| Popis: |
We present the main results of a model, namely the event‐horizon model, based on a thermodynamical approach for the law of Λ(t).We consider a phenomenological model where we give to the effective cosmological ‘constant’ Λ the physical meaning of a ‘vacuum’ energy density, as usually admitted. In the same vein as the generalization of the black holes [1][2] and of the de Sitter event‐horizon thermodynamics [3][4] to the FLRW space‐time, we associated to this ‘0vacuum’ energy density a full thermodynamics for cosmological event horizons without further microscopic precision about the fields describing the vacuum.Without any ansatz and using thermodynamics arguments, we then deduce the law Λ∝r−2 where r is the proper radius of the event horizon in quasi‐de Sitter FLRW spatially flat spacetime.With this relation, the coincidence problem is solved by the decay of Λ(t) due to the expansion of the universe. We apply this model to the study of the recent accelerated expansion phase and to the coincidence problem.... |
