Particle physics

The movements of the Sun, Moon and stars have long been used to keep track of time, and now engineers from the University of Tokyo have proposed a new way to use the cosmos to precisely track time, using showers of particles from cosmic rays.

The Large Hadron Collider (LHC), the largest and most powerful particle accelerator ever built, is ready to renter service after a three-year overhaul and refit. On April 22, two proton beams were sent around the the 27-kilometer-long ring.

A collaboration of physicists has made the most precise measurement of the mass of the W boson. The new measurement of this key particle differs drastically from the Standard Model's predictions– and it may unravel physics as we know it.

The universe is governed by two sets of seemingly incompatible laws of physics – classical and quantum physics. MIT physicists have now observed the moment atoms switch from one to the other, as they form intriguing “quantum tornadoes.”

Physicists at CERN have discovered that antimatter falls down. It sounds obvious, but scientists hadn’t yet been able to confirm that it responds to gravity in the same way as regular matter does. A new experiment provides the best answer so far.

CERN physicists have measured the life of the Higgs boson with greater accuracy than ever before. Since the legendary particle only lives for a tiny fraction a second, the scientists came up with a creative workaround to calculate the new figure.

Fermilab physicists have developed a next-generation magnet that can generate a magnetic field with great efficiency, and used it to demonstrate what they describe as the world’s fastest ramping rates for particle accelerator magnets.

A huge range of dark matter suspects are being investigated. In a new study, astronomers have searched for clouds of hypothetical ultralight particles that could congregate around black holes, and reveal themselves by sending out gravitational waves.

Physicists have detected “ghost particles” in the Large Hadron Collider for the first time. An experiment called FASER picked up signals of neutrinos being produced in particle collisions, which can help scientists better understand key physics.

How did the universe end up with exactly the amount of dark matter needed? A new model suggests dark matter particles in the early universe converted regular matter into dark matter exponentially, before being slowed by the expansion of the universe.

Normal matter has an “evil twin” that annihilates on contact, and despite decades of study antimatter remains very mysterious. So what actually is it? Where is it? Why is it important to understand? And why hasn’t it already destroyed the universe?

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.