Connecting the Galactic and Cosmological Scales: Dark Energy and the Cuspy-Core Problem

A. D. Speliotopoulos

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arXiv · 0712.0216

Connecting the Galactic and Cosmological Scales: Dark Energy and the Cuspy-Core Problem

A. D. Speliotopoulos

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Abstract

We propose a solution to the `cuspy-core' problem by extending the geodesic equations of motion using the Dark Energy length scale $λ_{DE}=c/(Λ_{DE} G)^{1/2}$. This extension does not affect the motion of photons; gravitational lensing is unchanged. A cosmological check of the theory is made, and $σ_8$ is calculated to be $0.68_{\pm0.11}$, compared to $0.761_{-0.048}^{+0.049}$ for WMAP. We estimate the fractional density of matter that cannot be determined through gravity at $0.197_{\pm 0.017}$, compared to $0.196^{+0.025}_{-0.026}$, the fractional density of nonbaryonic matter. The fractional density of matter that can be determined through gravity is estimated at $0.041_{-0.031}^{+0.030}$, compared to $0.0416_{-0.0039}^{+0.0038}$ for $Ω_B$.

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A. D. Speliotopoulos. 2007-12-03. Connecting the Galactic and Cosmological Scales: Dark Energy and the Cuspy-Core Problem. https://arxiv.org/abs/0712.0216

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