That seems painfully obvious.
What is the meaning of "Their" in the following: "their analysis of the data"?
Do you mean NASA analysis?
If so, I totally disagree.
Who set that Study? Do you see any involvement in the Study by NASA?
Quote from: Kryptid on 12/09/2019 06:22:46
Where do you get that it was a "different study"? Mark Morris is explicitly mentioned as a co-author of the study that the news report is about (with Zhiyuan Li being another co-author). There is another news report by Scientific American that says the same thing: https://www.scientificamerican.com/article/milky-way-black-hole-jet/ And another: https://chandra.harvard.edu/blog/node/467 And another: http://www.sci-news.com/astronomy/science-chandra-jet-supermassive-black-hole-01564.html
In all of those articles which you have offered, you can't find even a single word about the involvement of NASA team in that "Study".
Quote from: Kryptid on 12/09/2019 21:45:18
The study was based on the observational data
This is an error.
In that study, they are using NASA observation to find "the spin axis of Sgr A* is pointing in one direction, parallel to the rotation axis of the Milky Way"
So, they don't extract any inflow (Jet or none jet) from NASA data observation, but the observed outflow jet (which had been discovered by NASA), had been used to show the direction of that "spin axis of Sgr A*"
Why do you insist to mislead yourself and still hope that NASA observation data itself is used to show the inflow?
As it is stated that - "the spin axis of Sgr A* is pointing in one direction, parallel to the rotation axis of the Milky Way", it proves that in that "study" they have used the verified "spin axis pointing direction" and not the observation data itself.
Therefore, it is clear to me that in this "study" they didn't try to find any sort of inflow directly from NASA observed data.
Hence, in that "Study" they didn't try to set any sort of manipulation in the data itself in order to prove any sort of inflow.
However, in that article from arxiv, they have clearly stated that they have used NASA data observation to find inflow.
Therefore, this is a clear manipulation in my point of view.
In any case, it is quite clear to me that you will continue to see it differently.
You wish to show that in NASA observation data there is a prove for inflow - and I fully disagree with that.
Quote from: Kryptid on 12/09/2019 21:45:18
Super-massive black holes can't produce matter.
This is a wrong assumption of the science community.
They just disagree with what they see.
Based on their theory- the SMBH must eat matter from outside.
So, they ignore all the clear observations (from any sort of detector) and try to show that somehow something must fall in.
Do you really believe that we have the power to tell our SMBH if it must eat something or not?
As NASA claims clearly and loudly that they only see outflow jets from any SMBH that they have observed, why is it so difficult for our science community to accept this message as is.
Why can't they accept this clear observation by NASA?
Why can't they go back to the design table and restart their theory?
This is what any design engineer will do once he discovers a contradiction between his theory and the observed data.
Therefore, we live in a world with magnificent breakthrough discoveries and development in electronics and computing.
Each one of us carry a modern I-phone based on the Engineering approach that we must accept the observed data as is and change our theory accordingly.
However, in Astronomy - they don't agree with NASA observed data as is.
Our ASTRONOMERS at arxiv insist to manipulate NASA observation data in order to find a fit to their wishful thinking of INFLOW (any sort of inflow is good for them).
Why is it?
Don't you agree that it is much more logical to update your theory instead of the manipulation in NASA observation data?

In any case.
I really don't want to upset you.
I do appreciate your great support!!!
Let's agree that we disagree on this "inflow" and go on to the next issue.


« Last Edit: 14/09/2019 09:53:43 by Dave Lev »
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Online Kryptid

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Re: How gravity works in spiral galaxy?
« Reply #721 on: 14/09/2019 14:59:34 »
Quote from: Dave Lev on 14/09/2019 06:43:46
Ok
So, do you fully agree that there is no observation for inflow jet?.

Yes, because inflows aren't jets.

Quote from: Dave Lev on 14/09/2019 06:43:46
So, can you please explain how could it be that all the outflows are coming in jet forms, while the inflows must be just an inflow without jet?

I never said that all outflows are in the form of jets. The outflow at the poles of the black hole obviously are, though. There is no reason that an inflow should be a jet.

Quote from: Dave Lev on 14/09/2019 06:43:46
Why there is no clear observation for inflow jet?

Because inflows aren't jets. But I am also confused. You were saying earlier that there was inflow in the past, which means that you agreed that inflow can happen. Are you changing your mind all of a sudden?

Quote from: Dave Lev on 14/09/2019 06:43:46
f an object will fall into the accretion disc or the SMBH, why it can't create some sort of a jet stream as it falls in?

Because that's not what a jet is. That's just a falling gas cloud.

