Jump (Alliance-Union universe)
Encyclopedia
Jump is a fictional technology
used by spacecraft
in science fiction
author C. J. Cherryh
's Alliance-Union universe
to travel faster-than-light
(FTL). Jump can also be a verb
, and is the act of travelling FTL using jump technology.
Estelle Bok, a physicist
investigating FTL travel, arrived at Cyteen Station
with a group of immigrants
. She continued her research there and achieved a major breakthrough in 2230
when she found a loophole allowing the Einsteinian limit
to be breached. This enabled her to derive the Bok Equation, the theoretical basis for FTL travel. Cyteen management immediately initiated a program to apply Bok's principle to ship drives, and in 2248 the first FTL probe, Aurora, set out from Cyteen Station to Mariner Station, 6.8 light years away, and back.
As news of the FTL technology spread, ships began arriving at Cyteen Station requesting FTL conversions. However, it was not until 2261 that Earth
learnt of these developments and attached top priority to acquiring the new technology. When the technology finally reached Pell Station
in 2262, Earth began studying it, and launched its first FTL warship
in 2266.
(Einsteinian space) and hyperspace
(jumpspace).
Jump takes place between two massive objects, called jump-points, which are generally star
s, brown dwarves
, or "rogue planets"
sufficiently massive to make "pockmark
s" in hyperspace. Prior to jumping, the ship's navigators calculate an outbound vector, targeting the destination jump-point with direction and speed
. The ship accelerate
s along this vector with a long STL burn until it is clear of the present jump-point's gravity well
and the requisite velocity
is reached. The jump engines are then engaged and the ship enters the interface between realspace and hyperspace. In this quasi-state of being half-in and half-out of hyperspace the ship is drawn along the interface to the nearest gravity well on the outbound vector, the destination jump-point. Here it re-enters realspace, travelling at the same speed and direction it entered the interface. Back in normal space the ship dumps velocity by cycling its vanes to graze the interface before the STL thrusters take over. It is possible to pass through several jump-points without slowing down, but this is risky as it can cause the ship's velocity to become uncontrollable.
Calculating the correct outbound vector prior to jumping is crucial, and the mass of the ship and its load have to be factored in. The more momentum
the ship has in jumpspace, the closer to the destination jump-point it will re-appear. Too much momentum could result in it dropping into realspace too close to, or even inside, the destination mass. The ship can also "overshoot" the jump-point with too much momentum and will then drift through hyperspace until a sufficiently massive object is encountered which could drop it "anywhere" in realspace. Not enough momentum, or targeting an object not massive enough to pull the ship out of hyperspace will also leave the ship drifting. A ship's power-to-mass is significant, allowing an unloaded ship to travel faster in jumpspace than a loaded ship of similar design, even enabling the former to "over-jump" the latter. Warships have high power-to-mass ratios, making them fast despite their size. If another ship happens to be at your ship's re-entry point, both ships will be destroyed.
In theory it is possible to jump "any" distance, but the practical limit is about ten light-year
s. Calculating trajectories
beyond a certain distance become too unreliable because of the unpredictable nature of n-dimensional hyperspace. Over short distances the calculation discrepancies are negligible, but over longer distances, the errors multiply. In addition, there is the interference of nearby stars that are likely to alter the intended trajectory.
Contrary to other "jump technologies", jump in the Alliance-Union universe is not instantaneous. However, just how long a ship actually spends in jumpspace is difficult to gauge because jump-time (also called "no-time") is not real-time. But sufficient time does elapse for minor injuries on "tranked" (tranquilized) crew's bodies to heal and for "night-walkers" to move about the ship. Typically subjective time aboard a ship in jumpspace can vary from a few days to several weeks.
effects of jump is time dilation
, that is, time slows down for objects in motion relative to those at rest, and the faster the object moves, the more pronounced the effect. Crew that spend much of their time aboard spaceships that jump frequently age slower than space station personnel and this gives rise to the notion of "ship-time" and "station-time" (or "Universal time"). A navigator on a merchant ship may be 30-years old ship-time, but considerably older in terms of station-time. To resolve this dilemma, a person's "true age" is calculated with medical computers using parameters
such as what ships he or she has been on, what routes these ships took, and what load they carried.
