Gravitational lensing? Whoa, that sounds interesting - or is it something that will make me have a moment of 'science madness' again? I love learning about physics; the concepts make me feel like a very small thing in the universe, humbled. And some of the theories can be almost like theology - if you get my meaning!
The Two Trees are obviously divine in some way within Arda and must produce not only light but Light (and I do wonder if the two are not the same thing?) - to look into a Palantir and actually see the Two Trees would be an incredible thing, and Gandlaf clearly believes that with enough effort to wrest control from Sauron it would be possible. One Palantir was kept by the Elves on the shores of Middle-earth - was this to look to Valinor?