Just a simple explanation please

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The discussion revolves around the age and size of the universe, with estimates suggesting it is between 11 and 20 billion years old and approximately 156 billion light years across. A key point is that the universe can expand faster than the speed of light, allowing for distances greater than 14 billion light years to be observed. Participants clarify that while galaxies move apart, objects like solar systems do not expand with the universe. The confusion arises from understanding that the expansion of space itself does not equate to the movement of objects through space. Ultimately, the expansion of the universe allows for vast distances to be covered without violating the speed of light limit for information transfer.
hedkrash
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Can someone please explain something too me.

From what I understand our current calculations suggest the universe is between 11 and 20 some billion years old.

Astronomers have measured the cosmos to be roughly 156 billion light years across, or 78 billion light years from the outermost edge to the center.

Since nothing can travel faster than light, how could matter have expanded a minimum of 78 billion light years in 11-20 billion years?

Am I missing something?
 
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Yes. You are missing the fact that the universe expands.
 
And the universe can expand faster than light - you just can't send information from one side to the other faster than light. So you can observe anything more than 14Billion light years away.
 
So, in super layman terms...

What was once an centimeter, would now measure a kilometer (if it were possible to observe the universe from the 'outside'). Everything keeps expanding, but since we are part of that expansion, we don't notice it.

Thanks for helping me understand this.
 
hedkrash said:
So, in super layman terms...

Everything keeps expanding, but since we are part of that expansion, we don't notice it.

Be careful of that statement. Objects, say our solar system, earth, you and me, don't expand as part of the expansion. Distance between galaxies *become* further apart. The galaxies themselves don't expand.
 
more confusion

I really thought I had it, alas confusion has set back in.

I can see how the universe could expand faster than the speed of light. If one side was moving away at .9c and the other side moving away at .9c, the combined expansion would be 1.8c away from each other (.8c faster than the speed of light c).

Which means it should still have taken more than 78 billion light years (the distance from the center of the universe to the outermost edge) for the universe to expand as far as it has.

Unless you are suggesting that space itself is expanding, and that expansion doesn't count towards an objects speed.
 

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