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Theo Nieuwenhuizen: on 10/4/12 at 19:20pm UTC, wrote Dear Sergei and Renate, thanks for pointing this out to me. I was not...

Theo Nieuwenhuizen: on 10/4/12 at 17:54pm UTC, wrote Dear Ben, it is a relief to receive such understanding words. Most of the...

Renate Quehenberger: on 10/4/12 at 7:50am UTC, wrote Dear Theo, I see: with Sergey Fedosins creative calculative comment on...

Sergey Fedosin: on 10/4/12 at 4:32am UTC, wrote If you do not understand why your rating dropped down. As I found ratings...

Benjamin Dribus: on 10/3/12 at 20:08pm UTC, wrote Dear Theo, I am particularly grateful for your essay, if only because...

Theo Nieuwenhuizen: on 10/2/12 at 8:15am UTC, wrote Dear Jim, in the essay I have discussed galaxy mergers like Tadpole and...

Sergey Fedosin: on 10/2/12 at 7:35am UTC, wrote After studying about 250 essays in this contest, I realize now, how can I...

Hoang Hai: on 10/1/12 at 3:20am UTC, wrote Dear Theodorus Maria Nieuwenhuizen Very interesting to see your essay. ...


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FQXi FORUM
July 19, 2019

CATEGORY: Questioning the Foundations Essay Contest (2012) [back]
TOPIC: Thousand-and-One Challenges for Cold Dark Matter Solved by MACHO Plus Neutrino Dark Matter by Theodorus Maria Nieuwenhuizen [refresh]
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Author Theodorus Maria Nieuwenhuizen wrote on Sep. 4, 2012 @ 15:59 GMT
Essay Abstract

While cosmological inputs like the cosmic microwave background and the baryon-acoustic oscillations yield a clear support for the Lambda Cold Dark Matter model, the small scale (galaxies and dwarf galaxies) poses serious challenges. A way out is offered by gravitational hydrodynamics, that connects galactic dark matter with the missing baryon problem. The resulting picture puts forward that galactic halos consist of millions of Jeans clusters, each of which contains billions of Machos of Earth mass. It explains many observations that challenge LCDM. Next, the absence of CDM in the Galaxy demands a new form of non-baryonic dark matter. Weak and strong lensing by the galaxy cluster Abell 1689 can be described by quantum degenerate neutrinos of 1.5 eV mass. When non-degenerate, that is, outside centers of galaxy clusters, they behave much like cold dark matter, which explains some of the successes of the latter.

Author Bio

The author is a researcher with experience in many fields of physics, such as the statistical physics of random systems, condensed matter, multiple light scattering, thermodynamics of spin glasses and glasses, biophysics, quantum thermodynamics, quantum optics and quantum measurements. In last years he focussed on cosmology, in particular the nature of dark matter. Generally, he feels that simple ideas should be considered first, an attitude that has been fruitful several times in his career.

Download Essay PDF File

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Anton Lorenz Vrba wrote on Sep. 5, 2012 @ 08:20 GMT
Hi Theo,

Many of your acronyms I had to google, e.g. MACHO I now learned to be a m(assive) a(strophysical) c(ompact) h(alo) o(bject). That a WIMP is a w(eakly) i(nteracting) m(assive) p(article) I happened to know.

I tried to comprehend your essay but you loose me with the following statement "Gravitational hydrodynamics (GHD) predicts that the Jeans clumps fragmented in H-He clumps of earth mass, turning them into Jeans clusters (JCs) of some 13 billion micro brown dwarfs (uBDs), the MACHOs." Can you please elaborate.

