A Time-dependent Cosmological Constant Phenomenology

Salvatore Capozziello; Ruggiero de Ritis; Alma Angela Marino

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A Time-dependent Cosmological Constant Phenomenology

Salvatore Capozziello·Ruggiero de Ritis·Alma Angela Marino

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Abstract

We construct a cosmological toy model in which a step-function ``cosmological constant'' is taken into consideration beside ordinary matter. We assume that $Λ$ takes two values depending on the epoch, and matter goes from a radiation dominated era to a dust dominated era. The model is exactly solvable and it can be compared with recent observations.

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Salvatore Capozziello, Ruggiero de Ritis, Alma Angela Marino. 1996-05-29. A Time-dependent Cosmological Constant Phenomenology. https://arxiv.org/abs/astro-ph/9605176

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