space-time curvature
The attraction of one mass to another or the bending of space-time.
Very loosely, relativity says massive objects change the geometry of space/time. Bending both time and space.
Scientists call it refraction.
I call it 'diffraction'.
I call it the process of 'diffraction'.
bending space
Water will bend a beam of light. Try this put a stright pincil in a glass of water. The pencil is still stright but looks bent. The water is bending the beam of light.
Refraction
Time doesn't affect space. Space and time are the same thing in relativity; that's why we call it spacetime. Mass affects spacetime and spacetime affects mass.
Space. In fact, astronomers consider time and space to be inextricable from one another. They call it "timespace".
Yes outer space exists We haven't been in space enough to have the answers but there are widely excepted theories. According to Einstein's theory outer space isn't as much held together as it is supposedly sitting on a plane of Space-time. Gravity is a force imposed by matter stretching and bending the space time. Space is expanding so that suggests it is not "held together".
refraction