Referring to your bio you feel that simple ideas should be considered first, I too prefer simpler Ansätze to theories as demonstrated in my essay Rethinking Geometry and Experience

Regards

Anton

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Theo Nieuwenhuizen replied on Sep. 8, 2012 @ 20:01 GMT
The Jeans instability implies that after the recombination, the newly formed gas is unstable at the Jeans length. Thus Jeans clumps of gas arise with mass of the order 40.000 solar masses. Gravitational hydrodynamics puts forward that the Jeans clumps themselves also fragment, in objects of Earth mass. One name of the names given to these MACHOs is micro brown dwarfs, because they weigh about one millionth of the Sun. They should still exist, and be visible in e.g. microlensing. Since they are started as primordial H-He gas clumps, and cannot have changed much, they should not be colder than 13.8 K, which explains the ubiquitous 15 K observations.

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Jayakar Johnson Joseph wrote on Sep. 5, 2012 @ 13:40 GMT
Dear Theodorus Maria Nieuwenhuizen,

Baryon acoustic oscillations of universe is indicative of homeomorphic segmental fluctuations in Coherently-cyclic cluster-matter universe model, in that categorisation of dark matter as Hot dark matter, Warm dark matter and Cold dark matter and their variants in-between, that are observational by an observer cluster-matter in a locality, is suggestive of holarchial clustering of matters described in this model.

With best wishes,

Jayakar

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James T. Dwyer wrote on Sep. 5, 2012 @ 17:20 GMT
Hi Theodorus Maria,

I urge you to read my brief essay, Inappropriate Application of Kepler's Empirical Laws of Planetary Motion to Spiral Galaxies Created the Perceived Galaxy Rotation Problem - Thereby Establishing a Galactic Presence for the Elusive, Inferred Dark Matter.

As I understand, the principal requirement for galactic dark matter is that it produce the observed relatively flat galaxy rotation curves by (improperly) applying Keplerian relations. This is thought to be achieved by significantly increasing galactic diameters with dark matter and increasing total galactic mass up to 10-fold, predominantly at the galaxy periphery. Please see the artist's renderings of a Milky Way DM halo configured to achieve this requirement: Serious Blow to Dark Matter Theories?

As I understand, a configuration of MACHOs that achieved the necessary mass distribution would produce a disperse halo of massive objects. There would have to be some explanation for why those massive objects would not gravitationally interact with other massive objects to migrate to the galaxy disk or bulge.

Moreover, the presence of discrete objects of mass in a vast 'dark' galactic halo would most likely indicate their presence by perturbing the motions of individual objects within the periphery of the galactic disk and, especially the hundreds of discrete ordinary objects observed within the Milky Way galactic halo.

IMO, the requirement for compensatory galactic mass was improperly identified. Even if I'm wrong about that, I don't htink that configurations of MACHOs could meet the requirements specified for galactic dark matter halos.

Thanks for your consideration.

Jim

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Theo Nieuwenhuizen replied on Sep. 8, 2012 @ 20:54 GMT
Jim, you touch relevant questions. Let me recall that in my theory, billions of MACHOs are packed together in Jeans clusters, which makes them mutually gravitationally stable. Then a few million Jeans clusters constitute the Galactic dark matter halo which by itself is also stable. The halo is spherical, which allows the stability of the disk. One of the important points is whether the disk can survive the piercing by dark matter units. It appears that the Jeans clusters are so heavy, that only a few million are present, which imply a limited damage to the disk. Some of sets of the Jeans clusters have been observed, in my text I discuss specific cases and also two fields on the sky, one of 180 square degrees, and one towards the Small Magellanic Cloud.

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James T. Dwyer replied on Sep. 10, 2012 @ 01:42 GMT
Theo,

Thanks for responding. If I consider only your proposal as I understand (ignoring my own essay), how could such a stable spherical halo comprised of millions of Jeans clusters survive proximal interactions with other galaxies? There are many observations of spiral galaxies whose disks peripheries have been perturbed by proximal interactions with other galaxies.

