Perturbations in the relaxation mechanism for a large cosmological constant
نویسنده
چکیده
Recently, a mechanism for relaxing a large cosmological constant (CC) has been proposed [1], which transforms any initial vacuum energy density of arbitrary sign and magnitude into a harmless quantity without fine-tuning. The setup is implemented in the ΛXCDM framework, and it yields a reasonable cosmological background evolution similar to the ΛCDM model with a fine-tuned CC. In this work we analyse analytically the perturbations in this relaxation model, and we show that their evolution is also similar to the ΛCDM model, especially in the matter era. Some tracking properties of the vacuum energy are discussed, too.
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