Browse Physics

The first results from the space-borne Alpha Magnetic Spectrometer confirm an unexplained excess of high-energy positrons in Earth-bound cosmic rays.

The IceCube neutrino telescope reports its most extensive search for neutrinos produced by dark matter annihilations in the Sun.

Invisible sheetlike structures, which might pervade space and contribute to dark matter or dark energy, could be revealed as they pass by Earth-based detectors.

Three major drawbacks to the ΛCDM dark matter model of the universe may be ameliorated if a proposed particle couples to dark matter and to neutrinos.

A new analysis shows that it is possible to look for dark-matter particles with mass far below 1 giga-electron-volt by using atomic ionization.

The dominance of matter over antimatter is further extended with a balloon experiment ruling out the presence of antihelium in cosmic rays at the lowest level to date.

The breaking of charge-parity symmetry at lower temperatures than expected in the initial stages of the big bang could explain the abundance of matter over antimatter in the universe.

The observation of nearby galaxies provides new and stronger limits on dark matter.

A satellite currently hunting for planets around distant stars could potentially spot black holes that some theories take for the missing dark matter.

The spatial distribution of dark matter around different types of galaxies can be explained if its particles scatter one another, theorist suggest, but only if the interaction has a finite range.

The IceCube neutrino detector buried in the Antarctic ice reports that high-energy neutrinos, expected from gamma-ray bursts, have yet to be observed.

The idea of inflation–an exponential expansion of the universe in its first moments–was published in 1981, in a paper that imported new ideas from particle physics into theoretical cosmology.

A set of proposed relations among observable quantities may allow strong tests of whether a rapid expansion of the very early universe produced the seeds of the large-scale structure we see today.

A hypothetical particle might explain both the existence of dark matter and the prevalence of matter over antimatter.

Results from the first three weeks of running the XENON100 experiment show its promise as a sensitive detector of particle dark matter in the form of WIMPs.

New data from the PAMELA satellite on the abundance of antiprotons in cosmic rays still leave the door open for dark matter theories, as well as other explanations.

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.

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

Relic neutrinos from the big bang have come from a region of the universe much nearer than the famous cosmic microwaves, even though they are older.