I once read something to the effect that the apparent diameter of the sun's disk is just about the same as the light curvature due atmospheric refraction (or is it gravity-bending? that sounds unlikely) when it reaches you at a tangent; with the net effect being that when the sun's disk just touches the horizon it's "really" entirely below it. And it's by this means we know that, like the light in your refrigerator when you close the door, the sun doesn't go out when it falls below the world's edge and everything you've been told otherwise is a damned lie.
[Dan] Take it up with CdM or Breadmaster. But before you do, consider: wouldn't your "width" theory mean that you'd be forever smashing the fridge light bulb in the door? Something about that doesn't ring true.
Can't help I'm afraid but do have a very Happy Christmas wherever you are. _, who is now 3, is already as manic as can be. Not sure how to burn off his energy...
(Dan) True. If you see the sun on the horizon it is geometrically just below it. It adds a few minutes to daylight at each end. It's refraction (strictly, differential refraction) not gravity-bending which would need a mind-bogglingly dense earth. On Venus the refraction is so large the horizon is above horizontal and it looks as if you're living in a bowl. A hot one, 460°C. No oxygen. Occasional showers of sulphuric acid. (rab) See MCIOS, FUQs.