The black matter is a very important concept in modern cosmology and astrophysics. This file will present all the problems that are grouped under the name of dark matter.
First, in a number of astrophysical objects, the movements observed are different from those expected in theory, when one tries to deduce them from the gravitational action of the observed masses, everything happens as if an invisible mass density were present.
Then, the standard model of formation of large structures in theUniversewhich explains on the one hand how the galaxies and the clusters of galaxies are formed, and on the other hand the properties of the cosmic background radiation, only makes it possible to account for the observations on condition that theuniverse contains a large amount of mass in a form different from ordinary matter.
Finally, the cosmology in general delivers crucial information on the content of the universe, whether through the study of its geometry or that of its history. The results clearly indicate that the universe contains more matter than is seen.
Matter: an enigma in astrophysics and cosmology
Several questions then arise: does dark matter really exist? If so what is it? If not, where do the problems we have just mentioned come from? »
It would be satisfying to solve these three problems at the same time, and the use of a common term dark matter has at least the psychological merit of maintaining this hope, but it must be admitted that this goal has not yet been achieved. This is not a pure acknowledgment of failure, because the existence of these dark matter problems has motivated a large number of researches which have led to discoveries important in astrophysics and cosmology.
In this dossier, we will begin by presenting the various clues that lead to the dark matter hypothesis. Then, we will present several proposals that have been made to try to answer the question ” what is this dark matter made of? “. Finally, we will discuss some of the many experiments that could provide some answers to this question.