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Can Geometric Test Probe the Cosmic Equation of State ?

Kazuhiro Yamamoto·Hiroaki Nishioka
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Abstract

Feasibility of the geometric test as a probe of the cosmic equation of state of the dark energy is discussed assuming the future 2dF QSO sample. We examine 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 on 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 confusion that a signal from the cosmological model can be confused with that from a stochastic character of the bias.

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Kazuhiro Yamamoto, Hiroaki Nishioka. 2001-01-11. Can Geometric Test Probe the Cosmic Equation of State ?. https://doi.org/10.1086/319135

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