If you've spent any time in the universe of Inherit the Stars or Farewell Andromeda (same universe, 200 years later), then you'll probably remember the references to Dark Energy Drive and DEDspace. But what exactly does that mean?
Like most of my fictional technology, it was based on solid foundation of research with a liberal application of imagination.
You see, in order for certain plot elements in the two stories to work, I had to create some sort of travel or propulsion system that could span vast distances of space (roughly 25,000 light years) in a very short period of time. Just to put that in perspective, our outgoing Voyager sister probes, launched in August and September, 1977, have been traveling outbound for nearly 40 years and have just recently passed beyond the edges of our very own solar system. If they were to reach the nearest star to our own Sun (Alpha Centauri at a mere 4.3 light years away), provided they were even traveling in that direction (which they aren't), it would take tens of thousands of years.
Well, what about New Horizons, the much more advanced probe launched in 2006 that just gave us those spectacular first looks at Pluto after traveling 9-1/2 years to get there at some 36,373 mph (or 58,536 kph). Faster yes, but it would still take NH another 40,000 years to reach Alpha Centauri. Forty thousand years just to reach our neighboring star. And that's at a speed of nearly 37,000 miles per hour!
How about a Space Shuttle? They were really fast, right? Ha! The shuttles traveled at a paltry 17,600 mph. Plan on 165,000 years to reach Alpha Centauri. (Check out: EarthSky.org: Travel Time to Alpha Centauri)
So yeah. Wow! The distances we're talking about are mind-blowing. I had to find a much faster--or more inventive--way to get around the neighborhood in the 35th century and beyond.
Even with the star-hopping that their decidedly advanced technology can manage, allowing them to travel system-to-system in a matter of days and span a number of systems inside a couple of weeks, we're talking months of travel to reach the outlier points of the Milky Way, which is one of their destinations in both stories. And that just wouldn't work. I had to find some form of "Galaxy Express" transit.
And Dark Energy provided that magic carpet.
You see, scientists aren't even sure what Dark Energy is just yet. Only that, in theory, it must exist in order for the universe to work, along with Dark Matter. We can't see it. We can't sense it. We only know that, mathematically, there's something dark and mysterious out there, and it accounts for nearly 68% of the actual universe. Dark Matter makes up an additional 28%.
Nearly ninety-six percent of the universe may be Dark Energy and Dark Matter!
That's a whole lot of something that's nothing!
You see, in order for galaxies to not spin apart, there has to be something they call Dark Matter that accounts for the mass and the gravity that holds it all together, and in order for observations from deep space (which also means deep time) to make sense, there also has to be something stretching the universe apart--and they dubbed that Dark Energy. In tandem, Dark Energy and Dark Matter create the theoretical dynamics that might explain how the universe functions as it does when normal mathematics say it shouldn't function at all. (I'm paraphrasing here.)
When I started researching Dark Energy, the theory that made the most sense to me is that Dark Energy actually exists in another unknown dimension. Okay, I can get my head around that. (And better yet, my muse seemed to latch onto the idea big time.) I'd read theories that some scientists believe there could be up to nine dimensions--though trapped in our mortal bodies, we're only programmed to function within three--height, width, depth. Or maybe four, if you consider time a dimension onto itself.
So Dark Energy may form another dimension--one that we could actually enter if we found a way and a means to access it. And in doing so, we might be able to span huge distances in space by slipping the surly bonds of 3D. But...there's also Dark Matter, which some scientists believe might even provide a galaxy-wide transport system. Other experts are exploring the idea that Dark Energy and Dark Matter are connected. (In my universe, they are, and the combined phenomena is simply referred to as DEDspace, meaning Dark Energy Dimension space.)
Fifteen hundred years in our future, a man named Zaviar Mennelsohn did (or will) discover a way to access DEDspace. Or at least, he will in The Inherited Stars universe.
But DEDspace is not fun. It takes an iron constitution to pilot in the Great Nothing. It alters the senses and perceptions, and it's downright painful for crew and passengers alike. So it's not a practical way to travel from point A to point Z, even if it is a necessary one. And that's the reason DEDspace isn't exactly a popular place to be in The Inherited Stars universe, and DEDspace travel isn't at all commonplace.
That's why most of the subspecies that inhabit these stories just stick to their system-hopping drives, thank you very much.
More About Dark Matter and Dark Energy (for Those Who Dare)
The Universe's Dark Matter and Dark Energy