Global InformationDark matter information
What is dark matter? How was it generated?
| Part of a series on |
| Physical cosmology |
|---|
 |
|
|
In astronomy, dark matter is a hypothetical form of matter that appears not to interact with light or the electromagnetic field. Dark matter is implied by gravitational effects which cannot be explained by general relativity unless more matter is present than can be seen. Such effects occur in the context of formation and evolution of galaxies,[1] gravitational lensing,[2] the observable universe's current structure, mass position in galactic collisions,[3] the motion of galaxies within galaxy clusters, and cosmic microwave background anisotropies.
In the standard lambda-CDM model of cosmology, the mass–energy content of the universe is 5% ordinary matter, 26.8% dark matter, and 68.2% a form of energy known as dark energy.[4][5][6][7] Thus, dark matter constitutes 85%[a] of the total mass, while dark energy and dark matter constitute 95% of the total mass–energy content.[8][9][10][11]
Dark matter is not known to interact with ordinary baryonic matter and radiation except through gravity,[b] making it difficult to detect in the laboratory. The most prevalent explanation is that dark matter is some as-yet-undiscovered subatomic particle,[c] such as weakly interacting massive particles (WIMPs) or axions.[12] The other main possibility is that dark matter is composed of primordial black holes.[13][14][15]
Dark matter is classified as "cold", "warm", or "hot" according to its velocity (more precisely, its free streaming length). Recent models have favored a cold dark matter scenario, in which structures emerge by the gradual accumulation of particles.
Although the astrophysics community generally accepts dark matter's existence,[16] a minority of astrophysicists, intrigued by specific observations that are not well-explained by ordinary dark matter, argue for various modifications of the standard laws of general relativity. These include modified Newtonian dynamics, tensor–vector–scalar gravity, or entropic gravity. So far none of the proposed modified gravity theories can successfully describe every piece of observational evidence at the same time, suggesting that even if gravity has to be modified, some form of dark matter will still be required.[17]
- ^ Siegfried, T. (5 July 1999). "Hidden space dimensions may permit parallel universes, explain cosmic mysteries". The Dallas Morning News.
- ^ Trimble, V. (1987). "Existence and nature of dark matter in the universe" (PDF). Annual Review of Astronomy and Astrophysics. 25: 425–472. Bibcode:1987ARA&A..25..425T. doi:10.1146/annurev.aa.25.090187.002233. S2CID 123199266. Archived (PDF) from the original on 18 July 2018.
- ^ "A history of dark matter". 2017.
- ^ "Planck Mission Brings Universe into Sharp Focus". NASA Mission Pages. 21 March 2013. Archived from the original on 12 November 2020. Retrieved 1 May 2016.
- ^ "Dark Energy, Dark Matter". NASA Science: Astrophysics. 5 June 2015.
- ^ Ade, P. A. R.; Aghanim, N.; Armitage-Caplan, C.; et al. (Planck Collaboration) (22 March 2013). "Planck 2013 results. I. Overview of products and scientific results – Table 9". Astronomy and Astrophysics. 1303: 5062. arXiv:1303.5062. Bibcode:2014A&A...571A...1P. doi:10.1051/0004-6361/201321529. S2CID 218716838.
- ^ Francis, Matthew (22 March 2013). "First Planck results: the Universe is still weird and interesting". Ars Technica.
- ^ "Planck captures portrait of the young Universe, revealing earliest light". University of Cambridge. 21 March 2013. Retrieved 21 March 2013.
- ^ Carroll, Sean (2007). Dark Matter, Dark Energy: The dark side of the universe. The Teaching Company. Guidebook Part 2 p. 46.
... dark matter: An invisible, essentially collisionless component of matter that makes up about 25 percent of the energy density of the universe ... it's a different kind of particle... something not yet observed in the laboratory ...
- ^ Ferris, Timothy (January 2015). "Dark matter". Hidden cosmos. National Geographic Magazine. Archived from the original on 25 December 2014. Retrieved 10 June 2015.
- ^ Jarosik, N.; et al. (2011). "Seven-year Wilson microwave anisotropy probe (WMAP) observations: Sky maps, systematic errors, and basic results". Astrophysical Journal Supplement. 192 (2): 14. arXiv:1001.4744. Bibcode:2011ApJS..192...14J. doi:10.1088/0067-0049/192/2/14. S2CID 46171526.
- ^ Timmer, John (21 April 2023). "No WIMPS! Heavy particles don't explain gravitational lensing oddities". Ars Technica. Retrieved 21 June 2023.
- ^ Carr, B. J.; Clesse, S.; García-Bellido, J.; Hawkins, M. R. S.; Kühnel, F. (26 February 2024). "Observational evidence for primordial black holes: A positivist perspective". Physics Reports. 1054: 1–68. arXiv:2306.03903. Bibcode:2024PhR..1054....1C. doi:10.1016/j.physrep.2023.11.005. ISSN 0370-1573. See Figure 39.
- ^ Bird, Simeon; Albert, Andrea; Dawson, Will; Ali-Haïmoud, Yacine; Coogan, Adam; Drlica-Wagner, Alex; Feng, Qi; Inman, Derek; Inomata, Keisuke; Kovetz, Ely; Kusenko, Alexander; Lehmann, Benjamin V.; Muñoz, Julian B.; Singh, Rajeev; Takhistov, Volodymyr; Tsai, Yu-Dai (1 August 2023). "Primordial black hole dark matter". Physics of the Dark Universe. 41: 101231. arXiv:2203.08967. doi:10.1016/j.dark.2023.101231. ISSN 2212-6864. S2CID 247518939.
- ^ Cite error: The named reference
Carrwas invoked but never defined (see the help page). - ^ Hossenfelder, Sabine; McGaugh, Stacy S. (August 2018). "Is dark matter real?". Scientific American. 319 (2): 36–43. Bibcode:2018SciAm.319b..36H. doi:10.1038/scientificamerican0818-36. PMID 30020902. S2CID 51697421.
Right now a few dozens of scientists are studying modified gravity, whereas several thousand are looking for particle dark matter.
- ^ Cite error: The named reference
CarrollTrialoguewas invoked but never defined (see the help page).
Cite error: There are <ref group=lower-alpha> tags or {{efn}} templates on this page, but the references will not show without a {{reflist|group=lower-alpha}} template or {{notelist}} template (see the help page).