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The determination of the primeval deuterium abundance has opened a precision era in big-bang nucleosynthesis (BBN), making accurate predictions more important than ever before. We present in analytic form new, more precise predictions for…
Deuterium abundances measured recently from QSO absorption-line systems lie in the range from 3 10^{-5} to 3 10^{-4}, which shed some questions on standard big bang theory. We show that this discordance may simply be an artifact caused by…
Big bang nucleosynthesis (BBN) and the cosmic microwave background (CMB) have a long history together in the standard cosmology. The general concordance between the predicted and observed light element abundances provides a direct probe of…
The recent Boomerang and MAXIMA data on the cosmic microwave background suggest a large value for the baryonic matter density of the universe, omega_b = 0.03. This density is larger than allowed by standard big bang nucleosynthesis theory…
Direct observations of the supposedly universal primordial deuterium abundance imply a relatively large baryon density $\Omega_B= (0.019-0.030)h^{-2}$ (95% C.L.). On the other hand, concordance between the previously accepted $^4 He$ and…
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…
The primordial abundances of deuterium, helium, and lithium probe the baryon density of the universe only a few minutes after the Big Bang. Of these relics from the early universe, deuterium is the baryometer of choice. After reviewing the…
Motivated by the recent measurement of the primeval abundance of deuterium, we re-examine the nuclear inputs to big-bang nucleosynthesis (BBN). Using Monte-Carlo realization of the nuclear cross-section data to directly estimate the…
A new observation of D in a primordial gas cloud, made using the high resolution spectrograph at the Keck telescope, indicates an abundance $ D/H =(1.9-2.5) \times 10^{-4}$ \cite{SCHR}. Since deuterium is destroyed by stars, and the…
Zavarygin et al. (2018) compiled a list of 15 deuterium abundance measurements, discarded two because the remaining 13 measurements are then consistent with gaussianity, and found that the weighted mean baryon density (Omega_b h^2)…
The amount of deuterium relative to hydrogen (D/H) in clouds with close to primordial abundance seen at high redshift in the spectra of distant quasars currently provides the best estimate of the baryonic density of the Universe. The first…
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…
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…
Big-bang nucleosynthesis is one of the cornerstones of the standard cosmology. For almost thirty years its predictions have been used to test the big-bang model to within a fraction of a second of the bang. The concordance that exists…
Constraints on big bang nucleosynthesis (BBN) and on cosmological parameters from conflicting deuterium observations in different high red-shift QSO systems are discussed. The high deuterium observations by Carswell et al., Songaila et al.,…
We update Standard Big Bang Nucleosynthesis (SBBN) calculations on the basis of recent nuclear physics compilations (NACRE in particular), experimental and theoretical works. By a Monte--Carlo technique, we calculate the uncertainties on…
The primordial abundance of deuterium produced during Big Bang Nucleosynthesis (BBN) depends sensitively on the universal ratio of baryons to photons, an important cosmological parameter probed independently by the Cosmic Microwave…
Primordial or big bang nucleosynthesis (BBN) is one of the three historical strong evidences for the big bang model. Standard BBN is now a parameter free theory, since the baryonic density of the Universe has been deduced with an…
The primordial abundances of deuterium, helium-3, helium-4, and lithium-7 probe the baryon density of the Universe only a few minutes after the Big Bang. Of these relics from the early Universe, deuterium is the baryometer of choice. After…
Quasar absorption lines now permit a direct probe of deuterium abundances in primordial material, with the best current estimate $ (D/H)=1.9\pm 0.4 \times 10^{-4}$. If this is the universal primordial abundance $(D/H)_p$, Standard Big Bang…