Bob Knodel's presentation on the science of Flat Earth from Flatoberfest 2021
TL:DW
-The atmosphere and space: The differential between the commonly accepted values for the vacuum of space and the atmospheric pressure of Earth would create a force magnitudes greater than the weak force of "gravity". Ergo the atmosphere could not exist if it were next to a vacuum as the atmospheric gases would escape to fill the void.
-Theories for the downward force: Incoherent magnetism, that is a magnet which only attracts as it does not have a coherent field (no North/South dipole)
-Explaining the electrostatic potential found all over the Earth: Every 10m increase in altitude increases voltage potential by approximately 100V. This could not occur if the Earth were a globe, as potential in a radial electric field decreases in a non-linear manner. Only between two flat surfaces is the field uniform and the gradient of electric potential linear.
-Other neat phenomenon that support Flat Earth and a firmament