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Related papers: Big Bang nucleosynthesis with a non-Maxwellian dis…

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Primordial or big bang nucleosynthesis (BBN) is now a parameter free theory whose predictions are in good overall agreement with observations. However, the 7Li calculated abundance is significantly higher than the one deduced from…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-20 Alain Coc

Big-bang nucleosynthesis (BBN) is valuable as a means to constrain the physics of the early universe and it is the only probe of the radiation-dominated epoch. A fundamental assumption in BBN is that the nuclear velocity distributions obey…

Nuclear Theory · Physics 2020-06-29 Nishanth Sasankan , Atul Kedia , Motohiko Kusakabe , Grant J Mathews

We show that a class of inhomogeneous big bang nucleosynthesis models exist which yield light-element abundances in agreement with observational constraints for baryon-to-photon ratios significantly smaller than those inferred from standard…

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

Recently we have demostrated that the nonextensitivity parameter q occuring in some applications of Tsallis statistics (known also as index of the corresponding L\'evy distribution) is, in the q>1 case, given entirely by the fluctuations of…

High Energy Physics - Phenomenology · Physics 2007-05-23 G. Wilk , Z. Wlodarczyk

Previous results on Renyi and Wang's formalism of the Tsallis thermostatics are founded by using an extensive variable z connected to the entropic parameter q. It is shown that in the thermodynamical limit both the Tsallis and Renyi…

Statistical Mechanics · Physics 2007-05-23 A. S. Parvan , T. S. Biro

We present a possible extension of the usual relativistic nuclear mean field models widely used to describe nuclear matter towards accounting for the influence of possible intrinsic fluctuations caused by the environment. Rather than…

Nuclear Theory · Physics 2011-04-29 J. Rozynek , G. Wilk

Big Bang Nucleosynthesis (BBN) explores the first few minutes of nuclei formation after the Big Bang. We present updates that result in new constraints at the 2{\sigma} level for the abundances of the four primary light nuclides -…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-20 Michael Foley , Nishanth Sasankan , Motohiko Kusakabe , Grant. J. Mathews

We generalize Hagedorn's statistical theory of momentum spectra of particles produced in high-energy collisions using Tsallis' formalism of non-extensive statistical mechanics. Suitable non-extensive grand canonical partition functions are…

High Energy Physics - Phenomenology · Physics 2009-10-31 Christian Beck

We investigate the constraints that can be set from big-bang nucleosynthesis on two classes of models: extended quintessence and scalar-tensor theories of gravity in which the equivalence principle between standard matter and dark matter is…

Astrophysics · Physics 2010-04-15 Alain Coc , Keith A. Olive , Jean-Philippe Uzan , Elisabeth Vangioni

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

Standard big bang nucleosynthesis (SBBN) has been remarkably successful, and it may well be the correct and sufficient account of what happened. However, interest in variations from the standard picture come from two sources: First, big…

Astrophysics · Physics 2007-05-23 Hannu Kurki-Suonio

The Scale Invariant Vacuum (SIV) paradigm is applied to the Big-Bang Nucleosynthesis using the known analytic expressions for the expansion factor $a$ and the plasma temperature $T$ as functions of the SIV time $\tau$ since the Big-Bang…

Nuclear Theory · Physics 2023-07-11 V. G. Gueorguiev , A. Maeder

We discuss nuclear reactions which could play a role in Big Bang Nucleosynthesis (BBN). Most of these reactions involve lithium and beryllium isotopes and the rates for some of these have not previously been included in BBN calculations.…

Cosmology and Nongalactic Astrophysics · Physics 2010-12-13 Richard N. Boyd , Carl R. Brune , George M. Fuller , Christel J. Smith

I derive completely analytically the time evolution and final abundances of the light elements (up to Be-7) formed in the big-bang nucleosynthesis.This highlights an interesting physics taking place during the formation of light elements in…

Astrophysics · Physics 2009-11-07 V. Mukhanov

We have performed new Big Bang Nucleosynthesis calculations which employ arbitrarily-specified, time-dependent neutrino and antineutrino distribution functions for each of up to four neutrino flavors. We self-consistently couple these…

Astrophysics · Physics 2010-04-30 Christel J. Smith , George M. Fuller , Michael S. Smith

We derive and study quasicanonical Gibbs distribution function which is characterized by the thermostat with finite number of particles (quasithermostat). We show that this naturally leads to Tsallis nonextensive statistics and…

Statistical Mechanics · Physics 2007-05-23 A. K. Aringazin , M. I. Mazhitov

We report the results on Big Bang Nucleosynthesis (BBN) based on an updated code, with accuracy of the order of 0.1% on He4 abundance, compared with the predictions of other recent similar analysis. We discuss the compatibility of the…

Astrophysics · Physics 2009-10-31 S. Esposito , G. Mangano , G. Miele , O. Pisanti

Some results for the black-body radiation obtained in the context of the $q$-thermostatistics are analyzed on both thermodynamical and statistical-mechanical levels. Since the thermodynamic potentials can be expressed in terms of the…

Statistical Mechanics · Physics 2007-05-23 H. Chamati , A. Ts. Djankova , N. S. Tonchev

Big Bang nucleosynthesis (BBN) is the earliest sensitive probe of the values of many fundamental particle physics parameters. We have found the leading linear dependences of primordial abundances on all relevant parameters of the standard…

Astrophysics · Physics 2008-11-26 Thomas Dent , Steffen Stern

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…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Brian D. Fields , Paolo Molaro , Subir Sarkar
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