Quote from: Dave Lev on 14/09/2019 06:43:46
What is the meaning of "Their" in the following: "their analysis of the data"?
Do you mean NASA analysis?
If so, I totally disagree.
Who set that Study? Do you see any involvement in the Study by NASA?

Obviously, I'm talking about Zhiyuan Li, Mark Morris and whoever else worked on that study. As long as NASA supplied the data, that's the only involvement on their part that was needed.

Quote from: Dave Lev on 14/09/2019 06:43:46
In all of those articles which you have offered, you can't find even a single word about the involvement of NASA team in that "Study".

They were obviously involved in obtaining the data.

Quote from: Dave Lev on 14/09/2019 06:43:46
This is an error.
In that study, they are using NASA observation to find "the spin axis of Sgr A* is pointing in one direction, parallel to the rotation axis of the Milky Way"
So, they don't extract any inflow (Jet or none jet) from NASA data observation, but the observed outflow jet (which had been discovered by NASA), had been used to show the direction of that "spin axis of Sgr A*"
Why do you insist to mislead yourself and still hope that NASA observation data itself is used to show the inflow?

Because they explicitly said so when they said:

Quote
The study shows the spin axis of Sgr A* is pointing in one direction, parallel to the rotation axis of the Milky Way, which indicates to astronomers that gas and dust have migrated steadily into Sgr A* over the past 10 billion years.

Quote from: Dave Lev on 14/09/2019 06:43:46
As it is stated that - "the spin axis of Sgr A* is pointing in one direction, parallel to the rotation axis of the Milky Way", it proves that in that "study" they have used the verified "spin axis pointing direction" and not the observation data itself.

The observational data is what they used to obtain the spin axis. Otherwise, why bother mentioning Chandra at all?

Quote from: Dave Lev on 14/09/2019 06:43:46
Therefore, it is clear to me that in this "study" they didn't try to find any sort of inflow directly from NASA observed data.

Inflow can't be observed directly. It must always be inferred from data. This would be true for many forms out outflow as well.

Quote from: Dave Lev on 14/09/2019 06:43:46
Hence, in that "Study" they didn't try to set any sort of manipulation in the data itself in order to prove any sort of inflow.

Once again, studies like this never "prove" anything...

Quote from: Dave Lev on 14/09/2019 06:43:46
You wish to show that in NASA observation data there is a prove for inflow - and I fully disagree with that.

No, no I don't. Quit using the word "prove".

Quote from: Dave Lev on 14/09/2019 06:43:46
This is a wrong assumption of the science community.

It's not an assumption. It's a consequence of the laws of physics. Things cannot get out of an event horizon.

Quote from: Dave Lev on 14/09/2019 06:43:46
They just disagree with what they see.

We have never observed a black hole creating matter.

Quote from: Dave Lev on 14/09/2019 06:43:46
Based on their theory- the SMBH must eat matter from outside.
So, they ignore all the clear observations (from any sort of detector) and try to show that somehow something must fall in.

They have observed things falling in (as pointed out numerous times in the past).

Quote from: Dave Lev on 14/09/2019 06:43:46
Do you really believe that we have the power to tell our SMBH if it must eat something or not?

They aren't "telling" it anything.

Quote from: Dave Lev on 14/09/2019 06:43:46
As NASA claims clearly and loudly that they only see outflow jets from any SMBH that they have observed, why is it so difficult for our science community to accept this message as is.

NASA never said that they have only ever observed outflow.

Quote from: Dave Lev on 14/09/2019 06:43:46
Why can't they accept this clear observation by NASA?

Because it isn't what NASA claims.

Quote from: Dave Lev on 14/09/2019 06:43:46
Why can't they go back to the design table and restart their theory?

Because no compelling evidence against the theory has yet to surface.

Quote from: Dave Lev on 14/09/2019 06:43:46
This is what any design engineer will do once he discovers a contradiction between his theory and the observed data.

There is no contradiction.

Quote from: Dave Lev on 14/09/2019 06:43:46
However, in Astronomy - they don't agree with NASA observed data as is.

They obviously do, since they explicitly used that data to come to their conclusions.

Quote from: Dave Lev on 14/09/2019 06:43:46
Our ASTRONOMERS at arxiv insist to manipulate NASA observation data in order to find a fit to their wishful thinking of INFLOW (any sort of inflow is good for them).
Why is it?
Don't you agree that it is much more logical to update your theory instead of the manipulation in NASA observation data?

You have yet to demonstrate that there was any such manipulation.
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Re: How gravity works in spiral galaxy?
« Reply #722 on: 15/09/2019 05:14:08 »
Quote from: Dave Lev
Do you really believe that we have the power to tell our SMBH if it must eat something or not?

