WallyM7, the expert I’m feeding off of is Jim al-Khalili, a theoretical physicist at the University of Surrey. The book is “Black Holes, Wormholes & Time Machines” Institute of Physics Publishing, 1999. It’s a good read for any layman interested in this way-out cosmology and its chronological possibilities.
al-Khalili didn’t actually put forth these ideas. Mostly he’s drawing off Kip Thorne of Caltech. Cecil mentioned the paper in his column.
Basically, Thorne and his collaborators started out with a group of properties for a traversable wormhole. It needed to be large enough for people to pass through, it needed to be stable and constantly open, it couldn’t have event horizons, singularities, or fierce tides, and it needed to be abitrarily short through the wormhole for an abitrarily long distance through normal space.
They found that the existance of such a wormhole was consistant with the present theories of spacetime, though the creation of it may not be. So they just ignored the problem of making it, and studied its theoretical properties.
Now there are a number of physicists that study these possible but improbable items. Basically, it is a rarified exercise in the mathematics of general relativity.
Matt Visser of Washington University has even written a textbook on the subject.
By the way, one of the hardest parts of the wormhole to theorize was the stability and keeping it open. It requires matter of negative mass. One thought is that this exotic matter might exist in cosmic strings, though they are a theoretical fantasy themselves.
Nevertheless, these people are surely more expert than you or I.
“If you prick me, do I not…leak?” --Lt. Commander Data