Improving cosmological parameter estimation with the future 21 cm
  observation from SKA
  Future observations of 21 cm emission from neutral hydrogen survey will
become a promising approach to probe the large scale structure of Universe. In
this paper, we investigate the impacts of Square Kilometer Array (SKA) 21 cm
observation on the estimation of cosmological parameters. We use the simulated
data of the baryonic acoustic oscillation (BAO) measurements based on the
future SKA experiment with the intensity mapping (IM) technique to do the
analysis. For the current observations, we use the latest cosmic microwave
background (CMB) observation from {\it Planck} 2018, the optical BAO
measurements, and the Type Ia supernovae (SN) observation (Pantheon
compilation). We find that the SKA mock data could break the degeneracy between
the matter density and the Hubble constant, further improving the cosmological
constraints to a great extent. We also find that the constraint on the equation
of state parameters of dark energy could be significantly improved by including
the SKA mock data into the cosmological global fit.
