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We use Big Bang Nucleosynthesis calculations and light element abundance data to constrain the relative variation of the deuteron binding energy since the universe was a few minutes old, $\delta Q = Q(BBN)-Q(present)$. Two approaches are…

Astrophysics · Physics 2009-08-18 V. F. Dmitriev , V. V. Flambaum , J. K. Webb

The conventional approach to search for departures from the standard model of physics during Big Bang Nucleosynthesis involves a careful, and subtle measurement of the mass fraction of baryons consisting of helium. Recent measurements of…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-13 Ryan Cooke

Big-bang nucleosynthesis is one of the cornerstones of the standard cosmology. For almost thirty years its predictions have been used to test the big-bang model to within a fraction of a second of the bang. The concordance that exists…

Astrophysics · Physics 2009-10-22 Craig J Copi , David N. Schramm , Michael S. Turner

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

For a brief time in its early evolution the Universe was a cosmic nuclear reactor. The expansion and cooling of the Universe limited this epoch to the first few minutes, allowing time for the synthesis in astrophysically interesting…

Cosmology and Nongalactic Astrophysics · Physics 2010-09-27 Gary Steigman

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

Primordial nucleosynthesis calculations are shown to be able to provide constraints on electroweak baryogenesis which produce a highly inhomogeneous distribution of the baryon-to-photon ratio. Such baryogenesis scenarios overproduce 4He…

Astrophysics · Physics 2009-10-22 G. M. Fuller , K. Jedamzik , G. J. Mathews , A. Olinto

Big Bang Nucleosynthesis (BBN) is studied within the framework of a two-parameter family of tensor-scalar theories of gravitation, with nonlinear scalar-matter coupling function a(phi). We run a BBN code modified by tensor-scalar gravity,…

Astrophysics · Physics 2009-10-30 Thibault Damour , Bernard Pichon

Limits can be placed on nonstandard neutrino physics when big bang nucleosynthesis (BBN) calculations employing standard neutrino physics agree with the observationally inferred primordial abundances of deuterium (D), $^3$He, $^4$He, and…

Astrophysics · Physics 2007-05-23 Christian Y. Cardall , George M. Fuller

Recently, the EMPRESS collaboration has included new data in the extraction of the primordial $^4$He abundance from Big Bang Nucleosynthesis (BBN), resulting in a determination that differs from the previous value and from theoretical…

High Energy Physics - Phenomenology · Physics 2024-05-09 Anne-Katherine Burns , Venus Keus , Marc Sher , Tim M. P. Tait

Two dimensional concordance plots involving the baryon-to-photon ratio, $\eta$, and an effective number of light neutrinos, $N_{\nu}$, are used to discuss the overall consistency of standard big-bang nucleosynthesis in light of recent…

Astrophysics · Physics 2008-11-26 Christian Y. Cardall , George M. Fuller

Using the semi-analytic method proposed by \citet{Esma91} we calculate the abundances of the light elements produced during primordial nucleosynthesis assuming that the gauge coupling constants of the fundamental interactions may vary. We…

Astrophysics · Physics 2008-11-26 Susana J. Landau , Mercedes E. Mosquera , Hector Vucetich

In the standard picture of big-bang nucleosynthesis the yields of D, $^3$He, $^4$He, and $^7$Li only agree with their inferred primordial abundances if the fraction of critical density contributed by baryons is between $0.01h^{-2}$ and…

Astrophysics · Physics 2009-10-22 G. Gyuk , M. S. Turner

We constrain the possible time variation of the Higgs vacuum expectation value ($v$) by recent results on the primordial $^4$He abundance ($Y_P$). For that, we improve the analytic models of the key-processes in our previous analytic…

Astrophysics · Physics 2009-11-13 Josef M. Gaßner , Harald Lesch , Hartmuth Arenhövel

Prediction of the primordial abundances of elements in the big-bang nucleosynthesis (BBN) is one of the three strong evidences for the big bang model. Precise knowledge of the baryon-to-photon ratio of the Universe from observations of the…

Nuclear Theory · Physics 2019-06-24 Vinay Singh , Joydev Lahiri , Debasis Bhowmick , D. N. Basu

The success of primordial nucleosynthesis as a cornerstone of the hot Big Bang model has been limited by the long-standing lithium problem. Recent work presented a self-consistent perturbative analysis of the effects of variations in…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-10 C. J. A. P. Martins

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

The physics of the standard hot big bang cosmology ensures that the early Universe was a primordial nuclear reactor, synthesizing the light nuclides (D, 3He, 4He, and 7Li) in the first 20 minutes of its evolution. After an overview of…

Astrophysics · Physics 2007-05-23 G. Steigman

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

Gravity is attributed to the spacetime curvature in classical General Relativity (GR). But, other equivalent formulation or representations of GR, such as torsion or non-metricity have altered the perception. We consider the Weyl-type $f(Q,…

General Relativity and Quantum Cosmology · Physics 2021-10-20 Gaurav Gadbail , Simran Arora , P. K. Sahoo