“All that Matter … in One Big Bang …”, &Other Cosmological Singularities

Isotropic Cosmological Singularities : Other matter models

Isotropic cosmological singularities are singularities which can be removed by rescaling the metric. In some cases already studied ([2], [1]) existence and uniqueness of cosmological models with data at the sin-gularity has been established. These were cosmologies with, as source, either perfect fluids with linear equations of state or massless, collision-less particles. In this article we cons...

Cosmological perturbations in the 5D Big Bang

evolution. We conclude that, unfortunately, the spectrum is very tilted, with spectral index ns = 3. The amplitude of fluctuations at horizon crossing is given by < (δρ/ρ) >∼ (R0/d)2S−1 E k, where SE 1 is the Euclidean action of the instanton describing the nucleation of a bubble and k is the wavenumber in units of the curvature scale. The spectrum peaks on the smallest possible relevant scale,...

Dark Chocolate and Metabolic Syndrome; Do Polyphenols All that Matter?

Dark Matter and Big Bang Nucleosynthesis

The recently observed Deuterium abundance in a low-metallicity high-redshift hydrogen cloud, which is about ten times larger than that observed in the near interstellar medium, is that expected from the Standard Big Bang Nucleosynthesis theory and the observed abundances of He and Li extrapolated to their primordial values. The inferred cosmic baryon to photon ratio, η = (1.60±0.1)×10, yields a...

Big Bang Nucleosynthesis and Particle Dark Matter

We review how our current understanding of the light element synthesis during the Big Bang Nucleosynthesis era may help shed light on the identity of particle dark matter.