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相关论文: Constraints on R\'{e}nyi Entropy through Primordia…

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We investigate the concept of Kaniadakis entropy and its dual formulation, examining their implications for gravitational dynamics within the framework where gravity emerges as an entropic force resulting from changes in the informational…

广义相对论与量子宇宙学 · 物理学 2025-12-03 Ahmad Sheykhi , Ava Shahbazi Sooraki , Leila Liravi

Big-bang nucleosynthesis (BBN) theory, together with the precise WMAP cosmic baryon density, makes tight predictions for the abundances of the lightest elements. Deuterium and 4He measurements agree well with expectations, but 7Li…

宇宙学与河外天体物理 · 物理学 2012-03-19 Brian D. Fields

The present article is devoted to constrain the model parameter $\chi$ for the $f(R,T)= R + \chi T$ gravity model by employing the constraints coming from big bang nucleosynthesis. We solve the field equations and constrain $\chi$ in the…

综合物理 · 物理学 2020-04-10 Snehasish Bhattacharjee , P. K. Sahoo

We explore a cosmological model based on R\'enyi entropic corrections to the Friedmann equations and constrain it using DESI, P-BAO, CC, and gravitational-wave observations. Unlike earlier works, we obtain a direct and stringent constraint…

广义相对论与量子宇宙学 · 物理学 2026-04-27 Rajdeep Mazumdar , Kalyan Malakar , Kalyan Bhuyan

To elucidate the significance of the effect of systematic uncertainties in light element abundance estimates on cosmological bounds derivable from Big Bang Nucleosynthesis (BBN) we present tables giving bounds on $\Omega_{baryon}$ and…

天体物理学 · 物理学 2009-10-22 Lawrence M. Krauss , Peter J. Kernan

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…

宇宙学与河外天体物理 · 物理学 2018-09-12 John D. Barrow , Robert J. Scherrer

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…

核理论 · 物理学 2019-06-24 Vinay Singh , Joydev Lahiri , Debasis Bhowmick , D. N. Basu

To constrain the universe before recombination (380000 years after the Big Bang), we mostly rely on the measurements of the primordial abundances that indicate the first insight into the thermal history of the universe. The first production…

宇宙学与河外天体物理 · 物理学 2024-04-30 Tahani Makki , Mounib El Eid , Grant Mathews

Combined with other CMB experiments, the WMAP survey provides an accurate estimate of the baryon density of the Universe. In the framework of the standard Big Bang Nucleosynthesis (BBN), such a baryon density leads to predictions for the…

天体物理学 · 物理学 2009-01-19 Julien Larena , Jean-Michel Alimi , Arturo Serna

We investigate the effects that arise from the inclusion of Weylian boundary terms in the Einstein gravitational field equations in the Big Bang Nucleosynthesis (BBN) framework. With the help of the generalized Friedmann equations for a…

广义相对论与量子宇宙学 · 物理学 2026-04-28 Teodora M. Matei , Cristian Croitoru , Tiberiu Harko

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…

核理论 · 物理学 2024-05-28 Vinay Singh , Debasis Bhowmick , D. N. Basu

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…

天体物理学 · 物理学 2007-05-23 Gary Steigman

Using thermodynamics-gravity conjecture, we present the formal derivation of the modified Friedmann equations inspired by the Barrow entropy, $S\sim A ^{1+\delta/2}$, where $0\leq\delta\leq 1$ is the Barrow exponent and $A$ is the horizon…

广义相对论与量子宇宙学 · 物理学 2025-12-04 Ahmad Sheykhi , Ava Shahbazi Sooraki

Entropic cosmology with the R\'{e}nyi entropy of the apparent horizon $S_R=(1/\alpha)\ln(1+\alpha S_{BH})$, where $S_{BH}$ is the Bekenstein--Hawking entropy, is studied. By virtue of the thermodynamics-gravity correspondence a model of…

综合物理 · 物理学 2026-05-04 S. I. Kruglov

Late-decaying particles naturally arise in many extensions of the Standard Model, directly impacting key cosmological processes in the early universe, such as Big Bang Nucleosynthesis (BBN). BBN studies often consider electromagnetic energy…

高能物理 - 唯象学 · 物理学 2025-01-17 Lucia Angel , Giorgio Arcadi , Matheus M. A. Paixão , Farinaldo S. Queiroz

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…

天体物理学 · 物理学 2007-05-23 Christian Y. Cardall , George M. Fuller

Standard big bang nucleosynthesis (BBNS) promises accurate predictions of the primordial abundances of deuterium, helium-3, helium-4 and lithium-7 as a function of a single parameter. Previous measurements have nearly always been…

天体物理学 · 物理学 2008-02-03 Scott Burles , David Tytler

In the primordial Big Bang nucleosynthesis (BBN), only the lightest nuclides (D, $^3$He, $^4$He, and $^7$Li) were synthesized in appreciable quantities, and these relics provide us a unique window on the early universe. Currently, BBN…

宇宙学与河外天体物理 · 物理学 2014-12-23 J. J. He , S. Q. Hou , A. Parikh , D. Kahl , C. A. Bertulani , other collaborators

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…

天体物理学 · 物理学 2011-02-09 Brian Fields , Subir Sarkar

We consider the implications of the modified dispersion relations, due to the noncommutativity of the spacetime, for a photon gas filling the early Universe in the framework of the Big Bang Nucleosynthesis (BBN) processes, during the period…

广义相对论与量子宇宙学 · 物理学 2026-04-28 Teodora Maria Matei , Cristian Croitoru , Tiberiu Harko
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