Abstract:
The maximum allowable size of a spherical cosmic structure as a function of its mass is determined by the
maximum turn around radius RTA,max, the distance from its
center where the attraction on a radial test particle due to the
spherical mass is balanced with the repulsion due to the ambient dark energy. In this work, we extend the existing results
in several directions. (a) We first show that, for w = −1, the
expression for RTA,max found earlier, using the cosmological
perturbation theory, can be derived using a static geometry
as well. (b) In the generic dark energy model with arbitrary
time dependent state parameter w(t), taking into account the
effect of inhomogeneities upon the dark energy as well, it is
shown that the data constrain w(t = today) > −2.3. (c) We
address the quintessence and the generalized Chaplygin gas
models, both of which are shown to predict structure sizes
consistent with observations.
