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In astronomy, dark matter is an invisible and hypothetical form of matter that does not interact with light or other electromagnetic radiation.Dark matter is implied by gravitational effects which cannot be explained by general relativity unless more matter is present than can be observed.
Dark matter is called ‘dark’ because it’s invisible to us and does not measurably interact with anything other than gravity. It could be interspersed between the atoms that make up the Earth ...
The Planck collaboration version of the ΛCDM model is based on six parameters: baryon density parameter; dark matter density parameter; scalar spectral index; two parameters related to curvature fluctuation amplitude; and the probability that photons from the early universe will be scattered once on route (called reionization optical depth). [18]
In cosmology and physics, cold dark matter (CDM) is a hypothetical type of dark matter.According to the current standard model of cosmology, Lambda-CDM model, approximately 27% of the universe is dark matter and 68% is dark energy, with only a small fraction being the ordinary baryonic matter that composes stars, planets, and living organisms.
Direct detection of dark matter is the science of attempting to directly measure dark matter collisions in Earth-based experiments. Modern astrophysical measurements, such as from the cosmic microwave background , strongly indicate that 85% of the matter content of the universe is unaccounted for. [ 1 ]
Dark matter is a form of matter that neither emits nor absorbs light. Within physics, this behavior is characterized by dark matter not interacting with electromagnetic radiation , hence making it dark and rendering it undetectable via conventional instruments in physics.
The universe may be accelerating, fueled perhaps by a cosmological constant or some other field possessing long range 'repulsive' effects. A model must predict the correct form for the large scale clustering spectrum, [3] account for cosmic microwave background anisotropies on large and intermediate angular scales, and provide agreement with the luminosity distance relation obtained from ...
As "dark matter", baryonic dark matter is undetectable by its emitted radiation, but its presence can be inferred from gravitational effects on visible matter. This form of dark matter is composed of "baryons", heavy subatomic particles such as protons and neutrons and combinations of these, including non-emitting ordinary atoms.