Pavel Kroupa: The Dark Matter Crisis

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Dark Matter Problems, Cosmology and Progress: a personal account


Falsification of the dark-matter hypothesis on You Tube:

Heidelberg Joint Colloquium: 12th Nov. 2013 The vast polar structures around the Milky Way and Andromeda, and the implications thereof for fundamental physics.

Bethe Colloquium: Dark Matter - a Debate between Pavel Kroupa and Simon White at the Bethe Forum of the University of Bonn on 18th Nov. 2010:
The two presentations.
The debate .
The final debate afterwards .

A TV interview with "SWR1 Leute" on the above issues (in German).

[I also research other problems, for example the formation and evolution of star clusters: an interview in Grenada, Spain .]

See also the published papers:
Local-Group tests of dark-matter concordance cosmology. Towards a new paradigm for structure formation y [Kroupa et al., 2010],
The Dark Matter Crisis: Falsification of the Current Standard Model of Cosmology [Kroupa, 2012],
Lessons from the Local Group (and beyond) on dark matter [Kroupa, 2014],
Galaxies as simple dynamical systems: observational data disfavor dark matter and stochastic star formation [Kroupa, 2015].
The observed spatial distribution of matter on scales ranging from 100kpc to 1Gpc is inconsistent with the standard dark-matter-based cosmological models [Kroupa, 2016].


Phantom of Ramses (PoR) code for galaxy formation and evolution in Milgromian dynamics/MOND:

With a small grant from the Rectorate of the University of Bonn PK received in 2013, Fabian Lueghausen (in collaboration with Benoit Famaey and Pavel Kroupa) was able to develop in 2014 and 2015 a patch to Romain Teyssier's RAMSES code to allow dark-matter-free high-resolution simulations of galaxy formation and evolution.
The Lueghausen, Famaey & Kroupa 2015 Phantom of Ramses (PoR) code is a patch to RAMSES. By default the patch comes with the RAMSES code whenever it is downloaded.

Independently of PoR, Candlish, Smith & Fellhauer (2015) developed RAYMOND which is also a RAMSES-based Milgromian-dynamics simulation code.


Wrong claims that standard-cosmological LCDM models can account for the observed satellite distributions:

Maji, Zhu, Marinacci & Li (2017a) and Maji, Zhu, Marinacci & Li (2017b) claim that the Disk of Satellites (DoS) around the Milky Way may be a misrepresentation of the data. These two manuscripts are based on false historical claims, procedural errors and incorrect treatment of data, as shown by Pawlowski et al. 2017.

The Bahl & Baumgardt 2014 claim that the Andromeda great plane of satellites readily occurs in LCDM models is wrong, as shown by Ibata et al. 2014 and by Pawlowski et al. 2014 , who also discuss two other recent flawed claims that the observed satellite populations are consistent with LCDM models.

The Cautun, Wang, Frenk & Sawala 2015 claim that the anti-correlation of satellite galaxies observed around many host galaxies (discovered by Ibata et al. 2014) does not exist is wrong, as shown by Ibata et al. 2015.

Close scrutiny of such claims made by the standard-cosmology teams have until now always yielded flaws in the applied analysis. Noteworthy is that some of these claims (notably Maji et al.) are published on the arXiv before being refereed. With false claims being made, these authors appear to purposefully distort the scientific process. This damages science, because many readers do not have the knowledge of the subject, rely on the statements made by the authors, and the rigorous mathematical details may often be too involved for quick understanding.

Is this behaviour a result of over-motivation to demonstrate that LCDM works? Is it a desire to appear main-stream in the competition for funds, or for vying for some employment possibility? If this strategy works, then this part of the cosmological community has a serious problem in remaining to be viewed as a scientific establishment.

David Merritt provides a critical discussion of the present-day status of cosmological research in "Cosmology and Convention" ( Merritt, 2017). This situation in cosmology is part of a very major problem in fundamental physics research as elaborated in "The trouble with physics" by Lee Smolin 2006.

In the above Ibata et al. 2015 rebuttal, the authors write in their abstract: "All these unexpected correlations strongly suggest that a substantial fraction of satellite galaxies are causally-linked in their formation and evolution.", in agreement with the conclusions reached independently elsewhere that most, if not all, dSph and UFD satellites are old tidal dwarf galaxies without particle dark matter (2012a, 2012b and 2015; see also 1997).


Links to some of my relevant research papers and the German "Spektrum der Wissenschaft" article (free of charge, "kostenfrei"):



Links to related Nature and a few other papers dealing with issues relevant to the Dark Matter Problem:



Links to reviews on Milgromian dynamics/MOND:



The Dark Matter Crisis main page on SciLogs

We document on the web, as best we can and within our spare time, the paradigm change away from the concordance or standard cold or warm dark matter based cosmological models (the LCDM or LWDM models) towards a new understanding of cosmological physics.

SciLogs contents with links:

(by Marcel Pawlowski and Pavel Kroupa)

  • Link to unrelated comments to the above contributions is here (begun in Nov.2013).





    Prof. Dr. Pavel Kroupa (University of Bonn; https://www.astro.uni-bonn.de/~pavel/ )


    Pavel Kroupa and Mordehai Milgrom at MGADS, Strasbourg, 29.06.2010.




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