Dark matter

One of the most contested issues in astrophysics is our understanding of the Universe’s expansion. Adam Riess discusses why there is disagreement and what might resolve it.

Recent observations suggest that dark energy is changing over time. Theorists wonder if dark matter is, too.

Decades of weird experimental results appeared to support the existence of the sterile neutrino, a hypothetical particle that would solve multiple mysteries. But recent experiments have killed hope of finding these phantoms, leaving physicists to wonder what might explain their anomalies.

Pushed down to a certain scale, the laws of physics seem to fall apart. Astrid Eichhorn, a leader in an area of study called asymptotic safety, thinks we just need to push a little further.

Primordial black holes could rewrite our understanding of dark matter and the early universe. A record-breaking detection at the bottom of the Mediterranean Sea has some physicists wondering if we just spotted one.

Tony Tyson’s cameras revealed the universe’s dark contents. Now, with the Rubin Observatory’s 3.2-billion-pixel camera, he’s ready to study dark matter and dark energy in unprecedented detail.

Physicists discovered strange supersolids, constructed new kinds of superconductors, and continued to make the case that the cosmos is far weirder than anyone suspected.

The giant holes in galaxies’ centers shouldn’t be able to merge, yet merge they do. Scientists suggest that an unusual form of dark matter may be the solution.

Physicists have ruled out a mundane explanation for the strange findings of an old Soviet experiment, leaving open the possibility that the results point to a new fundamental particle.