# Tag Info

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There shouldn't be any correlation. The CMB light that we see is from a spherical region in the early universe. Its homogeneity strongly suggests that the interior of the sphere was just as homogeneous, but we can't actually see CMB light from the interior. The galaxies that we can see formed from matter inside the sphere, and quite far from the edge. ...

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CMB fluctuations The CMB fluctuations are often analyzed through their power spectrum $P(k)$, which is a measure of the extent to which it is "clumpy" on a given scale $\ell$, with corresponding wavenumber $k = 2\pi/\ell$. The origin of this power spectrum is laid in the very early early Universe, just after the Big Bang, and it is of utmost ...

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Many astronomers and cosmologists conjecture that Population III stars were very massive, perhaps even extremely massive. While this opinion is not universal, it does appear to be dominant. If this is the case, at least some of the very first stars died shortly after they formed, within a million years or less. This in turn would have meant the seeds for the ...

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First off, let us try to clarify a few terms: As usual in astrophysics, metal-free star means atomic number $Z \leq 3$, i.e. it only consists of the primordial elements hydrogen, helium, and lithium. Primordial star literally means original star and refers to the first star(s) (generation) formed after the big bang. It is IMHO equivalent to metal-free, and ...

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Surprisingly, there is no time dilation in the standard FLRW metric that is usually used to model a homogeneous and isotropic universe: $$ds^2 = dt^2 + a(t)d\Omega^2$$ where $t$ is the time, $a(t)$ the scale factor and $d\Omega^2$ the spatial metric. So clocks that are not moving in co-moving coordinated ($d\Omega^2=0$) will not experience gravitational ...

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This Okhubo 2009 paper presents two fiducial models: (a) stars between Pop III-1 stars of 40 to 300 M☉ stars not affected by stellar feedback which end in core-instability SN and BHs [they speculate that some became seeds of SMBHs]; and (b) Pop III-2 stars of 40 to 60 M☉ which do include radiative feedback and explode as Type II SNs, seeding the universe ...

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