Matter in accretion disks VS higgs-boson at CERN

[David Levy]

But we were talking of active black holes with large accretion disks.

 

Sorry for the misunderstanding.

I only focus on accretion disk in spiral galaxy!!!

Edited March 21, 2017 by David Levy

[swansont]

 

Sorry for the misunderstanding.

I only focus on accretion disk in spiral galaxy!!!

 

 

No, you weren't focusing on that. You changed the discussion and just recently brought that up. It would be helpful if you didn't do that.

[David Levy]

With regards to G2 clouds.

 

Please see the following:

https://en.wikipedia.org/wiki/Sagittarius_A*

"The average rate of accretion onto Sgr A* is unusually small for a black hole of its mass^[39] and is only detectable because it is so close to Earth. It was thought that the passage of G2 in 2013 might offer astronomers the chance to learn much more about how material accretes onto supermassive black holes. Several astronomical facilities observed this closest approach, with observations confirmed with Chandra, XMM, EVLA, INTEGRAL, Swift, Fermi and requested at VLT and Keck.^[40]

Simulations of the passage were made before it happened by groups at ESO^[41] and Lawrence Livermore National Laboratory (LLNL).^[42]

As the cloud approached the black hole, Dr. Daryl Haggard said "It's exciting to have something that feels more like an experiment", and hoped that the interaction would produce effects that would provide new information and insights.^[43]

Nothing was observed during and after the closest approach of the G2 cloud the black hole, which was described as a lack of "fireworks" and a "flop".^[44] Astronomers from the UCLA Galactic Center Group published observations obtained on March 19 and 20, 2014, concluding that G2 was still intact (in contrast to predictions for a simple gas cloud hypothesis) and that the cloud was likely to have a central star.^[45]"

If I understand it correctly:

The science estimates that the SMBH must eat a nearby mass/cloud.

However, somehow, our SMBH is not so cooperative with the theories. He just refuses to eat that cloud.

If I remember correctly, there was also the same issue with another cloud (G1?).

So, why our SMBH refuse to eat its food although it is so close to his mouth?

Edited March 21, 2017 by David Levy

[swansont]

 

If I understand it correctly:

The science estimates that the SMBH must eat a nearby mass/cloud.

However, somehow, our SMBH is not so cooperative with the theories. He just refuses to eat that cloud.

If I remember correctly, there was also the same issue with another cloud (G1?).

So, why our SMBH refuse to eat its food although it is so close to his mouth?

 

 

You just got done pointing out that the mass in the accretion disk is currently very small — that of an asteroid, or similar. So how does one conclude that it refuses to "eat" ? The "plate" is pretty much empty. Perhaps it's done eating? As far as G2 goes, there are explanations included in what you quoted (it might not be a simple cloud, but have a star inside) plus what was discussed earlier. A system needs to shed angular momentum to fall into a black hole.

[Strange]

Sorry for the misunderstanding.

I only focus on accretion disk in spiral galaxy!!!

 

 

So what. We were talking of active black holes with large accretion disks. And then you started talking about the mass of matter around an inactive black hole.

So, why our SMBH refuse to eat its food although it is so close to his mouth?

 

The text you quoted explains why. Read it.

[David Levy]

Thanks

In order to explain why the SMBH didn't eat G2 it is stated:

"Professor Andrea Ghez et al. suggested in 2014 that G2 is not a gas cloud but rather a pair of binary stars that had been orbiting the black hole in tandem and merged into an extremely large star.[36][46]".

However, in the explanation of the accretion disk it is stated clearly that it gets new matter from a giant star:

http://www.einstein-online.info/spotlights/accretion

"Another example of a near-miss orbit, this one somewhat more complicated, can be seen in the image below - a binary star system consisting of a giant star, shown on the left, and a compact companion star, on the right:"

So, why now we suddenly claim that those pair of binary stars that had been orbiting the black hole in tandem and merged into an extremely large star couldn't share their mass with the SMBH accretion disk?