A study released this past week shows some bubbles of hot gas around the Milky Way's SMBH.
- One possible interpretation of this observation is that the SMBH had a feeding frenzy a couple of million years ago.
- This hot gas would tend to discourage more gas from flowing into the SMBH
- But it won't stop stars orbiting the SMBH

See: https://news.northwestern.edu/stories/2019/09/milky-way/

In future, we can expect far more data, with much higher resolution, as the MeerKAT pathfinder telescope gets expanded into the Square Kilometer Array radio telescope.
See: https://en.wikipedia.org/wiki/MeerKAT

We are not telling the SMBH when to eat, but we are trying to see when it had breakfast (and what it ate for breakfast)...
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Offline Dave Lev (OP)

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Re: How gravity works in spiral galaxy?
« Reply #723 on: 15/09/2019 20:29:48 »
Quote from: Kryptid on 14/09/2019 14:59:34
The outflow at the poles of the black hole obviously are, though. There is no reason that an inflow should be a jet.
Dear Kryptid
There is no outflow from the pole of the black hole.
This is a severe mistake.
The outflow is from the accretion disc itself.

Please look again at the Wind structure outflow from the accretion disc at the page before the last one:
http://phsites.technion.ac.il/talks/agn2017/Reeves-J.pdf
So, the matter is first ejected outwards from the accretion disc and at the plane of the accretion disc.
In the following article it is stated that it is due to magnetic field:
 https://www.scientificamerican.com/article/milky-way-black-hole-jet/
"Jets arise because the black hole is spinning. As matter falls into the black hole, the matter’s magnetic field gets twisted and amplified by the black hole’s spin, and this pumped-up magnetic field launches material outward in the form of jets."
Therefore, the outflow from the SMBH is always from the accretion disc due to magnetic field.
However, due to the magnetic field lines, the matter is lifted upwards.
Again - we can see it in the presentation which I have offered.

So, let me ask you if you agree with the following:
1.The magnetic field launches material outward from the accretion disc and set the first stage of outflow?
2. The same magnetic field also Pushes this outflow in the direction of upwards/downwards with regards to the accretion disc plane?
3. As it boosted outwards (at almost 0.8c) due to the magnetic field lines it set the molecular jet stream that we see above and below the galactic disc. (this jet stream move directly above the pole)?
4. So, the jet stream outflow that we see above and below the accretion disc plane is a direct outcome from the impact of the magnetic field on the matter in the accretion disc?

If you agree with all the above;
I really can't understand why you constantly refuse to accept the following direct outcome:
This magnetic field is so strong that it can pull matter (including particles, atoms, molecular) from the accretion disc, than band them outwards and shoot them at a speed of 0.8 directly upwards above (or below) the pole of the SMBH.
If so,
1. How any sort of matter can fall into the accretion disc? Why the same mighty magnetic field that sets the outflow jets can't push outwards any matter that just think to fall into the accretion disc?
2. Why the same magnetic field can't pull particles from the event horizon of the SMBH?
Once you agree with that we have solved the enigma of the whole Universe.

« Last Edit: 15/09/2019 20:39:39 by Dave Lev »
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Offline evan_au

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Re: How gravity works in spiral galaxy?
« Reply #724 on: 15/09/2019 22:47:06 »
Quote from: Dave Lev
Please look again at the Wind structure outflow from the accretion disc at the page before the last one:
http://phsites.technion.ac.il/talks/agn2017/Reeves-J.pdf
So, the matter is first ejected outwards from the accretion disc and at the plane of the accretion disc.
In the following article it is stated that it is due to magnetic field:
 https://www.scientificamerican.com/article/milky-way-black-hole-jet/
"Jets arise because the black hole is spinning. As matter falls into the black hole, the matter’s magnetic field gets twisted and amplified by the black hole’s spin, and this pumped-up magnetic field launches material outward in the form of jets."
Therefore, the outflow from the SMBH is always from the accretion disc due to magnetic field.
However, due to the magnetic field lines, the matter is lifted upwards.
Again - we can see it in the presentation which I have offered.

So, let me ask you if you agree with the following:
1.The magnetic field launches material outward from the accretion disc and set the first stage of outflow?
2. The same magnetic field also Pushes this outflow in the direction of upwards/downwards with regards to the accretion disc plane?
3. As it boosted outwards (at almost 0.8c) due to the magnetic field lines it set the molecular jet stream that we see above and below the galactic disc. (this jet stream move directly above the pole)?
4. So, the jet stream outflow that we see above and below the accretion disc plane is a direct outcome from the impact of the magnetic field on the matter in the accretion disc?
Fantastic description! Bravo!
- You have just described the operation of an accretion disk, its magnetic fields and generation of polar jets, as understood by current theories.
- It's a pity that you didn't post this 15 pages ago...

