Dark matter annihilation detected

[Schneibster]

I claim nothing yet.....

But please note that if DM presence is found or theorized around galactic center (or any galaxy center), then the central SMBH may need some parameter dressing..

I don't see why. It seems pretty obvious to me why there would be more dark matter around a galactic center than in the disk: density, and consequent gravity.

And your claim is that "the central SMBH may need some parameter dressing," and you have not substantiated it. Care to?

 

[The God]

I don't see why. It seems pretty obvious to me why there would be more dark matter around a galactic center than in the disk: density, and consequent gravity.

If It was 'pretty obvious' then you should have proposed it prior to this...and please note that this is being worked out and not established yet.

And your claim is that "the central SMBH may need some parameter dressing," and you have not substantiated it. Care to?

That would not be my claim. It is pretty obvious to decipher that. The parameters of our SMBH at GC are determined based on the orbital motion of nearby objects.....you pump in some DM around GC and the only thing which would require adjustment is SMBH...To me it appears very straightforward and obvious. Who knows some intelligent mathematician can come up with some explanation for all the observed orbital motions of those objects with a feasible DM distribution near GC and BH is dumped ?

 

[Schneibster]

If It was 'pretty obvious' then you should have proposed it prior to this...and please note that this is being worked out and not established yet.

I can't predict your arguments; and I note you have no response other than attempted obfuscation. Show why dark matter would not be affected by gravity since it interacts with matter by gravity.

That would not be my claim.

Yes, it is; you claimed it, you said so. You said, "the central SMBH may need some parameter dressing." That's a claim. And you still have not substantiated it, which seems to be a habit with you.

The parameters of our SMBH at GC are determined based on the orbital motion of nearby objects.....you pump in some DM around GC and the only thing which would require adjustment is SMBH...

Why would there need to be any correction? The quantity of DM need not be enough to be gravitationally significant in the near neighborhood of a SMBH, to be detectable by its emission of gamma rays due to DM-anti-DM annihilation.

To me it appears very straightforward and obvious. Who knows some intelligent mathematician can come up with some explanation for all the observed orbital motions of those objects with a feasible DM distribution near GC and BH is dumped ?

They don't need to; there's a perfectly obvious SMBH there, plus the mass of the GC, to account for everything.

You're making up problems that don't exist in order to try to equivocate about detected data that have no other reasonable explanation than DM. This isn't arguing, it's obfuscation.

 

[danshawen]

The Wikipedia article on dark matter details the discovery by Zwicky in 1933, and the predictions by Kapteyn and Oort before that, and the Wikipedia article on Vera Rubin gives her birth date. Do you need links to these articles?

I'm glad you feel my points were well-reasoned, but I have to point out that you didn't further explain your claim that there was a contradiction. If you are withdrawing that claim please do me the favor of acknowledging that.

Zwicky is important for more than "dark matter", but in more modern astrophysics parlance, his description appears unrelated to Rubin's anomalous galactic rotation, to which Zwicky might only rate a footnote in terms of any real contribution to our understanding of what dark matter is needed to explain.

You have used the term "fermionic" in place of the more commonly understood "baryonic", but the meaning is clear enough.

My point was that if there is an imbalance in the relative abundances of baryonic matter vs antimatter, and if it should turn out that there is NOT an imbalance in dark matter vs dark antimatter, then any theory which purports to predict less antimatter than matter would require a bold revision. As far as I can tell, you have not directly disputed this.

Welcome to sciforums, by the way.

 

[The God]

I can't predict your arguments; and I note you have no response other than attempted obfuscation. Show why dark matter would not be affected by gravity since it interacts with matter by gravity.

Yes, it is; you claimed it, you said so. You said, "the central SMBH may need some parameter dressing." That's a claim. And you still have not substantiated it, which seems to be a habit with you.

Why would there need to be any correction? The quantity of DM need not be enough to be gravitationally significant in the near neighborhood of a SMBH , to be detectable by its emission of gamma rays due to DM-anti-DM annihilation.

They don't need to; there's a perfectly obvious SMBH there, plus the mass of the GC, to account for everything.

You're making up problems that don't exist in order to try to equivocate about detected data that have no other reasonable explanation than DM. This isn't arguing, it's obfuscation.

How do you know about my habits ? You joined probably just yesterday only....Someone tutored you in advance ?

The second highlight shows wriggling out....

 

[Schneibster]

Zwicky is important for more than "dark matter", but in more modern astrophysics parlance, his description appears unrelated to Rubin's anomalous galactic rotation, to which Zwicky might only rate a footnote in terms of any real contribution to our understanding of what dark matter is needed to explain.

