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The collaboration has observed a new kind of “pentaquark” and the first-ever pair of “tetraquarks” The international LHCb collaboration at the Large Hadron Collider (LHC) has observed three never-before-seen particles: a new kind of “pentaquark” and the first-ever pair of “tetraquarks”, which includes a new type of tetraquark. The findings, presented today at a CERN seminar, add three new exotic members to the growing list of new hadrons found at the LHC. They will help physicists better understand how quarks bind together into these composite particles. Quarks are elementary particles and come in six flavours: up, down, charm, strange, top...

Because perturbation theory doesn’t work, it is very hard to predict the consequences of the strong force. One thing we do know is that the binding energy of the strong force which holds the quarks together inside them is responsible for almost all of the mass of protons and neutrons, and hence almost all of the mass of you. Calculations on supercomputers (such as the DiRAC facility in the UK) use “lattice” methods to make calculations when perturbation theory doesn’t work. These involve approximating the space-time continuum by a lattice of discrete points and events; they are now able to...