(adsbygoogle = window.adsbygoogle || []).push({}); CMB fluctuations and large scale fluctuations nowadays do not match ???

The CMB dark matter density fluctuations for big scales is d_rho/rho~ 10^-5 and lower.

The scale factor increased ~ 1000 times from last scattering to now.

Linear perturbation theory predicts that the density fluctuations today would be ~ 1000 times what they were at last scattering i.e. d_rho/rho ~ 10^-2 today.

That is in obvious disagreement with what we observe since density fluctuations on scales of voids for example suggest fluctuations of order d_rho/rho ~ 1. This is two orders of magnitudes off the suggested value from linear perturbation theory and such big scales like voids just entered the non-linear regime so the explanation it's nonlinear effect is not plausable.

So what is the explanation of that?

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# CMB fluctuations and large scale fluctuations nowadays do not match ?

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