Cosmic Tidal Reconstruction with Halo Fields
  The gravitational coupling between large-scale perturbations and small-scale
perturbations leads to anisotropic distortions of the small-scale matter
distribution. The measured local small-scale power spectrum can thus be used to
infer the large-scale matter distribution. In this paper, we present a new
tidal reconstruction algorithm for reconstructing large-scale modes using the
full three-dimensional tidal shear information. We apply it to simulated dark
matter halo fields and the reconstructed large-scale density field correlates
well with the original matter density field on large scales, improving upon the
previous tidal reconstruction method which only uses two transverse shear
fields. This has profound implications for recovering lost 21~cm radial modes
due to foreground subtraction and constraining primordial non-Gaussianity using
the multi-tracer method with future cosmological surveys.
