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Related papers: Big bang nucleosynthesis with rapidly varying G

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Big-bang nucleosynthesis (BBN) probes the cosmic mass-energy density at temperatures $\sim 10$ MeV to $\sim 100$ keV. Here, we consider the effect of a cosmic matter-like species that is non-relativistic and pressureless during BBN. Such a…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-18 Tsung-Han Yeh , Keith A. Olive , Brian D. Fields

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

Oscillations between ordinary and sterile neutrinos can generate large neutrino asymmetries in the early universe. These asymmetries can significantly affect big bang nucleosynthesis (BBN) through modification of nuclear reaction rates. We…

High Energy Physics - Phenomenology · Physics 2011-07-19 N. F. Bell , R. Foot , R. R. Volkas

Primordial nucleosynthesis is considered a success story of the standard big bang (SBB) cosmology. The cosmological and elementary particle physics parameters are believed to be severely constrained by the requirement of correct abundances…

Astrophysics · Physics 2007-05-23 Daksh Lohiya , Shobhit Mahajan , A. Mukherjee , Annu Batra

Primordial nucleosynthesis is an observational cornerstone of the Hot Big Bang model and a sensitive probe of physics beyond the standard model. Its success has been limited by the so-called Lithium problem, for which many solutions have…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-22 M. T. Clara , C. J. A. P. Martins

We consider Big Bang Nucleosynthesis(BBN) with long lived charged massive particles. Before decaying, the long lived massive particles recombines with a light element to form a bound state like a hydrogen atom. We discuss the possible…

High Energy Physics - Phenomenology · Physics 2008-11-26 Kazunori Kohri , Fumihiro Takayama

Primordial nucleosynthesis is considered a success story of the standard big bang (SBB) cosmology. The cosmological and elementary particle physics parameters are believed to be severely constrained by the requirement of correct abundances…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Daksh Lohiya , Annu Batra , Shobhit Mahajan , Amitabha Mukherjee

We present a review of cosmological nucleosynthesis (CN) with neutrino oscillations, discussing the different effects of oscillations on CN, namely: increase of the effective degrees of freedom during CN, spectrum distortion of the…

Astrophysics · Physics 2007-05-23 Daniela Kirilova , Mihail Chizhov

The concordance of standard big bang nucleosynthesis theory and the related observations of the light element isotopes (including some new higher \he4 abundances) will be reviewed. Implications of BBN on chemical evolution, dark matter and…

Astrophysics · Physics 2009-09-15 Keith A. Olive

Standard Big Bang Nucleosynthesis at the baryon density determined by the microwave anisotropy spectrum predicts an excess of \li7 compared to observations by a factor of 4-5. In contrast, BBN predictions for D/H are somewhat below (but…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Keith A. Olive , Patrick Petitjean , Elisabeth Vangioni , Joseph Silk

We consider the effect of inhomogeneous neutrino degeneracy on Big Bang nucleosynthesis for the case where the distribution of neutrino chemical potentials is given by a Gaussian. The chemical potential fluctuations are taken to be…

Astrophysics · Physics 2009-11-07 Spencer D. Stirling , Robert J. Scherrer

Scalar dark matter can interact with Standard Model (SM) particles, altering the fundamental constants of Nature in the process. Changes in the fundamental constants during and prior to Big Bang nucleosynthesis (BBN) produce changes in the…

Cosmology and Nongalactic Astrophysics · Physics 2015-04-14 Y. V. Stadnik , V. V. Flambaum

We study the effect from a general ultralocal supermetric on primordial nucleosynthesis for Friedmann-Robertson-Walker Cosmology. The parameter $\lambda$ of the supermetric changes the effective number of degrees of freedom, $g_*$, which…

Astrophysics · Physics 2010-11-01 A. Llorente , J. Perez-Mercader

Primordial nucleosynthesis is a success story of the standard big bang (SBB) cosmology. We explore nucleosynthesis in possible models very different from SBB in which the cosmological scale factor increases linearly with time right through…

Nuclear Theory · Physics 2007-05-23 Daksh Lohiya , Annu Batra , Shobhit Mahajan , Amitabha Mukherjee

The Hubble expansion of galaxies, the $2.73\dK$ blackbody radiation background and the cosmic abundances of the light elements argue for a hot, dense origin of the universe --- the standard Big Bang cosmology --- and enable its evolution to…

High Energy Physics - Phenomenology · Physics 2011-02-16 Subir Sarkar

A brief review of standard big bang nucleosynthesis theory and the related observations of the light element isotopes is presented. Implications of BBN on chemical evolution and constraints on particle properties will also be discussed.

Astrophysics · Physics 2009-09-15 Keith A. Olive

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 here the effect of a varying G on the evolution of the early Universe and, in particular, on primordial nucleosynthesis. This variation of G is modelled using the Brans-Dicke theory as well as a more general class of scalar-tensor…

Astrophysics · Physics 2009-11-11 T. Clifton , J. D. Barrow , R. J. Scherrer

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 last parameter of big-bang nucleosynthesis, the baryon density, is being pinned down by measurements of the deuterium abundance in high-redshift hydrogen clouds. When it is determined, it will fix the primeval light-element abundances.…

Astrophysics · Physics 2008-11-26 David N. Schramm , Michael S. Turner
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