Constraints On The Dark Energy Models From Large Scale Structure Observations

In 1998. the type la supernova observations showed that the Universe was undergoing the epoch of the accelerated expansion. In order to explain this phenomenon, in Einstein’s theory of gravity, we assume that the present Universe is dominated by the dark energy with negative pressure. In 2013, the constraint on the standard model from Planck’s high-precision cosmic-microwave background map has allowed scientists to extract the most refined values yet of the Universe’s ingredients. Normal matter that makes up stars and galaxies contributes just 4.9% of the Universe. Dark matter, which determines the evolution of the Universe, occupies 26.8%, while dark energy, a mysterious force thought to be responsible for accelerating the expansion of the Universe, accounts for 68.3%. Therefore, the dark sectors determine the evolution of the Universe, this idea inspires the physicists to put forward a lot of dark energy models. As for the observational aspect, to break the possible degeneracy of cosmological models, the geometry information is not enough, the dynamical test from the large scale structure information is necessary to discriminate the dark energy models. Here, the redshift space distort ion test will be used to constrain the different dark energy models.First of all. we introduce the research background of the task. research contents, and out-line of the thesis. Subsequently, in the theoretical basics of cosmology, we focus on presenting the background expansion history of the Universe and cosmological scalar perturbation theo-ry. The next section is the introduction of cosmic observations, especially, the redshift space distortion from the large scale structure observations. From Chapters 4 to 6, we show the research contents of this thesis. In Chapter 4. we study an unified dark fluid model with a fast transition in the evolution of equation of state. We discuss the rationality of the model from the theoretical analysis and observational constraints. In Chapter 5. we decompose the uni-fied dark fluid with constant speed of sound into interacting vacuum energy and dark matter, and analyze the growth history of structure by calculating the perturbation equations of dark sectors. We constrain the decomposed dark fluid model by jointing the geometry data sets and redshift space distortion test. In Chapter G. we introduce the interacting model between cold dark matter and dynamical dark energy with a constant equation of state. We deduce the perturbation equations of the energy density and velocity divergence, and analyze the modified growth of structure for the varied interaction rate. We constrain the interaction rate from the large scale structure observation. Finally, the summary and outlook are presented in the last chapter.