  The gravitational coupling between large- and small-scale density
perturbations leads to anisotropic distortions to the local small-scale matter
fluctuations. Such local anisotropic distortions can be used to reconstruct the
large-scale matter distribution, known as tidal reconstruction. In this paper,
we apply the tidal reconstruction methods to simulated galaxies in redshift
space. We find that redshift-space distortions lead to anisotropic
reconstruction results. While the reconstructed radial modes are more noisy
mainly due to the small-scale velocity dispersion, the transverse modes are
still reconstructed with high fidelity, well correlated with the original
large-scale density modes. The bias of the reconstructed field at large scales
shows a simple angular dependence which can be described by a form similar to
the linear redshift-space distortion. The noise power spectrum is nearly
isotropic and scale-independent on large scales. This makes the reconstructed
tides field an ideal tracer for cosmic variance cancellation and multi-tracer
analysis and has profound implications for future 21~cm intensity mapping
surveys.