It is also stated:

https://en.wikipedia.org/wiki/Sagittarius_A*#Discovery_of_G2_gas_cloud_on_an_accretion_course

"An analysis published on 21 July 2014 based on observations by the ESO’s Very Large Telescope in Chile concluded alternatively that the cloud, rather than being isolated, might be a dense clump within a continuous but thinner stream of matter, and would act as a constant breeze on the disk of matter orbiting the black hole, rather than sudden gusts that would have caused fireworks as they hit, as originally expected. Supporting this hypothesis, G1, a cloud that passed near the black hole 13 years ago, had an orbit almost identical to G2, consistent with both clouds, and a gas tail thought to be trailing G2, all being denser clumps within a large single gas stream.[44]"

As the total mass of the SMBH accretion disk about an asteroid, it is expected see the impact of that breeze on accretion disk.

 

Did we see it?

 

So, after almost 32 Month, do we have any further info about G2 and G1 cloud?

 

Do they still rotate nearby the SMBH? In what kind of rotation shape? At what speed? How long it takes them to set one cycle around the SMBH? Are they drifting inwards or outwards from the SMBH? What is their composition?

Do we see that extremely large star in G2 cloud?

Actually, as we monitor this aria for the last 13 years (or longer), did we ever see any sort of mass which had been eaten by the SMBH?

Did we see any impact on the accretion disk?

If no, how can we explain it?

Edited March 22, 2017 by David Levy

[Strange]

 

However, in the explanation of the accretion disk it is stated clearly that it gets new matter from a giant star:

 

 

That is one possibility, not the only one.

 

 

 

So, why now we suddenly claim that those pair of binary stars that had been orbiting the black hole in tandem and merged into an extremely large star couldn't share their mass with the SMBH accretion disk?

 

The fact that it didn't act as a gas cloud suggest that there is a central star. The size and other details of the star suggest that the star was created at some time by the merger of a binary pair.

 

I would suggest you read the original paper (linked from the paragraph you quoted): http://iopscience.iop.org/article/10.1088/2041-8205/796/1/L8/meta;jsessionid=821E757EFAC5A42AFA4846CDE1CC705B.c2.iopscience.cld.iop.org

 

Note that there was nothing "sudden" about this. A number of astronomers suggested that G2 was a star before the encounter with the black hole (see the references in the above paper).

 

 

 

Do they still rotate nearby the SMBH? In what kind of rotation shape? At what speed? How long it takes them to set one cycle around the SMBH?

 

Again, following the references from the paragraph you posted:

"[G2] appears to have an unusual, 300-year elliptical orbit around the black hole."

http://earthsky.org/space/how-g2-survived-the-black-hole-at-our-milky-ways-heart

[swansont]

 

As the total mass of the SMBH accretion disk about an asteroid, it is expected see the impact of that breeze on accretion disk.

 

 

 

Expected by whom?

[David Levy]

Expected by whom?

 

Lets start by the expectation about G2:

In the following simulation we can see that G2 is moving towards the SMBH.

https://en.wikipedia.org/wiki/Sagittarius_A*#Discovery_of_G2_gas_cloud_on_an_accretion_course

In the following simulation we can see scientist's expectation from this activity:

"Simulations of the passage were made before it happened by groups at ESO^[41] and Lawrence Livermore National Laboratory (LLNL).^[42]"

 

It was stated:

"As the cloud approached the black hole, Dr. Daryl Haggard said "It's exciting to have something that feels more like an experiment", and hoped that the interaction would produce effects that would provide new information and insights.^[43]"

https://en.wikipedia.org/wiki/Sagittarius_A*#/media/File:G2Cloud_eso1151a.jpeg

https://en.wikipedia.org/wiki/Sagittarius_A*#Discovery_of_G2_gas_cloud_on_an_accretion_course

And the outcome was:

"Nothing was observed during and after the closest approach of the cloud to the black hole, which was described as a lack of "fireworks" and a "flop".^[44] Astronomers from the UCLA Galactic Center Group published observations obtained on March 19 and 20, 2014, concluding that G2 was still intact (in contrast to predictions for a simple gas cloud hypothesis) and that the cloud was likely to have a central star.^[45]"

 

It is stated clearly - "(in contrast to predictions for a simple gas cloud hypothesis)", while they were expecting to see fireworks...