Moreover, unlike the merger of galaxy clusters, where intracluster dark matter is thought not to interact, the many millions of discrete objects of mass within a galactic halo composed of Jeans clusters would have to interact and be fully destabilized during the rather common merger of large galaxies. Since, as I understand, the compensatory mass contained within the vast halo structure would be required to prevent expulsion of peripheral galaxy disk objects. It would seem unlikely that any such galaxy structure could be robust enough to survive a disruptive reconfiguration of galaxy mass.

As I understand, It has recently been suggested that the MW halo objects must have been stripped from another galaxy. This would seem to argue against a peripheral halos of compensatory mass comprised of discrete objects of mass. Please see: M. S. Pawlowski , J. Pflamm-Altenburg, P. Kroupa. "The VPOS: a vast polar structure of satellite galaxies, globular clusters and streams around the Milky Way." Monthly Notices of the Royal Astronomical Society 423 2 (June 2012): 1109-1126. doi:10.1111/j.1365-2966.2012.20937.x, arXiv:1204.5176v1.

Thanks again for your consideration. Again, I recommend my brief essay (1419).

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Theo Nieuwenhuizen replied on Oct. 2, 2012 @ 08:15 GMT
Dear Jim, in the essay I have discussed galaxy mergers like Tadpole and Antennae, another example is Mice. It is interesting to look at photographs of them, and to see how young globular clusters are located along the merging paths. That's what we clearly observe from the merging process; what happened with the intertwining halos and disks is a more difficult question, that should follow from dynamical simulation.

By the way, my case has become stronger, since now Ref. [54] is out at arXiv:1210.0489v1. So many Herschel cold clouds have been observed in the Galactic halo towards the Small Magellanic Cloud, that on the average they only need 15,000 Mo to explain all dynamical matter. This is just what should have been achieved by the Jeans instability right after the recombination: break up all the newly formed gas into Jeans clumps of about that mass. If they still exist, they must just constitute the multitude of Herschel cold clouds. There appears to be a lot of consistency in this view point.

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Sergey G Fedosin wrote on Sep. 8, 2012 @ 15:13 GMT
Dear Theodorus,

As an example of possible dark matter particles I describe nuons. These particles are similar at the level of star to the white dwarfs and the Theory of Infinite Hierarchical Nesting of Matter predict their properties. See more in the article: Fedosin S.G. Cosmic Red Shift, Microwave Background, and New Particles. Galilean Electrodynamics, Spring 2012, Vol. 23, Special Issues No. 1, P. 3 - 13.

Sergey Fedosin Essay

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Hoang cao Hai wrote on Oct. 1, 2012 @ 03:20 GMT
Dear Theodorus Maria Nieuwenhuizen

Very interesting to see your essay.

Perhaps all of us are convinced that: the choice of yourself is right!That of course is reasonable.

So may be we should work together to let's the consider clearly defined for the basis foundations theoretical as the most challenging with intellectual of all of us.

Why we do not try to start with a real challenge is very close and are the focus of interest of the human science: it is a matter of mass and grain Higg boson of the standard model.

Knowledge and belief reasoning of you will to express an opinion on this matter:

You have think that: the Mass is the expression of the impact force to material (definition from the ABSOLUTE theory of me) - so no impact force, we do not feel the Higg boson - similar to the case of no weight outside the Earth's atmosphere.

Does there need to be a particle with mass for everything have volume? If so, then why the mass of everything change when moving from the Earth to the Moon? Higg boson is lighter by the Moon's gravity is weaker than of Earth?

The LHC particle accelerator used to "Smashed" until "Ejected" Higg boson, but why only when the "Smashed" can see it,and when off then not see it ?

Can be "locked" Higg particles? so when "released" if we do not force to it by any the Force, how to know that it is "out" or not?

You are should be boldly to give a definition of weight that you think is right for us to enjoy, or oppose my opinion.

Because in the process of research, the value of "failure" or "success" is the similar with science. The purpose of a correct theory be must is without any a wrong point ?

Glad to see from you comments soon,because still have too many of the same problems.

Kind Regards !

