OP is apparently looking for 1D structures:
On one hand, a 3+1D Kerr black hole has a 1D ring singularity.
On the other hand, an event horizon has always codimension 2, so in 2+1D it is 1-dimensional.
OP is apparently looking for 1D structures:
On one hand, a 3+1D Kerr black hole has a 1D ring singularity.
On the other hand, an event horizon has always codimension 2, so in 2+1D it is 1-dimensional.