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arXiv · 2505.13240

Did the Corona Borealis-A2142 supercluster binary-like system originate as a proto-cluster binary embedded in a primordial cloud of galaxies?

Giovanni C. Baiesi Pillastrini
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Abstract

The formation of the giant binary-like system composed by the Corona Borealis and Abell 2142 superclusters is an intriguing conundrum of the formation of large scale structures since, from the observational point of view, it represents a rare peculiarity in the distribution of massive galaxy superclusters. Having a configuration similar to a giant binary system interconnected by a huge filament, it is likely one if not the unique case to date observed in the Local Universe. So a question arise: how and when did it form? Here, the CrB and A2142 system has been hypothesized to be a descendent of a primordial binary system composed of two close galaxy proto-clusters, the CrB and A2142, originated from two independent collapsing process within a dense cloud of galaxies. Then, assuming that at a certain point the decoupling occurred due to the interplay of gravity-antigravity of DE, they began to move away in radial motion from each other following the accelerate expansion of the Universe. In the context of the LCDM model a Newtonian approximation of the two body motion in presence of DE has been applied using current physical parameters of the CrB and A2142 system with the aim to calculate the look-back time at decoupling. Its compatibility with the era of formation of the primordial galaxy proto-clusters has been tested. The event of the binary decoupling happened in a time larger than the age of the Universe! Of course, after such a result the advanced hypothesis on the origins of the CrB-A2142 system can be rejected, but not the test of compatibility since the look-back time at the error lower limit is 12.5 Gys ( z = 4.5) largely consistent with observations.

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Giovanni C. Baiesi Pillastrini. 2025-11-21. Did the Corona Borealis-A2142 supercluster binary-like system originate as a proto-cluster binary embedded in a primordial cloud of galaxies?. https://arxiv.org/abs/2505.13240

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