Understand
Over the past few decades, a consensus picture has emerged in which roughly a quarter of the universe consists of dark matter.
- I begin with a review of the observational evidence for the existence of dark matter: rotation curves of galaxies, gravitational lensing measurements, hot gas in clusters, galaxy formation, primordial nucleosynthesis and cosmic microwave background observations.
- Then I discuss a number of anomalous signals in a variety of data sets that may point to discovery, though all of them are controversial.
- The annual modulation in the DAMA detector and/or the gamma-ray excess seen in the Fermi Gamma Ray Space Telescope from the Galactic Center could be due to WIMPs; a 3.5 keV X-ray line from multiple sources could be due to sterile neutrinos; or the 511 keV line in INTEGRAL data could be due to MeV dark matter.