[Comprenons-nous vraiment le cosmos ?]
Notre connaissance de l'univers s'est drastiquement accrue au cours de ces trois dernières décennies – grâce au progrès accomplis en matière d'observation – mais notre compréhension de celui-ci ne s'est que très peu améliorée. Il est plusieurs questions fondamentales touchant notre univers pour lesquelles nous n'avons pas de réponses avec l'approche actuelle de la cosmologie, au demeurant couronnée d'un grand succès d'un point de vue opérationnel. Pire encore, nous ne savons même pas comment appréhender certains problèmes dans le cadre de l'approche conventionnelle de la cosmologie. Ceci suggère que des ingrédients théoriques importants d'une description complète du cosmos nous font encore défaut. J'affirmerai ici que ces questions – dont la littérature n'a pas encore pleinement pris la mesure ou suffisamment insisté dessus – exigent un changement de paradigme : nous ne devrions pas penser à l'univers comme étant décrit par une solution spécifique aux équations du champ gravitationnel, mais plutôt comme devant être considéré comme un système physique spécifique gouverné par une description mathématique différente, prenant ses racines dans une description quantique de l'espace-temps. Je soulignerai comment ceci peut être fait.
Our knowledge about the universe has increased tremendously in the last three decades or so — thanks to the progress in observations — but our understanding has improved very little. There are several fundamental questions about our universe for which we have no answers within the current, operationally very successful, approach to cosmology. Worse still, we do not even know how to address some of these issues within the conventional approach to cosmology. This fact suggests that we are missing some important theoretical ingredients in the overall description of the cosmos. I will argue that these issues — some of which are not fully appreciated or emphasized in the literature — demand a paradigm shift: We should not think of the universe as described by a specific solution to the gravitational field equations; instead, it should be treated as a special physical system governed by a different mathematical description, rooted in the quantum description of spacetime. I will outline how this can possibly be done.
@article{CRPHYS_2017__18_3-4_275_0,
author = {Thanu Padmanabhan},
title = {Do we \protect\emph{really} understand the cosmos?},
journal = {Comptes Rendus. Physique},
pages = {275--291},
publisher = {Elsevier},
volume = {18},
number = {3-4},
year = {2017},
doi = {10.1016/j.crhy.2017.02.001},
language = {en},
}
Thanu Padmanabhan. Do we really understand the cosmos?. Comptes Rendus. Physique, Volume 18 (2017) no. 3-4, pp. 275-291. doi : 10.1016/j.crhy.2017.02.001. https://comptes-rendus.academie-sciences.fr/physique/articles/10.1016/j.crhy.2017.02.001/
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