English
Related papers

Related papers: A linear programming approach to inhomogeneous pri…

200 papers

In a previous paper (Serna & Alimi 1996), we have pointed out the existence of some particular scalar-tensor gravity theories able to relax the nucleosynthesis constraint on the cosmic baryonic density. In this paper, we present an…

Astrophysics · Physics 2009-10-30 Jean-Michel Alimi , Arturo Serna

We investigate the effects of baryon/anti-baryon inhomogeneity on primordial nucleosynthesis. Recent work claims that electroweak baryogenesis could give rise to distinct regions of net baryon and anti-baryon number, which could survive…

Astrophysics · Physics 2007-05-23 Kevork Abazajian , George M. Fuller

We have recently considered cosmologies in which the Universal scale factor varies as a power of the age of the Universe and concluded that they cannot satisfy the observational constraints on the present age, the magnitude-redshift…

Astrophysics · Physics 2009-10-31 M. Kaplinghat , G. Steigman , T. P. Walker

We consider inhomogeneous big bang nucleosynthesis in light of the present observational situation. Different observations of He-4 and D disagree with each other, and depending on which set of observations one uses, the estimated primordial…

Astrophysics · Physics 2009-10-30 K. Kainulainen , H. Kurki-Suonio , E. Sihvola

Recent observation of the power spectrum of Cosmic Microwave Background (CMB) Radiation has exhibited that the flat cosmology is most likely. This suggests too large universal baryon-density parameter $\Omega_b h^2 \approx 0.022 \sim 0.030$…

Astrophysics · Physics 2007-05-23 Toshitaka Kajino

Comparing the latest observed abundances of 4He and D, we make a ?2 analysis to see whether it is possible to reconcile primordial nucleosynthesis using up-to-date nuclear data of NACRE II and the mean-life of neutrons. If we adopt the…

Cosmology and Nongalactic Astrophysics · Physics 2014-08-05 R. Ichimasa , R. Nakamura , M. Hashimoto , K. Arai

This paper proposes a model, the linear model, for randomly generating logic programs with low density of rules and investigates statistical properties of such random logic programs. It is mathematically shown that the average number of…

Artificial Intelligence · Computer Science 2015-10-07 Kewen Wang , Lian Wen , Kedian Mu

We discuss the primordial nucleosynthesis in lepton asymmetric Universe models. In order to better estimate the universal baryon-mass density parameter $\Omega_b$, we try to remove the uncertainty from the theoretical prediction of…

Astrophysics · Physics 2007-05-23 T. Kajino , T. -K. Suzuki , S. Kawanomoto , H. Ando

We study big bang nucleosynthesis in the presence of large mass-scale, non-linear entropy fluctuations. Overdense regions, with masses above the local baryon-Jeans mass, are expected to collapse and form condensed objects. Surviving…

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

We study the impact of possible high density baryonic bubbles on the early formed QSO, IGM, and metal poor stars. Such bubbles could be created, under certain conditions, in Affleck-Dine model of baryogenesis and may occupy a relatively…

Astrophysics · Physics 2009-11-10 Shunji Matsuura , Alexander. D. Dolgov , Shigehiro Nagataki , Katsuhiko Sato

We present a detailed study of inhomogeneous Big Bang nucleosynthesis where, for the first time, nuclear reactions are coupled to all significant fluctuation dissipation processes. Theses processes include neutrino heat transport, baryon…

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

We consider the effect of inhomogeneous neutrino degeneracy on Big Bang nucleosynthesis for the case where the distribution of neutrino chemical potentials is given by a Gaussian. The chemical potential fluctuations are taken to be…

Astrophysics · Physics 2009-11-07 Spencer D. Stirling , Robert J. Scherrer

In this study, the theoretical maximum efficiency $\eta_{max}$ and the Boltzmann-type factor giving the concentration ratio of excited-to-ground state pigment-molecules for photosynthetic systems under irradiation with arbitrary photon flux…

Statistical Mechanics · Physics 2025-12-17 Tetsuo Yabuki

Let $P = \{p(i)\}$ be a measure of strictly positive probabilities on the set of nonnegative integers. Although the countable number of inputs prevents usage of the Huffman algorithm, there are nontrivial $P$ for which known methods find a…

Information Theory · Computer Science 2007-07-13 Michael B. Baer

We clarify how intense laser irradiation leads to an enhancement of rare processes that may occur within atoms. Non-perturbative calculation using a coherent laser beam gives an exact, time dependent formula of the enhancement factor in the…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. Yoshimura

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

We present a model for big bang nucleosynthesis which combines baryon inhomogeneities with the effects of the decays of massive particles (masses higher than a few GeV). Those particles, with half-lives longer than the standard…

Astrophysics · Physics 2007-05-23 J. Lopez-Suarez , R. Canal

We have calculated the small effect of finite nucleon mass on the weak-interaction rates that interconvert protons and neutrons in the early Universe. We have modified the standard code for primordial nucleosynthesis to include these…

Astrophysics · Physics 2009-12-30 Robert E. Lopez , Michael S. Turner , Geza Gyuk

We extend the model-independent likelihood analysis of big bang nucleosynthesis (BBN) based on He4 and Li7 to allow for numbers of degrees of freedom which differ from the standard model value characterized by $N_\nu = 3$. We use the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Keith A. Olive , David Thomas

We present a study of inhomogeneous big bang nucleosynthesis with emphasis on transport phenomena. We combine a hydrodynamic treatment to a nuclear reaction network and compute the light element abundances for a range of inhomogeneity…

Astrophysics · Physics 2016-08-30 Elina Keihanen