Flight Of the Troubadour
“The Universe of the Eighty Squabbling Empires” typically strives for a hard sci-fi feel, but in the name of fun, the distance between the stars has been circumvented by a level of science unto magic.
Most FTL travel is accomplished by travel through what’s become colloquially referred to as “Bubble” space. A network of warp gates guides all interstellar traffic safely through a parallel dimension that links with our own, but uses radically different physics. The most notable being that this dimension is several million times smaller than ours, so that all travel done at seemingly normal speed in the Bubble dimension is well above light in this dimension. Relativity, time dilation, and all the myriad effect normally associated with FTL travel are completely ignored as a result. (Aside from sentient made objects, it would seem that this dimension is also devoid of just about everything else, it is completely dark and empty. The best guess of most physicists is that this micro-dimension is “one knot up or down the string and apparently one end of the rope” in conventional M-theory.) When ships exit B-space they are light years away from where they started depending on how far they traveled while in B-space. Because this network is already set up in most places, navigation between registered friendly planets is a simple matter of getting clearance from the appropriate warp gate traffic controller.
Travel between hostile or ungated planets however must be done with the use of of subspace torpedoes. Where warp gates provide a stable, sustainable breech into bubble space for large amounts of interstellar traffic, subspace torpedoes open slightly less stable, temporary breeches into B-space. Each torpedo comes with a pair of Rift Warheads. The first is used to enter B-space, the second to leave B-space.
Subspace Torpedoes must clear at least 10 km of all metal objects larger than an escape pod or they will not detonate as a safety feature, and therefore cannot be used as weapons, however, the time it takes these torpedoes to reach minimum safe distance is 1 round, therefore characters may attempt to destroy the torpedo (10 hp, Defense 15). Once the rift is open, it is stable for half an hour. The warhead then splits into several pieces shearing open the fabric of space opening a stable 2 dimensional portal in both dimensions with a diameter of 5 km. The pieces, being in dimensional limbo, cannot be targeted. The rift naturally closes once these pieces run out of battery power, unable to sustain the portal.
Also, as a result of the nature of B-Space, opening a second rift anywhere within .1 AU of the first can have unfortunate consequences. Where the distance between 2 feet in B-space may be somewhere around several hundred thousand feet in real space, vice versa is also true. Ships may find themselves co-existing on a quantum level, and then ceasing to exist on any level.
Firing into the rift is a bad idea, as energy weapons entering B-space blueshift considerably in the area where the two dimensions are practically one for the moment, doing ten times their normal damage, (this includes kinetic weapons, as the energy they normally expend on contact with another mass is released) and as the backround cosmic energies are what cause the degradation of the rift in the first place, the application of too much energy in the form of weapons discharge shortens the life span of the rift (1d6 rounds per energy weapon, 1d4 rounds per kinetic weapon hit). It is also for this reason that ships are encouraged not to share rifts, as the discharge from their engines can accelerate this effect as well, and the burden of sustaining the rift with multiple fusion torches passing through it can prove disasterous.
Having a rift collapse is unpredictably terrible. While the boundaries of the rift are incorporeal, a point in space that can no longer agree on which set of physics to use may try to use both (in which case the ship and all on board are simultaneously blue shifted and crushed under their own relativity) or neither (all sorts of hilarious stuff).
Firing a Rift Torpedo in Atmo
…is generally also a bad idea. While the gravity well of a planetary body isn’t a problem (provided a missle meant to be used in vacuum doesn’t crash anyway) the effect of opening a dimensional rift on a planet can still be pretty bad. Because of the void nature of Bubble space, this is a little like breaching the hull of a planet. Air pressure attempts to equalize, and everything gets sucked out into Bubble space in a 5 kilometer tornado for half an hour. On any planet with sentient life, this is considered worse than detonating a nuke, as wide scale bombing with such a device can remove the atomosphere of a planet, rendering it useless to everyone. Opening a rift from B-space to a planet can be equally disasterous, as the gravity well extends through the rift with the full strength of the planet at the appropriate distance. Ships in B-space not cleared for atmo may find themselves hurtling towards a planet ungracefully as engines that were meant only to be used in vacuum struggle to overcome the blowing force of the wind, and the pulling force of the planet. Depending on atmospheric conditions, this adds considerably to all pilot checks and especially navigation checks as the second B-space warhead can be thrown off course.