Some writers pick a fictional world (or worlds) and set most of their stories in it. I have; mine's called the Hidden Frontier, in which FTL travel -- of a difficult and awkward sort -- has been covertly developed at least twice over,* and attempts to use it for strategic purposes have backfired to the extent that there's a whole other human civilization out there, one with whom there is only a shaky peace, after a long, fizzling, inconclusive war. Heck, it may not even be fictional -- I can neither confirm nor deny it.
On the one side, you've got the mildly oppressive minarchy of the Federation of Concerned Spacemen, the Far Edge, "governed" by whoever has the time and the budget; spaceborne Edgers don't look or dress quite like the people next door, or sound like them. Ethnically polyglot, they speak an over-enunciated version of English and dress mostly in mechanical-counterpressure space suits that look like thick full-body leotards or union suits, quite often with a coverall worn over them. Planetbound Edgers, well, they wear work clothes, whatever fits the climate, and they work long, hard and with just as much automated assistance as they can lash up, since there are a lot of mouths to feed and never enough people to grow food. Edgers consider a mild case of OCD an asset, and tend to be overly fond of puns and wordplay. They've been smuggling to and from Earth for decades, usually independent "free-traders" in small (for starships) cargo vessels. Thanks to some serendipitous WW II German tech they picked up on the Moon (a long story that starts with the so-called "Outer Hebrides Agronomy Project" and Project Hoplite and ends in what the Feds called treason) Edger stardrives are somewhat more controllable than anyone else's, and they are able to recover over 80% of the energy used in an FTL "Jump." They're smoother in and out of Jump, too; they guard these secrets with great care. The Edger military is a private contractor, Mil/Space, the only one left from dozens at the start of the War; the "Space Marines" are the end result of some very hard lessons.
On the other side, there's Earth-government-official civilian settlement on a half-dozen worlds, running to the button-down, bowtie, crewcut set for the West and a couple of assorted Russian experiments (Steelworld -- Stalin Mir -- and Novy Russia were both settled by use if dedicated Party members, Zeks terrified into silence, a false history and no children not born on planet; after the Soviet Empire fell, one cut most ties with the Mother Country (and any other), clinging to the illusion; the other (and one more-conventional colony world) are making the best of it, including a rapid-delivery service run in cooperation with the remains of Russian starship program that brings in reasonable income. Meanwhile, France and -- maybe -- Red China are doing their own individual things. Plus there's the military, the United States Space Force and most NATO allies (except France), cut way back since the Treaty of 1989 ended the War; in some ways, they're more like the Coast Guard these days-- well, except for USSF Intelligence, which seems to be everywhere and makes extensive use of reservists.
And that doesn't even begin to cover the stranger corners, like the sunless and independent Smitty's World, or the Edger "City Ships," whatever they are. And oh, yes, too strong a stardrive field will kill you. Prolonged exposure to high but non-fatal levels causes nightmares; a small fraction of people develop an even more unsettling malady in 'Drive: they think they can hear, however vaguely, the $Deity. Or the Heartbeat of the Universe or some such thing. Can they really? I don't know; the Edgers have some drugs that supposedly treat it but generally the feeling does not go away when the ship leaves Jump and repeated exposure eventually overwhelms the sufferer, resulting in a variety of incapacitating symptoms. The only real treatment is to avoid star travel after the initial symptoms appear and hope for the best. --And try to enjoy overhearing the Universe. You might be surprised how many people find it comforting, at least up to a certain intensity.
I haven't posted much over at I Work On A Starship recently and you might think it's because I'm not writing much. Nope -- I'm writing too much. I got stuck on the 2011 Christmas story and I have at least five yarns at varying stages right now.
* FTL drive and the special applications of Heim-Dröscher-Goubau theory to creating and dispersing an Alcubierre drive field or "bubble" may seem like esoteric stuff, but when it is steam-engine time...well, the wheels commence to turn.
6 months ago