Institute for Advanced Study Astrophysics Seminar

The current cosmological model rests on Einstein's theory of general relativity. In order for it to be consistent with large-scale structure data, the existence of cosmologically relevant physical processes need to be postulated: inflation, cold or warm dark matter particles and dark energy. Each of these is not well understood, but assuming the resulting standard mathematical description is a representation of cosmological reality, this representation can be tested in a different regime, namely on the scales of the Local Volume of galaxies down to individual galaxies. It is found that each test which has been designed shows the standard description to fail such that the currently standard model of cosmology is difficult to be upheld. In particular, the Dual-Dwarf-Galaxy Theorem, which must be true in the standard model, is falsified. The arrangement of satellite galaxies in rotating disk-like vast near-polar structures around both, the Milky Way and Andromeda, support this conclusion. As suggested by Milgrom, scale-invariant dynamics may be showing a new direction for the understanding of the astrophysics of galaxies. A successful final description of cosmology is yet to be found though.