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PRL endorses a pro-DAMA model of dark matter

An hour ago, Physics World decided to promote a paper claiming that dark matter may have already been seen:

New calculations support dark-matter discovery by DAMA, say physicists
The relevant paper has just appeared in the prestigious Physical Review Letters under the title
Dark Matter with Pseudoscalar-Mediated Interactions Explains the DAMA Signal and the Galactic Center Excess
although the readers who have memorized all 1 million preprints at arXiv.org know very well that the identical paper was submitted under a different title,
Not so Coy Dark Matter explains DAMA (and the Galactic Center excess)
in June 2014. Recall that in October 2013, LUX has pretty much won the "dark matter is not seen" war and excluded lots of theories with light dark matter particles that were suggested by the positive experiments from the opposing alliance in the war.




However, DAMA – an old team that has claimed the observation of dark matter – claims that they still see their signal whose significance has grown above 9 sigma. Their signal depends on seasons – it is maximized in June and minimized in December. Others are convinced that the right interpretation of this annual modulation has to be mundane and unrelated to dark matter.




The (not quite) new PRL paper by Eugenio Del Nobile and two collaborators, Arina and Panci, claims that they can still explain the DAMA signal by a model where the dark matter interaction with the nuclei proceeds via an intermediate pseudoscalar particle, an axion, if you wish. Its mass should be comparable to an \(\MeV\). Meanwhile, the dark matter particle itself is between \(20\) and \(40\GeV\). But the uncertainty about most parameters seems to be large.



Their model circumvents the simple spin-independent form of the interactions that is apparently excluded by the other, negative experiments, while it predicts a large enough signal for DAMA and it offers an explanation for the Galactic center excess of gamma rays around \(1\)-\(3\GeV\). Del Nobile and pals stress that the experimenters should start to more explicitly articulate their assumptions about the dark matter interactions that they are excluding.

Juan Collar of the "dark matter is seen" experiment CoGeNT thinks that a simpler way to reconcile the positive results from DAMA with the negative results from others is to assume that DAMA sees the interactions of the dark matter with the electrons rather than nuclei.

Lots of questions concerning the detection of the dark matter particle remain confusing...

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reader PlatoHagel said...

.....be interesting to see how this axion approach may help in understanding the sun and QGP.


reader Gene Day said...

A QGP (quark-gluon plasma) exists at temperatures about five orders of magnitude higher than anything within the sun. What are you talking about?


reader Uncle Al said...

Spiral galaxies' Tully–Fisher relation is Milgrom acceleration. "Dark matter" is curve fitting. Noether's theorems exclude discontinuous symmetry mirrored coordinate axes.

Vacuum supersonic expand racemic 4-oxa-D_3-trishomocubane vapor (dipole moment). View its microwave rotational spectrum (temperature). Enantiomers' divergent temperatures source Milgrom acceleration, 1.2×10^(-10) angular momentum conservation Noetherian leakage, from trace vacuum chiral anisotropy toward fermion quarks (hadrons are not boson photons).

If physics had great bolshy yarblockos, it would look.


reader pEGO said...

I think
that dark matter couldn’t be seen because of that is time shift


reader NikFromNYC said...

Tip: Kickstarter.com

https://www.thewinnower.com/papers/testing-exact-vacuum-mirror-symmetry-toward-matter


reader Quantum said...

But the blackbody formula only works in the limit where the photons within the cavity are noninteracting, which is integrable.


reader Sal said...

PRL must be trying to compensate for the recent publication of a letter explaining DAMA away based on solar neutrino interactions. It was wrong by a mere seven orders of magnitude.


reader David Nataf said...

It's like crackpot heaven in these comments.


reader Gordon said...

Interesting quote from Freeman Dyson over now 30 years ago-- ‘I have a sneaking hope, a hope unsupported by any facts or any evidence, that sometime in the twenty-first century physicists will stumble upon the Monster group, built in some unsuspected way into the structure of the
universe.’


reader Tony said...

Ohio State won because they respected Eotvos experiment. Suck it Uncle Al, you lost.


reader Luboš Motl said...

I didn't really criticize "just Obama" for not attending - I criticized the American government and the absence was just the mildest among the criticisms.


Russia was represented by Sergey Lavrov, foreign affairs minister, who is a heavyweight.


reader davideisenstadt said...

One always must ask...superior to what, exactly?
the Egyptian way?
the way of the house of saud?
the french way?
funny how it has come back to the US, time and time again to show the way...a republic in Germany...freedom for the french...a peaceful government not murderingand enslaving its neighbors for Japan.
a modern s korea.
whats your alternative?


reader davideisenstadt said...

here in the states we see that there is no difference...see the westboro baptist church, for example, of the nazis' march in skokie....or the blind sheik's rants in north jersey.
Do you think any of that would be allowed in saudi arabia (I mean the westboro church, obviously nazi sentiments and the blind sheik's hate filled rhetoric would be okay there)
BTW hear a lot of church bells in saudi arabia on a sunday?
no.


reader pEGO said...

