Contact

by Carl Sagan

“What are you saying? They changed the geometry of space?” “Yes. We’re saying that space is topologically non-simply connected. It’s like—I know Abonnema doesn’t like this analogy—it’s like a flat two-dimensional surface, the smart surface, connected by some maze of tubing with some other flat two-dimensional surface, the dumb surface. The only way you can get from the smart surface to the dumb surface in a reasonable time is through the tubes. Now imagine that the people on the smart surface lower a tube with a nozzle on it. They will make a tunnel between the two surfaces, provided the dumb ones cooperate by making a little pucker on their surface, so the nozzle can attach itself.” “So the smart guys send a radio message and tell the dumb ones how to make a pucker. But if they’re truly two-dimensional beings, how could they make a pucker on their surface?” “By accumulating a great deal of mass in one place.” Vaygay said this tentatively. “But that’s not what we did.” “I know. I know. Somehow the benzels did it.” “You see,” Eda explained softly, “if the tunnels are black holes, there are real contradictions implied. There is an interior tunnel in the exact Kerr solution of the Einstein Field Equations, but it’s unstable. The slightest perturbation would seal it off and convert the tunnel into a physical singularity through which nothing can pass. I have tried to imagine a superior civilization that would control the internal structure of a collapsing star to keep the inte...