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Self-interacting dark matter

If the self-interacting dark matter is in hydrostatic equilibrium, its pressure and density follow:

${\displaystyle \nabla P_{\chi }/\rho _{\chi }=\nabla \Phi _{\rm {tot}}=\nabla (\Phi _{\chi }+\Phi _{b})}$

where ${\displaystyle \Phi _{\chi }}$ and ${\displaystyle \Phi _{b}}$ are the gravitational potential of the dark matter and a baryon respectively. The equation naturally correlates the dark matter distribution to that of the baryonic matter distribution. With this correlation, the self-interacting dark matter can explain phenomena such as the Tully–Fisher relation.

Self-interacting dark matter has also been postulated as an explanation for the DAMA annual modulation signal.^[6][7][8] Moreover, it is shown that it can serve the seed of supermassive black holes at high redshift.^[9] SIDM may have originated in a so-called "Dark Big Bang".^[10]

See also[edit]

• MACS J0025.4-1222, astronomical observations that constrain DM self-interaction
• ESO 146-5, the core of Abell 3827 that was claimed as the first evidence of SIDM
• Strongly interacting massive particle (SIMP), proposed to explain cosmic ray data
• Lambda-CDM model

References[edit]

Further reading[edit]

• Bertone, Gianfranco (2010). Particle Dark Matter: Observations, Models and Searches. Cambridge University Press. p. 762. Bibcode:2010pdmo.book.....B. ISBN 978-0-521-76368-4.
• Musser, George (May 2000). "What's the Matter?". Scientific American. 282 (5): 24. Bibcode:2000SciAm.282e..24M. doi:10.1038/scientificamerican0500-24.
• Lawrence, Krauss (2000). Quintessence: The Search for Missing Mass in the Universe. Basic Books. p. 384. ISBN 978-0465037414.