Interstellar travel is problematic for a number of reasons, but the main one is the sheer distances involved. Most species cannot conceive of such distances in any natural way, and have to resort to analogy or concrete examples to have any hope of placing astronomical numbers into our day-to-day life.

A “light-second” is a unit of distance, rather than time: the distance light travels in a single second when unimpeded by a medium. Even a light-second is ridiculously large on an everyday scale; it’s not until we consider a light-nanosecond that we find something tractable. A light-nanosecond is about 30cm. It takes light less than a billionth of a second to go from one corner of your phone’s screen to the other.

The Sol system is somewhat unusual in its distribution of substellar bodies, but it will serve as an example. The human home planet, Earth, has a single natural satellite Luna, which is a little over 1 light-second away. Earth itself is about 8 light-minutes from Sol, the single star in the system.

The nearest star to Sol is named Proxima Centauri. The two stars are separated by about 4.37 light-years.

What were you doing four years ago?

These incredible distances make direct interstellar transit utterly impractical, even at speeds relatively near the speed of light (which itself is no small feat). Fortunately, our universe does not limit us to such direct travel.

The human model of “Relativity” is one of many superseded by chronodimensional physics, but it provides us a reasonable starting point. From the perspective of an object accelerating in a Relative system, distances are shorter and time passes at a slower rate. At the same time, the effective mass of the object increases, requiring more and more force to continue accelerating.

What appeared to be a “speed limit” in the Relative model turned out to be something much simpler in chronodimensional physics. The decrease in perceived time was the key. Objects in a relative system maintain a constant energy no matter their speed, which implies a constant velocity as well. Acceleration, thus, is not increasing the magnitude of an object’s velocity; it merely redirects some of its kinetic energy from the temporal direction to a spatial one.

If that were the only insight, interstellar travel would still be an impossibility, for we’ve seen that nothing can travel faster (in a Relative system) than the speed of light. What’s necessary is to redirect spatial momentum into the temporal dimension. By doing so, the passage of time relative to the outside world can be hastened. This reduces the required transit time as measured from the destination.

The last piece of the puzzle is transrotation. By realigning a vessel’s dominant axes such that it can provide propulsion along the temporal dimension, voyages through deep space are limited mainly by the relative positions and velocities of the origin and destination in the galactic plane, as well as the structural integrity limits of the ship itself. The product of applied chronodimensional physics is the Galactic Trade Confederation we have today.

Of course, none of this is actually an accurate description of the phenomena of chronodimensional physics, but for a spacer this can serve as a reasonable mental model. Your university professor, however, would likely require much more detail and precision than you will find here.

(It goes without saying, of course, that traveling through a transspace in the vicinity of a significant gravity well will result in near-instant nuclear deterioration. Normal space does have its uses, and after all, it is a rather nice place to live.)

I’m re-reading a book called The Long Way to a Small, Angry Planet, which is about a crew of independent wormhole builders in a universe where such a thing is a contract utility job. One of the reasons I like it is because a lot of it’s about the crew and their interactions in various small situations—kind of Star Trek, or more likely Firefly. It’s not a serious or heavy read, either.

Anyway, re-reading that reminded me of a little story seed I had a long time ago concerning a newly-minted pilot and how he gets into trouble on his very first solo delivery run. I might actually still write it some day (maybe even do pieces of it this month?), but one of the things I had come up with at the time was a pseudo-physics explanation for how faster-than-light travel worked in that universe. This post is an attempt to transcribe that idea, though in doing so I found it a bit more threadbare than I had remembered. (I’m hardly an expert on relativity or even classical physics, so whoo buzzwords! Rotation into a temporal dimension!)

The parts about the speed of light are all accurate, though, including the 30cm light-nanosecond. Famous computer scientist Admiral Grace Hopper used pieces of wire to bring lightspeed into human terms, which works really well.¹

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This entry was posted on March 06, 2015 and is filed under Creativity. Tags: Science, NaCreSoMo 2015