Note: This entry is a rough draft.
The Super-light-velocity Spatial Displacement Drive (SlvSD Drive), or the Fold Drive as it is commonly called, is a Tirolian Faster Than Light (FTL) propulsion system first developed around the year 1000 AD. The Tirolians were the first race in their local group to develop FTL travel.
In the year 872 AD, Rilac physicists on Tirol had just come to terms with super dimension spatial theory. This same theory was postulated over a thousand years later on Earth as the ADD model, also called the model with large extra dimensions. Super Dimension Space was a model framework that attempted to explain the weakness of gravity relative to the other forces. This theory stated that all fields are confined to four-dimensional space, with the exception of gravity, which propagates in several additional spatial dimensions.
In the year 901 AD, this theory was proven when physicist managed to cause sub-atomic particles in four-dimensional space to “swap places” with their equivalents super dimension space while excited in a monopole magnetic field environment. This led to the hypothetical proposition of swapping large amounts of matter into super dimension space in order to travel faster than light. This was merely a theory, since it was not known at the time if matter and energy behaved any differently in super dimension space.
In 994 AD, the first working SlvSD Drive was “successfully” tested. Successful in this case being a highly subjective term, since the test probe was never heard from again. However, it did show that large amounts of matter could successful be swapped for super dimension space mater. By 1002, a successful “Space Fold” was finally conducted when a test probe was swapped for super dimension space, and then an hour later swapped back into four dimensional space. This probe brought back with it a wealth of information concerning the nature of super dimension space, allowing physicists on Tirol to create a cosmological model for super dimension space.
Super dimension space is, in layman’s terms, just one of several extra, large dimensions. The overall topography of super dimension space mirrors four dimension space, but there are no corresponding bodies of mass in equivalent to those seen in the same “location” in four dimension space. All mater in super dimension space is subatomic. However, large masses in four dimension space, “cast a shadow” in super dimension space in the form of gravitational fields. Because of this, navigation in super dimension space must take into account the location of bodies of significant mass in four dimension space.
In super dimension space, mater and energy move at a uniform speed. When an object folds in to super dimension space, it immediately is traveling at this speed (known as the Super Dimensional Constant). Direction of travel is determined the object’s direction of travel in four dimension space at the time of fold in. Speed at time of fold in has no effect on speed in super dimension space since everything moves at the Super Dimensional Constant. Distance traveled is determined by the amount of subjective time spent in super dimension space before fold out.
The Super Dimensional Constant is 64,714,024,413,139.5 meters per second, as observed from four dimension space. In relativistic terms, this is 215,862.75 times the speed of light (these numbers have been rounded to manageable decimal places). To put this into perspective, a direct fold from Earth to Tirol (a distance of 1812 parsecs) would only take about 10 Earth days. A direct fold from one side of the Milky Way Galaxy to the opposite side (a distance of up to 37 kiloparsecs) would take only 200 or so days. However, single folds over such great distances are not possible.
Limitations and hazards of SlvSD Drive travel:
Firstly, given a perfect navigation solution, a direct fold on a modern Tirolian vessel, such as the Zentraedi Nupetiet Vergnitzs-class Fleet Command Ship, is only guaranteed to be accurate out to a distance of 10 kiloparsecs. And this is given a “perfect” navigational solution. Even the slightest variation in direction of travel at time of fold in can create massive deviations in path of travel in super dimension space. So, for example, if a ship is conducting a fold and a small piece of space debris nudges the ship slightly by +/- .000001 degree right before the moment of fold in, the ship could find it’s self massively off course 32,600 light years down the line when it de-folds. Worse still, its new deviated course could take it right through the gravity well shadow of a planet or sun, destroying the ship before it even gets to its point of fold out.
Additional variables are introduced by the proximity of other masses of mater. A planet, or even an object as small as another ship, bend space time. In some circumstances, it is not possible to estimate the exact amount of distortion created by a body of mass. When folding inside the curve of this mass, if the amount of deflection is not correctly calculated the folding vessel may once again depart on an incorrect trajectory.
