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 'Hubble Constant, Dark Energy and the Expanding Universe'

Why was the Hubble constant assumed to be decreasing and slowing down (decelerating) the expansion rate of the Universe, while at the same time Dark Energy is presumably accelerating the expansion? And to thicken the plot. recent news from NASA indicates that the Hubble constant is now increasing. Can you clarify this enigma? Also., if the Hubble constant eventually decreases, why is there a lower limit to its value?
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