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Electron mass is known to modify at finite temperatures and densities. Weak nuclear processes have a great impact on electron mass which modifies in a statistical background. We demonstrate how the temperature change in electron mass is…

High Energy Astrophysical Phenomena · Physics 2024-12-31 Samina Masood , Jaskeerat Singh

The success of primordial nucleosynthesis has been limited by the long-standing Lithium problem. We use a self-consistent perturbative analysis of the effects of relevant theoretical parameters on primordial nucleosynthesis, including…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-08 M. Deal , C. J. A. P. Martins

We calculate bounds on the variation of the fine structure constant at the time of primordial nucleosynthesis and at the time of neutral hydrogen formation. We use these bounds and other bounds from the late universe to test Bekenstein…

Primordial nucleosynthesis is inevitable during the early evolution of an expanding universe filled with radiation and matter (baryons). However, the precise abundance yields depend sensitively on the baryon density, the radiation content…

Astrophysics · Physics 2007-05-23 Gary Steigman

The theoretical predictions of the primordial abundances of elements in the big-bang nucleosynthesis (BBN) are dominated by uncertainties in the input nuclear reaction rates. We investigate the effect of modifying these reaction rates on…

Nuclear Theory · Physics 2014-06-03 Abhishek Mishra , D. N. Basu

Big Bang nucleosynthesis (BBN) is the earliest sensitive probe of the values of many fundamental particle physics parameters. We have found the leading linear dependences of primordial abundances on all relevant parameters of the standard…

Astrophysics · Physics 2008-11-26 Thomas Dent , Steffen Stern

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

Primordial or big bang nucleosynthesis (BBN) is one of the three historical strong evidences for the big bang model. Standard BBN is now a parameter free theory, since the baryonic density of the Universe has been deduced with an…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-30 Alain Coc , Patrick Petitjean , Jean-Philippe Uzan , Elisabeth Vangioni , Pierre Descouvemont , Christian Illiadis , Richard Longland

We discuss the effects of a possible time variation of the Newton constant $G_{\rm N}$ on light elements production in Big Bang Nucleosyntesis (BBN). We provide analytical estimates for the dependence of primordial abundances on the value…

Astrophysics · Physics 2008-11-26 C. Bambi , M. Giannotti , F. L. Villante

We report the results of a new accurate evaluation of light nuclei yields in primordial nucleosynthesis. All radiative effects, finite nucleon mass, thermal and plasma corrections are included in the proton to neutron conversion rates. The…

Astrophysics · Physics 2008-11-26 S. Esposito , G. Mangano , G. Miele , O. Pisanti

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

A critical review is given of the current status of cosmological nucleosynthesis. In the framework of the Standard Model with 3 types of relativistic neutrinos, the baryon-to-photon ratio, $\eta$, corresponding to the inferred primordial…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Brian D. Fields , Paolo Molaro , Subir Sarkar

We determine the influence of a variation of the fundamental ``constants'' on the predicted helium abundance in Big Bang Nucleosynthesis. The analytic estimate is performed in two parts: the first step determines the dependence of the…

Astrophysics · Physics 2008-11-26 Christian M. Mueller , Gregor Schaefer , Christof Wetterich

A variation of the fundamental constants is expected to affect the thermonuclear rates important for stellar nucleosynthesis. In particular, because of the very small resonant energies of Be8 and C12, the triple $\alpha$ process is…

Solar and Stellar Astrophysics · Physics 2014-11-20 Sylvia Ekstrom , Alain Coc , Pierre Descouvemont , Georges Meynet , Keith A. Olive , Jean-Philippe Uzan , Elisabeth Vangioni

We study the fine-structure constant dependence of the rates of some selected radiative capture reactions within the framework of so-called Halo Effective Field Theory in order to assess the adequacy of some assumptions made on the Coulomb…

Nuclear Theory · Physics 2024-10-17 Ulf-G. Meißner , Bernard Ch. Metsch , Helen Meyer

In the standard hot big bang nucleosynthesis (BBN) model the primordial abundances of H, H2, He3, He4, and Li7, fix the baryon density of the universe, $\Omega_b$, via the baryon-to-photon ratio, $\eta$, for a given Hubble parameter. Recent…

Astrophysics · Physics 2009-10-31 S. G. Ryan , T. C. Beers , K. A. Olive , B. D. Fields , J. E. Norris

We extend a recently developed Big Bang Nucleosynthesis (BBN) code, {\tt PRyMordial}, to constrain a broad class of Grand Unified Theories to which BBN is sensitive, since these lead to varying fundamental couplings. A previously developed…

High Energy Physics - Phenomenology · Physics 2026-04-07 I. M. Dreyer , C. J. A. P. Martins

Abundances of light nuclei formed during primordial nucleosynthesis are predicted by Standard Big Bang Model. The latest data from WMAP, with precision's higher than ever before, provides a motivation to determine theoretical higher order…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-25 Mahnaz Q. Haseeb , Obaidullah Jan , Omair Sarfaraz

Big Bang Nucleosynthesis (BBN) explores the first few minutes of nuclei formation after the Big Bang. We present updates that result in new constraints at the 2{\sigma} level for the abundances of the four primary light nuclides -…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-20 Michael Foley , Nishanth Sasankan , Motohiko Kusakabe , Grant. J. Mathews

In this work we show that the cosmological lithium problem and the $H_0$ tension could be eased at the same time by allowing variations in the fundamental constants. We compute the primordial abundances of light elements resulting from Big…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-07 S. A. Franchino-Viñas , M. E. Mosquera