So, they were expecting for fireworks, but got nothing.

However, instead of admit that there is a problem with this hypothesis, they came with an idea about a breeze which shouldn't have any effect on the accretion disk.

 

Please don't forget that the plasma in the accretion disk is moving almost at the speed of light.

So even a small amount of mass might have an effect - as in CERN. (Unless the breeze is so neglected that we can forget it.)

In any case - do they claim that this breeze can contribute any real mass to the SMBH?

Do they have any idea about the total mass in this breeze? Just to say breeze wouldn't be considered as a real scientific answer.

In other words, so far I couldn't find any real evidence of mass which goes directly to the SMBH accretion disk.

Not G1, Not G2.

In the following article it is stated:

http://earthsky.org/space/how-g2-survived-the-black-hole-at-our-milky-ways-heart

"G2 was completely unaffected by the black hole. There were no fireworks."

So, If G2 was completely unaffected - than we can forget the idea of mass contribution by breeze...

Edited March 22, 2017 by David Levy

[swansont]

 

Lets start by the expectation about G2:

In the following simulation we can see that G2 is moving towards the SMBH.

https://en.wikipedia.org/wiki/Sagittarius_A*#Discovery_of_G2_gas_cloud_on_an_accretion_course

In the following simulation we can see scientist's expectation from this activity:

"Simulations of the passage were made before it happened by groups at ESO^[41] and Lawrence Livermore National Laboratory (LLNL).^[42]"

 

It was stated:

"As the cloud approached the black hole, Dr. Daryl Haggard said "It's exciting to have something that feels more like an experiment", and hoped that the interaction would produce effects that would provide new information and insights.^[43]"

https://en.wikipedia.org/wiki/Sagittarius_A*#/media/File:G2Cloud_eso1151a.jpeg

https://en.wikipedia.org/wiki/Sagittarius_A*#Discovery_of_G2_gas_cloud_on_an_accretion_course

And the outcome was:

"Nothing was observed during and after the closest approach of the cloud to the black hole, which was described as a lack of "fireworks" and a "flop".^[44] Astronomers from the UCLA Galactic Center Group published observations obtained on March 19 and 20, 2014, concluding that G2 was still intact (in contrast to predictions for a simple gas cloud hypothesis) and that the cloud was likely to have a central star.^[45]"

 

It is stated clearly - "(in contrast to predictions for a simple gas cloud hypothesis)", while they were expecting to see fireworks...

So, they were expecting for fireworks, but got nothing.

However, instead of admit that there is a problem with this hypothesis, they came with an idea about a breeze which shouldn't have any effect on the accretion disk.

 

Please don't forget that the plasma in the accretion disk is moving almost at the speed of light.

So even a small amount of mass might have an effect - as in CERN. (Unless the breeze is so neglected that we can forget it.)

In any case - do they claim that this breeze can contribute any real mass to the SMBH?

Do they have any idea about the total mass in this breeze? Just to say breeze wouldn't be considered as a real scientific answer.

In other words, so far I couldn't find any real evidence of mass which goes directly to the SMBH accretion disk.

Not G1, Not G2.

In the following article it is stated:

http://earthsky.org/space/how-g2-survived-the-black-hole-at-our-milky-ways-heart

"G2 was completely unaffected by the black hole. There were no fireworks."

So, If G2 was completely unaffected - than we can forget the idea of mass contribution by breeze...

 

 

They were expecting to see fireworks if a certain assumption was correct, i.e. that G2 was an isolated gas cloud (not a "breeze" of matter, and no central mass) And I see nothing that indicates that this was because of the small amount of mass in the accretion disk. The reason a "breeze" wouldn't give the "fireworks" is that whatever the infall rate is it wouldn't be varying, so no signal fluctuations would be expected. You are, as per usual, extrapolating what you're reading and drawing invalid conclusions.

