Browse Physics

Theories of dark matter interacting with a light force carrier, proposed to explain the excess of high-energy positrons in the cosmic rays, turn out to have problems.

What are the uncertainties in determining how long ago nucleosynthesis of heavy elements occurred in astrophysical bodies?

New data are inconsistent with previous measurements that showed an unexpected excess of diffuse gamma-ray emission in the Galaxy.

Detectors buried beneath the Antarctic ice place stringent limits on the presence of dark matter particles, called neutralinos, in the sun.

Two antimatter measurements performed by the PAMELA experiment appear to lead to conflicting results. Now, theorists are exploring the extent to which these measurements can be reconciled.

Interactions between dark matter particles may explain unusual matter-antimatter production rates in the universe.

Mounting evidence seems to rule out weakly interacting massive particles (WIMPs ) as the source of a so-far unexplained signal in the DAMA/LIBRA experiments.

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.