What deformations are possible with spacetime?
By 'deformation' I am referring to the kind of change in spacetime caused by the presence of a mass which deforms spacetime sufficiently to deflect photons of light, or in the extreme case of a black hole, 'compress' spacetime into a singularity, or in the case of a rotating binary star system to creates waves comprised of compressed spacetime.
By 'possible', I mean 'theoretically' possible.
Is it a case of what you can do with a room full of jelly, you can also do with spacetime? If this analogy is not good then why is that?
Is it possible to make a hole in spacetime as it is with jelly, in that case creating a volume of vacuum within the jelly?
Pictures of worm holes imply that a volume of spacetime can have a surface. Is it actually possible to create a surface that bounds spacetime?
Must every point in spacetime remain attached to its current neighbours?
In the case of jelly, one could isolate a sphere of jelly and then rotate it relative to the rest of the jelly without creating any kind of gap. Is that possible with space time?
One paper talks about cracks in space-time (following a change of state after the big bang). Is that possible?