 

If we have a small mass in the accretion disk, we would not expect much in the way of collisions as a cloud passed through, and as I pointed out before, the relative speed of the particles is what's important. The phrasing of the wikipedia passage implies they were looking for the cloud to be distorted by the BH and have the sudden introduction of new matter to produce a signal as some of it fell in, rather than any effects from the disk. As it was not distorted and there was no such signal, they conclude that it could be a star or have one inside

 

This story indicates that it's a star

http://etheric.com/new-keck-telescope-observations-g2-cloud/

[David Levy]

Thanks

1. When did we start to monitor the Milky Way SMBH aria including its accretion disk?

2. Did we ever notice in any sort of matter which is moving into the SMBH accretion disk? (In other words - do we have any evidence that the SMBH is really eating mass from outside)?

3. The total mass in the accretion disk is as asteroid. That is clear. As we call it accretion - we mean that the mass in this aria must move inwards to SMBH (Eaten by the SMBH). So, based on our theories, how long it might take the SMBH to eat all of that Asteroid mass in the accrtion disk, assuming that no matter is coming in from outside (and no new matter is creating by the accretion itself)?

Edited March 23, 2017 by David Levy

[Strange]

1. Don't know

 

2 & 3. The accretion disk mainly contains matter from the nearby stars (there may be other sources as well). So it may be in some sort of equilibrium (gas absorbed by the black hole versus new gas from the stars).

 

This has some figures for accretion rate: http://iopscience.iop.org/article/10.1086/312035/fulltext/

 

If you search for accretion rate, you will find several other studies proposing mechanisms to describe what is observed.

[swansont]

 

3. The total mass in the accretion disk is as asteroid. That is clear. As we call it accretion - we mean that the mass in this aria must move inwards to SMBH (Eaten by the SMBH). So, based on our theories, how long it might take the SMBH to eat all of that Asteroid mass in the accrtion disk, assuming that no matter is coming in from outside (and no new matter is creating by the accretion itself)?

 

 

 

You should be able to reason that it will take a very long time to do this, based on what's been discussed. There will always be some mass with too much angular momentum to be captured.

[David Levy]

1. Don't know

 

2 & 3. The accretion disk mainly contains matter from the nearby stars (there may be other sources as well). So it may be in some sort of equilibrium (gas absorbed by the black hole versus new gas from the stars).

 

This has some figures for accretion rate: http://iopscience.iop.org/article/10.1086/312035/fulltext/

 

If you search for accretion rate, you will find several other studies proposing mechanisms to describe what is observed.

 

Thanks

Can you please advice what is the meaning of "is believed to be"?

"The radio source Sagittarius A* at the center of our Galaxy is believed to be a 2.6×10(6) M0 black hole that accretes gas from the winds of nearby stars."

So, do we need to believe that the size of the SMBH is 2.6×10(6) M0, or do we need to believe that there are nearby stars?

Based on my understanding, the total mass of the SMBH had been set by the S2 orbit. So, technically I assume that the radio source has no effect on that mass.

Hence, does it mean that based on the radio source we have to believe that accretion disk gets the requested mass from the nearby stars?

However, why we have to believe?

Do we really see those stars?

What does it mean?

" 2.If the stars in the Galactic center are not randomly distributed around Sgr A* but instead have a large z-coordinate offset, the predicted accretion rate will be reduced. "

If we see those stars, than we should easily know their distributed around Sgr A*.

If we don't see those stars, than what is the difference between speculation and believe in...?

Edited March 24, 2017 by David Levy

[swansont]

In both cases, it's a matter of what's consistent with the evidence. Not all of what goes on in science is direct observation; in many disciplines, it's very little. But when there is evidence that has yet to be collected, the conclusions may change. So it's a matter of the level of confidence one has in the result.

[Strange]

 

Thanks

Can you please advice what is the meaning of "is believed to be"?

"The radio source Sagittarius A* at the center of our Galaxy is believed to be a 2.6×10(6) M0 black hole that accretes gas from the winds of nearby stars."

 

 

It is believed to be: "a 2.6×10(6) M0 black hole that accretes gas from the winds of nearby stars"

 

 

However, why we have to believe?

 

Because of various lines of evidence.

 

 

 

Based on my understanding, the total mass of the SMBH had been set by the S2 orbit.

 

All of the stars can contribute to estimating the mass (and size) of the black hole. S2 has the shortest period and so its orbit is known most accurately.

