I assume you don't think the Earth is 2D mdinnerspace, since we can dig underground. So what shape is it? cuboid? cylindrical?
Also if the Earth is accelerating upwards, why do objects appear to accelerate downwards at a slower rate when further up??

The sciences, and their roots predate, and are fundamentally different from, philosophy. It could be said that philosophy is the child if that very early questioning which was not philosophical but practical.
"How?" rather than "Why?"