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Questions about Gravity

Brian Greene's elegant book about the Universe offers one of the clearest explanations I've ever read of Einstein's theories. During my latest reading of the book, I was frustrated by the image of the rubber membrane and the bowling ball as an analogy for how mass curves space-time. Everyone's seen it. I understand that it's difficult to convey the idea of a four-dimensional phenomenon in a two-dimensional representation, but I find this particular analogy to be a more a hindrance than a help when I'm thinking about the idea of mass causing space time to war. It's hard to shake the two-dimensional image in my mind's eye. I always think of one of those large bowls where a coin spirals down toward the hole in the bottom. Instead, I try to cultivate in my mind the understanding that gravity pulls one toward the center of a massive object and it exerts the pull in every direction. I still can't grasp the bit about the warping of time.

Enough ranting. The main point of this whole thing was to write down the questions that are perplexing me. I always find myself pondering about the nature of the thing that is being curved. When a body is in free fall, what is it that guides its trajectory toward the center of the spherical object it's approaching? Is it the mutual pull of the gajillion particles (or waves!) of matter each emanating its own little 'gravity waves', or is it the mere presence of a large aggregation of mass curving something we cannot detect, but which has the ability to affect our motion? What if the massive object is not a sphere, but, say, a huge cylinder or a trillion megaton, 500,000-mile long wavy banana? Does it bend space time in such a way that the gravitational silhouette follows the irregular contours of the body? If a smaller body were in free-fall in the pull of the non-spherical mass, toward which point in the body would the "fabric" of space time direct its path? So many questions! Such a vast, unexplored wasteland of ignorance in my head!
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