Now given that agreement, there is no need for the rest of your post, which presumes that matter can be extracted from beneath the event horizon of a black hole using magnetic fields.
- According to current theories, this can't be done
- According to current theories, the only thing that can come out of a SMBH event horizon is a tiny wisp of Hawking radiation, which is immeasurably small, even without the energetic maelstrom which is the nearby accretion disk.
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Re: How gravity works in spiral galaxy?
« Reply #725 on: 15/09/2019 23:19:14 »
Quote from: Dave Lev on 15/09/2019 20:29:48
Dear Kryptid
There is no outflow from the pole of the black hole.
This is a severe mistake.
The outflow is from the accretion disc itself.

Please look again at the Wind structure outflow from the accretion disc at the page before the last one:
http://phsites.technion.ac.il/talks/agn2017/Reeves-J.pdf

That particular website is about “disk winds”. It’s true that they originate from the accretion disk, but they are a different phenomenon from the polar jets. The word “jet” isn’t even in that document.

Quote from: Dave Lev on 15/09/2019 20:29:48
In the following article it is stated that it is due to magnetic field:
 https://www.scientificamerican.com/article/milky-way-black-hole-jet/
"Jets arise because the black hole is spinning. As matter falls into the black hole, the matter’s magnetic field gets twisted and amplified by the black hole’s spin, and this pumped-up magnetic field launches material outward in the form of jets."
Therefore, the outflow from the SMBH is always from the accretion disc due to magnetic field.
However, due to the magnetic field lines, the matter is lifted upwards.
Again - we can see it in the presentation which I have offered.

Yes, all of that is true, but it isn’t related to disk winds. The polar jets are a different phenomenon. These are the jets from the poles that I am talking about: http://astronomy.swin.edu.au/cosmos/G/Galactic+Jets There is one on each side of the galaxy. The jets don’t literally come from the poles of the black hole, the accretion flow is just lifted along those particular axes.

Quote from: Dave Lev on 15/09/2019 20:29:48
So, let me ask you if you agree with the following:
1.The magnetic field launches material outward from the accretion disc and set the first stage of outflow?
2. The same magnetic field also Pushes this outflow in the direction of upwards/downwards with regards to the accretion disc plane?

For disk winds, yes.


Quote from: Dave Lev on 15/09/2019 20:29:48
3. As it boosted outwards (at almost 0.8c) due to the magnetic field lines it set the molecular jet stream that we see above and below the galactic disc. (this jet stream move directly above the pole)?

No, the polar jets are a different phenomenon (even though they also originate from the accretion disk and are propelled by magnetic fields).


Quote from: Dave Lev on 15/09/2019 20:29:48
4. So, the jet stream outflow that we see above and below the accretion disc plane is a direct outcome from the impact of the magnetic field on the matter in the accretion disc?

Yes.

Quote from: Dave Lev on 15/09/2019 20:29:48
1. How any sort of matter can fall into the accretion disc? Why the same mighty magnetic field that sets the outflow jets can't push outwards any matter that just think to fall into the accretion disc?

Because magnetic fields neither attract nor repel charged particles. The way that the particles interact with the field is strongly dependent upon their path relative to the field lines. Those moving up or down can continue to move up or down, but those moving directly at right angles to the field lines will only spin around the field lines without moving up or down significantly. This spin will cause the particle to lose energy, weakening the effect of the magnetic field on it and allowing it to fall further towards the black hole.

Quote from: Dave Lev on 15/09/2019 20:29:48
2. Why the same magnetic field can't pull particles from the event horizon of the SMBH?

Because magnetic fields can’t move things into the past. This has been explained to you many times before.

Quote
Once you agree with that we have solved the enigma of the whole Universe.

No we won’t, because your model violates conservation of mass/energy (a black hole cannot send mass/energy out in the Universe without losing mass/energy itself).
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Re: How gravity works in spiral galaxy?
« Reply #726 on: 16/09/2019 00:52:54 »
Quote from: Kryptid on 15/09/2019 23:19:14
The jets don’t literally come from the poles of the black hole, the accretion flow is just lifted along those particular axes.
The jets are going to be aligned with the axis of rotation of the accretion disk, not the axis of the black hole itself.  Give well over 10 billion years of accretion of material that's got pretty reasonable reason to have the same rotation as the galaxy in general, the two axes are likely to be well aligned if the current disk was formed by matter with the same rotation axis as the average.  This is not always the case, as a cloud can come in from just about anywhere.

