Stability of cosmological models

AI Thread Summary
The discussion centers on the formation of large-scale structures in stable cosmological models, specifically questioning the assertion that such structures cannot arise in these models. One participant references a paper by Wanas and Bakry, which claims that stable cosmological models do not support large-scale structures. Another participant argues that this claim is overly broad, suggesting that it should specify models stable against gravitational or curvature perturbations, like the Einstein static universe. The debate highlights differing interpretations of stability in cosmology and its implications for structure formation. Ultimately, the conversation seeks to clarify the conditions under which large-scale structures can exist in cosmological models.
axlsaml1
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to those experts in the field of cosmology

i was wondering if " large scale structures can be formed in stable cosmological models"

or should i say that " large scale structures cannot be formed in those cosmological models that are stable with respect to gravitational or other curvature perturbations like the Einstein static universe model "
 
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Hmm, this sounds like a homework question.

What are your thoughts on this? Generally homework help is given only if the genuine attempts made have been shown in the post. There is also a specific homework help forum, although for cosmology you might get better results here, but you still need to show your work on the question first!

Welcome to PF!
 
hint : Wanas and Bakry in a paper entitled " stability of cosmological models"


say : that large scale structures cannot be formed in stable cosmological models.

i just don't agree and i say that their argument is not accurate enough . i think they shoul rather say :

that " large scale structures cannot be formed in those cosmological models that are stable with respect to gravitational or other curvature perturbations like the Einstein static universe model "

who's wrong ?
I or them?
 
But why do you disagree? What is wrong about what they say?
 
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