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Related papers: Cosmological Lithium Problems

200 papers

We point out that the cosmological abundance of ${}^7$Li can be reduced down to observed values if during its formation Big Bang Nucleosynthesis is modified by the presence of light electrically neutral particles $X$ that have substantial…

High Energy Physics - Phenomenology · Physics 2016-06-01 Andreas Goudelis , Maxim Pospelov , Josef Pradler

Big Bang nucleosynthesis (BBN) theory predicts the abundances of the light elements D, $^3$He, $^4$He and $^7$Li produced in the early universe. The primordial abundances of D and $^4$He inferred from observational data are in good…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-17 S. Q. Hou , J. J. He , A. Parikh , D. Kahl , C. A. Bertulani , T. Kajino , G. J. Mathews , G. Zhao

In these Lectures I review possible constraints on particle physics models, obtained by means of combining the results of collider measurements with astrophysical data. I emphasize the theoretical-model dependence of these results. I…

High Energy Physics - Phenomenology · Physics 2017-08-23 Nikolaos E. Mavromatos

According to the standard models of particle physics and cosmology, there should be a background of cosmic neutrinos in the present Universe, similar to the cosmic microwave photon background. The weakness of the weak interactions renders…

High Energy Physics - Phenomenology · Physics 2013-05-27 Gary Steigman

We study the primordial neutron to baryon ratio in a cosmological expanding background within the context of non-extensive statistics, in a fully analytical approach. First order corrections to the weak interaction rates and energy…

Astrophysics · Physics 2015-06-24 Diego F. Torres , Hector Vucetich

In a recent article R. T. Cahill claims that the cosmological model based on his "new physics of a dynamical 3-space" resolves the CMB-BBN Lithium-7 and Helium-4 abundance anomalies. In this note it is shown that this conclusion is wrong,…

General Physics · Physics 2010-02-26 Gary Steigman

Standard Big Bang nucleosynthesis at baryonic density as inferred by WMAP implies a primordial Li7 abundance factor of two to three larger than that inferred by observations of low--metallicity halo stars. Recent observations of Li6 in halo…

High Energy Physics - Phenomenology · Physics 2009-11-11 Karsten Jedamzik , Ki-Young Choi , Leszek Roszkowski , Roberto Ruiz de Austri

The lectures describe several cosmological effects produced by neutrinos. Upper and lower cosmological limits on neutrino mass are derived. The role that neutrinos may play in formation of large scale structure of the universe is described…

High Energy Physics - Phenomenology · Physics 2010-12-09 A. D. Dolgov

Recent measurements of cosmic-ray electron and positron fluxes by PAMELA and ATIC experiments may indicate the existence of annihilating dark matter with large annihilation cross section. We show that the dark matter annihilation in the…

High Energy Physics - Phenomenology · Physics 2010-04-21 Junji Hisano , Masahiro Kawasaki , Kazunori Kohri , Takeo Moroi , Kazunori Nakayama

The cosmological abundance of nucleons determined from considerations of Big Bang nucleosynthesis allegedly provides compelling evidence for non-nucleonic dark matter. Recent developments in measurements of primordial light element…

Astrophysics · Physics 2007-05-23 Subir Sarkar

It will be shown that a given realization of nonlinear electrodynamics, used as source of Einstein's equations, generates a cosmological model with interesting features, namely a phase of current cosmic acceleration, and the absence of an…

General Relativity and Quantum Cosmology · Physics 2008-11-26 M. Novello , E. Goulart , J. M. Salim , S. E. Perez Bergliaffa

We derive general constraints on the relic abundances of a long-lived particle which mainly decays into a neutrino (and something else) at cosmological time scales. Such an exotic particle may show up in various particle-physics models…

High Energy Physics - Phenomenology · Physics 2008-11-26 Toru Kanzaki , Masahiro Kawasaki , Kazunori Kohri , Takeo Moroi

Primordial nucleosynthesis remains as one of the pillars of modern cosmology. It is the testing ground upon which many cosmological models must ultimately rest. It is our only probe of the universe during the important radiation-dominated…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-20 Grant J. Mathews , Motohiko Kusakabe , Toshitaka Kajino

Non-extensive statistics, namely Tsallis statistics, is applied on a case of a supercritical string cosmology and interesting cosmological modifications are obtained. The two main results we focus on in this work are: fractal scaling for…

High Energy Physics - Theory · Physics 2009-08-07 Ariadne Vergou

The good agreement between large-scale observations and the predictions of the now-standard $\Lambda$CDM theory gives us hope that this will become a lasting foundation for cosmology. After briefly reviewing the current status of the key…

Astrophysics · Physics 2011-08-23 Joel R. Primack

The cosmological recombination history of lithium, produced during Big--Bang nucleosynthesis, is presented using updated chemistry and cosmological parameters consistent with recent cosmic microwave background (CMB) measurements. For the…

Astrophysics · Physics 2009-11-07 P. C. Stancil , A. Loeb , M. Zaldarriaga , A. Dalgarno , S. Lepp

We review the current cosmological status of neutrinos, with particular emphasis on their effects on Big Bang Nucleosynthesis, Large Scale Structure of the universe and Cosmic Microwave Background Radiation measurements.

Astrophysics · Physics 2009-11-13 Ofelia Pisanti , P. D. Serpico

Cosmological implications of neutrinos are reviewed. The following subjects are discussed at a different level of scrutiny: cosmological limits on neutrino mass, neutrinos and primordial nucleosynthesis, cosmological constraints on unstable…

High Energy Physics - Phenomenology · Physics 2009-11-07 A. D. Dolgov

We consider different aspects of the problem of cosmological singularity such as the BKL oscillatory approach to the singularity, the new features of the cosmological dynamics in the neighbourhood of the singularity in multidimensional and…

General Relativity and Quantum Cosmology · Physics 2010-12-17 A. Yu. Kamenshchik

A brief survey of nuclide abundances in the solar-system and in cosmic rays and of the believed mechanisms of their synthesis is given. The role of spallation processes in nucleosynthesis is discussed. A short review of recent measurements,…

Astrophysics · Physics 2007-05-23 Stepan G. Mashnik