The one galaxy had 7 disks, all misaligned from each other.  Makes you wonder if only the innermost one has a strong enough magnetic field to produce a clean jet, or if there are multiple jets, or if the other rings just interfere and disrupt any jet that would otherwise have formed.
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Re: How gravity works in spiral galaxy?
« Reply #727 on: 16/09/2019 01:20:19 »
Quote from: Halc on 16/09/2019 00:52:54
The jets are going to be aligned with the axis of rotation of the accretion disk, not the axis of the black hole itself.

Yes, that's true. I was making a simplified assumption.
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Offline Dave Lev (OP)

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Re: How gravity works in spiral galaxy?
« Reply #728 on: 16/09/2019 15:57:53 »
Quote from: Kryptid on 15/09/2019 23:19:14
The polar jets are a different phenomenon. These are the jets from the poles that I am talking about: http://astronomy.swin.edu.au/cosmos/G/Galactic+Jets There is one on each side of the galaxy. The jets don’t literally come from the poles of the black hole, the accretion flow is just lifted along those particular axes.
Thanks Kryptid
Do appreciate this great article.
It is stated:
"Another question troubling astronomers is what exactly are these jets made of? The modern consensus is that the main constituents are electrons and their anti-particle equivalent, positrons. These are thought to be produced by ‘pair-production’ close to the event horizon of the central black hole, and squirted out at almost light speed by the action of the combined magnetic fields."
So, our scientists estimates that there is a possibility for ‘pair-production’ close to the event horizon of the central black hole, and squirted out at almost light speed by the action of the combined magnetic fields.
That meets my expectations form the mighty magnetic fields.
So, why our scientists can justify those pair-production near the event of horizon that are squirted out by magnetic force, while it is forbidden for me to use the same identical idea?
« Last Edit: 16/09/2019 17:04:19 by Dave Lev »
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Re: How gravity works in spiral galaxy?
« Reply #729 on: 16/09/2019 18:16:59 »
Quote from: Dave Lev on 16/09/2019 15:57:53
So, why our scientists can justify those pair-production near the event of horizon that are squirted out by magnetic force, while it is forbidden for me to use the same identical idea?

Your idea wasn't identical. You were proposing that they come from within the event horizon.
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Re: How gravity works in spiral galaxy?
« Reply #730 on: 16/09/2019 19:37:47 »
The pair production they see is near (about a million km for something the mass of Sgr-A) accreting black holes due to interaction of high-energy photons (about 1.022 MeV) which is the energy required for pair production like that.  Not sure how that sources material for the jets since the positrons typically find another electron somewhere in the accretion disk and annihilate it, for a net zero gain of charged particles.
Some of this info taken from the abstract of https://iopscience.iop.org/article/10.3847/1538-4357/aac090
where they define 'near' and the actual mechanism (high energy photon interaction from active accretion radiation)
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Offline Dave Lev (OP)

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Re: How gravity works in spiral galaxy?
« Reply #731 on: 16/09/2019 20:49:43 »
Quote from: Kryptid on 16/09/2019 18:16:59
Your idea wasn't identical. You were proposing that they come from within the event horizon.
Well, I really don't care about the distance between those new created pair production to the event horizon.
As long as they are squirted out at almost light speed by the action of the combined magnetic fields from the SMBH into the accretion disc - that is perfectly OK with me.
Quote from: Halc on 16/09/2019 19:37:47
Not sure how that sources material for the jets since the positrons typically find another electron somewhere in the accretion disk and annihilate it, for a net zero gain of charged particles
It seems to me that our knowledge about the functionality of the accretion disc is quite poor.
In the accretion disc new arrival created partials which had been squirted out from the SMBH are converted into real Atoms and molecular.
Therefore, at the innermost accretion ring, we should see mainly those kind of new born particles.
However, as the particles are drifted outwards in the accretion disc, they are converted into atoms and molecular.
Finally, they are ejected outwards from the accretion disc and lifted upwards (or downwards) by the mighty magnetic fields and set the molecular jet stream.
There is an excellent reason for why the galaxy needs to create that jet stream.
Not all the particles have been converted into real atoms and molecular at the moment that they are ejected from the accretion disc.
Therefore, in the outflow from the accretion disc we should find particles, broken atoms, atoms and molecular.
If those  particles will be part of a new star it might create a very negative impact.
Somehow, those immature particles must be pushed away.
Therefore, the accretion outflow is boosted upwards into a molecular jet stream by the magnetic field.
The relatively heavy atoms and molecular are falling back to the galactic disc plane and are gathered into gas cloud in order to start the new star forming activity, while the immature particles are pushed away from the galaxy.
So, the molecular jet stream set the cleaning activity and push away the immature particles from the matter which should be used as the building blocks for any new star.