Let's see what Wikipedia says:

In 1933, Swiss astrophysicist Fritz Zwicky, who studied galactic clusters while working at the California Institute of Technology, made a similar inference. Zwicky applied the virial theorem to the Coma cluster and obtained evidence of unseen mass that he called dunkle Materie 'dark matter'. Zwicky estimated its mass based on the motions of galaxies near its edge and compared that to an estimate based on its brightness and number of galaxies. He estimated that the cluster had about 400 times more mass than was visually observable. The gravity effect of the visible galaxies was far too small for such fast orbits, thus mass must be hidden from view. Based on these conclusions, Zwicky inferred that some unseen matter provided the mass and associated gravitation attraction to hold the cluster together. This was the first formal inference about the existence of dark matter.

You have incorrectly believed that the galactic rotation problem is the only problem DM solves. In fact, there are multiple problems it solves, and Zwicky discovered the first of them: galactic orbits within a galactic cluster. Rubin discovered another: anomalous rotation curves of galaxies.

You have used the term "fermionic" in place of the more commonly understood "baryonic", but the meaning is clear enough.

I used it quite deliberately and avoided "baryonic" since it would have entangled badly with the discussion on the abundance (or lack thereof) of anti-DM, and since the baryons do not include electrons. There is as much a dearth of positrons as of anti-baryons, and it is more accurate to speak of the dearth of anti-fermions than to concentrate on the baryons.

My point was that if there is an imbalance in the relative abundances of baryonic matter vs antimatter, and if it should turn out that there is NOT an imbalance in dark matter vs dark antimatter, then any theory which purports to predict less antimatter than matter would require a bold revision. As far as I can tell, you have not directly disputed this.

I did, in two points in my first post. Please see that post and respond if you wish to rather than doing so without quoting me. Thanks in advance.

Welcome to sciforums, by the way.

Thanks.

 

[Schneibster]

How do you know about my habits ? You joined probably just yesterday only....Someone tutored you in advance ?

No, you used two logical fallacies and attempted to shift the burden of proof, and I note the same tactics in other posts you have made on this forum.

The second highlight shows wriggling out....

Yep. That's your fault; don't leave a hole.

Can we talk about DM annihilation again now? Because you are off-topic for this thread. It's not about me, it's about DM annihilation. Please see the thread title.

 

[danshawen]

Let's see what Wikipedia says:

You have incorrectly believed that the galactic rotation problem is the only problem DM solves. In fact, there are multiple problems it solves, and Zwicky discovered the first of them: galactic orbits within a galactic cluster. Rubin discovered another: anomalous rotation curves of galaxies.

I used it quite deliberately and avoided "baryonic" since it would have entangled badly with the discussion on the abundance (or lack thereof) of anti-DM, and since the baryons do not include electrons. There is as much a dearth of positrons as of anti-baryons, and it is more accurate to speak of the dearth of anti-fermions than to concentrate on the baryons.

I did, in two points in my first post. Please see that post and respond if you wish to rather than doing so without quoting me. Thanks in advance.

Thanks.

I concede your point (that a change in a theory that explains the relative balance of matter, antimatter would not take away from a theory which explains the relative balance of matter, antimatter in fermionic, particularly Majorana fermionic domains). I understand that the two domains cannot be combined because of their different physical behaviors.

Thanks too for clearing up my Zwicky question in a clear and concise manner that I am unaccustomed to seeing here from anyone other than rpenner, and occasionally Farsight.

 

[Schneibster]

You're welcome, and thanks for showing reason in the DM/anti-DM question. Not everyone can do that.

You might start a thread about the matter/antimatter imbalance and ask about fermions and why I used that terminology in this case. I'll do my best for you. It would, in my opinion, be off-topic in this thread.

 

[The God]

The parameters of our SMBH at GC are determined based on the orbital motion of nearby objects.....you pump in some DM around GC and the only thing which would require adjustment is SMBH

Why would there need to be any correction? The quantity of DM need not be enough to be gravitationally significant in the near neighborhood of a SMBH,

Somewhere else you say that DM influences orbital motion......

