Fair enough, I was just throwing out there a bunch of possibilities I was thinking. I think the main "expanding earth" proponents have a better explanation than my understandings given here, I will have to go back and check on that.
I think part of the problem is, we don't really understand gravity enough to say if it is pushing OR pulling on us, or even a combination of the two, like a north pole and south pole magnetic force with a zero field at it's center(bloch wall). I think you are absolutely correct in thinking of gravity related to electromagnetism .A larger earth still gives more angular momentum for an electromagnetic "generator". There is also lots of interesting "electric universe" possibilities going on too. I am a long time student of Tom Bearden's work, and he says gravity is an electromagnet pulsing "scalar" wave, and Mass is an electromagnetic standing scalar wave .Think in terms of cymatics may be the best way to visualize the universe this way, check out starting at the 4min 16sec mark:
I don't think expanding earth people really talk about it being hollow though, I think it just made sense to me seeing it expand while familiar of hollow earth legends. It is all interesting dective story, and all the clues may be out there for us to find the truth...... Another thing I find interesting in all this too, is the ancient Gnostic story of the wisdom Goddess "Sophia" that turns into the earth :
https://www.metahistory.org/GAIA%20SOPHIA/FallenGoddess.php
I don't know about the Sophia thing, but the cymatics is interesting. I think I'm on the same page as you regarding how much we really understand about physics and gravity, though.
It always amazes me that otherwise brilliant people are blind to the fact that thousands of brilliant people have come before them thinking they had everything figured out only to be proven wrong later.