Earth Expansion is the notion that the Earth's tectonic plates aren't subducting, but rather pushing against each other as Earth gets bigger<<
Which is exactly backwards, since if the Earth were expanding, the plates would all be pulling apart. Not only is the idea total nonsense, it is also internally inconsistent.
It is impressive how committed these people are, though. I once had one of them tell me that the Pacific and Nazca plates were not subducting. He said this as we were standing on the Ring Of Fire.
(remember - the Ring Of Fire is made up of 75% of the volcanoes and 80% of largest earthquakes in the world and they are all powered by subduction. He was willfully ignoring the Andes, Mexico/California, Cascadia, Alaska, Kamchatka, Japan, the Philippines, eastern Indonesia, Tonga, New Zealand, and Antarctica. So Yeah.)