Galaxies as simple dynamical systems: observational data disfavor dark matter and stochastic star formation

  title={Galaxies as simple dynamical systems: observational data disfavor dark matter and stochastic star formation},
  author={Pavel Kroupa},
  journal={Canadian Journal of Physics},
  • P. Kroupa
  • Published 2014
  • Physics
  • Canadian Journal of Physics
According to modern theory, galactic evolution is driven by the dynamics of dark matter and stochastic star formation, but galaxies are observed to be simple systems. The existence of dark matter particles is a key hypothesis in present-day cosmology and galactic dynamics. Given the large body of high-quality work within the standard model of cosmology (SMoC), the validity of this hypothesis is challenged significantly by two independent arguments: (i) The dual dwarf galaxy theorem must be true… Expand
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The Dark Matter Crisis: Falsification of the Current Standard Model of Cosmology
  • P. Kroupa
  • Physics
  • Publications of the Astronomical Society of Australia
  • 2012
Abstract The current standard model of cosmology (SMoC) requires The Dual Dwarf Galaxy Theorem to be true according to which two types of dwarf galaxies must exist: primordial dark-matter (DM)Expand
Galaxies appear simpler than expected
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The spatial distribution of galactic satellites in the Λ cold dark matter cosmology
We investigate the spatial distribution of galactic satellites in high-resolution simulations of structure formation in the Λ cold dark matter (ΛCDM) model: the Aquarius dark matter simulations ofExpand
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We present cosmological hydrodynamical simulations of eight Milky Way-sized haloes that have been previously studied with dark matter only in the Aquarius project. For the first time, we employ theExpand
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Within the cold dark matter (CDM) framework tidal dwarf galaxies (TDGs) cannot contain dark matter, so the recent results by Bournaud et al. (2007, Science, 316, 1166) that 3 rotating TDGs do showExpand
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Neutral hydrogen line observations of the extended rotation curves of spiral galaxies imply that there exist significant discrepancies between the luminous and dynamical mass beyond the brightExpand
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The formation of disc galaxies in a ΛCDM universe
We study the formation of disc galaxies in a fully cosmological framework using adaptive mesh refinement simulations. We perform an extensive parameter study of the main subgrid processes thatExpand