« Last Edit: 16/09/2019 20:53:19 by Dave Lev »
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Re: How gravity works in spiral galaxy?
« Reply #732 on: 16/09/2019 22:49:29 »
Quote from: Dave Lev on 16/09/2019 20:49:43
Well, I really don't care about the distance between those new created pair production to the event horizon.
As long as they are squirted out at almost light speed by the action of the combined magnetic fields from the SMBH into the accretion disc - that is perfectly OK with me.

The pair production happens in the accretion disk near the event horizon, where the temperatures are very, very high. Another example of such pair production is in "pair-instability supernova": https://en.wikipedia.org/wiki/Pair-instability_supernova

Since the temperature of the material itself is what drives this, the energy and mass of the accretion disk is reduced by it when the pairs are blasted off into the jets. So you are still left with the conundrum of where the matter in the accretion disk comes from, since you don't allow it to come in from outside nor can it come out of the black hole because of the event horizon.
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Offline Dave Lev (OP)

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Re: How gravity works in spiral galaxy?
« Reply #733 on: 17/09/2019 07:58:24 »
Quote from: Kryptid on 16/09/2019 22:49:29
The pair production happens in the accretion disk near the event horizon, where the temperatures are very, very high
Dear Kryptid
Quote from: Dave Lev on 16/09/2019 15:57:53
The modern consensus is that the main constituents are electrons and their anti-particle equivalent, positrons. These are thought to be produced by ‘pair-production’ close to the event horizon of the central black hole, and squirted out at almost light speed by the action of the combined magnetic fields."
Our scientists specifically claim that the ‘pair-production’ are produced close to the event horizon of the central black hole.
Therefore, it is clear that the ‘pair-production’ have been produced outside the accretion disc.
Hence the pair- production activity itself has no effect on the energy and mass in the accretion disk.
However, as the pair- production are squirted out at almost light speed by the action of the combined magnetic fields and drift into the innermost ring of the accretion disc - the mass of the accretion disc is increasing.
In the accertion disc, those particales are transformed into real Atoms and Molecular. The main energy for that activity is coming from the same magnetic field. Therefore, in total the mass of the accretion disc is increasing due to the new arrival of the  pair- production and due to the transformation activity.
You claim:
Quote from: Kryptid on 16/09/2019 22:49:29
Since the temperature of the material itself is what drives this, the energy and mass of the accretion disk is reduced by it when the pairs are blasted off into the jets
The pairs are blasted off into the jets by the power of the magnetic fields.
Hence, the energy and mass in the accretion disc is quite stable in the long run due to the balance between the inflow into the accretion disc of the new born pair- production  from the event horizon (or close to it) and their transformation activity into new atoms and molecular with regards to the total jet outflow from the accretion disc.
Don't you see that the game is over?
You have offered solid evidence to that theory.
Fron now on we must call it - Excretion disc.
Why don't we share our efforts in bringing the breakthrough information to the science community and mankind?
We need to get a reward for our discovery!!!
« Last Edit: 17/09/2019 08:08:24 by Dave Lev »
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Re: How gravity works in spiral galaxy?
« Reply #734 on: 17/09/2019 14:11:55 »
Quote from: Dave Lev on 17/09/2019 07:58:24
Therefore, it is clear that the ‘pair-production’ have been produced outside the accretion disc.

Not at all. Pair production is modeled as happening inside the accretion disk. There are other sources that state this:
https://iopscience.iop.org/article/10.1088/0004-637X/735/1/9/meta

Quote
Here, we use a self-consistent dynamical and radiative model to investigate pair production by γγ collisions in weakly radiative accretion flows around a black hole of mass M and accretion rate M.

http://cxc.harvard.edu/cdo/accr10/pres/moscibrodzka_monika.pdf:

Quote
For first time we compute non-equilibrium electron-positron pair production rates by γγ from turbulent accretion disk around spinning black hole


https://www.sciencedirect.com/science/article/pii/S0273117797000458:

Quote
The high pair creation rate during this state is indicated by the presence of a broad e−e+ annihilation line-like feature and needs the presence of a high temperature radiation field. We put forward a scenario in which the observed spectrum originates from the inner region of an accretion disk around a rapidly rotating black hole.
Quote from: Dave Lev on 17/09/2019 07:58:24
Hence the pair- production activity itself has no effect on the energy and mass in the accretion disk.

