What Happens to the Universe if Omega Equals Exactly 1?

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If Omega equals exactly 1, the universe's fate is debated, as it cannot end in a big crunch or a big freeze. Instead, it would reach a state of asymptotic stationarity, expanding forever at a decreasing rate if no dark energy is present. However, current theories suggest that while Omega is approximately 1, the universe is dominated by dark energy, leading to accelerated expansion. This means that in practical terms, both Omega equal to 1 and less than 1 result in a scenario where the universe expands indefinitely. The discussion highlights the complexities and paradoxes surrounding the implications of Omega's value.
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If Omega was exactly 1...

We know if the value of omega (the average mass of all matter int he universe was) was more than 1, the ultimate fate of our universe is the big crunch; also if omga was less than one, there wouldn't be enough gravitational pull to bring all matter back, however will expand forever, and will end in a big freeze.
I'm thinking if Omega was exactly 1, what's the final fate, it can't end in a crunch, or a freeze, or it can't be exactly one. It'll have to be a midway point between a freeze and a crunch, this can be used as a paradox, as there is no logical answer to my knowledge.
 
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If \Omega_m=1 and there's no dark energy or cosmological constant, then the universe asymptotically approaches stationarity as time approaches infinity. In other words, it expands forever, but at an ever slower rate. However, the most popular theory of the universe right now gives the following:

\Omega = 1

\Omega_m \simeq 0.3

\Omega_{\Lambda} \simeq 0.7

That is, we think that \Omega = 1, but the dominant component has a negative pressure. In this scenario, we expect the universe to expand forever and at an accelerated rate.
 
So, for all practical purposes :wink: and ignoring Dark Energy, omega =1 and < 1 gives you the same end-of-universe scenario.

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o I am sorry I was referring to the value of lambda and omega as one...:smile:
 
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