User blog:Mr.Robbo/Darned FTL!

Unabridged Version
In science fiction I've always tried to put a lot of thought into faster-than-light travel. The problem is that I prefer hard science fiction, but some form of superluminal travel (or at least communication) is a must for large interstellar civilisations; in scientific discussion just about all forms of useful faster-than-light travel (even the most plausible, wormholes) are controversial.

The Zambarau Concord was small enough that I could do away with superluminal travel and just have them use relativistic starships, but my new civilisation, the FCZ, is a lot larger, making superluminal travel (or at least communication) necessary for any kind of cohesion.

Currently there are three ideas running through my head;

Microscopic Wormholes (most plausible)
Microscopic wormholes would be fairly easy to make for an advanced civilisation, and aren't plagued as much by the stability problems of larger wormholes. A small amount of negative mass/energy material would be required to hold the wormhole open, which would be the main technological requirement.

The destination mouth of the wormhole would have to be transported to the destination by a slower than light starship, meaning the expansion of such a civilisation itself would be limited by the speed of light.

You can't fly a spacecraft through a microscopic wormhole, but a civilisation could still transmit a huge amount of data per second through such a wormhole. As for physical objects, nanorobots could probably be passed through. An advanced civilisation would probably be able to support itself around microscopic wormholes by, instead of sending physical objects through, transmitting the instructions for building the object on the other side.

People may also be able to 'upload' themselves into computers for transmission through the wormhole. This might not be as far-fetched as you might think, and is definitely more technically feasible than the following options.

Large-Scale Wormholes (less plausible)
A large scale wormhole is usually thought of as being many metres in diameter, making it possible to pass a person or spacecraft through it. A civilisation would construct a large-scale wormhole by 'inflating' a microscopic wormhole; this would require much more negative mass/energy than a microscopic wormhole, so some sort of mass production technique would have to be devised.

Like with microscopic wormholes, the expansion of a civilisation using large-scale wormholes would be limited by the speed of light, though people could use the wormholes to travel at faster-than-light speeds within the civilisation.

Large-scale wormholes would weigh billions, even trillions, of tonnes, and would have to be placed at a safe distance from stars and planets to prevent the gravity of the wormhole from causing problems. When a wormhole destabilises it is thought that it would turn into a black hole and release part of its mass as energy; with microscopic wormholes that's a small explosion; with large-scale wormholes we're talking about cracking planets and sterilising whole solar systems of life. Not only would this be unsafe for the inhabitants of a solar system, but wormholes could be weaponised, resulting in a civilisation that is seriously OverPowered.

Alcubierre Warp Drive (least plausible)
Then there is the classic, slightly tired concept of the warp drive (groans, reads Stephen Baxter's Ark, mood picks up). The Alcubierre metric involves changing the structure of space-time to allow for faster-than-light travel. This, also, requires quite a lot of negative mass/energy. Some say that this is more difficult than wormholes because of the precise space-time geometry required, while others say that because you are just stretching, rather than breaking (as in wormholes) space-time warp drives are easier than wormholes.

With a warp drive an advanced civilisation could expand faster-than-light, but only if it could overcome the problem of not being able to communicate through the warp bubble, which would mean the warp drive can only be controlled from the outside and can therefore only travel certain set routes.

Critics of the idea of warp drive have found a variety of problems, such as the fact that; Proponents of warp drive are coming up with solutions at an equal rate (listed respectively); For more information on warp drives, please read this brochure...
 * 1) Warp drive requires negative energy.
 * 2) Warp drive requires enormous amounts of energy.
 * 3) The warp bubble wall must be extremely thin (on the order of planck length).
 * 4) You cannot communicate through the warp bubble to make it start, stop, change speed or change direction.
 * 5) The wall of the warp bubble is like the horizon of a black hole, and blasts everyone inside with massive amounts of radiation.
 * 6) The warp drive collects up matter from interstellar space. Therefore, while everybody in the destination solar system are laughing at the people in the warp-ship (who've been blasted by radiation), the warp drive stops and releases all of this interstellar matter as energy in the form of a giant death-ray.
 * 1) Richard Obousy - manipulating extra dimensions to warp sape-time with a particle accelerator.
 * 2) Chris Van Den Broeck - a space-time configuration that makes the warp drive microscopic on the outside but huge on the inside (like a TARDIS!).
 * 3) Richard Obousy with his extra dimensions again.
 * 4) Someone (I forgot their name) designed this wierd metric with one warp drive embedded in another to solve this problem.
 * 5) Chris Van Den Broeck with his TARDIS again.
 * Yep, Van Den Broeck's TARDIS can solve this problem, too!

Hyperbolic Geometrodynamic Warp Drives and Beyond (pdf)

Hyperbolic Geometrodynamic Warp Drives and Beyond (html)

But remember, there's only more written about warp drives because they're more controversial, not because they are studied more in physics (wormholes have far more papers written on them than warp drives).

Abridged Version
Please help me decide what method of faster-than-light travel I should use for the Free Co-operative Zone.