Shooting Wormholes to the Stars

I chaired the “Exotic Science” session at the DARPA/NASA sponsored 100 Year Starship Symposium, held in Orlando, Florida, September 30 to October 2, 2011. There, the propulsion experts pulled out all the stops in attempting the design of a starship that might reach the stars in a human lifetime, and they essentially failed, even when invoking nuclear or antimatter energy sources. The stars are very far away. Reaching them is a very difficult problem with no easy solutions . . . except, perhaps, for one partially baked idea that was introduced in my column in the May 1990 Analog. Looking back at my old column, I realize that it had a few mistakes and could have been presented better. So, in the new DARPA context, let’s revisit the idea here.  First, let us assume, following the lead of Thorne, Morris, and Yurtserver, that we can snatch microscopic wormholes from the quantum foam and stabilize them. If we keep a wormhole mouth microscopic in mass and size, it behaves much like a fundamental particle with a very large mass, perhaps somewhat in excess of the Planck mass of 21.8 micrograms. For the purposes of calculation, let us assume that we can produce a stabilized microscopic wormhole with a mass of 10 Planck masses or 218 micrograms. Could such an object exist? Visser has described wormhole solutions to Einstein’s equations of general relativity that are flat-space wormholes stitched together across a cut and co-stabilized by a tiny loop of negative-tension cosmic string. A wormhole like this might occur naturally in the aftermath of the Big Bang and might have the size and mass described above.