 

 

 

So, technically I assume that the radio source has no effect on that mass.

 

I don't know what you mean by this. The radio source is the black hole. That is where the mass is.

 

 

Do we really see those stars?

 

You know we do. You have had one (or more) threads about them in the past.

http://www.astro.ucla.edu/~ghezgroup/gc/blackhole.html

 

 

What does it mean?

" 2.If the stars in the Galactic center are not randomly distributed around Sgr A* but instead have a large z-coordinate offset, the predicted accretion rate will be reduced. "

 

I think it means that if all the stars are to one side of the black hole, then the rate of accretion would be reduced. (But I may be wrong about that.)

 

 

If we see those stars, than we should easily know their distributed around Sgr A*.

 

We see them, but only in two dimensions; we can't measure their relative distances. So, for example, S1 could be in a highly elliptical orbit or in a nearly circular orbit that is tilted with respect to our line of site. (A circle seen edge-on is an ellipse.)

[David Levy]

You know we do. You have had one (or more) threads about them in the past.

http://www.astro.ucla.edu/~ghezgroup/gc/blackhole.html

 

Sorry.

I had the impression that we are speaking about new stars near the SMBH.

Now I understand that we discuss on S0... stars:

 

"The Galactic Center Group members have been measuring the positions of thousands of stars in the vicinity of the Galactic Center for more than 20 years. This unique data set allowed us to measure directly short-period orbits of stars. In particular, a full phase coverage has been measured for two stars: S0-2 with an orbital period of 15.56 years, and S0-102 with 11.5 years. At the closest approach, S0-2 is only 17 light hours away from the center of the Galaxy, about four times the distance of Neptune from the Sun. From these orbital data, we can determine the mass of the central black hole in our own Galaxy."

 

So, do you mean that those stars contribute some of their mass to the SMBH?

Out of those stars, S2 is the closest one. Do we see any indication on S2 which can confirm that it is losing its mass to the SMBH?

Our scientists were expecting for fireworks as G2 cloud came closers to the accretion disk.

Do we see any sort of fireworks as the SMBH eat some portion of S2 mass (especially at their closest spot)?

Edited March 24, 2017 by David Levy

[Strange]

So, do you mean that those stars contribute some of their mass to the SMBH?

Out of those stars, S2 is the closest one. Do we see any indication on S2 which can confirm that it is losing its mass to the SMBH?

 

 

All stars lose mass as "wind" - a stream of charged particles from their outer atmosphere. In the case of the stars around the black hole, some of this falls into accretion disk.

https://en.wikipedia.org/wiki/Solar_wind

 

http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?1991ApJ...382L..19K&data_type=PDF_HIGH&whole_paper=YES&type=PRINTER&filetype=.pdf

 

 

Do we see any sort of fireworks as the SMBH eat some portion of S2 mass (especially at their closest spot)?

 

Didn't you already post a reference to this?

"the Milky Way's black hole ... does have a small accretion disk, which produces a faint glow in visible, infrared, and other wavelengths."

http://blackholes.stardate.org/research/black-hole-binge.php.html

[David Levy]

All stars lose mass as "wind" - a stream of charged particles from their outer atmosphere. In the case of the stars around the black hole, some of this falls into accretion disk.

https://en.wikipedia.org/wiki/Solar_wind

 

The accretion rate per year is as follow:

http://iopscience.iop.org/article/10.1086/312035/fulltext/

"If we naively increase this by a (Bondi capture) factor of 2.62 to account for the actual mass of the central object, the theoretically predicted accretion rate becomes 10^-3 M yr^-1 (but see § 3)."

 

How could it be that all of this huge mass would be achived only by a "wind" from S0 stars?

Did we really try to calculate how this total requested mass can be accumulated by a stream of charged particles from S0 outer atmosphere?

 

Please be aware that this stream of charges is moving in all directions from S0 stars. Hence, technically, the total accumulated wind in the direction of the SMBH could be almost neglected.

Therefore, we must prove that this wind can carry 10^-3 M yr^-1 directly to the SMBH before we take it for granted.

 

After only one million year – the SMBH should accrete a total mass of:

10⁺³ M.

