Dark Energy and Non–linear Perturbations
نویسنده
چکیده
One of the most important goals of contemporary cosmology is to unreveal the properties of dark energy. This energy form is thought to be responsible for the observed accelerating expansion of the present day universe. There are several methods used to study the properties of dark energy. The important ones make use of the anisotropies in the Cosmic Microwave Background Radiation (CMB), the evolution of large scale structure formation (LSS) and/or the distances of high redshift supernovae (see e.g. the overview by Peebles and Ratra). In this contribution we address the question whether dark energy can have some impact on the formation of non–linear structures in the universe, such as clusters of galaxies or galaxies itself. In doing so, we assume that dark energy is a scalar field, pervading the universe. It will obviously
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