Anyway I
think that dark matter could be simulated on PC. I have simple algorithm to
check. If there is interest in I could make presentation how to simulate on
Matlab/Simulink with algorithm and explanation. Unfortunately I do not have
time presently for it due to my Calabi Yau project and scientific presentation of
my developed fractal RTDG for n-dimensional enlargement, but if there is
interest this presentation how by my opinion dark matter could be simulated I
will do first.


reader monster said...

Dear Lubos,

what is a bit odd (or great, depending on the correctness of the claim) is to be able to have access directly to the order of the monster group and not just to the dimensions of the irreducible representations. If one knows the exact structure of the representation of the monster on the Hilbert space of the CFT and the precise correspondence between this Hilbert space and the black holes states, then it should be possible to extract an asymptotic expansion for each of the 194 irreducible representations of the monster, and so to recover the order of the monster as the sum of the squares of these dimensions. But I guess it is not the way you proceed, right?
In this reasoning, one only uses the fact that the monster group acts in some way on the Hilbert space of the theory. I guess you use a much stronger statement, that the monster group is exactly the group of symmetries of the CFT, and so of the dual gravity theory.

Given an Einstein-Rosen bridge connecting two black holes, does it make sense to act by elements of the monster group on one of the black holes, keeping the state of the other fixed, in order to "twist" the bridge?


reader Luboš Motl said...

Dear Monster, good ideas. I was trying to get access to the dimensions directly but I think that only the smallest one has a simple expression.


Note that 196883 is approximately exp(4*pi). The 193 larger irreps are more mixed with each other and I have doubts that there is anything canonical about their ordering, for example.


You know that but for others, the order of the group, N = 8 x 10^{53}, is the sum


N = sum(194 terms) dim(i)^2


of the squared dimensions, by the Schur's lemma.


reader Alex said...

60 years ago the US was a different place. The American dream and way of life was admired by many. Since then the reality of the way the US handles things has deteriorated. The world has changed. What worked in the past does not work now. As a kid, I thought living in the US would be the best thing. I grew up and watched the US change. What I see now, I don't like. I don't want to even visit the place now. I have been there several times. I liked it less each time. I think most Americans have thoughts of the 'glory days' of the US when, perhaps, the US was superior in many things. That's not the case now.
As to my alternative:
Be like you were in both world wars. Come in last instead of first. You might then be considered the 'heroes' who saved the day instead of the a'holes who started things.


reader Philip Weisler said...

What has never ceased to astonish me is the immense ethical perversity of Islam, its Prophet and its Idol Allah.

I mean, in Christianity, some of the things that makes for a good human being is ''loving thy neighbour'' or even your enemy etc. Christian ethics is not completely wrong.

However, it would really put shame on the ''Deity'' or ''Supreme Being'', if it indeed were this ''Allah''. 95% of the Quranic ''ethics'' is blindly following this Allah and hating, hatin, hating the ''infidels''. Killing as many infidels as possible is the most ethical thing one could do in Islam's teaching. Now what kind of a ''perfect being'' would create men, divide those into believers and infidels and urge the former to torment the latter. This is absurd. Islam's God is not really a God but Satan rather.


reader Alex said...

Actually he is not so naive. The religious teachings in fact state what he says. Read a little of the bible and you will notice. I am not a religious person but I did study for the priesthood in my youth. Your last sentence is a little silly. It should go without saying that atheists or disbelievers would think that something referred to as sacred would be BS


reader Alex said...

I have been alive long enough to become really cynical about humanity. The 'I am Charlie' thing will be over when they have sold all the T-shirts and the masses will be distracted by the next squirrel. Unfortunate. Few will 'maintain the rage'.


reader Shannon said...

Alex, you must have read the Bible for kids only. It's a good one too, don't get me wrong ;-).


reader Alex said...

You're so sweet and naive


reader Fer137 said...

I tend to think that Islam, like other religions, is one of those memes (In the original sense) that Dawking mentioned in his old book 'selfish gene'.

Some of the features that make extended this meme are the holy war, the promise paradise for the murderers of other memes, etc. An negative and agressive meme, dangerous for other much better memes. It could also be viewed from the perspective of game theory.


reader Shannon said...

