  Lattice QCD simulations tend to get stuck in a single topological sector at
fine lattice spacing, or when using chirally symmetric quarks. In such cases
computed observables differ from their full QCD counterparts by finite size
effects, which need to be understood on a quantitative level. We discuss
extensions of existing relations from the literature between correlation
functions at fixed topology and hadron masses at unfixed topology. Particular
focus is put on disentangling positive and negative parity states, which mix,
when the topological charge is fixed. We also present numerical results for
SU(2) Yang-Mills Theory.
