Particle Physics

Cosmic Microwave Background Stage 4, a top-priority project for U.S. astrophysics, was designed to make breakthrough observations of the universe’s very earliest moments. Now the U.S. government says it can’t currently support the project’s construction at the South Pole

Every now and then, tiny particles of antimatter strike Earth from cosmic parts unknown. A new balloon-borne experiment launching this spring may at last find their source

Domain walls, long a divisive topic in physics, may be ideal explanations for some bizarre cosmic quirks

New discoveries demystify the bizarre force that binds atomic nuclei together

The Nobel Prize-winning theorist’s prediction of the Higgs boson sparked a half-century quest of discovery that reshaped physics—and our understanding of the universe

A new generation of lab experiments is aiming to weigh neutrinos with astonishing accuracy

Several branches of modern physics, including quantum theory and cosmology, suggest our universe may be just one of many

Electron tornadoes that mimic “magnetic monopoles” emerge from specks of rust

Researchers have created ultraheavy versions of elements that have never existed before on Earth

Physicists seek the dividing line between the quantum world and the classical one

Scientists are ramping up production of the isotope actinium 225, which could help treat prostate cancer

A feasibility study on CERN’s Future Circular Collider identifies where and how the machine could be built—but its construction is far from assured