Self-interacting dark matter

In astrophysics, self-interacting dark matter (SIDM) is a hypothetical form of dark matter consisting of particles with strongself-interactions. This type of dark matter was postulated in 2000 to resolve a number of conflicts between observations and simulations (of collisionless cold dark matter) on the galactic scale and smaller. It was also used to explain the 2015 observations of ESO 146-5 the core of the Abell 3827 galaxy cluster.

Self-interacting dark matter has also been postulated as an explanation for the DAMA annual modulation signal.

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