Hải.Caohoàng of THE INCORRECT ASSUMPTIONS AND A CORRECT THEORY

August 23, 2012 - 11:51 GMT on this essay contest.

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Sergey G Fedosin wrote on Oct. 2, 2012 @ 07:35 GMT
After studying about 250 essays in this contest, I realize now, how can I assess the level of each submitted work. Accordingly, I rated some essays, including yours.

Cood luck.

Sergey Fedosin

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Member Benjamin F. Dribus wrote on Oct. 3, 2012 @ 20:08 GMT
Dear Theo,

I am particularly grateful for your essay, if only because almost every other essay in this contest involving dark matter is unreservedly negative. Coming mostly from the math side, I am presently somewhat agnostic about dark matter, following Holmes’ observation that “it is a capital mistake to theorize without sufficient evidence.” In such a scenario, one needs evidence from more than one side! Also, you include a splendid level of connection to what is already known. Hence, your submission rates quite high in my opinion. A few more thoughts:

1. I am wondering to what extent the evolution of a particular Jeans cluster, in regard to whether it would form bright globular clusters or become very dark, could be expected to depend on its relative location within the galaxy, and to what extent this would be determined locally? The reason I ask this is because obviously the distribution of dark matter in galaxies is not the same as the distribution of bright matter. I am wondering if the GHD of Jeans clusters predicts quantitatively the distribution seen. Maybe this is implicit somewhere in the paper; for instance, does the reference [40] you cite at the end of section II A give evidence of this?

2. Besides rejecting dark matter entirely, it is also popular to insist that it must involve only one mechanism. It is refreshing to see a submission that avoids this assumption.

3. Thanks for the 75 references. A veritable trove for someone trying to orient himself concerning the subject.

I enjoyed reading your work! Take care,

Ben Dribus

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Theo Nieuwenhuizen replied on Oct. 4, 2012 @ 17:54 GMT
Dear Ben, it is a relief to receive such understanding words. Most of the community can not get dissolved from the mantra from theory, press, blogs etc that the WIMP must exist, that its problems must be solvable and so on, often by just shying away from the existing problems.

1) Jeans clusters should travers the galaxy in a couple of million years, so the present location is not the only discriminator. But those that do no go through the core will differ from those which do.

Ref [40] does not deal with this issue, but you may appreciate to read it, since it answers a lot of issues. It is also on arXiv:1011.2530.

2) From my investigations I come to conclude: the Galaxy does not need non-baryonic DM, its overlooked baryons will do the job.

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Sergey G Fedosin wrote on Oct. 4, 2012 @ 04:32 GMT
If you do not understand why your rating dropped down. As I found ratings in the contest are calculated in the next way. Suppose your rating is
and
was the quantity of people which gave you ratings. Then you have
of points. After it anyone give you
of points so you have
of points and
is the common quantity of the people which gave you ratings. At the same time you will have
of points. From here, if you want to be R2 > R1 there must be:
or
or
In other words if you want to increase rating of anyone you must give him more points
then the participant`s rating
was at the moment you rated him. From here it is seen that in the contest are special rules for ratings. And from here there are misunderstanding of some participants what is happened with their ratings. Moreover since community ratings are hided some participants do not sure how increase ratings of others and gives them maximum 10 points. But in the case the scale from 1 to 10 of points do not work, and some essays are overestimated and some essays are drop down. In my opinion it is a bad problem with this Contest rating process.

Sergey Fedosin

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Renate Quehenberger replied on Oct. 4, 2012 @ 07:50 GMT
Dear Theo,

I see: with Sergey Fedosins creative calculative comment on our bad ratings I am in the very best companionship with YOU.

Nevertheless, my very best wishes and good luck to you!

Renate

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Theo Nieuwenhuizen replied on Oct. 4, 2012 @ 19:20 GMT
Dear Sergei and Renate, thanks for pointing this out to me. I was not bothered by my ratings, I just believe in its Good Case.

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