. Most humans experience extreme psychological distress, potentially resulting in madness, and need to "trank down" or tranquilize themselves prior to each jump. The oxygen-breathing species native to Cherryh's Compact space, with the exception of the Stsho, do not require drugs during jump as their bodies naturally enter a deep sleep. However, some species in the Alliance-Union universe can function normally during jump and require little to no assistance.
For humans, the jump from realspace to hyperspace is perceived as the ship (and themselves) coming apart, and it became necessary to develop "trank-packs" that administer tranquilizers to the crews of FTL ships prior to jumping. Tranking down puts the crew into a quasi-sleep state for the duration of the jump, leaving them only marginally aware of their surroundings. "Nutri-packs" were also developed to provide essential sustenance for the crew upon waking after system re-entry, as jumps can sometimes last up to a few weeks of "no-time", leaving them extremely hungry, thirsty and nauseated.
Ships with tranked crews are always at their most vulnerable when they drop back into realspace. The crew is groggy and slow reacting to the current status of their ship and the possible presence of other ships in the vicinity.
(1994).
Night-walkers who are also navigators, like Capella, are valued because they are awake on re-entry into realspace and can therefore react quicker than crew still recovering from trank. They can also sometimes "hear" potential problems while in hyperspace, for example the presence of an enemy ship. However, they can't navigate the ship, as their computers do not work in hyperspace. But aside from just listening, they sometimes amuse themselves by wandering around the ship and entering tranked crewmates' rooms.
Fictional technology
Fictional technology is proposed or described in many different contexts for many different reasons:*Exploratory engineering seeks to identify if a prospective technology can be designed in detail, and simulated, even if it cannot be built yet - this is often a prerequisite to venture capital...
used by spacecraft
Spacecraft
A spacecraft or spaceship is a craft or machine designed for spaceflight. Spacecraft are used for a variety of purposes, including communications, earth observation, meteorology, navigation, planetary exploration and transportation of humans and cargo....
in science fiction
Science fiction
Science fiction is a genre of fiction dealing with imaginary but more or less plausible content such as future settings, futuristic science and technology, space travel, aliens, and paranormal abilities...
author C. J. Cherryh
C. J. Cherryh
Carolyn Janice Cherry , better known by the pen name C. J. Cherryh, is a United States science fiction and fantasy author...
's Alliance-Union universe
Alliance-Union universe
The Alliance-Union universe is a fictional universe created by science fiction and fantasy author C. J. Cherryh. It is the setting for an epic future history series extending from the 21st century out into the far future....
to travel faster-than-light
Faster-than-light
Faster-than-light communications and travel refer to the propagation of information or matter faster than the speed of light....
(FTL). Jump can also be a verb
Verb
A verb, from the Latin verbum meaning word, is a word that in syntax conveys an action , or a state of being . In the usual description of English, the basic form, with or without the particle to, is the infinitive...
, and is the act of travelling FTL using jump technology.
Development of FTL travel
In 2220,Estelle Bok, a physicist
Physicist
A physicist is a scientist who studies or practices physics. Physicists study a wide range of physical phenomena in many branches of physics spanning all length scales: from sub-atomic particles of which all ordinary matter is made to the behavior of the material Universe as a whole...
investigating FTL travel, arrived at Cyteen Station
Cyteen
Cyteen is a Hugo Award-winning science fiction novel by C. J. Cherryh set in her Alliance-Union universe. The murder of a major Union politician and scientist has deep, long-lasting repercussions....
with a group of immigrants
Immigration
Immigration is the act of foreigners passing or coming into a country for the purpose of permanent residence...
