André de Gouvêa explains why neutrino masses imply the existence of new fundamental fields. Misfits Massive neutrinos are not part of the Standard Model. Credit: Symmetry After all these years, ...

Marek Karliner and Jonathan Rosner ask what makes tetraquarks and pentaquarks tick, revealing them to be at times exotic compact states, at times hadronic molecules and at times both – with much still ...

Patrick Koppenburg and Marco Pappagallo survey the 23 exotic hadrons discovered at the LHC so far. Twenty-three exotic states Five pentaquarks and 18 tetraquarks have been discovered so far at the LHC ...

Vivian Poulin asks if the tension between a direct measurement of the Hubble constant and constraints from the early universe could be resolved by new physics. On large scales the dominant motion of ...

The development at CERN of magnesium diboride cables and other advanced superconducting systems for the High-Luminosity LHC is also driving applications beyond fundamental research, describes Amalia ...

Before the discovery of quarks, Nicola Cabibbo arrived at the correct formulation of the mechanism responsible for quark mixing. Luciano Maiani, Guido Martinelli and Giorgio Parisi recount Cabibbo’s ...

Jochen Klein and Marco van Leeuwen describe the physics motivation, detector concept and projected performance of a next-generation heavy-ion programme for LHC Runs 5 and 6. Brand new ALICE 3 is built ...

The Courier matched photos from CERN’s first 25 years to current experts and asked them to reflect on how much has changed across 70 years of science. The past seven decades have seen remarkable ...

Andrzej Buras explains how two rare kaon decays and four rare B-meson decays will soon probe for new physics beyond the reach of direct searches at colliders. No trivial pursuit Six ultra-rare decays ...

Geared for discovery more so than delicacy, the LHC is defying expectations by rivalling lepton colliders for precision. Guillelmo Gomez-Ceballos and Jan Kretzschmar identify five measurements of the ...

Louis Lyons traces the origins of the “five sigma” criterion in particle physics, and asks whether it remains a relevant marker for claiming the discovery of new physics. Disentanglement A Jackson ...

With a new measurement imminent, the Courier explores the experimental results and theoretical calculations used to predict ‘muon g-2’ – one of particle physics’ most precisely known quantities and ...