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Related papers: Barrow Cosmology and Big-Bang Nucleosynthesis

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The Barrow entropy appears from the fact that the black hole surface can be modified due to quantum gravitational outcome. The measure of this perturbation is given by a new exponent $\Delta$. In this letter we have shown that, from the…

General Relativity and Quantum Cosmology · Physics 2020-08-26 Everton M. C. Abreu , Jorge Ananias Neto , Edésio M. Barboza

This paper derives an upper limit on the density $\rho_{\scriptstyle\Lambda}$ of dark energy based on the requirement that cosmological structure forms before being frozen out by the eventual acceleration of the universe. By allowing for…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-22 Fred C. Adams , Stephon Alexander , Evan Grohs , Laura Mersini-Houghton

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…

High Energy Physics - Phenomenology · Physics 2025-01-17 Lucia Angel , Giorgio Arcadi , Matheus M. A. Paixão , Farinaldo S. Queiroz

In this work, a new generic parameterisation for $f(R)$ theories is presented. Our proposal for a new equation of state can reproduce an $f(R)$-like evolution that describes late and early time universe within 1-$\sigma$ C.L when we use a…

General Relativity and Quantum Cosmology · Physics 2020-11-20 N. M. Jiménez Cruz , Celia Escamilla-Rivera

In this work, we derive a generalized modified Friedmann equation based on an entropy-area relation that incorporates established modifications, such as volumetric, linear, and logarithmic terms, in addition to novel entropic modifications…

General Relativity and Quantum Cosmology · Physics 2024-12-17 Javier Chagoya , I. Díaz-Saldaña , Mario H. Amante , J. C. López-Domínguez , M. Sabido

We calculate the amount of primordial matter density contrast and the size of the very early universe in the recent Quantum Big Bang theory [arXiv:0705.4549 [gr-qc](2007)] of the cosmological constant. We obtain $(\delta\rho/\rho)_M = 1.75…

General Relativity and Quantum Cosmology · Physics 2009-11-13 Budh Ram

We discuss a constraint on the scale $\Lambda_{\rm NC}$ of noncommutative (NC) gauge field theory arising from consideration of the big bang nucleosynthesis (BBN) of light elements. The propagation of neutrinos in the NC background…

High Energy Physics - Phenomenology · Physics 2014-11-18 Raul Horvat , Josip Trampetic

The cosmic energy density in the form of radiation before and during Big Bang Nucleosynthesis (BBN) is typically parameterized in terms of the effective number of neutrinos N_eff. This quantity, in case of no extra degrees of freedom,…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 G. Mangano , G. Miele , S. Pastor , O. Pisanti , S. Sarikas

Primordial or Big Bang nucleosynthesis (BBN) is one of the three historical strong evidences for the Big-Bang model together with the expansion of the Universe and the Cosmic Microwave Background radiation (CMB). The recent results by the…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-29 Alain Coc , Jean-Philippe Uzan , Elisabeth Vangioni

Primordial nucleosynthesis provides a probe of the Universe during its early evolution. Given the progress exploring the constituents, structure, and recent evolution of the Universe, it is timely to review the status of Big Bang…

Astrophysics · Physics 2009-06-23 Gary Steigman

A key pillar of modern cosmology, Big Bang Nucleosynthesis (BBN) offers a probe of the particle content and expansion rate of the Universe a mere few minutes after the beginning. When compared with the BBN predictions, the observationally…

Astrophysics · Physics 2007-05-23 Gary Steigman

We construct Barrow holographic dark energy in the case of non-flat universe. In particular, considering closed and open spatial geometry we extract the differential equations that determine the evolution of the dark-energy density…

General Relativity and Quantum Cosmology · Physics 2021-11-01 Priyanka Adhikary , Sudipta Das , Spyros Basilakos , Emmanuel N. Saridakis

The primordial abundances of the light nuclides produced by Big Bang Nucleosynthesis (BBN) during the first 20 minutes in the evolution of the Universe are sensitive to the universal density of baryons and to the expansion rate of the early…

High Energy Physics - Phenomenology · Physics 2007-05-23 Gary Steigman

We present a multi-epoch test of f(T) gravity with nonminimal torsion-matter coupling, combining early- and late-Universe observations. At the MeV scale, Big-Bang Nucleosynthesis constrains the fractional variation of the weak freeze-out…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-27 Yahia Al-Omar , Majida Nahili , Nidal Chamoun

We analyze the observational constraints on brane-world cosmology whereby the universe is described as a three-brane embedded in a five-dimensional anti-de Sitter space. In this brane-universe cosmology, the Friedmann equation is modified…

Astrophysics · Physics 2009-11-07 K. Ichiki , M. Yahiro , T. Kajino , M. Orito , G. J. Mathews

A host of dark energy models and non-standard cosmologies predict an enhanced Hubble rate in the early Universe: perfectly viable models, which satisfy Big Bang Nucleosynthesis (BBN), cosmic microwave background and general relativity…

High Energy Physics - Phenomenology · Physics 2009-11-11 M. Schelke , R. Catena , N. Fornengo , A. Masiero , M. Pietroni

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…

General Relativity and Quantum Cosmology · Physics 2026-04-28 Teodora Maria Matei , Cristian Croitoru , Tiberiu Harko

We derive exact theoretical value of the constant cosmic background radiation (CBR) temperature $T_0$ using the interconnections between the Gamow, Alpher and Herman (GAH) hot Big Bang cosmology model of the expanding Universe and the…

General Physics · Physics 2010-12-06 Asger G. Gasanalizade

We include correlations between elemental abundances in a Monte Carlo statistical analysis of BBN predictions, which, along with updated reaction rates and an improved BBN code, lead to tightened constraints on $\Omega_{B}$ and $N_{\nu}$.…

Astrophysics · Physics 2009-10-22 Peter J. Kernan , Lawrence M. Krauss

This paper continues the building of the cosmological theory that was introduced in two earlier papers under the title A Dust Universe Solution to the Dark Energy Problem. The model introduced in this theory has existence before time zero…

General Physics · Physics 2010-02-21 James G. Gilson