A wormhole in Time Square. Photoshop artist unknown.
Tech Level: 23
Tech Level: 23
Tech Level: 25
Wormholes are more properly called Einstein-Rosen Bridges, after the two men whose work in the early 20th century led to the first theories involving the extreme warping of space. However, the theory was considered too fantastic to be taken seriously at the time and was little more than an aberrant curiosity for decades. Then, in the 1980s, physicist Kip Thorne, trying to help his pal Carl Sagan create a believable means of interstellar travel for the novel Contact, looked hard at the old equations and, with the help of graduate students Michael Morris and Ulvi Yurtsever, found that wormholes perhaps weren’t that far-fetched after all. In the years since, the theoretical study of wormholes has been expanded considerably by a number of leading physicists.
The actual physics behind wormhole formation are incredibly complex; in order to save on space and the readers’ sanity, only extremely simplified versions are presented here. Links and references to more complete and technical works on the subject are provided at the end of this article.
In their simplest definition, wormholes are four-dimensional tunnels bored through the fabric of space-time itself. They can be created by warping space with very unlikely tools–either with singularities, which lie at the heart of those fear-inducing objects called black holes, or by tapping into the basic, planck-scale firmament of the universe itself.
A black hole is a spherical area in space that absorbs all light, energy, and matter that encounters it; a singularity is a pinpoint of super-collapsed matter, the remnant of a massive dead star, that lies at a black hole’s center. The singularity has infinite density and no physical dimensions–no length, no width, no height. It is quite literally an infinitesimally tiny point with the mass of an entire star packed into it. Its gravity field is so immense that its escape velocity exceeds lightspeed–hence its radius of utter darkness as seen from the outside. This gravity field also warps space to such a degree that physical laws as we know them break down.
But a sufficiently advanced species could also use this warping of space to their own benefit, to drill shortcuts through the fabric of the universe to reach across the cosmos.
Despite what has been depicted in a number of sci-fi sources, naturally-occurring black holes do not give birth to wormholes–at least, wormholes that a spaceship could survive passage through. These wormholes form only at the birth of certain rare singularities, go nowhere except to space-time dead ends, and last only microseconds. Any ship unlucky enough to be caught in one would be crushed instantly by the immense gravitational forces crashing in on them as the wormhole collapsed, if it could survive passage that close to a black hole to begin with.
Tech Level: 23
Black holes are not all alike; they come in a number of different varieties. It is only the artificial combination of very specific black hole characteristics that can give birth to a type of traversible wormhole called a Kerr-Newman Ringwarp.
A Kerr-Newman black hole must possess two important factors: a massive electrical charge and a high spin rate. These two factors affect the way the singularity warps space. By manipulating these as the original mass collapses allows the newly-born singularity to punch a hole through the fabric of space. At both ends of the new wormhole will be two black holes with the same singularity at their center.
Because the singularity has no physical dimensions, it does not actually “spin.” Rather, the angular momentum oblates the singularity–“flattens” it out–into a ring. The more spin it has, the larger the ring will be. Inside the ring is the tunnel that the singularity has bored through the fabric of space at its creation, pried open. It is possible to expand the ring so its diameter can exceed the black hole’s event horizon, the distance from the singularity at which its escape velocity exceeds light speed. At this point, the event horizon reconfigures itself around the singularity ring, allowing a ship to enter the Ringwarp through its center without being trapped by the black hole’s gravity. And thus a traversible wormhole is born.
Expanding the ring diameter is tricky at best once the ringwarp is formed, so the best means of ensuring a large wormhole opening is piling on the angular momentum as the black hole is formed. Spinning the target mass to near lightspeed as it collapses is the best way. Extremely advanced and powerful gravity manipulation would also help. The ringwarp mouth can also be held open or expanded with generous amounts of negative energy, as explained below.
Instead of creating a tunnel to another portion of our universe, a Kerr-Newman Ringwarp can be used to punch a hole into hyperspace. It is possible ringwarps could all open into the same hyperspace, allowing the creation of “hypergates.” The ship would enter one Kerr-Newman Ringwarp, travel through hyperspace, and exit through another Ringwarp in another star system. However, its also as likely that all ringwarps open into their own hyperspatial dead-ends, and can’t be used for FTL travel this way.
A civilization that had to depend on Kerr-Newman Ringwarps for FTL travel would have their work cut out for them. First of all, they would have to sacrifice already-existing masses–planets and stars–to create them. Vast expenditures of energy would be needed to create them (spinning the mass up to near lightspeed, then collapsing it artificially) and to maintain them. They would also be quite delicate–even a relatively small mass (say, that of an average automobile) hitting the star-heavy ring could upset its equilibrium and send the entire wormhole collapsing.
The alien Cheela in the novel Starquake used a Kerr-Newman Ringwarp to save several human astronauts