How exactly does FTL work in the Frencoverse?
Just curious for the thoughts of everyone else, and wondering if like, all the various factions use the same method to achieve FTL speeds.
Humanity got it's hands on FTL from reverse-engineering the wrecks of Utan ships after the invasion, so everyone's FTL is running on the same base function (that doesn't count tweaks, though).
As for the technical side of things, Auro had a great explanation as to how it functions that I went with.
I'll copy and paste the TG I sent this in.
"In essence, it's a warp drive. But as the speed that the ship travels at increases linearly, the energy requirement to do so increases exponentially. Now, as time passes and more efficient drives are developed, this speed-energy curve gets shallower and shallower. There's also a 'minimum initiation energy' necessary for the drive to actually work, probably roughly equal to the energy required to travel at 1c. As time passes, this energy also gets dramatically lower.
Furthermore, the shape of the warp bubble also matters. Naturally, a large warp bubble needs more energy than a smaller one. But also, the most efficient shape is a perfect sphere. The bubble can only be a spheroid, but the larger the ratio of the spheroid's longest axis to the shortest axis, the less efficient it is. This logically leads to spheroid ships, which are ugly, so I reckon we can make this inefficiency not very large so one can simply disregard it as long as one's ship isn't the shape of a bloody pencil.
It can only be activated when one's not too deep in a gravity well, but this isn't an enormous limitation - for planets the size of Earth and slightly larger, that only means low orbit. There's only a notable difference for enormous bodies, such as stars and black holes.
To prevent the situation of "my FTL bombers warp right to your planet, unleash planet-killers, warp back immideately", essentially stealth in space, a craft can be detected when it's using the warp drive. A craft in FTL flight can also 'see out' of the warp bubble just fine, which is kind of necessary if you want to be able to know when to stop warping anyway. But all it can do is see out and send/receive communications - it can't fire weapons while warping or anything like that.
There is no effective way to engage/destroy/damage something in FTL flight; however, a technology exists which can 'deflect' a craft which is flying past, causing its trajectory to curve away. A beam projector of sorts. This works because the FTL drive can't 'steer' - it can only go forwards. This also has the effect of, if a spacecraft should be warping directly towards it, simply slowing it down. Therefore, if it's fired at a craft which is warping directly away from it, it can accelerate it. This can have interesting implications, I'd imagine.
There are also FTL communications. I haven't thought about this very much, except that it has far, far lower energy requirements than the drive, and therefore can practically be made near-instantaneous over very long distances."
I was thinking that the Nexus/Nexum utilized (tweaked) Albecurrie drives, but since I like all human(species) using the same warp method, I might just go with the reverse-engineered Utan FTL.
Well sh*t, I'm 3 minutes late to Aur's explanation. But, yeah, like that.
That's really neat.
The system I had vague thoughts of was something a bit different.
Basically, FTL navigation works by "locking on" to points in a star's gravity well, the most used points being at the north and south poles of the star (known as the "zenith" and "nadir" points) in question and located a distance of 10-20 AUs from the star itself (where the gravity field of the star is weak enough that the warp bubble can form properly, known as a proximity limit). Technically, an FTL-equipped ship can jump anywhere outside a star's gravity well, so technically all of space is a valid jump point with small bubble-shaped exceptions for stars and other bodies with notable gravitational fields. This means you can technically jump into deep space.
Other points can be used as well, but the polar points aren't subject to the interference and risk of collision that is inherent in using points aligned on the planetary plane (where planets and other bodies cause a multitude of minuscule gravitational effects that interfere with FTL travel).
An FTL jump also discharges a large amount of waste heat at the arrival location prior to the ship's arrival, something which is easily detectible to sensors, making it a hopeless proposition to try and jump in undetected at a standard point unless the system is empty, as any competent administration will have sensors at the standard jump points to monitor new arrivals.
Communication while in FTL is impossible, but that's a moot point because FTL jumps are instantaneous (and yes, that combined with the heat thing means FTL is technically time travel, as the heat arrives before you actually jump). Stealthy jumps can technically be done, but that depends on risking the use of nonstandard points deep within the planetary plane and hoping that the thermal energy won't get detected by your enemies.
The risk of "FTL ships jump in, release planet-killer weapon, jump out" is mitigated by the long distances involved: at best, assuming a sun-sized star in the system, the jump point is at 10AU, which is a long time to travel both in and out from the jump points unless sublight engines are wank-tier (i.e. propel ships at a significant fraction of lightspeed, and such). We're talking days of travel time here, assuming ships do about 1% of c, and any ship doing this run will come up against any system defenses anyway.
FTL communications are based in groundside installations and function by essentially using a variant of a normal FTL drive to transmit information through hyperspace, but the energy costs for successful hyperspace transition on a planet in the Goldilocks Zone, even for only data and not thousands of tons of ship, are extremely prohibitive, requiring the installation be hooked up to a dedicated power plant.
E: some additional thoughts
As FTL travel is disrupted by gravity wells, you'll probably have to jump from system to system (through every system on the way to your destination) or risk running into a star between your launch point and destination. This means interstellar warfare likely has frontlines, since you'll almost need to have control of all prior jump points in order to be able to bring up reinforcements and contest a system.
Additional jump points aren't technically everywhere: if you're making a jump into the planetary plane, there's only a few points that are valid, as you can only use points where the gravity wells of various astronomical bodies cancel each other out enough for the drive to do its work. Generally, such points inside the proximity limit will be close to a L1 Lagrange Point, which exists due to the cancellation of gravity between two bodies. These points are also much smaller and less stable than the normal points: rather than only following the star like the zenith and nadir points, these points at least also follow a planet, possibly a planet and moon, and are subject to gravity of other moving objects in the star system.
What do you think?