>>2
and
>>10
Correct. Relativity is the answer, here. Anything else is either wrong, baseless conjecture, or straight up bullshit. Gravity is merely the curvature of spacetime, OP.
I would highly recommend Brian Greene's books, particularly "The Fabric of the Cosmos". He does an excellent job at introducing people to the mind-bending theories of modern physics with a minimum of pain. I would even recommend his work over Hawking's.
Imagine spacetime as the net on a trampoline. When you stand on a trampoline, the net sags under your weight a bit. All objects with mass create pits like this in spacetime. Now imagine your friend standing next to the trampoline. He rolls a ball gently onto the trampoline. Eventually, that ball will hit you. If he angles it right, it might roll around a few times, but it will eventually fall into the pit you're making. If he rolls it hard enough, that ball could escape your pit and continue rolling off the trampoline, but its trajectory will likely be altered a bit.
Photons, like the ball, are not attracted to objects with mass. Not directly. Objects with mass alter the curvature of spacetime and the photons are simply following that curve. A photon continues to travel "straight", but the space it is traveling through becomes bent towards massive objects. "Gravity" is not a force per se, but refers to the fact that spacetime is curved by massive objects and the magnitude of that curvature.
It is so far unknown how exactly a massive object is able to affect spacetime. There are many so-called "theories", but the vast majority of them are pure conjecture (they make no predictions, are not falsifiable, no evidence to support them, usually merely clever mathematical frameworks, etc) and are thus not valid Scientific Theories.
As I point out often, our current understanding of the concepts of Space and Time are still laughably primitive. Some philosophers even question if our brains are even capable of fully understanding such things, let alone if it is physically possible to comprehend it. How do we expect to make meaningful progress in understanding the foundations of Time, if we can't even visualize something as simple as a few extra spatial dimensions?
>>5
What the fucking hell? You've either got incredibly shitty professors or you're a fucking dumbass. I would also recommend Brian Greene's books to you, as you seem to have somehow completely missed most of the fundamentals of modern physics. You, sir, boggle my fucking mind.