[Évolution des univers en cosmologie des ensembles causaux]
L'application de l'approche des ensembles causaux au problème de la gravitation quantique est basée sur l'hypothèse que l'espace-temps est fondamentalement discret. Le caractère discret de l'espace-temps ouvre la voie à de nouveaux types de lois dynamiques pour la cosmologie, et les modèles de croissance séquentielle classique (CSG) de Rideout et Sorkin constituent une classe intéressante de lois de ce type. Il a été démontré qu'une renormalisation des paramètres dynamiques du modèle CSG survient à chaque fois que l'univers subit un rebond de Big Crunch–Big Bang. Nous proposons dans cet article un moyen de modéliser la création d'un nouvel univers après la singularité d'un trou noir. Nous montrons que la renormalisation des paramètres dynamiques se produit dans un modèle CSG après un tel événement de création. Nous spéculons sur le fait que cela pourrait réaliser certains aspects de la sélection naturelle cosmologique proposée par Smolin.
The causal set approach to the problem of quantum gravity is based on the hypothesis that spacetime is fundamentally discrete. Spacetime discreteness opens the door to novel types of dynamical law for cosmology and the Classical Sequential Growth (CSG) models of Rideout and Sorkin form an interesting class of such laws. It has been shown that a renormalisation of the dynamical parameters of a CSG model occurs whenever the universe undergoes a Big Crunch–Big Bang bounce. In this paper we propose a way to model the creation of a new universe after the singularity of a black hole. We show that renormalisation of dynamical parameters occurs in a CSG model after such a creation event. We speculate that this could realise aspects of Smolin's Cosmological Natural Selection proposal.
Mot clés : Gravitation quantique, Ensembles causaux, Cosmologie
Fay Dowker 1 ; Stav Zalel 1
@article{CRPHYS_2017__18_3-4_246_0,
author = {Fay Dowker and Stav Zalel},
title = {Evolution of universes in causal set cosmology},
journal = {Comptes Rendus. Physique},
pages = {246--253},
publisher = {Elsevier},
volume = {18},
number = {3-4},
year = {2017},
doi = {10.1016/j.crhy.2017.03.002},
language = {en},
}
Fay Dowker; Stav Zalel. Evolution of universes in causal set cosmology. Comptes Rendus. Physique, Volume 18 (2017) no. 3-4, pp. 246-253. doi : 10.1016/j.crhy.2017.03.002. https://comptes-rendus.academie-sciences.fr/physique/articles/10.1016/j.crhy.2017.03.002/
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