SIMDAMA · Strong-interaction matter coupled to electroweak probes and dark matter candidates

For decades, the Standard Model of particle physics has successfullypredicted the outcome of experiments probing the laws of nature on thesmallest distances. Its last missing ingredient, the Higgs particle,was discovered at the Large Hadron Collider at CERN in 2012. A vastexperimental program is now underway to complete its description of weakly interacting particles called neutrinos.For all its successes, the Standard Model does not provide anexplanation for the nature of dark matter, which is thought to account for aquarter of the energy in the universe. This project, based on the`lattice QCD' framework, will enable a more stringent test of theStandard Model, contribute to narrowing down the list ofdark-matter candidate particles, and reduce uncertainties in neutrinodetection.The strong interaction, which binds protons and neutrons together toform atomic nuclei, is described by the sector of the Standard Modelcalled Quantum Chromodynamics (QCD). The complexity of the strong interactionis often the limiting factor in testing the Standard Model and insearching for new fundamental particles and forces. Strong-interactionmatter is also of tremendous intrinsic interest because it exhibitsmany emerging phenomena such as spontaneous symmetry breaking,quantum-relativistic bound states, and a high-temperature `quark-gluonplasma' phase, to name a few. By replacing space and time by alattice, QCD becomes amenable to an ab initio treatment vialarge-scale computer simulations.The subproject of testing `sterile' neutrinos as dark-matterconstituents depends on understanding aspects of hot QCD matter, sincethey would have been produced in the early, hot universe. This goal isthus connected to present-day heavy-ion collision experiments, wheretiny droplets of hot QCD matter are produced in the laboratory.