Is the Universe Truly Expanding? Examining the Paradox of Infinite Expansion

AI Thread Summary
The discussion centers on the paradox of an expanding universe in relation to its potential infinitude. Some participants argue that while the universe may be infinite, its expansion is not contradictory. The concept of infinity is explored to illustrate that an infinite set can still experience expansion. An analogy is provided comparing two infinite sets to clarify this point. The conversation ultimately emphasizes the complexity of understanding the universe's expansion in the context of infinity.
Ben.meyer
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I have been looking around people are talking about the universe expanding. By geometry we are able to figure out that the universe is infinite. The question is, if the universe is infinite than how can be expanding?
 
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Ben.meyer said:
I have been looking around people are talking about the universe expanding. By geometry we are able to figure out that the universe is infinite. The question is, if the universe is infinite than how can be expanding?

No, we are NOT able to calculate that the universe is infinite. It MIGHT be, or it might not be.

Regardless, if it IS infinite, then continued expansion is not a problem.

You should read up on the concept of infinity.
 
Imagine I have a set 1,2,3,4,5,6,...

Then some later time that set has now 2,4,6,8,10,12,...

Both sets are infinite, but in some sense that set has expanded.
 
Thanks, that definately gave me a better understanding.
 

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