On The Evolution Of Generalized Ghost Dark Energy With Interactions And The Stability Of Dynamical System

In recent years the astronomical observations have shown that our universe is going through a period of accelerating expansion.What causes accelerating expansion of universe has become a hot topic.The theory of dark energy was put forward in order to explain the expand of uni-verse.Several kinds of dark energy models,such as cosmological constant model?Quintessence model?Phantom model?Agegraphic model?Inflessence model and so on have been construct-ed,Which has own advantages and disadvantages.So far the cosmological constant model only agrees well with the observation data.Firstly,we briefly summarize the development history of cosmology in the beginning of this thesis.And then we introduce the basis knowledge of modern cosmology that including standard cosmological model and some problems(such as horizon problem,flatness problem)in it,inflationary cosmology model and the explanation to the problems of standard cosmological model.At the same time,for the sake of explaining the accelerating expansion of universe,other several dark energy models are analyzed in detail.Secondly,in the flat FRW universe,we deeply investigate the generalized ghost dark en-ergy model with different interaction forms.The contents of this thesis include the evolution of cosmological parameters such as the density parameter ?de,parameter of equation of s-tate(EoS)?de and deceleration parameter q of dark energy.The results show that the EoS parameter ?de can cross the phantom divide under the influences of three kinds of differen-t interactions,and the values of the cosmological parameters are in good agreement with the observation data.Furthermore,the evolutional trajectories of the generalized ghost dark energy model in the statefinder parameter r-s?r-q??'de-?de planes are plotted and the discrimina-tion between this scenario and cosmological constant model is illustrated.Finally,we discuss the dynamical properties of the generalized ghost dark energy model?the behavior of the attractor and its stability at the critical point under three different forms of interaction.By calculation,the attractors will be obtained under two kinds of interaction forms,and then we draw the phase diagrams describing the stable points.