Most likely you're losing karma because you come across as trolling. In case you're not, picture "down" as towards the center of mass. On the surface of a spher

Most likely you're losing karma because you come across as trolling. In case you're not, picture "down" as towards the center of mass. On the surface of a sphere, that means perpendicular to the surface. At the edge of two faces of a cube, "down" is through the edge (between the faces), with the faces 45 degrees off-vertical. Like on a mountaintop.