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Related papers: Bit-String Physics Prediction of eta, The Dark Mat…

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A decade ago bit-string physics predicted that the baryon/photon ratio at the time of nucleogenesis $\eta= 1/256^4$ and that the dark matter/baryonic matter ratio $\Omega_{DM}/\Omega_B= 12.7$. Accepting that the normalized Hubble constant…

Astrophysics · Physics 2007-05-23 H. Pierre Noyes

Since the baryon-to-photon ratio "eta" is in some doubt at present, we ignore the constraints on eta from big bang nucleosynthesis (BBN) and fit the three key cosmological parameters (h, Omega_M, eta) to four other observational…

Astrophysics · Physics 2022-03-23 G. Steigman , N. Hata , J. E. Felten

Because the baryon-to-photon ratio eta_{10} is in some doubt, we drop nucleosynthetic constraints on eta_{10} and fit the three cosmological parameters (h, Omega_M, eta_{10}) to four observational constraints: Hubble parameter h_o =…

Astrophysics · Physics 2009-10-30 G. Steigman , N. Hata , J. E. Felten

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

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…

Astrophysics · Physics 2011-02-09 Brian Fields , Subir Sarkar

Measurements of the Cosmic Microwave Background Radiation (CMBR) provide a powerful tool for measuring the primary cosmological parameters. However, there is a large degree of parameter degeneracy in simultaneous measurements of the matter…

Astrophysics · Physics 2016-08-30 Steen Hannestad

Cosmic microwave background (CMB) determinations of the baryon-to-photon ratio $\eta \propto \Omega_{\rm baryon} h^2$ will remove the last free parameter from (standard) big bang nucleosynthesis (BBN) calculations. This will make BBN a much…

Astrophysics · Physics 2008-11-26 Richard H. Cyburt , Brian D. Fields , Keith A. Olive

The BBN predictions for the abundances of the light element isotopes is reviewed and compared with recent observational data. The single unknown parameter of standard BBN is the baryon-to-photon ratio, \eta, and can be determined by the…

Astrophysics · Physics 2017-08-23 Keith A. Olive

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…

Astrophysics · Physics 2007-05-23 Brian Fields , Subir Sarkar

Following a brief introduction to early Universe cosmology, the current of status of big bang nucleosynthesis is reviewed and the concordance between theory and observation is examined in detail. The abundances of He4 and Li7 determine the…

Astrophysics · Physics 2007-05-23 Keith A. Olive

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

We examine inhomogeneous primordial nucleosynthesis for {\it arbitrary} distributions $f$ of the baryon-to-photon ratio $\eta$, in the limit where neither particle diffusion nor gravitational collapse is important. By discretizing $f(\eta)$…

Astrophysics · Physics 2016-08-30 Richard E. Leonard , Robert J. Scherrer

We compute the joint constraints on ten cosmological parameters from the latest CMB measurements. The lack of a significant second acoustic peak in the latest Boomerang and Maxima data favors models with more baryons than Big Bang…

Astrophysics · Physics 2009-10-07 Max Tegmark , Matias Zaldarriaga

For decades, the determination of the mean density of matter(Omega_M) has been tied to the distribution of light. This has led to a ``bias,'' perhaps as large as a factor of 2, in determining a key cosmological parameter. Recent…

Astrophysics · Physics 2011-05-12 Michael S. Turner

In this paper we show that the baryon-to-photon ratio $\eta$ is in general not conserved before decoupling in non-minimally coupled theories of gravity. We use big-bang nucleosynthesis and cosmic microwave background limits on the…

General Relativity and Quantum Cosmology · Physics 2018-10-03 R. P. L. Azevedo , P. P. Avelino

Recent improvements in astronomical observations lead to the conclusion that the Hubble constant lies between 60 and 80 Mpc km$^{-1}$ sec$^{-1}$ and the age of the universe between 11 and 14 Gigayears. Taken together with recent…

General Relativity and Quantum Cosmology · Physics 2007-05-23 H. Pierre Noyes

The primordial abundance of $^4$He plays a central role in big-bang nucleosynthesis (BBN) and in the cosmic microwave background (CMB). The LBT $Y_{\rm p}$ Project's new measurement of the primordial $^4$He mass fraction $Y_{\rm p} =0.2458…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-02 Tsung-Han Yeh , Keith A. Olive , Brian D. Fields , Erik Aver , Richard W. Pogge , Noah S. J. Rogers , Evan D. Skillman , Miqaela K. Weller

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…

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

By taking seriously the limits on observability which come from combining relativistic quantum mechanics with general relativity, Ed Jones has shown that the current measurements of the cosmological constant density $\Omega_{\Lambda}\sim…

Astrophysics · Physics 2007-05-23 H. Pierre Noyes , Louis H. Kauffman , James V. Lindesay , Walter R. Lamb

We use Big Bang Nucleosynthesis calculations and light element abundance data to constrain the relative variation of the deuteron binding energy since the universe was a few minutes old, $\delta Q = Q(BBN)-Q(present)$. Two approaches are…

Astrophysics · Physics 2009-08-18 V. F. Dmitriev , V. V. Flambaum , J. K. Webb
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