How Big is the Unobservable Universe?

I’ve been processing this for a while and it seems like there is an inconsistency. Are you sure that the Y axis of your graph is supposed to be V/V? For your graph to be consistent with Ethan Siegel’s article, it should be R/R.

Which one is correct and which one is incorrect?

I don’t know which dataset Ethan Siegel is using (the one I did is using Planck 2018), or even what calculations is he using to obtain these limits. There are other limits that can be made, e.g., by looking at opposite directions in the sky and observing that the Universe does not “repeat”. Note that we both agree that V/Vobs of ~10^7 is within experimental bounds.

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