Semi-analytical Analysis of Helium Synthesis in Brane Cosmology
نویسندگان
چکیده
The problem of primordial nucleosynthesis of helium in brane cosmology is studied using a semi-analytical method, where the Fermi-Dirac statistic is ignored. This semi-analytical method agrees with a more complete numerical calculation with a precision of order of 10% or better. The quadratic term for the matter density is the only source considered in the modified Einstein equations predicted by the brane configuration. This hypothesis is justified a posteriori. An agreement between theoretical and observational values for the helium abundance is obtained if the fundamental mass scale in five dimensions is of the order of M ∼ 5× 10 GeV . PACS numbers: 98.80.Ft, 26.35.+c
منابع مشابه
Cosmology in a non-standard statistical background
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 densities in the early universe are obtained and their consequences on the Helium synthesis are analized. We find that, if the nucleosynthesis scenario should be in ...
متن کاملSpherically Symmetric Solutions in a New Braneworld Massive Gravity Theory
In this paper, a combination of the braneworld scenario and covariant de Rham-Gabadadze-Tolley (dRGT) massive Gravity theory is proposed. In this setup, the five-dimensional bulk graviton is considered to be massive. The five dimensional nonlinear ghost-free massive gravity theory affects the 3-brane dynamics and the gravitational potential on the brane. Following the solutions with spherical s...
متن کاملLiving on the edge: cosmology on the boundary of anti-de Sitter space
We sketch a particularly simple and compelling version of D-brane cosmology. Inspired by the semi-phenomenological Ž . Randall–Sundrum models, and their cosmological generalizations, we develop a variant that contains a single 3q1 Ž . dimensional D-brane which is located on the boundary of a single bulk 4q1 -dimensional region. The D-brane boundary is Ž . itself to be interpreted as our visible...
متن کاملBirth of the Brane Universe
Quantum cosmology of the brane universe is studied. It is shown that an inflating brane universe can be created from nothing and the wave function of the universe and the time-dependent Schrödinger equation for quantized scalar fields are the same as those obtained in the conventional 4-dimensional quantum cosmology if the bulk is exactly the Anti-de Sitter spacetime. The effect of the massive ...
متن کاملLimits on the integration constant of the dark radiation term in Brane Cosmology
We consider the constraints from primordial Helium abundances on the constant of integration of the dark radiation term of the brane-world generalized Friedmann equation derived from the Randall-Sundrum Single brane model. We found that – using simple, approximate and semianalytical Method – that the constant of integration is limited to be between -8.9 and 2.2 which limits the possible contrib...
متن کامل