Constraining cosmological anisotropy using standard sirens from the next generation of gravitational wave detectors

Measurements of the accelerating expansion of the Universe have resulted in a significant tension in values of the Hubble-Lemaître parameter H, suggesting an issue with the standard cosmological model. One method to investigate this tension is to allow for cosmological anisotropies, instead of assuming isotropy as in the standard cosmological model. Anisotropies have been suggested by studies of a dipole in H via standard candle supernovae, anisotropic quasar populations, unusual features in the cosmic microwave background, and a dipole in the fine-structure constant. The current work assesses the potential of the next-generation of ground-based gravitational wave detectors to study anisotropic cosmology via the luminosity distances of standard sirens. Projected constraints on a dipole anisotropy are assessed using two sets of 100,000 simulated binary neutron star mergers for six networks of current and next generation gravitational wave detectors. A non-Friedmann-Lemaître–Robertson–Walker expansion is used for the luminosity distance model, allowing the simulations to constrain non-standard cosmologies. The potential constraints of these simulated datasets will be presented.