Because of this danger, most prudent ship’s captains rarely make a single fold of anything more than 500 parsecs. An aggressive captain may conduct a single fold of two kiloparsecs. Only a mad-man would risk a fold of over three kiloparsecs. Additionally, most folds from inside a system only take a ship to the immediate vicinity outside the system, where a second fold is usually conducted outside the influences of gravity wells and intersystem space debris.
When traveling in super dimension space, mater experiences gravitational time dilation due to the increased gravitational forces in this dimension. The net result is an average time dilation of 0.004 percent. That is to say, for every subjective second spent traveling in super dimension space, 249.9612 objective seconds pass in four dimension space. The term “average time dilation” is used because if a mass passes within the shadow of the gravity well of a large mass in four dimension space, the increased gravitational force will dilate time further. Since the point of fold out is determined by measured subjective time while traveling, this can cause a ship to reappear in four dimension space well off course.
Additional obstacles exist in super dimension space known as fold faults. A fold fault is an area of increased sub-atomic mater density within super dimension space. When attempting to de-fold in a fold fault, the higher sub-atomic density can cause a geometric-progression of energy consumption: that is to say it will suddenly take a much higher amount of energy to fold out of super dimension space. If the energy requirement is greater than the energy potential of the ship’s main power source, the ship will have to continue to travel in super dimension space until it is out of the fold fault. This is known as a fold dislocation. In some extreme cases, it is speculated that the rise in required energy consumption can become so severe when passing through a fold fault, that a ship may no longer be able to maintain it monopole magnetic field. When a ship experiences a collapse of its monopole magnetic field while in super dimension space, the ship’s mass in instantly converted into its constituent sub-atomic particles.
For this reason, it is considered best practice to proof all point to point routes through super dimension space with a probe drone before committing to a fold. Of course, this is not always possible. Especially in the later years of the Tirolian Mercantile Empire, it was considered a waste of precious protoculture to proof new routes, so ships either stuck to well established fold points or took their chances when the tactical situation demanded it. The United Earth Expeditionary Force never took this precaution, being unaware of the prevalence of fold faults. It is speculated that the UES Pioneer fell victim to one such fold fault, and is presumed destroyed.
Way at the bottom of the list of hazards is fold sickness. Approximately one out of fifty individuals are susceptible to this condition, which has symptoms described as similar to that of motion sickness.
The SDF-1 Macross incident:
When the crew of the SDF-1 attempted the first Space Fold by a humans, the ship’s Captain intended to the ship to fold out on the other side of the Earth’s moon. Though a tactically sound decision, it was made out of a lack of understanding of the inherent limitations of travel through super dimension space. The first mistake was attempting to fold while the ship was traveling (falling) towards the earth. Though this was the correct direction, it would have sent the SDF-1 straight through the center of the Earth’s gravity well in super dimension space, crushing the ship like a grape.
Lucky for the crew, the curvature of spacetime caused by the Earth itself meant the SDF-1 was falling at a curing trajectory relative to super dimension space. This gravity well deflection effected the actual direction of travel once the ship folded in, allowing the ship to miss the center of the Earth’s gravity well in super dimension space.
The second mistake was the lack of knowledge concerning the huge amount of gravitational time dilation while traveling in super dimension space. The original intent was for the SDF-1 to de-fold well outside of the Earth’s Moon’s orbit at a distance of 18 million km (or approximately 18.5 million km from their position on the opposite side of Earth). With the Super Dimensional Constant being known, this gave them a time to de-fold solution that was 250 times to long. This, in turn, meant they traveled 250 times further than they intended to, placing them just outside the orbit of Pluto at its Perihelion.
It is still unknown to this day why the SDF-1’s fold generators did not de-fold along with the rest of the ship.