  Active fluids, which are driven at the microscale by non-conservative forces,
are known to exhibit novel transport phenomena due to the breaking of time
reversal symmetry. Recently, Epstein and Mandadapu [arXiv:1907.10041] obtained
Green-Kubo relations for the full set of viscous coefficients governing
isotropic chiral active fluids, including the so-called odd viscosity, invoking
Onsager's regression hypothesis for the decay of fluctuations in active
non-equilibrium steady states. In this Communication, we test these Green-Kubo
relations using molecular dynamics simulations of a canonical model system
consisting of actively torqued dumbbells. We find the resulting odd and shear
viscosity values from the Green-Kubo relations to be in good agreement with
values measured independently through non-equilibrium molecular dynamics (NEMD)
flow simulations. This provides a test of the Green-Kubo relations, and lends
support to the application of the Onsager regression hypothesis in relation to
viscous behaviors of active matter systems.