........DM solves. In fact, there are multiple problems it solves, and Zwicky discovered the first of them: galactic orbits within a galactic cluster. Rubin discovered another:

 

[pmbphy]

Some astronomers have speculated that dark matter might have another property besides gravity in common with ordinary matter: It might come in two flavors, matter and anti-matter, that annihilate and emit high energy radiation when coming into contact. The leading class of particles in this category are called weakly interacting massive particles (WIMPS). If dark matter annihilation does occur, the range of options for the theoretical nature of dark matter would be considerably narrowed.
CfA astronomer Doug Finkbeiner and a team of colleagues believe they may have uncovered evidence of dark matter annihilation occurring at the center of the galaxy, while studying the spatial distribution of gamma-ray emission in the Milky Way, which could help us resolve the issue of what dark matter really is.

http://futurism.com/harvard-scientists-say-may-detected-dark-matter-annihilation/
http://phys.org/news/2016-03-signature-dark-annihilation.html

Note: A word of caution. When considering matter-antimatter annihilation. People often get the idea that the same thing that happens with electron-positron annihilation also happens with all particle-antiparticle annihilation, i.e. that it all results entirely of photons. That's not true. For details please see: https://en.wikipedia.org/wiki/Annihilation#Proton-antiproton_annihilation

 

[paddoboy]

As far as BICEP2's initial reporting, and later retraction, of the claim to have found the signature of gravity waves in B-mode polarization of the CMB, the problem with it was caused by interstellar dust in our own galaxy, which they used the best available data at the time to estimate. That data turned out to be wrong, as shown by the Planck data set, and they promptly retracted when this new data became available. Neither faulty instrumentation, nor misuse of instrumentation, had anything to do with it. Nor did they behave like unruly children.

Yeah we had the would be pretenders latch quickly on to that one also, with all sorts of derisive comments re the supposed state of science.
All without realising that it was mainstream science itself that self corrected the BICEP2 error....and example in fact, of good science doing what it does best...self correction.

I claim nothing yet.....
But please note that if DM presence is found or theorized around galactic center (or any galaxy center), then the central SMBH may need some parameter dressing..

I wouldn't confuse yourself with BH's anymore then you already have my friend...particularly the SMBH variety.
After your past monumental errors of the most basic postulates of BH's, like denying the "no hair theorem" and compulsory collapse once the Schwarzchild radius is reached, you certainly need to study and read up more on these awesome beasts.

 

[expletives deleted]

Can any learned member explain for me what the interaction cross-section would look like in a postulated Dark Matter-Antidark-Matter annihilation collision? For example, with electron-positron matter-antimatter collisions their electromagnetic fields configurations interact and reform into gamma-ray configurations. What 'field(s)' actually "collide" in the postulated Dark Matter-Antidark-Matter annihilation collision? And what is the reformed configuration of those post annihilation 'field(s)'? Thanks.

 

[The God]

I wouldn't confuse yourself with BH's anymore then you already have my friend...particularly the SMBH variety.
After your past monumental errors of the most basic postulates of BH's, like denying the "no hair theorem" and compulsory collapse once the Schwarzchild radius is reached, you certainly need to study and read up more on these awesome beasts.

please take a walk....

 

[Schneibster]

Can any learned member explain for me what the interaction cross-section would look like in a postulated Dark Matter-Antidark-Matter annihilation collision?

From the abstract of the paper linked in the OP:

For example, the signal is very well fit by a 36–51 GeV dark matter particle annihilating to

bb̄ with an annihilation cross section of

σv=(1−3)×10−26cm3/s (normalized to a local dark matter density of

0.4GeV/cm3).

Link: http://www.sciencedirect.com/science/article/pii/S2212686416000030

 

[surreptitious57]

Dark matter like ordinary matter interacts with gravity and is why it is known to exist. Though it is practically
impossible to contain and no attempt at doing so has so far been successful. Until this can be overcome it will
continue to remain as elusive as ever. Ironically it is not actually hard to detect for it regularly passes through
Earth and is much more abundant than ordinary matter which is just four per cent of the observable universe

 

[paddoboy]

please take a walk....

Are you denying anything I have said?
It maybe embarrassing but you certainly have made some incredible bad statements re BH's.

 

[paddoboy]

I can't predict your arguments; and I note you have no response other than attempted obfuscation. Show why dark matter would not be affected by gravity since it interacts with matter by gravity.

Yes, it is; you claimed it, you said so. You said, "the central SMBH may need some parameter dressing." That's a claim. And you still have not substantiated it, which seems to be a habit with you.

Why would there need to be any correction? The quantity of DM need not be enough to be gravitationally significant in the near neighborhood of a SMBH, to be detectable by its emission of gamma rays due to DM-anti-DM annihilation.

They don't need to; there's a perfectly obvious SMBH there, plus the mass of the GC, to account for everything.

You're making up problems that don't exist in order to try to equivocate about detected data that have no other reasonable explanation than DM. This isn't arguing, it's obfuscation.

That methodology appears to be the general methodology most of our YEC's and God Botherers often use.