Part of the genius of Traveller is that it leaves a lot of room for the referee to explain why things work. It also helps personalize your Traveller Universe.
Coming up with explanations for the various piece of Traveller Tech is a favorite pasttime for many Traveller Referees including myself.
One thing I messed around with is how Jump Drive works. It doesn't have much in the way of rules but what I like about this explanation is that it boils all of Traveller's super tech down to one difference in what we know about the universe. The ability to control gravity.
Many people don't realize this but a lot of the far out stuff like Time Travel, FTL Drives, are possible in our universe. However they require extreme manipulation of time-space i.e. gravity and tremendous amounts of energy. A daunting engineering task by any standards. However if somehow you found a efficient way of controlling and manipulating gravity then a lot of these things become possible aside from nifty grav belts and speedy air/rafts.
It turns out that there is one theory out there that can serve as a explanation of Jump Drive and explain why the control of gravity is important to it's discovery. Let's take a jaunt to the last 21st century and see how it happened.
Kaukji Hyperspace Shunt Drive aka the Jump Drive
(Excerpted from Omnipedia on June 7th 2148)
Kaukji Hyperspace Shunt or KHS Drive is an outgrowth of continuing research into control of gravity. When manipulation and control of gravity became possible in 2071, researchers realized that several avenues of achieving Faster Than Light (FTL) speeds became possible. In the late twentieth first century several FTL theories emerged that remain consistent with Einstein's Theory of Relativity. All of them had massive engineering problems to overcome or required the generation and control of massive gravity fields. See
With the discovery of how to generate and control gravity fields several groups launched research programs to investigate intense gravity fields. By 2085 many of these research groups relocated to stations built in the asteroid belt as gravity field strengths were too dangerous for planetary surface or near orbit.
A group, sponsored by Japan's Institute of Technology, was involved in the investigation of warping time-space. This group was lead by Dr Fawzi Kaukji. On March 16th 2087, Experiment Sled #13 was enabled. A malfunction caused a field to be generated to be a 100 times stronger than planned. Space was folded around the Sled and it disappeared from the sensors of the Kaukji's group. 170 hours later it reappeared 1 AU near The California University Research Consortium Station where its telemetry signals were picked up. Its travel path (if it could be called that) cut a chord across the orbit of the asteroid belt. It traveled over 3 au from JIT station to .25 au off of the CURC station.
While it didn't travel faster than light, analysis revealed it was 8 times faster than best drive at the time. The research program of Kaukji's group was altered and the next six sleds were devoted to the exploration of this effect. Experiment Sleds #15, #16, #18,and #19 all disappeared without a trace. #17 reappeared 160 hours later in the same location with its structure shattered.
Note: Sled #18 was found in 2142 in Jupiter's trailing trojan point by a GsBAG mining ship.
Experiment Sled #20 activated on July 16th and reappeared 180 hours later. It was found 1 au near the Earth/Moon system. CURC began a parallel research effort beginning in May and recovered its first experiment sled on July 28th.
By the fall of 2087 several additional research consortium's were able to replicate both the CURC and JIT results. However the CURC efforts stalled when they moved their main research operation to Earth Orbit. For six months they experienced no successful recovery of experiment sleds. Meanwhile Kaukji published two important findings. The first that successful recovery always occurred between 150 to 185 hours, and second by varying the initial field configuration; direction and distance can be controlled.
In November of 2088 JIT awarded Nissan Space Inc. the contract to build a craft capable of carrying a man. In April 2089 the Sunrise, folded at the Nissan Station in the asteroid belt and reappeared 172 hours later 200 diameters outside of earth orbit. In August 2090, Kaukji announced that KHS field decay was constant +/- 15 hours regardless of distance traveled. In addition a successful fold could not reliably occur within 100 diameters of a massive object. This opened the possibility of Faster Than Light Travel.
This is based on the Alcubierre drive specifically a variant where space is folded so that only a narrow neck connects the bubble with the real universe. This reduces the energy needed to "charge" the warp field by several order of magnitude. This neck is microns in diameters.
The big problem with the Alcubierre drive is controlling speed and direction. What science discovered that there are 15 possible configurations of Alcubierre fields that are stable enough to initiate travel. If you setup one of these 15 fields properly you will go in a particular direction faster than light. The fields will naturally collapse 150 to 180 hours later causing the ship to emerge into normal space. This also explains why in some versions of Traveller you have the issue of Jump Shadowing. If the straight line path comes within a 100 diameters of a massive body your fields will destabilize and pop you back out.
However only the six fields are dynamically stable corresponding to Jump 1 to 6. Think of the fields as being at the bottom of a valley. If you get the parameters slightly wrong you naturally slide to the bottom into the most stable configuration.
However 7 to 15 are like being on a top of a hill. Even the slightest deviation from the ideal parameters will cause your fields to destabilized. Which why canon Traveller stops at Jump 6.