Magnetohydrodynamic (MHD) turbulence in neutron star (NS) merger remnants can
impact their evolution and multimessenger signatures, complicating the
interpretation of present and future observations. Due to the high Reynolds
numbers and the large computational costs of numerical relativity simulations,
resolving all the relevant scales of the turbulence will be impossible for the
foreseeable future. Here, we adopt a method to include subgrid-scale turbulence
in moderate resolution simulations by extending the large-eddy simulation (LES)
method to general relativity (GR). We calibrate our subgrid turbulence model
with results from very-high-resolution GRMHD simulations, and we use it to
perform NS merger simulations and study the impact of turbulence. We find that
turbulence has a quantitative, but not qualitative impact on the evolution of
NS merger remnants, on their gravitational wave signatures, and on the outflows
generated in binary NS mergers. Our approach provides a viable path to quantify
uncertainties due to turbulence in NS mergers.Comment: 20 pages, 6 figures. Submitted to the special issue "Numerical
Relativity and Gravitational Wave" of Symmetry. Minor changes, matches
accepted versio
