The standard cosmological model boasts many successes. It is based on the existence ofof of a constant called lambda (Λ) in ancient Greek and which is nothing but Einstein’s famous cosmological constant. Λ behaves as a density of and that is why we are talking about the existence of in . It is further hypothesized that this energy, which behaves as one repulsive acceleration of the expansion of the observable cosmos for a few billion years, does not vary in space and time, although it becomes more and more dominant in terms of matter because it does not dilute as it would expanding particles.
Let us now talk about the material content ofaccurately observable. Within the framework of the standard cosmological model, it is dominated by which are believed to consist of particles never before seen on Earth in accelerators or detectors, and which can not interact with standard baryonic matter and with themselves solely by gravity. This material is also almost essential for explaining the properties of fossil radiation and simply the existence of .
For 13.7 billion years, the universe has continued to evolve. Contrary to what our eyes tell us when we look at the sky, what is made up of is far from static. Physicists have observations at different ages of the universe and perform simulations in which they reflect its formation and its evolution. It seems that dark matter has played a major role from the beginning of the universe until the formation of the large structures observed today. © ECA
The standard cosmological model (called ΛCDM with CDM for cold dark fabric, that is, “cold dark matter”) is not perfect, and it also leads to paradoxes and apparent contradictions with the experiment, which leaves the suspicion that it would no doubt be necessary to change it a little. The disagreement between the two assessments of the famous constant in the Hubble-Lemaître law regarding the expansion of space has thus provided food for thought for those who believe thatis perhaps not so constant.
Similar problems with characteristics ofsatellites from large galaxies suggest that there are poorly understood interactions between dark matter and ordinary matter, perhaps even between dark matter particles themselves.
A dark fabric halo in development
But quite recently, a team – mostly made up of researchers from Scuola Internazionale Superiore di Studi Avanzati (Sissa) in Italy, Gauri Sharma, Paolo Salucci and Glenn van de Ven – published the results of their work with an article in the prestigious journal.
Thatlooked more closely at the content of dark matter of about 300 large like the Milky Way and Andromeda, perform a kind time in our past, almost 7 billion years back.
Like their predecessors, like thatthey measured from from and of atomic to be able to extend beyond the visible edges of these spiral galaxies using especially . These movements are indicative of the presence and distribution of hidden, precisely dark matter, unless the laws of celestial mechanics are modified within the framework of as some researchers have suggested doing.
It then appears that in the heart of the halos of dark matter enclosing the spiral galaxies is a zone of homogeneous overdensity, the size of which increases over time until it flows over the spiral galaxies.
Everything happens therefore, according to the researchers, as if dark matter had a mysterious further interaction with normal matter, an interaction that forces the dark matter of the halo to concentrate in such a way that it increases the size of this central core of homogeneous but decreasing density over time.
At present, this does not fit at all with the basic assumptions of the basic cosmological model, and it therefore provides new limitations and information about the nature of dark matter, the exact meaning of which needs to be explored.