Yes it does, since the energy of the accretion disk is what allows them to be formed in the first place.

Quote from: Dave Lev on 17/09/2019 07:58:24
the mass of the accretion disc is increasing.

So where do you claim that this extra mass comes from? If the pairs aren't produced by the accretion disk, what are they produced by? Where does the energy necessary to create those pairs come from? Do you recognize that whatever source you choose must lose energy in the process of creating those pairs?

Quote from: Dave Lev on 17/09/2019 07:58:24
Don't you see that the game is over?

It was over as soon as you made the first post in this thread, because your model was wrong since the first post.

Quote from: Dave Lev on 17/09/2019 07:58:24
You have offered solid evidence to that theory.

I have offered nothing that shows the pairs are produced anywhere outside of the plasma around the black hole. Energy is required to produce particle pairs. That energy has to come from somewhere.

Quote from: Dave Lev on 17/09/2019 07:58:24
Fron now on we must call it - Excretion disc.

Non-sequitur.

Quote from: Dave Lev on 17/09/2019 07:58:24
Why don't we share our efforts in bringing the breakthrough information to the science community and mankind?
We need to get a reward for our discovery!!!

You haven't made any discoveries.
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Re: How gravity works in spiral galaxy?
« Reply #735 on: 17/09/2019 17:33:49 »
Quote from: Kryptid on 17/09/2019 14:11:55
Quote
Therefore, it is clear that the ‘pair-production’ have been produced outside the accretion disc.
Not at all. Pair production is modeled as happening inside the accretion disk. There are other sources that state this:
https://iopscience.iop.org/article/10.1088/0004-637X/735/1/9/meta
In this article it is stated clearly that pair production is concentrated close to the event horizon, but not in the accretion disc:
"Electron-positron pairs may be produced near accreting black holes by a variety of physical processes"
"We have studied electron–positron pair production in black hole magnetospheres by γγ collisions."
"The pair production rates are calculated nearly ab initio within 40GM/c2 of the event horizon, using Monte Carlo methods."
"The main results of this work are the fitting formulae for the rate and spatial distribution of pair production in terms of m8 and $\dot{m}$ (Equation (26)) and in terms of m8, LX, and α (Equation (30)). These indicate that γγ pair production is concentrated close to the event horizon, and is sensitive to model parameters such as $\dot{m}$."
So, where do you see that Pair production is happening inside the accretion disk?
Quote from: Kryptid on 17/09/2019 14:11:55
http://cxc.harvard.edu/cdo/accr10/pres/moscibrodzka_monika.pdf:
"For first time we compute non-equilibrium electron-positron pair production rates by γγ from turbulent accretion disk around spinning black hole"
In this model they discuss about "turbulent accretion disk around spinning black hole".
I don't think that they aim for the accretion disc.
Please look at the following article:
https://iopscience.iop.org/article/10.1088/0004-637X/735/1/9/meta
It is stated:
Our pair production rate simulations are based on a GRMHD time-dependent model of a magnetized disk around a spinning black hole.
Therefore, the real meaning of "turbulent accretion disk around spinning black hole" is "magnetized disk around a spinning black hole."

Quote from: Kryptid on 17/09/2019 14:11:55
https://www.sciencedirect.com/science/article/pii/S0273117797000458:

Quote
The high pair creation rate during this state is indicated by the presence of a broad e−e+ annihilation line-like feature and needs the presence of a high temperature radiation field. We put forward a scenario in which the observed spectrum originates from the inner region of an accretion disk around a rapidly rotating black hole.
In this article they don't discuss about the location of the pair production. They just speak about the the observed spectrum originates from the inner region of an accretion disk around a rapidly rotating black hole."
This is very interesting.
Actually as the pair production is drifted outwards, it must meet the inner region of the accretion disc.
Therefore, it is very interesting to understand what kind of spectrum they have observed and what can we learn from that.
Quote from: Kryptid on 17/09/2019 14:11:55
Quote
Hence the pair- production activity itself has no effect on the energy and mass in the accretion disk.
Yes it does, since the energy of the accretion disk is what allows them to be formed in the first place.

Sorry, in most of the articles it is stated that the pair - production activity is NEAR the event horizon (and not in the accretion disc itself)

« Last Edit: 17/09/2019 17:50:57 by Dave Lev »
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Re: How gravity works in spiral galaxy?
« Reply #736 on: 17/09/2019 21:41:07 »
Quote from: Dave Lev on 17/09/2019 17:33:49
So, where do you see that Pair production is happening inside the accretion disk?

