The Spherical Collapse Model in a Universe with Cosmological Constant
نویسنده
چکیده
The spherical collapse model was first developed by Gunn & Gott 1 for a flat universe with no cosmological constant. It assumes that the process of formation of bound objects in the universe can be at first approximation described by evolution of an uniformly overdense spherical region in otherwise smooth background. Despite its simplicity, the model has been widely used to explain properties of a single bound object via extensions such as the spherical infall model as well as statistical properties of different classes of objects via Press-Schechter-like formalisms. Given the presently mounting evidence for cosmological constant we generalize the model here to include its effect.
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