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We present the Big-Bang Nucleosynthesis (BBN) simulation with a bubble universe scenario around a rotating black hole (BH) in Kerr-AdS$_5$ spacetime to explain recently updated observations of light elements such as the primordial helium…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-17 Akira Dohi , Issei Koga , Kazushige Ueda

We present a new astrophysical site of the big bang nucleosynthesis (BBN) that are very peculiar compared with the standard BBN. Some models of the baryogenesis suggest that very high baryon density regions were formed in the early…

Astrophysics · Physics 2009-11-13 S. Matsuura , S. Fujimoto , S. Nishimura , M. Hashimoto , K. Sato

A review of the latest measurements of the primordial abundances of the light nuclei D, 3He, 4He and 7Li is given. We discuss in particular the primordial abundance Yp of 4He as measured in blue compact dwarf galaxies. We argue that the…

Astrophysics · Physics 2007-05-23 T. X. Thuan , Y. I. Izotov

We reexamine big bang nucleosynthesis with large-scale baryon density inhomogeneities when the length scale of the density fluctuations exceeds the neutron diffusion length ($\sim 10^7-10^8$ cm at BBN), and the amplitude of the fluctuations…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-12 John D. Barrow , Robert J. Scherrer

One of the most compelling pieces of evidence of the Hot Big Bang model is the realisation and confirmation that some nuclides were created shortly after the Big Bang. This process is referred to as Big Bang nucleosynthesis (or, sometimes,…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-11 Ryan Cooke

One of the three testaments in favor of the big bang theory is the prediction of the primordial elemental abundances in the big-bang nucleosynthesis (BBN). The Standard BBN is a parameter-free theory due to the precise knowledge of the…

Nuclear Theory · Physics 2024-05-28 Vinay Singh , Debasis Bhowmick , D. N. Basu

We study big bang nucleosynthesis in the presence of large mass-scale, non-linear entropy fluctuations. Overdense regions, with masses above the local baryon-Jeans mass, are expected to collapse and form condensed objects. Surviving…

Astrophysics · Physics 2009-10-22 K. Jedamzik , G. M. Fuller

The universe would have been completely dark between the epoch of recombination and the development of the first non-linear structure. But at redshifts beyond 5 -- perhaps even beyond 20 -- stars formed within `subgalaxies' and created the…

Astrophysics · Physics 2009-10-31 Martin J. Rees

The abundances of light elements based on the big bang nucleosynthesis model are calculated using the Tsallis non-extensive statistics. The impact of the variation of the non-extensive parameter $q$ from the unity value is compared to…

Nuclear Theory · Physics 2015-06-05 C. A. Bertulani , J. Fuqua , M. S. Hussein

We investigate Big Bang nucleosynthesis (hereafter, BBN) in a cosmic environment characterized by a distribution of small-scale matter/antimatter domains. Production of antimatter domains in a baryo-asymmetric universe is predicted in some…

Astrophysics · Physics 2009-10-30 Jan B. Rehm , Karsten Jedamzik

Physics, as known from our local, around--earth experience, meets some of its applicability limits at the time just preceding the period of primeval nucleosynthesis. Attention is focussed here on the effects of the nucleon size.…

General Relativity and Quantum Cosmology · Physics 2007-05-23 R. Aldrovandi , J. Gariel , G. Marcilhacy

The apparent discrepancy between abundances of light nuclides predicted by the standard Big-Bang and observational data is explained, by assuming the presence of metastable H dibaryons at the nucleosynthesis era. These dibaryons could be…

Astrophysics · Physics 2009-10-31 J. A. de Freitas Pacheco , S. Stoica , F. Thevenin , J. E. Horvath

Stellar nucleosynthesis is an important nuclear physics phenomenon that is responsible for presently observed chemical elements and isotope abundances. It is also one of the corner stone hypotheses that provides basis for our understanding…

Solar and Stellar Astrophysics · Physics 2012-03-09 Boris Pritychenko

We investigate a class of universes in which the weak interaction is not in operation. We consider how astrophysical processes are altered in the absence of weak forces, including Big Bang Nucleosynthesis (BBN), galaxy formation, molecular…

Astrophysics of Galaxies · Physics 2018-03-14 E. Grohs , Alex R. Howe , Fred C. Adams

We discuss the fine-tunings of nuclear reactions in the Big Bang and in stars and draw some conclusions on the emergence of the light elements and the life-relevant elements carbon and oxygen. We also stress how to improve these…

Nuclear Theory · Physics 2025-03-21 Ulf-G. Meißner , Bernard Ch. Metsch , Helen Meyer

A review of Big Bang Nucleosynthesis (BBN) is presented. Observations of deuterium and helium-4 are discussed. Some BBN restrictions on non-standard physics, especially on neutrino properties and time-variation of fundamental constants are…

High Energy Physics - Phenomenology · Physics 2015-06-25 A. D. Dolgov

Primordial nucleosynthesis, or big bang nucleosynthesis (BBN), is one of the three evidences for the big bang model, together with the expansion of the universe and the cosmic microwave background. There is a good global agreement over a…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-20 Alain Coc , Elisabeth Vangioni

We extend the model-independent likelihood analysis of big bang nucleosynthesis (BBN) based on He4 and Li7 to allow for numbers of degrees of freedom which differ from the standard model value characterized by $N_\nu = 3$. We use the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Keith A. Olive , David Thomas

We outline how relic neutrino asymmetries may be generated in the early universe via active-sterile neutrino oscillations. We discuss possible consequences for big bang nucleosynthesis, within the context of a particular 4-neutrino model.

High Energy Physics - Phenomenology · Physics 2008-11-26 Nicole F. Bell

A new evaluation of the constraint on the number of light neutrino species (N_nu) from big bang nucleosynthesis suggests a discrepancy between the predicted light element abundances and those inferred from observations, unless the inferred…

High Energy Physics - Phenomenology · Physics 2009-04-13 N. Hata , R. J. Scherrer , G. Steigman , D. Thomas , T. P. Walker , S. Bludman , P. Langacker
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