That is an excellent question. No one knows the answer. Scientists can prove that space in fact bends and that mass is the cause, but they don't know why.
---------------- The big bang is the expansion of the universe and is still visibly in progress. Scientists don't know why it is expanding. The expansion can be proven many ways but the reason for it is unknown.
In science it is okay to say, "I don't know." .
This is how Dr Einstein approached the issue: What he called his "happiest thought" was the equivalence of gravity and acceleration. Picture yourself standing on the floor of a spacecraft that is pointed vertically upward. The spacecraft has no windows and no instruments.
In case 1, the spacecraft is sitting still on the surface of the Earth (a 1G gravitational environment). In case 2, the rocket is accelerating in empty space at 1G, far from any stars or planets. Now, what is the difference between these two cases?
Einstein's happiest thought was: - there is no difference between these two cases. They are precisely equivalent (Einstein used elevators, not spacecraft, but the net result is the same). Now picture yourself in that same spacecraft.
In case 3, you are floating free in empty space. In case 4, you are falling through the atmosphere toward Earth, but you have not yet hit the ground. What is the difference between these two cases?
Again, Einstein said there is no difference. Imposed acceleration is equivalent to the effects of a gravitational field. The 1G force that you feel acting upward on the soles of your feet as you stand on the Earth is the same thing as a rocket pushing you upward at 1G acceleration.
In the same sense, when you pass by a planet in a trajectory that is curved by that planet's gravitational field, you are not "pushed" against the outside of the cabin as you swing past. You remain in free fall during the entire encounter. In fact, with no windows and no instruments, there is no way for you to know that the planet is even there.
Your spacecraft is following a curved trajectory through distorted spacetime - the straightest path available to it - with no forces acting on it at all. Another way to look at this is with a flashlight shining through the window of a spacecraft. If the spacecraft remains motionless within the reference frame of the flashlight, then the photons will strike the opposite wall of the cabin at the same height as the window.
However, if the spacecraft accelerates upward after the first few photons have entered the window, the spacecraft will "leave these photons behind" as they travel across the cabin, and the photons will strike the opposite wall at some location slightly below the height of the window. To the pilot of the spacecraft, these photons will appear to follow a curved path in space and time as he sees them cross his cabin. In fact, within his frame of reference, they will follow a curved path.
What Einstein said was that the same effect would be produced if the spacecraft were merely sitting on the ground in a sufficiently strong gravitational field - because this strong gravity is equivalent to an upward acceleration. He was so confident of this that he applied the resulting math to make a prediction of the bending of starlight by the Sun of the apparent position of stars close to the Sun's disk during the solar eclipse of 1919. His predictions were completely accurate, and these results made him famous.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.