12/09/2024 Un autre Big Bang

New Scientist The other big bang 10 nov 2023

Même si aujourd’hui les physiciens ne discutent plus de la pertinence du concept de matière noire, laquelle donnerait une équilibre gravitationnel à un univers constitué d’à peine un quart de matière ordinaire, il reste qu’aucune particule d’une telle matière n’a encore été identifiée.

Certes aujourd’hui un grand nombre de signaux anormaux dans les données provenant des instruments censés observer l’univers jeune commencent à être recueillis.

Bien qu’encore controversés, ils semblent conforter l’existence de WIMPs ou Weakly interacting massive particle. Cependant aucune preuve précise concernant l’existence de telles particules noires n’a encore été obtenue

Selon la physicienne américaine Katherine Freeze, ceci pourrait tenir au fait que nous ne tenions pas compte d’un second Big Bang, qu’elle nomme un Big Bang Noir, qui se serait produit peu de temps après le premier

Référence

Submitted on 7 Jan 2017]

Status of Dark Matter in the Universe

Katherine Freese

Over the past few decades, a consensus picture has emerged in which roughly a quarter of the universe consists of dark matter. I begin with a review of the observational evidence for the existence of dark matter: rotation curves of galaxies, gravitational lensing measurements, hot gas in clusters, galaxy formation, primordial nucleosynthesis and cosmic microwave background observations. Then I discuss a number of anomalous signals in a variety of data sets that may point to discovery, though all of them are controversial. The annual modulation in the DAMA detector and/or the gamma-ray excess seen in the Fermi Gamma Ray Space Telescope from the Galactic Center could be due to WIMPs; a 3.5 keV X-ray line from multiple sources could be due to sterile neutrinos; or the 511 keV line in INTEGRAL data could be due to MeV dark matter. All of these would require further confirmation in other experiments or data sets to be proven correct. In addition, a new line of research on dark stars is presented, which suggests that the first stars to exist in the universe were powered by dark matter heating rather than by fusion: the observational possibility of discovering dark matter in this way is discussed.


Proceedings of 14th Marcel Grossman Meeting, MG14, University of Rome « La Sapienza », Rome, July 2015
Subjects:Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Physics – Phenomenology (hep-ph)
Cite as:arXiv:1701.01840 [astro-ph.CO]
 (or arXiv:1701.01840v1 [astro-ph.CO] for this version)
 https://doi.org/10.48550/arXiv.1701.01840 Focus to learn more
Related DOI:https://doi.org/10.1142/S0218271817300129

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