Galaxy clustering and dark energy

Abstract

We study the evolution of galaxy clustering in various cosmological models with quintessence. We investigate how the analytical predictions vary with change of dark energy equation of state $w_X$. Comparing these predictions against available data we discuss to what extent the problems of galaxy biasing can be modelled. This will be key in constraining the dark energy equation of state with future galaxy surveys. We use a compilation of various surveys to study the number density and amplitude of galaxy clustering from observations of the local universe at $z \sim 0$ to that of the Lyman break galaxies and Ly-$\alpha$ emitters at $z \sim 4.9$. We find that there is a degeneracy between the dark energy equation of state and the way galaxies populate dark matter haloes; objects are more biased in models with more negative values of dark energy equation of state $w_X$. We conclude that, while future all sky CMB observations will determine cosmological parameters with unprecedented precision, and cross correlation of weak lensing experiments and galaxy surveys will provide a cleaner and accurate picture of bias associated with collapsed objects, the rate of growth of large scale structure in such surveys can potentially constrain the equation of state of dark energy and the potential of the scalar field associated with quintessence. In particular, we show that the abundance and spatial distribution of galaxy clusters at intermediate redshifts strongly depend on the dark energy equation of state. When accurate measurement of galaxy clustering at high-redshit becomes possible, it will provide constraints on dark energy that are independent and complementary to type Ia supernova studies.