Note also that wormholes should look spherical, not like tunnels!
Finally we get a fairly lengthy section on using wormholes for time travel.
Now, you might think, remembering your school physics, that this completely rules out the possibility of constructing traversable wormholes.
But, as Morris and Thorne stress, it is not impossible and " we correspondingly cannot now rule out traversable wormholes.
such wormholes have been seriously suggested, as being within the capabilities of a future civilization.