Interstellar Travel
The human-inhabited star cluster where the events of ZARYA-3 take place is a peculiar place – it’s old enough to harbor life-sustaining planets, but somehow its star systems did not disperse across the galactic plane. Contrary – distance between some of them is only 0.5 LY, and the whole core of this cluster is merely 8 LY across.
Still, even with such favorable conditions, interstellar travel on sub-light speeds would take years or even decades to accomplish. Meanwhile near light speed propulsion would require so much energy and come with such immense risks that achieving it could be considered near-fantastical, even if it was possible in the first place.
This reality got completely turned upside down when two institutions on the opposite ends of the human-inhabited space completely independently from each-other came up with a concept of a Subspace Engine. This technology allowed for traversal magnitudes faster then the speed of light while not suffering from any time paradoxes or other side effects of faster then light travel. In mere years the Subspace Engine brought the dawn of humanity as a true pan-stellar species for generations to come.
What Makes a "Good" Space Travel Technology?
All fictional technology has one single purpose – to serve the narrative of the story, be it by making it possible in the first place, or by providing friction that makes it more exciting. So, to “invent” the technology for interstellar travel I wrote down few narrative needs that have to be met by it:
The Universe should feel interesting and exciting. It means that just like in Star Wars each new adventure may feature one or multiple exotic planets with diverse climates and varying levels of development. To fulfill this requirement, the interstellar travel should be not only possible, but mass-adopted, relatively cheap and convenient enough to be used by common people.
But despite the wide adoption of interstellar travel, the Universe of ZARYA-3 should still feel vast and nearly endless. This requirement invites some constrains that keep humans from traveling everywhere across the space. Because a fully explored universe holds no mysteries and thereby will lose its excitement. The most simple approach in this regard is to restrict space travel with three factors: time, fuel and engine integrity.
Lastly, time paradoxes should also be accounted for. In real life, anyone that is traveling with the speed of light becomes “static” in relation to the rest of the universe. It means that any human that is moving faster then light will not age at all meanwhile peers at their origin planet and destination will experience time at their “normal” pace. This effect of time dilation may put a strain on the narrative by making every instance of interstellar travel into a major time jump. So a way to avoid time dilation while moving faster than light should be established.
There are obviously other factors that a hard sci-fi Universe would account for when exploring space travel, like the kinetic energy of a fast moving objects and deadly effects of Hawking radiation. Fortunately, a single solution that is magical enough, but still scientifically plausible can resolve all these problems – enter the Subspace Engine!
The Subspace Engine
The Subspace Engine is a mysterious technology because while it can be freely reproduced and scaled by multiple companies, exact principles behind its function are either lost to the time or were never known in the first place.
The core functionality of the Subspace Engine is based on physical properties of a particle called Deuon (from lat. Deus – god). Deuons are nearly undetectable with modern equipment and are streaming like oceanic currents all across the universe. The speed of Deuons is much faster then of Photons and thereby they are able to travel far beyond the speed of light.
When a spaceship engages its Subspace Engine, it creates a bubble of static space around the ship’s hull. Inside of this bubble the ship and its crew remain still and thereby are not subjected to effects of time dilation. In real space though this bubble of Subspace becomes shrunk to the size of a single Deuon and thereby acquires its physical properties like faster then light acceleration.
This way a spaceship and its crew can travel between the stars without accumulating a time debt or suffering from radiation exposure. There are still constrains though: the Subspace engine has extremely high demands for energy and active cooling to function. Mismanaged wear may leave a ships stranded midway to its destination with no means to call for help.
Another important factor that has to be accounted for is that work of a Subspace Engine can be disrupted by the gravity of larger stellar bodies. It means that a Subspace jump can not be performed anywhere, but the ship has to travel on a sub-light speed far away from any centers of gravity like nearby stars and planets. For this regard, each jump has be carefully plotted with account to the constant stellar movement in order to avoid any obstacles on the way.
During the planned exit to the real space or during emergency shutdown of Subspace Engine, the relative expansion of Subspace bubble inside the real space creates a shock wave. Strength of this explosion is proportional tho the size of the collapsing bubble. This mechanic acts as a very simple failsafe that prevents two different bubbles from expanding inside each other.
Regarding the speed of travel with the Subspace Engine, it is not a constant as the technology may otherwise suggest. While it is true that all Deuons are traversing the space with the same speed, for some reason certain areas of space an angles of jump can increase or decrease the traversal speed. While no hard evidence exist, it is theorized that the reality looks different for Deuons and sometimes they either move along or against invisible cosmic currents. The average speed of the single Deuon makes it travel one light year in around one week of real time.
Given that the average distance between planets in the core of the Human-Inhabited star cluster is 0.5 – 0.7 light years, and the size of core itself is approximately 8 light years across, an average interstellar jump can be just as time consuming as an intercontinental cruise across the ocean. Consequently, the use of Subspace Engine makes it possible to cross the whole core over mere 2 months, but is still too restricted by its capabilities to perform longer voyages outside the human-inhabited cluster.
Other Means of Interstellar Travel
While the Subspace Engine technology seems to invent it’s own laws of physics by manipulating the space and time on a whim, the rest of the Universe of ZARYA-3 is still bound by the fabric of reality. It means that civilizations that do not have access to similar technology have to use other means for interstellar travel.
And here it becomes interesting, because nothing restricts an ancient civilization from discovering a way to reach the speed of 99% C (speed of light) and use this acceleration to “freeze” themselves in time and wait out any threat before “slowing down” into reality a million years later.
And what about other plausible, but less explored physical phenomena, like wormholes that bend space-time and provide instant “teleportation” between distant regions of space? Can wormholes be naturally created by distortions in the fabric of space, or are they artificial constructs? If so then who made them and can more be created? These questions will be explored in the future.
