Prof. Dr. John Bulava

The group’s main research activities are computer simulations of the strong nuclear force.
Like van der Waals forces between atoms (but much stronger), the interaction between the protons and neutrons in atomic nuclei emerge from the dynamics of the quarks contained within them. Quantum Chromodynamics (QCD), the quantum field theory describing the behavior of quarks, is however only analytically tractable at distances much smaller than the typical size of ‚hadrons‘ like the proton and neutron.

Large-scale high-performance computer simulations of QCD on a discrete space-time lattice (lattice QCD) are therefore required to study hadron properties and interactions directly from first principles. Of particular interest are scattering processes involving hyperons, which are hadrons containing strange quarks. Hyperon interactions are an ongoing challenge for experiments but are key for understanding the properties of neutron stars and ‚hypernuclei‘ which contain hyperons in addition to protons and neutrons.

Lattice QCD computations of hyperon scattering amplitudes support experimental efforts at GSI and elsewhere, and provide useful input to chiral effective theories. Furthermore, such simulations can serve as thought experiments to study the effect of changes in the fundamental constants of Nature, like the quark masses and number of quark flavors.