i have read some about it... there is a sun in the center of the world that allows life for unknown intraterrestrial habitants ? Almirant Byrd expedition was something real or that is just something false..
check HP Jake Carlson's website. There is a little about it in there. I don't remember which sermon, though. Maybe resurrecting the fallen angels or something like that.
the earth is not hollow,its like a honey comb with so many civilizations living in it both good and bad,like the reptilians for greys for example,and there is no sun beneath the earth but an artificial light source which provides light similar to the sun for the beings living in it.it is not possible for an actual sun to be under our earth.