Cosmology

Physicists have measured the lifetime of a free neutron more precisely than ever before. This breakthrough "bathtub" experiment helps probe the fringes of the Standard Model of particle physics, and mysteries like dark matter and the early universe.

Dark matter should be all around us, but the stuff is frustratingly elusive. Now physicists at NIST have developed a new sensor that could help us detect certain hypothetical dark matter particles, using a two-dimensional quantum crystal.

Planets rotate, stars rotate, galaxies and galaxy clusters all rotate. Astronomers have now discovered evidence that larger scale structures of the universe also rotate – mind-bogglingly gigantic filaments that pipe galaxies around the cosmos.

There’s invisible, undetectable stuff all around us, and we call it dark matter. There’s plenty of evidence that this stuff is very real, but what exactly is dark matter? How do we know it’s there? And how are scientists looking for it?

The expansion of the universe is accelerating, and current models call the driving force dark energy. But perhaps this placeholder doesn’t exist – a new study has found that dark matter could produce the same effect if it had some form of magnetism.

Scientists at CERN have used lasers to cool down antimatter for the first time. The milestone could help unlock some of the secrets of this weird substance, including why it didn’t annihilate the universe soon after the Big Bang.

In January scientists reported the detection of very low-frequency gravitational waves. Now astrophysicists have investigated two possible sources – the universe cooling down after the Big Bang, and a field of particles that could be dark matter.

Astronomers have detected a strange signal coming from neutron stars that could be a new elementary particle. An unexplained excess of X-rays hints at axions, hypothetical “ghost” particles that could solve several long-standing physics puzzles.

The Super-Kamiokande neutrino observatory in Japan has received an upgrade. A rare-earth element called gadolinium has been added to the water in the facility, which will make it more sensitive to neutrinos from more distant and ancient supernovae.

The universe will most likely end by slowly fading to black over trillions of years. Now a theoretical physicist has calculated the last interesting event that will ever happen: the explosions of stars called black dwarfs, which don’t even exist yet.

The universe likes to play coy about its age, but we have a pretty good idea of the range. Now, a series of new studies has investigated the question using different methods, and have reached different answers, separated by more than a billion years.

One of the core components of cosmology is the understanding that the universe is expanding evenly in all directions. But new X-ray observations now suggest that this may not be the case after all – certain areas may be expanding faster than others.