 

Hence, all the mass in S0 stars can't help to achieve that total mass.

If the SMBH eats S0 stars mass, then by definition all of them should be eaten long time ago.

Edited March 24, 2017 by David Levy

[swansont]

 

Please be aware that this stream of charges is moving in all directions from S0 stars.

 

 

Is it?

 

Many of the points you mention are addressed in your link.

[Strange]

Did we really try to calculate how this total requested mass can be accumulated by a stream of charged particles from S0 outer atmosphere?

 

That is exactly what that paper is all about. They use several models to calculate accretion rate and compare these with observed X-ray emissions. These all seem to produce roughly consistent results.

 

If you think there is an error in their modelling, feel free to show where it is (in appropriate mathematical detail).

 

Please be aware that this stream of charges is moving in all directions from S0 stars.

 

I'm not sure that is true. The wind from these stars may be affected by the presence of the black hole (but I don't understand the models in enough detail to know if that is the case or not).

 

Hence, technically, the total accumulated wind in the direction of the SMBH could be almost neglected.

 

I don't see how that follows as a logical argument. "Hence, technically, we can say that unicorns exist" is about as much of a non sequitur.

 

[David Levy]

 

That is exactly what that paper is all about. They use several models to calculate accretion rate and compare these with observed X-ray emissions. These all seem to produce roughly consistent results.

If you think there is an error in their modelling, feel free to show where it is (in appropriate mathematical detail).

 

I have already did:

 

 

After only one million year – the SMBH should accrete a total mass of:

10⁺³ M.

 

Hence, all the mass in S0 stars can't help to achieve that total mass.

If the SMBH eats S0 stars mass, then by definition all of them should be eaten long time ago.

 

Edited March 24, 2017 by David Levy

[swansont]

10⁺³ Mis quite small compared to the mass it already has, so what is this calculation supposed to show?

[Strange]

 

After only one million year – the SMBH should accrete a total mass of:

10⁺³ M.

 

 

I ignored this as I assumed it was a joke. You know, if babies double in size in one year, then by the time they are 10 they will be over 1,000 feet tall.

 

 

Hence, all the mass in S0 stars can't help to achieve that total mass.

If the SMBH eats S0 stars mass, then by definition all of them should be eaten long time ago.

 

So what this shows is that your naive extrapolation is wrong.

 

A couple of the more obvious omissions are:

• The mass of the stars involved: they are supergiants with masses of 20 to 100 solar mass.
• The stars have not always been there: stars migrate around the galaxy and stars are created
  • The Krabbe paper referred to earlier explicitly says that there has been star formation in the last million years
  • This paper talks about the possibility of star clusters migrating to the centre of the galaxy: http://iopscience.iop.org/article/10.1086/318054/pdf

[David Levy]

I ignored this as I assumed it was a joke. You know, if babies double in size in one year, then by the time they are 10 they will be over 1,000 feet tall.

 

Sorry, it isn't a joke and I really want to know why do you ignore it?

 

It is stated clearly:

 

http://iopscience.io...12035/fulltext/

"If we naively increase this by a (Bondi capture) factor of 2.62 to account for the actual mass of the central object, the theoretically predicted accretion rate becomes 10^-3 M yr-1."

 

So, based on my understanding the theoretically predicted accretion rate becomes 10^-3 M yr-1."

What is wrong with that?

I don't see any limit for time duration.

Do you claim that it is incorrect?

Do you claim that our scientists believe that in the past the theoretically predicted accretion rate was lower?

Can you please direct me to a relevant article?

 

Our SMBH isn't a baby. It is quite mature man.

His age is over 12 billion years and I hope that it can live few more billion years.

So one million years in SMBH life time is equivalent to less than one second in our life time.

Actually, even if we assume that the SMBH life time is only 12 Billion years and our life time is at least 120 years, than 100 million SMBH life time is equivalent to one year of man life.

Therefore:

If a man consumes 1500 calories per day (in average), can we assume that it consumes 1500 x 356 calories per year?

If our SMBH consumes 10^-3 M per year, why can't we assume that it consumes 10^-3 M x 1 Million, after one Million years???

Edited March 25, 2017 by David Levy