Eigenspectrum Noise Subtraction Methods in Lattice QCD

Understand

We propose a new noise subtraction method, which we call "eigenspectrum subtraction", which uses low eigenmode information to suppress statistical noise at low quark mass.

• This is useful for lattice calculations involving disconnected loops or all-to-all propagators.
• It has significant advantages over perturbative subtraction methods.
• We compare unsubtracted, eigenspectrum and perturbative error bar results for the scalar operator on a small Wilson QCD matrix.