. She continued her research there and achieved a major breakthrough in 2230
when she found a loophole allowing the Einsteinian limit
Special relativity
Special relativity is the physical theory of measurement in an inertial frame of reference proposed in 1905 by Albert Einstein in the paper "On the Electrodynamics of Moving Bodies".It generalizes Galileo's...
to be breached. This enabled her to derive the Bok Equation, the theoretical basis for FTL travel. Cyteen management immediately initiated a program to apply Bok's principle to ship drives, and in 2248 the first FTL probe, Aurora, set out from Cyteen Station to Mariner Station, 6.8 light years away, and back.
As news of the FTL technology spread, ships began arriving at Cyteen Station requesting FTL conversions. However, it was not until 2261 that Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
learnt of these developments and attached top priority to acquiring the new technology. When the technology finally reached Pell Station
Downbelow Station
Downbelow Station is a science fiction novel written by C. J. Cherryh and published in 1981 by DAW Books. It won the Hugo Award in 1982, was shortlisted for a Locus Award that same year, and was named by Locus Magazine as one of the top 50 science fiction novels of all time in 1987.The book is set...
in 2262, Earth began studying it, and launched its first FTL warship
Warship
A warship is a ship that is built and primarily intended for combat. Warships are usually built in a completely different way from merchant ships. As well as being armed, warships are designed to withstand damage and are usually faster and more maneuvrable than merchant ships...
in 2266.
Mechanics of jump
In the Alliance-Union universe faster-than-light (FTL) ships have two major drive systems, slower-than-light (STL) thrusters and FTL jump engines. The jump engines comprise vanes that are attached to the outside of the ship. When the vanes are pulsed, they generate gravity waves which create a field, or "bubble", around the ship that pulls it (and anything else in the field) along the interface between realspaceMinkowski space
In physics and mathematics, Minkowski space or Minkowski spacetime is the mathematical setting in which Einstein's theory of special relativity is most conveniently formulated...
(Einsteinian space) and hyperspace
Hyperspace (science fiction)
Hyperspace is a plot device sometimes used in science fiction. It is typically described as an alternative region of space co-existing with our own universe which may be entered using an energy field or other device...
(jumpspace).
Jump takes place between two massive objects, called jump-points, which are generally star
Star
A star is a massive, luminous sphere of plasma held together by gravity. At the end of its lifetime, a star can also contain a proportion of degenerate matter. The nearest star to Earth is the Sun, which is the source of most of the energy on Earth...
s, brown dwarves
Brown dwarf
Brown dwarfs are sub-stellar objects which are too low in mass to sustain hydrogen-1 fusion reactions in their cores, which is characteristic of stars on the main sequence. Brown dwarfs have fully convective surfaces and interiors, with no chemical differentiation by depth...
, or "rogue planets"
Interstellar planet
A rogue planet is a planetary-mass object that has been ejected from its system and is no longer gravitationally bound to any star, brown dwarf or other such object, and that therefore orbits the galaxy directly...
sufficiently massive to make "pockmark
Pockmark
Pockmark may refer to:*acne scarring — resulting from acne or infections such as chicken pox* the scarring of smallpox*Pockmark — a geological formation...
s" in hyperspace. Prior to jumping, the ship's navigators calculate an outbound vector, targeting the destination jump-point with direction and speed
Speed
In kinematics, the speed of an object is the magnitude of its velocity ; it is thus a scalar quantity. The average speed of an object in an interval of time is the distance traveled by the object divided by the duration of the interval; the instantaneous speed is the limit of the average speed as...
