Can the geometric test probe the cosmic equation of state?

The feasibility of the geometric test as a probe of the cosmic equation of state of the dark energy is discussed assuming the future Two Degree Field QSO sample. We examine the sensitivity of the QSO two-point correlation functions, which are theoretically computed incorporating the light cone effect and the redshift distortions, as well as the nonlinear effect, to a bias model whose evolution is phenomenologically parameterized. It is shown that the correlation functions are sensitive to a mean amplitude of the bias and not to the speed of the redshift evolution. We will also demonstrate that an optimistic geometric test could suffer from the possibility that a signal from the cosmological model can be confused with that from a stochastic character of the bias.