Interstellar communication
23 June, 2009 at 5:47 pm (roleplaying)
I might be running a scifi game some time soon. Aesthetic inspiration: Alien(s)-movies and Terran (meaning humans) in Starcraft. The idea is to make most of technology plausible by current standards; that is, works with logic acceptable by modern humans, but may be significantly more effective.
I don’t intend to engage in any sort of science or technology fetishism, but one little thing has the power to shape societies and gameplay alike, so I’m going to worry a bit about it. That one thing is communication.
So, assuming technology that is plausible by modern standards and some way of taking people to other stars and keeping the people mostly alive in the process by some means (such as self-sufficient spaceships or handwavy stasis; more ideas welcome), how might communication work between different solar systems? How fast and how reliable could it be?
I’m somewhat at a loss here, not being a huge scifi reader or fan. On that note, can anyone recommend some scifi literature with suitable tone? (Other media might work, also, but is likely to be less useful to me.)
Cogito, ergo ludo. 
ScottM said,
23 June, 2009 at 6:44 pm
There’s a huge range of solutions available, depending on the feel you want. If you want an isolated/time delay feel, and your ships travel faster than light, then put a giant computer in the hold of each ship and every time a ship arrives in system it can dump mail and reports from the previous world. CJ Cherryh uses this in her Cyteen books, which makes for a very “pony express” feeling to news.
Ansible technology exists experimentally today; basically, you entangle particles which mirror each other over any distance. This can contribute a very telegraph station feel to a universe, with a few stations having a few dedicated machines for simple messages between worlds.
If your ships are all slower than light, then light speed transmissions– which include everything like radio and TV– are faster than the ships. So you’d have a time lag, but beaming the information would be faster than a ship could carry it.
There are lots of other “handwavium” ways of handling it, depending on the level of communication you want systems to share.
For relatively limited technology and fascinating universes [that are very focussed on the human condition], Ursula LeGuin’s Hanish Cycle is inspirational– though it’s just about “space anthropology”.
Burgeri said,
23 June, 2009 at 7:08 pm
What Scott said.
As for Alien/Aliens, there is no specific description of their communications technology anywhere but from the movies, certain assumptions can be made.
1. Short-range omnidirectional tranceivers. By short range we are apparently still talking about several light years. This is the signal intercepted by Nostromo while travelling at FTL speeds in the first Alien movie. It cannot be heard from Earth but forms a message “bubble” that ships in the vicinity can detect.
2. Long-range ansible. In Aliens, the marines confirm that they have lost contact with LV-146(?) while in the director’s cut the colony manager complains that it takes weeks to get an answer (one week to Earth, one week back). My mental image is that of a tightly directed pulse which sends large amounts of data as a quick burst, which is then dissected, processed and handled. Answers are compressed into a pulse that is then fired back at the colony. While the pulse itself can be huge and contain near-endless amounts of data, the one-week lag over distance makes it more similar to email with attachments than actual real-time communication.
Ambassador said,
24 June, 2009 at 12:16 am
Sourcing to look at for the above:
ansible: Orson Scott Card uses the ansible in much of his science fiction
Many of Charles Stross’ books describe the entangled particle communication process. Because of the cost of shipping sources of entangled particles, it’s prohibitively expensive for many applications and is used primarily for emergencies. Of course, his books in the universe of the Eschaton are a post-singularity, post-scarcity setting.
M Harnish said,
24 June, 2009 at 9:59 am
The now defunct (and hence dirt cheap via Ebay) – Star*Fall RPG setting (for Alternity) provides a similar set of “plausible” FTL communication and travel methods. The whole setting is quite well done and is the supplements are almost completely system agnostic.
Kevin Anderson’s “Saga of the 7 Suns” series also provides an alternative that is somewhat similar to the ansible method involving sentient trees – it’s a cool idea because it puts the power of interstellar communication in the hands of one group.
If you want something decidedly small in scale and rooted even more in hard science fiction, you could go with the Jovian Chronicles setting (from DreamPod 9, also available via Ebay cheaply). If you ignore the anime style and robots, it’s very hard sci-fi limited to our own solar system.
Tommi said,
24 June, 2009 at 8:22 pm
Thanks to everyone for responses (and welcome to the blog, new commenters).
I’m looking into quantum entanglement; maybe expensive, fragile or limited long-range communication as well as more reliable but slowish bursts of information.