. The ship accelerate
Acceleration
In physics, acceleration is the rate of change of velocity with time. In one dimension, acceleration is the rate at which something speeds up or slows down. However, since velocity is a vector, acceleration describes the rate of change of both the magnitude and the direction of velocity. ...
s along this vector with a long STL burn until it is clear of the present jump-point's gravity well
Gravity well
A gravity well or gravitational well is a conceptual model of the gravitational field surrounding a body in space. The more massive the body the deeper and more extensive the gravity well associated with it. The Sun has a far-reaching and deep gravity well. Asteroids and small moons have much...
and the requisite velocity
Velocity
In physics, velocity is speed in a given direction. Speed describes only how fast an object is moving, whereas velocity gives both the speed and direction of the object's motion. To have a constant velocity, an object must have a constant speed and motion in a constant direction. Constant ...
is reached. The jump engines are then engaged and the ship enters the interface between realspace and hyperspace. In this quasi-state of being half-in and half-out of hyperspace the ship is drawn along the interface to the nearest gravity well on the outbound vector, the destination jump-point. Here it re-enters realspace, travelling at the same speed and direction it entered the interface. Back in normal space the ship dumps velocity by cycling its vanes to graze the interface before the STL thrusters take over. It is possible to pass through several jump-points without slowing down, but this is risky as it can cause the ship's velocity to become uncontrollable.
Calculating the correct outbound vector prior to jumping is crucial, and the mass of the ship and its load have to be factored in. The more momentum
Momentum
In classical mechanics, linear momentum or translational momentum is the product of the mass and velocity of an object...
the ship has in jumpspace, the closer to the destination jump-point it will re-appear. Too much momentum could result in it dropping into realspace too close to, or even inside, the destination mass. The ship can also "overshoot" the jump-point with too much momentum and will then drift through hyperspace until a sufficiently massive object is encountered which could drop it "anywhere" in realspace. Not enough momentum, or targeting an object not massive enough to pull the ship out of hyperspace will also leave the ship drifting. A ship's power-to-mass is significant, allowing an unloaded ship to travel faster in jumpspace than a loaded ship of similar design, even enabling the former to "over-jump" the latter. Warships have high power-to-mass ratios, making them fast despite their size. If another ship happens to be at your ship's re-entry point, both ships will be destroyed.
In theory it is possible to jump "any" distance, but the practical limit is about ten light-year
Light-year
A light-year, also light year or lightyear is a unit of length, equal to just under 10 trillion kilometres...
s. Calculating trajectories
Trajectory
A trajectory is the path that a moving object follows through space as a function of time. The object might be a projectile or a satellite, for example. It thus includes the meaning of orbit—the path of a planet, an asteroid or a comet as it travels around a central mass...
beyond a certain distance become too unreliable because of the unpredictable nature of n-dimensional hyperspace. Over short distances the calculation discrepancies are negligible, but over longer distances, the errors multiply. In addition, there is the interference of nearby stars that are likely to alter the intended trajectory.
Contrary to other "jump technologies", jump in the Alliance-Union universe is not instantaneous. However, just how long a ship actually spends in jumpspace is difficult to gauge because jump-time (also called "no-time") is not real-time. But sufficient time does elapse for minor injuries on "tranked" (tranquilized) crew's bodies to heal and for "night-walkers" to move about the ship. Typically subjective time aboard a ship in jumpspace can vary from a few days to several weeks.
Disappearances
If a ship fails to return to realspace, whether through pilot error, or some other failing, it remains in hyperspace, lost permanently. Only one of Cherryh's novels, Port Eternity (1982), deals with this, although it is unclear when in the Alliance-Union timeline it takes place, except that it is after the establishment of the Alliance and Union and occurs in Union-side space.The Knnn
The technologically advanced and enigmatic methane-breathing Knnn from Cherryh's Compact space are the only known species that can change a ship's vector during jump. Knnn ships also have the ability to jump together in synchronisation, sometimes up to a dozen at a time. A single jump-field is created around all the ships and they are pulled into hyperspace as a unit. The Knnn sometimes use this ability to transport ships of other species through jumpspace. They cluster around an unsuspecting vessel, create a single jump-field and haul the ship with them.Time dilation
One of the relativisticRelativistic particle
A relativistic particle is a particle which moves with a relativistic speed; that is, a speed comparable to the speed of light. This is achieved by photons to the extent that effects described by special relativity are able to describe those of such particles themselves...
effects of jump is time dilation
Time dilation
In the theory of relativity, time dilation is an observed difference of elapsed time between two events as measured by observers either moving relative to each other or differently situated from gravitational masses. An accurate clock at rest with respect to one observer may be measured to tick at...