Philip, what you describe is the fundamentalism of Islam.
"Loving thy neighbour" is also muslim. Muslim people are very welcoming, they invite you at their table whoever you are and are happy to share their home with you.
Our French Abbot Pierre used to say that "Fundamentalism is a refuge for poverty because it gives a sudden burst of hope to those who have nothing. Should their harm disappears and they will lose their troops".


reader Vangel said...

Most ordinary Americans are decent people. The problem is not the people but the government which is pushing a certain agenda and is distorting the culture by incentivising the worst and silencing the best.


reader Shannon said...

;-)


reader Shannon said...

We really are expecting our elected politicians to "maintain the rage" and start putting new policies into place because "we" people have to earn a living.


reader Alex said...

Good luck with that thought. I, for one, am not holding my breath.


reader Fer137 said...

I also think that when shouting "allah is great" must feel as if they themselves would feel larger. Some kind of rudimentary self-gratifying psychological mechanism.


reader Vangel said...

"What has never ceased to astonish me is the immense ethical perversity of Islam, its Prophet and its Idol Allah."



I do not see this at all. Most Muslims are not very different than most Christians and have pretty much the same day to day concerns. While the 'backwards' Muslims may not have embraced drug use, pornography, and other staples of modern Wester culture I am sure that those things will be embraced by the next generation just as they were embraced in the West.


But anyone who wishes to lecture Muslims on ethical perversity might want to consider having our video game operators kill innocent women and children by shooting missiles at a wedding party, invading and occupying a country simply because we don't like its leadership, or using our planes to act as al Qaeda's air force. They might want to see what the English have done to the Irish, what Belgium did in the Congo, or what the Nazis did to the Jews, Roma, Slavs, etc. They do not have to go back very far. We still have great examples of American atrocities in Vietnam, Laos, and Cambodia, French atrocities in Africa and IndoChina, or even the Jewish terrorist attacks against the British and Palestinians.


We need to stop pretending that we are pure and holy and start to see all individual actions that initiate force as unacceptable.


reader Θ³Σx² - ∂³Σx² - ΘΣ said...

Pretty interesting, but it is a mediatic claim...Until some experiment and a similar in proceedings and structure can reply it and its results, all we get are "hints" and lots of speculative models. Of course we have excluded tens, maybe hundreds of models with the aid of the LHC, detection experiments and so on, but it is not enough YET. Too many questions...And even it is likely that the DAMA signal could be some kind of "(solar?) neutrino" signal...In the next years, detection experiments will approach the limit of neutral coherent neutrino-nuclei scattering limits, so we well get dark matter detectors turned into "neutrino detectors" if not a clear DM signal appears. We will need DIRECTIONAL dark matter detectors. An idea to such a device using carbon nanotubes was recently added into the arxiv. A fascinating topic...How dark matter detection will converge with neutrino astronomy in the next years.


reader Shannon said...

No he didn't go because 17 shot dead is no big deal. In the US you get that every week :-)


reader Alex said...

Islam was designed for a simple world, much like all religions. The world was local, at most regional, You needed to state the obvious for simple people so you made God/man laws and it gave you authority over their behaviour. Problem is that the world is bigger/smaller now. So now we have a 'fuckfest' till people of low intelligence work things out. Unfortunately that will take a few generations.


reader Shannon said...

You must be a very funny guy to be around Alex :-).


reader RMB said...

Read it and weep:

http://en.wikipedia.org/wiki/Muslim_attitudes_towards_terrorism


reader John Archer said...

None of which addresses the point in the quote cited at the head of your post.

People's humanity is one thing and will be expressed in many ways, both good and bad, but it can be affected by a system of beliefs.

You have NOT responded in any way at all to the point which you purport to address.


reader Alex said...

So I have been told


reader Shannon said...

RMB, the Coran does need a sequel alright (like the Bible has the first and the new Testaments)... don't forget that the muslim world is only in 1437 and they already have internet, pick up trucks and kalachnikovs. And sin is a universal, timeless reality.
Let's give them a chance and help them build this new Islam.
http://cdn.pmnewsnigeria.com/wp-content/uploads/2015/01/Australia.jpg


reader RMB said...

Just reporting the facts Shannon. You, of course, can give them as long as you like.


reader Vangel said...

Why is maintaining rage a positive? And rage against what?

Note that most Muslims in France reject these types of actions, even those that do not hate al Qaeda or ISIS enough to make us comfortable. Rage is what caused this problem in the first place and is the last thing that we need to maintain.

Please note that the moral relativists on the left are wrong about the materialist theory of action. Revolutionaries are not driven by material conditions but by moral judgments that fuel reaction against injustice no matter what its source. The planners at ISIS and al Qaeda understand this and are choosing soft targets in order to provoke reactions against ordinary peace-loving Muslims so that they can generate the type of resentment that helps their recruitment drives.


reader Uncle Al said...

