New Model-independent Method to Test the Curvature of the Universe
  We propose a new model-independent method to test the cosmic curvature by
comparing the proper distance and transverse comoving distance. Using the
measurements of Hubble parameter $H(z)$ and angular diameter distance $d_A$,
the cosmic curvature parameter $\Omega_K$ is constrained to be $-0.09\pm0.19$,
which is consistent with a flat universe. We also use Monte Carlo simulation to
test the validity and efficiency, and find that our method can give a reliable
and efficient constraint on cosmic curvature. Compared with other
model-independent methods testing the cosmic curvature, our method can avoid
some drawbacks and give a better constraint.
