When an alignment of supermassive black holes occurs
The prediction of structures in our cosmological modelIn theory, numerical models predict the existence of cosmic webs, structures existing between different objects of the cosmos. These structures result from the fact that the Universe, on a smaller scale, is not homogenous. Objects are not uniformly distributed throughout space. Over the course of billions of years, they groupe and create denser volumes in the distribution of matter in the Universe. On a very large scale, the structure of the Universe appears like a web composed of interconnected filaments. These filaments mark the boundaries of “voids”, where the density of galaxies or clusters of galaxies is smaller than in the filaments. Up to a certain scale, observations confirm and support this theory. “This is the limit of our models”, explains Vincent Pelgrims, a doctoral student at AGO and coauthor of the publication. “They predict that galaxies can organize themselves into filaments that look like neuronal connections but are much bigger of course. “These cosmic webs depend on gravitational force”, continues Dominique Sluse, a researcher at the Argelander Institute of Astronomy in Bonn and the University of Liege. “The models show that, under the influence of gravity, the angular momentum, therefore the rotational axes of galaxies, are linked to the orientation of the structure to which they belong”. The suspected existence of a quasar structureIn this context, the observation of these 93 quasars has become interesting. Such a high density of these objects in the same region of the sky raised suspicions. “The recent discovery of this group was already surprising”, explains Dominique Sluse. “Observing this overdensity of quasars was a first step which allowed astronomers to speculate that it was probably a structure that was bigger than one gigaparsec, that is to say, more than 3.26 billion light years, at a time when the Universe was only 5 billion years old. This is ten times bigger than the structures that are usually observed and three times bigger than the predicted limit of the standard model. But was this the result of chance or not? Was this really a single individual structure or were we missing something? It was difficult to say”. |
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