"scores of millions of dead don't count" When have they ever mattered? 30 million New World indigenes were killed for Christ. The dead never complain.


reader Shannon said...

Thanks for these interesting statistics, and not very surprising results don't you think ? What do you think the answer to the question would have been in Israel? (Note: this is not a provocation, or a "bait" type of question I am asking alright (Gordon and David) ? Never is btw).


reader RMB said...

I don't know Shannon. I think virtually all Israelis would condemn suicide bombing against Palestinians, but I suspect you'd say that too is to be expected given the asymmetric power relationship. My intuition is that a far higher percentage of Israelis would oppose any violence directed against Palestinian civilians. But the operative word, of course, is "directed" -- and I'm certain that a long debate considering power relationships, strategies, tactics and history no doubt would then ensue. But even if Israeli public opinion was as medieval as that in the Muslim world, what's the point? If this were the case then they would be just as crazy.


reader Swine flu said...

Before you can maintain "rage", or rather determination, you have to define the problem. Radical Islam appears to be the problem. When it chooses violence as its tool, it is easily recognized, and while violence does sometimes allow it to achieve its objective, it also produces greater opposition. The non-violent approach is more in the a nature of boiling a frog and can be hard to spot and hard to stop. Yet, if the West is to retain its culture, it must be committed to its preservation, and that kind of "rage"/determination is not easily maintained.


reader Swine flu said...

Leaving all issues of national 'glory' and superiority aside, and focusing just on the practical issues, the US may still be in a relatively decent position as far as its economic prospects for the next 20 years go. It has a fairly large and relatively young population, and secluded geography. If it finds the will to reduce its commitments to providing security guarantees to non-essential allies, it should be able to do fairly well.

Due to the ongoing erosion of freedom in the US, I am less enchanted with it than I used to be, but in relative terms I think it's still among the better places to live, especially if one considers the prospects of various other candidate countries.


reader Leo Vuyk said...

IMHO, Dark Matter is already seen as we accept
the idea that dark matter is the same as black holes able to have microscopic (ball lightning) up to giant proportions. See:

The “Impossible” Electric Dark Matter Black Hole as the Origin of New Physics even for Comets like 67P,C-G.

https://www.researchgate.net/publication/265080005_The_Impossible_Electric_Dark_Matter_Black_Hole_as_the_Origin_of_New_Physics_even_for_Comets_like_67PC-G


reader Uncle Al said...

(Winnower display does not yet support a vast swath of text formatting.) The universe must be fundamentally mirror symmetric! There is no need to look. I disagree. I present a collection of suitably sensitive experiments to find out.


reader JustGuest said...

Why do we have laws against denial of holocaust and not against denial of 2+2=4? I consider separation of religion from state as one of the greatest achievements of european society, yet I don't understand why we can't have Nazi party like people in the USA. Can someone elaborate?


reader davideisenstadt said...

one death is a tragedy...a million dead is a statistic.


reader Fer137 said...

"...le 14 janvier 1975" Exactly 40 years ago. It would be good time to complete this post.


reader guest said...

So Garrett Lisi was not a crackpot after all ?

http://arxiv.org/pdf/0711.0770.pdf


reader Luboš Motl said...

Hi, I assure you that Garrett Lisi was a crackpot of every moment of his life so far.

http://motls.blogspot.com/2007/11/exceptionally-simple-theory-of.html?m=1



The exceptional groups were not invented by Garrett Lisi - they have been around since the 19th century - and their application to particle physics wasn't invented by Garrett Lisi - it's the paradigm of grand unification from the 1970s.


The usage of E8 as master group for GUT wasn't invented by Lisi, it naturally appeared in 1985 in heterotic string theory, string theory's first class of realistic models of the Universe.


Lisi only wrote some new things about what else may be done with the E8, and how this E8 may also include gravity, and so on. Unfortunatelly, all these new claims are and have always been 100% rubbish.


reader PlatoHagel said...

I guess you never heard of quantum Chromodynamics.....the history.

https://www.youtube.com/watch?v=eLhmUYiDjrU

There is a correlation between what they are doing with the theoretic regarding the sun and what is happening with the QGP.

http://iaxo.web.cern.ch/

"The central component of iAXo is a superconducting toroid magnet. The
detector relies on a high magnetic field distributed across a large
volume to convert solar axions to detectable X-ray photons. The magnet’s
figure of merit is proportional to the square of the product of
magnetic field and length, multiplied by the cross-sectional area filled
with the magnetic field.IAXO: the International Axion Observatory -Pg 9 Sept 2014(PDF)" http://iopp.fileburst.com/ccr/archive/CERNCourier2014Sep-digitaledition.pdf