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Cosmic inventory of energy densities: issues and concerns

T. Padmanabhan
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Abstract

The dynamics of our universe is characterised by the density parameters for cosmological constant ($Ω_V$), nonbaryonic darkmatter($Ω_{\rm wimp}$), radiation ($Ω_R$) and baryons ($Ω_B$). To these parameters -- which describe the smooth background universe -- one needs to add at least another dimensionless number ($\sim 10^{-5}$) characterising the strength of primordial fluctuations in the gravitational potential, in order to ensure formation of structures by gravitational instability. I discuss several issues related to the description of the universe in terms of these numbers and argue that we do not yet have a fundamental understanding of these issues.

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T. Padmanabhan. 2001-12-26. Cosmic inventory of energy densities: issues and concerns. https://arxiv.org/abs/gr-qc/0112068

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