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Actually I think you cleared it up for me without my going to the link. I have heard that explanation before but not in the context of answering the question I asked. That would mean that from the center of the Big Bang to the surface of the balloon would essentially be devoid of material since it was all blasted away at the same time by the same force. Right?

This also means that farther objects are unreachable and unknowable to us at this time; the light from them is still traveling toward us.

How would that necessarily be so? If light emitting objects existed further than 13 billion light years away yet have existed longer than 13 b. years then the light could be reaching us now. Say; an object 20 b. light years away that has existed for 30 b. years. No?

The rubber of the balloon skin represents the entire knowable universe in all its multiple dimensions.

Imagine (if you will) a balloon made of very thick rubber. This rubber has been printed or doped with a special technique so that it has pictures of stars and galaxies within it.

When the balloon is blown up: imagine that not only the balloon expands, but the thick rubber skin expands ‘sideways’.

That’s the model. Space expanding in all directions and everything IN space - the stars and galaxies - getting further apart.

But don’t think about the space inside the balloon. That isn’t part of the analogy anymore than the air-pump blowing up the balloon is.

Hope this is helpful.

That would mean that from the center of the Big Bang to the surface of the balloon would essentially be devoid of material since it was all blasted away at the same time by the same force. Right?

I'm not a professional cosmologist, but - as I understand it - we don't care if there is any material "farther" from the imaginary inflating shell, or closer to the "center" (whatever those words mean - we must understand that time and space were created in the Big Bang^[1].) Bake a loaf of bread with raisins. As the dough rises, all raisins move away from each other; but any two raisins don't care what other raisins are doing - they aren't affected by that. Similarly, dots on a balloon don't care if there are larger balloons outside or smaller balloons inside.

Yes, with one little catch - the age of Universe is about 13 billion years. So if there is an object 20 billion light years away it can exist only for 13 billion years (even if we assume that it got there instantly^[2]) and therefore we have to wait another 7 billion years until the light from it reaches us.

In other words, there is no object in this Universe that is older than the Universe itself, and as result we can't see past the point of birth of the Universe.

^[1]Imagine a water insect that can only live on the boundary of water and air. Take a sealed barrel of water. Can such an insect live anywhere in it? No, because there is no boundary - there is only water in it.

Now heat the barrel until bubbles of steam are released. Now you have the boundary, and as long as those bubbles last long enough you just created a bunch of Universes for little 2D civilizations of water spiders to sprout, eventually. And if you rework the whole model one dimension higher you can see how our 3D Universe could "condensate" out of space with higher dimensions.

^[2] How could that be? A 2D analogy may help. We know that if you drop a stone into water a circular wave will start spreading, relatively slowly. A water insect, being a 2D creature, can't imagine how something (a wave) can instantly appear everywhere; the insect expects it to originate somewhere and then propagate somewhere else.

But take a large sheet of plywood and drop it onto the surface, flat. It will make contact at every point of its surface at the same time - instantly. The water spider's physics would be shattered - he just observed an instantaneous action without any propagation! But that is possible only because the interference came from another dimension (from above the water.) One theory of BB suggests that BB could be a spark, a collision point between objects of higher dimensions.