, that is, time slows down for objects in motion relative to those at rest, and the faster the object moves, the more pronounced the effect. Crew that spend much of their time aboard spaceships that jump frequently age slower than space station personnel and this gives rise to the notion of "ship-time" and "station-time" (or "Universal time"). A navigator on a merchant ship may be 30-years old ship-time, but considerably older in terms of station-time. To resolve this dilemma, a person's "true age" is calculated with medical computers using parameters
Parameter (computer science)
In computer programming, a parameter is a special kind of variable, used in a subroutine to refer to one of the pieces of data provided as input to the subroutine. These pieces of data are called arguments...
such as what ships he or she has been on, what routes these ships took, and what load they carried.
Disorientation
Jump is a disorientating experience for those using it, although the degree of discomfort varies depending on the speciesSpecies
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
. Most humans experience extreme psychological distress, potentially resulting in madness, and need to "trank down" or tranquilize themselves prior to each jump. The oxygen-breathing species native to Cherryh's Compact space, with the exception of the Stsho, do not require drugs during jump as their bodies naturally enter a deep sleep. However, some species in the Alliance-Union universe can function normally during jump and require little to no assistance.
For humans, the jump from realspace to hyperspace is perceived as the ship (and themselves) coming apart, and it became necessary to develop "trank-packs" that administer tranquilizers to the crews of FTL ships prior to jumping. Tranking down puts the crew into a quasi-sleep state for the duration of the jump, leaving them only marginally aware of their surroundings. "Nutri-packs" were also developed to provide essential sustenance for the crew upon waking after system re-entry, as jumps can sometimes last up to a few weeks of "no-time", leaving them extremely hungry, thirsty and nauseated.
Ships with tranked crews are always at their most vulnerable when they drop back into realspace. The crew is groggy and slow reacting to the current status of their ship and the possible presence of other ships in the vicinity.
Night-walkers
A "night-walker" is someone from a species that normally sleep during jump (naturally or via trank) who have learnt to function normally while in jump-time. They embrace this alternate reality, with all its unworldly shapes and sounds, and believe there are new "worlds" to be found out there. New jump-points and routes are often discovered by night-walkers. Notable night-walkers in Cherryh's Alliance-Union universe include Chur Anify (hani) in Chanur's Homecoming (1986), Hallan Meras (hani) in Chanur's Legacy (1992), and Capella (human) in TripointTripoint (novel)
Tripoint is a science fiction novel written by the United States science fiction and fantasy author C. J. Cherryh, and was first published by Warner Books in September 1994. It is one of Cherryh's Merchanter novels and is set in the author's Alliance-Union universe.-Background:In the Alliance-Union...
(1994).
Night-walkers who are also navigators, like Capella, are valued because they are awake on re-entry into realspace and can therefore react quicker than crew still recovering from trank. They can also sometimes "hear" potential problems while in hyperspace, for example the presence of an enemy ship. However, they can't navigate the ship, as their computers do not work in hyperspace. But aside from just listening, they sometimes amuse themselves by wandering around the ship and entering tranked crewmates' rooms.
See also
- Alliance-Union universeAlliance-Union universeThe Alliance-Union universe is a fictional universe created by science fiction and fantasy author C. J. Cherryh. It is the setting for an epic future history series extending from the 21st century out into the far future....
- The technology of the Compact
- Faster-than-lightFaster-than-lightFaster-than-light communications and travel refer to the propagation of information or matter faster than the speed of light....
External links
- C. J. Cherryh's home page. Alliance/Union Chronology.
- Everything2. Jumpship.
- Well of Souls. FTL Technology & Tactics (jump technology used in the Outsider comic).