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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…

天体物理学 · 物理学 2008-11-26 Christian M. Mueller , Gregor Schaefer , Christof Wetterich

In this study we present a comprehensive sensitivity atlas for Big Bang Nucleosynthesis (BBN) in which we quantify the dependence of the primordial abundances of helium-4, deuterium, and lithium-7 as well as $N_{\rm{eff}}$ on variations in…

高能物理 - 唯象学 · 物理学 2026-03-25 Anne-Katherine Burns

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…

Primordial or big bang nucleosynthesis (BBN) is one of the three historical strong evidences for the big bang model. The recent results by the Planck satellite mission have slightly changed the estimate of the baryonic density compared to…

宇宙学与河外天体物理 · 物理学 2015-06-19 Alain Coc , Jean-Philippe Uzan , Elisabeth Vangioni

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…

宇宙学与河外天体物理 · 物理学 2013-06-25 Mahnaz Q. Haseeb , Obaidullah Jan , Omair Sarfaraz

We put bounds on the variation of the value of the fine structure constant $\alpha$, at the time of Big Bang nucleosynthesis. We study carefully all light elements up to $^7$Li. We correct a previous upper limit on $|\Delta \alpha /…

天体物理学 · 物理学 2009-10-31 L. Bergstrom , S. Iguri , H. Rubinstein

The light element lithium is formed by nucleosynthesis during the Big Bang. Its abundance can help to define the parameters of the early universe. To find this primordial value, it is necessary to determine Li abundances in the oldest stars…

太阳与恒星天体物理 · 物理学 2023-07-28 Ann Merchant Boesgaard , Constantine P. Deliyannis

Big Bang Nucleosynthesis provides us with an observational insight into the very early Universe. Since this mechanism of light element synthesis comes out of the standard model of particle cosmology which follows directly from General…

宇宙学与河外天体物理 · 物理学 2023-12-14 Sai Swagat Mishra , Ameya Kolhatkar , P. K. Sahoo

Recent cosmological observations, such as the measurement of the primordial 4He abundance, CMB, and large scale structure, give preference to the existence of extra radiation component, Delta N_nu > 0. The extra radiation may be accounted…

高能物理 - 唯象学 · 物理学 2011-06-27 Kazunori Nakayama , Fuminobu Takahashi , Tsutomu T. Yanagida

We present a model for big bang nucleosynthesis which combines baryon inhomogeneities with the effects of the decays of massive particles (masses higher than a few GeV). Those particles, with half-lives longer than the standard…

天体物理学 · 物理学 2007-05-23 J. Lopez-Suarez , R. Canal

The primordial abundances of deuterium, helium-3, helium-4, and lithium-7 probe the baryon density of the Universe only a few minutes after the Big Bang. Of these relics from the early Universe, deuterium is the baryometer of choice. After…

天体物理学 · 物理学 2007-05-23 Gary Steigman

Standard Big Bang Nucleosynthesis (BBN) predicts the abundances of the light elements in the early universe. Even if the overall agreement with the experimental data is good, still some discrepancies exist on the relic abundances of…

核理论 · 物理学 2020-12-16 Alex Gnech

Residual late-time dark matter particle annihilations during and after Big Bang Nucleosynthesis (BBN) may alter the predicted cosmological abundances of the light elements. Within the constrained minimal supersymmetric extension of the…

宇宙学与河外天体物理 · 物理学 2013-05-29 John Ellis , Brian D. Fields , Feng Luo , Keith A. Olive , Vassilis C. Spanos

The early universe provides a unique laboratory for probing the frontiers of particle physics in general and neutrino physics in particular. The primordial abundances of the relic nuclei produced during the first few minutes of the…

高能物理 - 唯象学 · 物理学 2009-11-11 Gary Steigman

We compute the big bang nucleosynthesis limit on the number of light neutrino degrees of freedom in a model-independent likelihood analysis based on the abundances of He4 and Li7. We use the two-dimensional likelihood functions to…

高能物理 - 唯象学 · 物理学 2008-11-26 Keith A. Olive , David Thomas

Big bang nucleosynthesis in a modified gravity model of $f(R)\propto R^n$ is investigated. The only free parameter of the model is a power-law index $n$. We find cosmological solutions in a parameter region of $1< n \leq (4+\sqrt{6})/5$. We…

宇宙学与河外天体物理 · 物理学 2015-07-21 Motohiko Kusakabe , Seoktae Koh , K. S. Kim , Myung-Ki Cheoun

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…

天体物理学 · 物理学 2009-10-30 Jan B. Rehm , Karsten Jedamzik

Recently, the first lithium detection outside of the Milky Way was made in low-metallicity gas of the Small Magellanic Cloud, which was at the level of the expected primordial value. Part of the observed lithium in any environment has…

高能天体物理现象 · 物理学 2016-10-12 A. Ćiprijanović

The light relic density affects the thermal and expansion history of the early Universe leaving a number of observable imprints. We focus on the primordial abundances of light elements produced during the process of Big Bang nucleosynthesis…

宇宙学与河外天体物理 · 物理学 2020-02-19 Alex Laguë , Joel Meyers

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…

核理论 · 物理学 2007-05-23 Daksh Lohiya , Annu Batra , Shobhit Mahajan , Amitabha Mukherjee