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The geometry near space-like infinity: The “point” i0 has been blown up to a cylinder which is attached to ℐ- and ℐ+. The physical space-time is the exterior part of this “stovepipe”. The “spheres” ℐ± and ℐ0 are shown in blue and light green, respectively. The brown struts symbolize the conformal geodesics used to set up the construction. Note that they intersect ℐ and continue into the unphysical part.
