Do we all agree that if all light does bend upwards (not just "celestial light") ...
I've been holding off on posting in this topic, because I wanted to give it some thought. As I believe we discussed on .net, I tend to think celestial light is refracted through some medium (just for self-amusement, I've called it a 'firmament'). I'm virtually certain that terrestrial light does not, and tend to agree with James that "Bendy light" is pseudo-science. I'm intrigued by this celestial sphere you've developed, to be perfectly honest, because if tends to agree with my own admitted bias. Would it not be possible under this model that only celestial light is so refracted and that terrestrial light is not?
Also, I will agree that if all light does bend upwards, then the earth would appear to curve or bend away from one.
It is possible that only celestial light is bent. Consider this mechanism. Suppose photons can carry some sort of equivalent of charge, which couples them to an as yet undiscovered fundamental force that causes their trajectory to bend. Furthermore suppose that the heavens are ubiquitous in this sort of charge, and give any photon emanating from them a piece of this "charge". However, suppose that upon interaction with terrestrial molecules, the photons decay, and lose their "charge" to another weakly interacting particle. Therefore, the photons' path would no longer bend, and neither would any photons created on Earth. Of course this is massive speculation, but it shows the celestial/terrestrial split is workable. The negative aspect of this terrestrial/celestial idea is that it requires new laws of physics.
I admit bendy light is far in the realm of speculation. It seems pseudoscientific since there is such limited evidence we can use to investigate it. However, all FE'ers need to realize that bendy light must exist. As shown by simple geometric calculations, Rowbotham's perspective model is completely inadequate to explain sunsets. The traditional model also is severely limited in its ability to predict the length of days and the nature of celestial motions in the southern annulus.