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Related papers: From primordial $^4$He abundance to the Higgs fiel…

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We predict the primordial deuterium abundance using a novel, fully data-driven approach, where we use Gaussian process regression to fit experimental nuclear reaction data for $d$,($d$,$n$)$^3$He, $d$,($d$,$p$)$t$, and…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-21 Timothy Launders , Cara Giovanetti , Hongwan Liu

After few minutes the Universe evolved through conditions of temperature and density which permitted the first synthesis of astrophysically interesting abundances of D, 3He, 4He and 7Li. The relic abundances are sensitive probes of the…

Astrophysics · Physics 2007-08-30 Paolo Molaro

We analyze the effect of variation of fundamental couplings and mass scales on primordial nucleosynthesis in a systematic way. The first step establishes the response of primordial element abundances to the variation of a large number of…

Astrophysics · Physics 2008-12-18 Thomas Dent , Steffen Stern , Christof Wetterich

The discordance between `low' and `high' primordial D/H measurements can be considerably reduced if the analysis of the H+D profiles accounts for the correlated velocity field of bulk motion. We have re-estimated the value of D/H at z=3.572…

Astrophysics · Physics 2007-05-23 Sergei A. Levshakov

Big Bang Nucleosynthesis (BBN) relates key cosmological parameters to the primordial abundance of light elements. In this paper, we point out that the recent observations of Cosmic Microwave Background anisotropies by the Planck satellite…

Cosmology and Nongalactic Astrophysics · Physics 2014-08-06 Eleonora Di Valentino , Carlo Gustavino , Julien Lesgourgues , Gianpiero Mangano , Alessandro Melchiorri , Gennaro Miele , Ofelia Pisanti

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 reanalyze the allowed parameters for inhomogeneous big bang nucleosynthesis in light of the WMAP constraints on the baryon-to-photon ratio and a recent measurement which has set the neutron lifetime to be 878.5 +/- 0.7 +/- 0.3 seconds.…

Astrophysics · Physics 2008-11-26 J. F. Lara , T. Kajino , G. J. Mathews

We discuss that it is quite possible to realize the smooth transition of the universe between a matter/radiation dominated deceleration and a dark energy dominated acceleration, even with a variation of proton-to-electron mass ratio. The…

General Relativity and Quantum Cosmology · Physics 2021-07-14 Soumya Chakrabarti

Estimates of the deuterium abundance in quasar absorbers are reviewed, including a brief account of incorrect claims published by the author and a brief review of the problem of hydrogen contamination. It is concluded that the primordial…

Astrophysics · Physics 2007-05-23 Craig J. Hogan

We point out that the recent result of primordial helium-4 ($^4$He) abundance measurement by EMPRESS, which has reported a smaller $^4$He abundance than other measurements, can be well fitted by assuming a time-variation of the fine…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-09 Osamu Seto , Tomo Takahashi , Yo Toda

We reinvestigate the constraints from primordial nucleosynthesis on a possible time-dependent quark mass. The limits on such quark-mass variations are particularly sensitive to the adopted observational abundance constraints. Hence, in the…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-06 Myung-Ki Cheoun , Toshitaka Kajino , Motohiko Kusakabe , Grant J. Mathews

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

In extended quintessence models, a scalar field which couples to the curvature scalar R provides most of the energy density of the universe. We point out that such models can also lead naturally to a decrease in the primordial abundance of…

Astrophysics · Physics 2009-10-31 Xuelei Chen , Robert J. Scherrer , Gary Steigman

The Higgs mass value is derived from a Hamiltonian on the Lie group U(3) where we relate strong and electroweak energy scales. The baryon states of nucleon and delta resonances originate in specific Bloch wave degrees of freedom coupled to…

General Physics · Physics 2015-07-08 Ole L. Trinhammer , Henrik G. Bohr , Mogens Stibius Jensen

Primordial abundances of light elements are sensitive to the physics of the early Universe and can directly constrain cosmological quantities, such as the baryon-to-photon ratio $\eta_{10}$, the baryon density and the number of neutrino…

We show that the predicted primordial helium production is significantly reduced when new measurements of the neutron lifetime and the implied enhancement in the weak reaction rates are included in big-bang nucleosynthesis. Therefore, even…

Astrophysics · Physics 2009-11-10 G. J. Mathews , T. Kajino , T. Shima

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 have modified the standard code for primordial nucleosynthesis to include the effect of finite nucleon mass on the weak-interaction rates as calculated by Seckel \cite{seckel}. We find a small, systematic increase in the $^4$He yield,…

Astrophysics · Physics 2007-05-23 Geza Gyuk , Michael S. Turner

We study the dependence of primordial nuclear abundances on fundamental nuclear observables such as binding energies, scattering lengths, neutron lifetime, \textit{etc.} by varying these quantities. The numerical computations were performed…

Nuclear Theory · Physics 2022-11-23 Ulf-G. Meißner , Bernard Ch. Metsch

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