We investigate a coupled quintessence scenario, which can provide a natural solution to the cosmic coincidence problem. We assume that the mass of dark matter particles depends on a power law function of the scalar fi...We investigate a coupled quintessence scenario, which can provide a natural solution to the cosmic coincidence problem. We assume that the mass of dark matter particles depends on a power law function of the scalar field associated to dark energy and meanwhile the scalar field evolves in a power law potential. Since the dynamics of this system is dominated by an attractor solution, the mass of dark matter particles is forced to change with time as to ensure that the ratio between the energy densities of dark matter and dark energy becomes a constant at late times,and one thus solves the cosmic coincidence problem naturally. We then apply a statefinder diagnostic to this coupled quintessence scenario. It is shown that the evolving trajectory of this scenario in the s-r diagram is quite different from those of other dark energy models.展开更多
Exchange and cooperation in the field of human rights education, between higher education and research institutions in the Chinese mainland and foreign human rights institutions and relevant international organization...Exchange and cooperation in the field of human rights education, between higher education and research institutions in the Chinese mainland and foreign human rights institutions and relevant international organizations, are an important aspect of human rights exchange and cooperation between the Chinese mainland and foreign countries. The China University of Political Science and Law is the first university in the mainland to establish the human rights law discipline and one of the first national human rights education and training bases, playing an exemplary and leading role in the field of human rights education and foreign exchange and cooperation. Summaries and analyses of the background, objectives,展开更多
文摘We investigate a coupled quintessence scenario, which can provide a natural solution to the cosmic coincidence problem. We assume that the mass of dark matter particles depends on a power law function of the scalar field associated to dark energy and meanwhile the scalar field evolves in a power law potential. Since the dynamics of this system is dominated by an attractor solution, the mass of dark matter particles is forced to change with time as to ensure that the ratio between the energy densities of dark matter and dark energy becomes a constant at late times,and one thus solves the cosmic coincidence problem naturally. We then apply a statefinder diagnostic to this coupled quintessence scenario. It is shown that the evolving trajectory of this scenario in the s-r diagram is quite different from those of other dark energy models.
文摘Exchange and cooperation in the field of human rights education, between higher education and research institutions in the Chinese mainland and foreign human rights institutions and relevant international organizations, are an important aspect of human rights exchange and cooperation between the Chinese mainland and foreign countries. The China University of Political Science and Law is the first university in the mainland to establish the human rights law discipline and one of the first national human rights education and training bases, playing an exemplary and leading role in the field of human rights education and foreign exchange and cooperation. Summaries and analyses of the background, objectives,