New results from the Fermi Gamma-Ray Space Telescope, the most precise to date in the energy range to , should help resolve whether cosmic rays composed of the lightest charged particles, i.e., electrons and positrons, come from dark matter or some other astrophysical source.
Physics2, 10 (2009) – Published February 2, 2009
Many cosmologists believe that antiprotons in cosmic rays come from the annihilation of dark matter. Data from the PAMELA experiment on board a Russian satellite provide an important test of this possibility.
At the current time, we cannot tell if Einstein’s cosmological constant—or some other theory—is the correct description for dark energy in the Universe. A proposed measure based on existing data may help us to better distinguish these ideas.