The doctrine that at least certain ideas (e.g., those of God, infinity, substance) must be innate, because no satisfactory empirical origin of them could be conceived, flourished in the 17th century and found in RenÃ© Descartes its most prominent exponent.
Local Curvature of Space. According to Einsteinâs theory of general relativity, massive objects warp the spacetime around them, and the effect a warp has on objects is what we call gravity. So, locally, spacetime is curved around every object with mass. Overall Curvature of Space
Because the universe is expanding, the question of the distance to a very distant galaxy is hard to answer. It all depends on your point of view. This is the problem of defining a distance in an expanding universe: Two galaxies are near to each other when the universe is only 1 billion years old. The first galaxy emits a pulse of light. The second galaxy does not receive the pulse until the universe is 14 billion years old.