It's filled with trillions of galaxies, clustered together in a great cosmic web, bathed in the Big Bang's leftover radiation at a minuscule temperature of just 2.73 K. But the biggest surprise is that the particles and fields we know of are insufficient, on their own, to explain the Universe we see.
Constraints on the total matter content (normal+dark, x-axis) and dark energy density (y-axis) from three independent sources: supernovae, the CMB (cosmic microwave background) and BAO (which is a wiggly feature seen in the correlations of large-scale structure).
NASA, ESA, C. Faure (Zentrum für Astronomie, University of Heidelberg) and J.P. Kneib (Laboratoire d'Astrophysique de Marseille)The evidence that exists for dark matter is overwhelming and comes in an enormous suite, but suffers from a distinct drawback from the ideal scenario: it's all indirect.
The relic signatures imprinted on our Universe from an inflationary state before the hot Big Bang give us a unique way to test our cosmic history, subject to the same fundamental limitations that all frameworks possess.
You need to devise a way to retain those relics, which is an extra burden on your theory; the new paper claiming to create dark matter before the Big Bang models this as a new fundamental scalar field in the Universe.
E. Siegel, with images derived from ESA/Planck and the DoE/NASA/ NSF interagency task force on CMB researchBut most of the models of dark matter involve hypothesizing a mechanism of particle creation that occurs after the Big Bang.
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- The Mystery Of The Universe Before The Big Bang Remains UnsolvedV Herald
- Primordial Black Holes Might Have Created A Part Of The Existing Dark MatterDual Dove
- AI probes dark matter in the UniverseTech Explorist