Lattice QCD with open boundary conditions and twisted-mass reweighting

Understand

Lattice QCD simulations at small lattice spacings and quark masses close to their physical values are technically challenging.

• In particular, the simulations can get trapped in the topological charge sectors of field space or may run into instabilities triggered by accidental near-zero modes of the lattice Dirac operator.
• As already noted in ref.
• [1], the first problem is bypassed if open boundary conditions are imposed in the time direction, while the second can potentially be overcome through twisted-mass determinant reweighting [2].