I saw the headline, before I even scrolled down I started pondering the infinite vastness of space. While contemplating this unending expansion I thought to myself, does space really go on forever, or does space curve somehow, such that if you travel far enough in what you perceive as one direction you would actually end up where you started?

Then I scroll down and yours is the first comment I read! Lol!

Now: serious question; is this really a scientific theory to explain the limits of space, or just a philosophical concept that you’ve developed?

earth. If you want to learn a lot more about space, relativity, how big the universe is in plain understandable language watch the award winning show “Everything and Nothing”. I have watched it several times and it helps you understand what is “nothing”, describes the universe in plain understandable terms and ends with a picture of what the known Universe probably looks like. The speaker ends by saying that the depiction of the universe that is shown at the end probably represents the greatest achievement over the past 500 years. Simply remarkable show. I saw it on Amazon Prime but unfortunately it’s not free at the moment. Maybe searching around the internet you can find a free version.

https://www.amazon.com/Everything-Nothing-Amazing-Science-Empty/dp/B01MY6PO1C

Note that the observable universe is not the same as the universe. We seem to be limited by the speed of light to some unknown fraction of the whole thing. I don't think there is agreement on estimates on the actual size of the universe, but from Wikipedia it could be very tiny compared to the whole thing:

ideas that form the foundation or our current understanding of space and the universe.

from each other. Wild.

Excellent! Btw that's the behind-the-scenes version, here is their finished work:

'Space is big. You just won’t believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it’s a long way down the road to the chemist’s, but that’s just peanuts to space.'

'"Have some sense of proportion!" she would say, sometimes as often as thirty-eight times in a single day.

And so he built the Total Perspective Vortex - just to show her.

And into one end he plugged the whole of reality as extrapolated from a piece of fairy cake, and into the other end he plugged his wife: so that when he turned it on she saw in one instant the whole infinity of creation and herself in relation to it.

To Trin Tragula's horror, the shock completely annihilated her brain; but to his satisfaction he realized that he had proved conclusively that if life is going to exist in a Universe of this size, then the one thing it cannot afford to have is a sense of proportion.'

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