Can a closed universe expand forever?

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A closed universe is typically expected to collapse, but recent observations suggest it may continue expanding indefinitely. The possibility of a closed universe expanding forever hinges on its geometry. An analogy is drawn with a balloon, which can expand endlessly unless it bursts. This raises questions about the nature of a closed universe and whether it can sustain perpetual expansion. The discussion emphasizes the importance of understanding cosmic geometry in determining the fate of the universe.
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Most say that a closed universe would collapse. Recent observations show that the universe will probably keep on expanding forever. Does this mean we cannot live in a closed universe? Or, is there a loop hole which allows a closed universe to expand forever?
 
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It depends on the geometry of the universe. 2-d analog: blow up a balloon and the surface can expand forever (unless it breaks).
 

Thread 'Matter density right after the decoupling'

https://en.wikipedia.org/wiki/Recombination_(cosmology) Was a matter density right after the decoupling low enough to consider the vacuum as the actual vacuum, and not the medium through which the light propagates with the speed lower than ##({\epsilon_0\mu_0})^{-1/2}##? I'm asking this in context of the calculation of the observable universe radius, where the time integral of the inverse of the scale factor is multiplied by the constant speed of light ##c##.
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Thread 'Rutgers finds a transparent Einstein Cross - apparently a dark matter "halo".'

The formal paper is here. The Rutgers University news has published a story about an image being closely examined at their New Brunswick campus. Here is an excerpt: Computer modeling of the gravitational lens by Keeton and Eid showed that the four visible foreground galaxies causing the gravitational bending couldn’t explain the details of the five-image pattern. Only with the addition of a large, invisible mass, in this case, a dark matter halo, could the model match the observations...
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Thread 'Big Bang and Infinite Universe'

Hi, I’m pretty new to cosmology and I’m trying to get my head around the Big Bang and the potential infinite extent of the universe as a whole. There’s lots of misleading info out there but this forum and a few others have helped me and I just wanted to check I have the right idea. The Big Bang was the creation of space and time. At this instant t=0 space was infinite in size but the scale factor was zero. I’m picturing it (hopefully correctly) like an excel spreadsheet with infinite...
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