All Questions
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$Ω = ρ/ρ[c]$, so although near to 1, for an accelerating expansion $Ω$ must be below 1. What's its value?
$Ω$ is taken to have different components - ordinary matter, dark matter, dark energy. But because it is expressed in relation to the critical density for attractive gravity, it seems that omega is ...
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1
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Given current densities of dark energy, dark matter and normal matter in universe currently, calculate ratio of density of dark matter at CMB to now? [closed]
I stumbled upon this question while preparing for the astronomy Olympiad.
It is question #17 in this pdf.
Given that dark energy is vacuum energy, and that the densities of dark energy, dark matter ...
2
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Formula for the bias of galaxies
From the article "Large-Scale Galaxy Bias", I try to deduce the equation that my teacher told me which links 2 quantities:
the global number density of galaxies
the local number density of galaxies
...
user87745
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How do we know that dark matter energy density scales as $\rho\propto a^{-3}$?
How do we know that dark matter energy density scales as $\rho\propto a^{-3}$?
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Average Density of the Universe over Time
For reference:
Referring to a question I posted in Feb. 2015:
Could Hyper-Massive Black Holes be due to Dark Matter in the Early Universe?
User10851 answered, and I replied. He then replied to my ...
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