Questions about astrophysical observations, experimental searches, and theoretical models related to dark matter and its quanta.
The astrophysical dark matter outweighs our usual ("baryonic") matter 5:1. There are a wealth of independent cosmological and astrophysical observations that all support this conclusion; the most important examples are
- observations of the Cosmic Microwave Background
- galaxy clusters and
- the rotation curves of galaxies.
The nature of dark matter is unknown, and significant experimental effort is devoted to identifying the quanta of dark matter. Most notably this includes
- precision gravitational observations of astrophysical systems
- so-called "indirect" astronomical searches for dark matter annihilation or decay products
- searches at colliders for particles that might be related to dark matter and
- the so-called "direct" searches for scattering or other interactions of dark matter with laboratory-scale experiments.
Notable hypotheses for dark matter quanta include Axions, WIMPs, and sterile neutrinos. Questions related to these observations, experimental methods, or theoretical models should be tagged with dark-matter.