Here:

Quote
For first time we compute non-equilibrium electron-positron pair production rates by γγ from turbulent accretion disk around spinning black hole.

and here:

Quote
We put forward a scenario in which the observed spectrum originates from the inner region of an accretion disk around a rapidly rotating black hole.

Quote from: Dave Lev on 17/09/2019 17:33:49
I don't think that they aim for the accretion disc.

What do you mean when you say "aim" for the accretion disk?

Quote from: Dave Lev on 17/09/2019 17:33:49
Therefore, the real meaning of "turbulent accretion disk around spinning black hole" is "magnetized disk around a spinning black hole."

Which, in other words, is the accretion disk.

Quote from: Dave Lev on 17/09/2019 17:33:49
Sorry, in most of the articles it is stated that the pair - production activity is NEAR the event horizon (and not in the accretion disc itself)

You realize that "near the event horizon" and "in the accretion disk" are not mutually-exclusive locations, don't you?
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Re: How gravity works in spiral galaxy?
« Reply #737 on: 17/09/2019 22:41:10 »
Quote from: DaveLev, with original emphasis
In this article it is stated clearly that pair production is concentrated close to the event horizon, but not in the accretion disc:
"Electron-positron pairs may be produced near accreting black holes by a variety of physical processes"
These indicate that γγ pair production is concentrated close to the event horizon
So, where do you see that Pair production is happening inside the accretion disk?
You do realise that as the matter in the accretion disk spirals closer to the black hole, most of it actually spirals right into the event horizon?
So there is no actual gap between the event horizon and the inner edge of the accretion disk?
So every time an article says "near a black hole event horizon", they actually mean that it happens within, or on the edges of, the accretion disk.

Quote from: Dave Lev
Fron now on we must call it - Excretion disc.
According to current computer models, about 90% of the matter in the accretion disk falls into the black hole, and only around 10% goes into the polar jets. So retaining the term "accretion disk" is 900% more accurate than changing it to "excretion disk".
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Re: How gravity works in spiral galaxy?
« Reply #738 on: 18/09/2019 19:56:00 »
Quote from: Kryptid on 17/09/2019 21:41:07
You realize that "near the event horizon" and "in the accretion disk" are not mutually-exclusive locations, don't you?
Quote from: evan_au on 17/09/2019 22:41:10
So every time an article says "near a black hole event horizon", they actually mean that it happens within, or on the edges of, the accretion disk.
Are you both sure about it?
If I recall correctly, you (or Halc) have stated that there is no possibly that the pair-production will take place at the accretion disc, as special conditions are needed for the particles creation. I have got the impression from you that the Pair-production activity must take place even below the event horizon.
Now, suddenly, you claim that the pair-production can be created in the accretion disc, high above the event horizon.
Thanks for that Great news.
If new particles can be created at the accretion disc, than why do I need to find a solution how to squirt out the new particles from the event horizon (or close to it)?
I don't need any more to call the magnetic field for help. Therefore, the following explanation is not needed:
"The modern consensus is that the main constituents are electrons and their anti-particle equivalent, positrons. These are thought to be produced by ‘pair-production’ close to the event horizon of the central black hole, and squirted out at almost light speed by the action of the combined magnetic fields."
Now you agree that new particle are created at the accretion disc. Therefore, the solution is as follow:
New particle are created at the innermost accretion ring.
Due to their ultra high velocity (at the moment of creation), high gravity force and mighty magnetic field those particles are transformed into real atoms as they are drifted outwards.
The requested energy for that transformation is contributed by the gravity force + magnetic energy.
Therefore, the outflow jet from the accretion disc is a direct outcome from that process.
I hope that this explanation meets your expectations.
« Last Edit: 18/09/2019 20:00:04 by Dave Lev »
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Re: How gravity works in spiral galaxy?
« Reply #739 on: 18/09/2019 21:31:01 »
Quote from: Dave Lev on 18/09/2019 19:56:00
The requested energy for that transformation is contributed by the gravity force + magnetic energy.

The only way to get energy out of a gravitational field is by converting gravitational potential energy into kinetic energy. This, in turn, can only be done by lowering a mass into the gravitational field. You, however, are taking a mass and pushing it out and far away from the black hole (in the form of jets). That doesn't give you energy, it requires it instead. So gravity is not a source of energy you can use for this.

Magnetism can indeed transfer energy (electric motors use this principle all the time), but that energy doesn't come from nowhere. The source of that magnetic field must lose energy in the process. If the source of the field is the accretion disk, then the disk must lose energy. If the source of the field is the black hole (in your hypothetical case), then the black hole must lose energy (likely by slowing down its spin). So you still have a system that loses energy and mass over time.
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