The Traveller Ansible (= FTL Comms)

[robject]

This topic discusses the potential for faster-than-light communications (the "ansible") in Traveller -- a largely taboo topic.

EXECUTIVE SUMMARY

A form of ansible is possible in Traveller, but not guaranteed, with the potential discovery of Reality Manipulation at TL27.


TRAVELLER5

Traveller5 lists applications of "fantastic" technology, stretching from TL 22 up to the Singularity, as a service to those of us who read Twilight's Peak and Shadows and WANTED TO KNOW MORE.

One of those technologies is Reality Manipulation -- something we know the Ancients had. (By the way, there are interesting implications of this, since we also know -- if we play by the rules -- that therefore the Ringworld was not built by the Ancients).

Reality Manipulation can be a low-effect phenomenon. In the OTU, reality tends to "snap" back to a center bundle, much like the way a river typically stays its course in non-geologic time. So reality is not really an exponential "fanout". Maybe.

Thus, RM allows absurdity, on the order of Hitchhiker's Guide to the Galaxy. I'm not completely clear on it, but perhaps you could have a message that needs to get to Capital, so an RM device is engaged which shifts reality just to the point where you are ON Capital, and so you deliver your message. Think about it that way, but not too much, as it can lead to insanity.

Detail

In typical fashion, Marc handed out 38 (or so) specific, fantastic tech capabilities, and scattered them among TLs 22-32. Unfortunately for people like me, reaching one of these TLs means you only get ONE of the possible capabilities at that TL. In other words, the tech tree at this point becomes a specific path that winds through one thing your civilization knows, to the exclusion of the rest at that TL.

This is both interesting (your civilization has things others won't) and frustrating (other civilizations have things you won't). The selection is 2D curve-based, so all options are not equally possible, but the number of unique paths to TL32 are, apparently, 3 x 5 x 4 x 4 x 5 x 4 x 4 x 4 x 2 x 2 x 1 = 307,000.

One of those capabilities is Reality Manipulation.


MONGOOSE TRAVELLER

Now we get to the "prototype" ansible found on an Ancient relic ship. The source is Mongoose Traveller's adventure Secrets of the Ancients.

Page 117 introduces the concept:

This ship is vastly more advanced ... it has a prototype ansible – a faster-than-light communication system. This ansible works on a higher level of jumpspace than the one accessible using conventional jump drives, allowing messages to be transmitted over tens of parsecs instantaneously.

1. The novel interpretation of jumpspace might just be what the author had available at the time -- so don't let it hang you up. The nature of the maguffin doesn't affect the adventure at all. Consider the description a fallible witness. This is simply an ansible.

2. Marc was banging out technology issues when SSOTA was published. The book mentions TL21 with the ships in question -- this can be true, as long as one assumes the prototype ansible is a TL25 outlier. So, at least some ship technology must be at TL25.

3. As I've shown, Traveller does have a back-door to potentially allow an ansible, via Reality Manipulation. This is a TL27 technology, so a prototype ansible could be developed at TL25.

 

[whartung]

Sorry, I have no idea what an "ansible" is.

 

[robject]

Good catch. It's faster-than-light communications. Like comms in Star Trek, Star Wars, Babylon 5, where your boss on Terra can phone you up, 5,000 parsecs away, and micromanage your decisions.

 

[whartung]

where your boss on Terra can phone you up, 5,000 parsecs away, and micromanage your decisions.

Ah, good, yes, I need more of this in my life. Long live the promise of future high technology!

 

[whulorigan]

Sorry, I have no idea what an "ansible" is.

A SF-author (I don't remember which one) coined the term as a slang for an interstellar communication system. The term was a corruption of "answerable".

 

[Dulinor]

Ursula K. Le Guin coined it.

 

[mike wightman]

And Orsen Scott Card among others borrowed it.

Ansible - Wikipedia

en.wikipedia.org

 

[mike wightman]

Note that:

Spoiler

In the part of the adventure where the PCs experience the Ancient Empire as it was one of the factions has an ansible network

 

[kilemall]

Hmm, the whole fantastic tech only one branch thing reminds me of the race special ability in the game Cosmic Encounters.

 

[Reban]

Something I've been pondering is the effect of the real world science of Quantum Entanglement.

I know this is OTU but Cepheus Engine Vehicle design guide introduces Quantum Entangled Commuinicators at TL12 and allows their range to increase to a maximum range of Planetary at TL16. Much lower tech level than the Traveller Ansible and much shorter range but still instantanious commuincation. The comms require matched pairs to function but there is an option for a switch exchange linking multiple points.

I could extend this system-wide with a telegraph chain of Q-comm satellites. Potentially I could string them between star systems. Expensive but near instant.

What are the consequences and applications? Interstellar FTL commuinications breaks Traveller (so we are told), so does the relatively short range Q-comm do the same?

Information can outpace the PCs in their ship. Potentially Ansibles and Q-comms mean Travellers can never outrun their reputation or catch up with some important kill order.

One other thought which is way above my INT score; if the Traveller Ansible is a form of Reality Manipulation does it have any interplay with Causality? Does it break causality, sidestep it, or does it have to obey it?

 

[mike wightman]

Communicating FTL using quantum entanglement is not possible according to everything currently known about quantum mechanics and quantum entanglement. One thing it does allow is a much greater level of encryption, so secure communication and un-jammable drone oversight.

 

[robject]

I do remember Marc musing over quantum entanglement as a way to get FTL communication, many moons ago. I was horrified.

 

[mike wightman]

It's a popular sci-fi handwave but demonstrates a total lack of knowledge about the subject.

 

[Condottiere]

Quantum telegraph, maybe.

Lots of cats suddenly dying and reviving.

 

[Drew]

Sorry, I have no idea what an "ansible" is.

Enders Game made use of the ansible.

 

[infojunky]

Ok, does have to be instantaneous communication?

Meaning could there be a speed that a message can propagate faster than physical jump limits but still takes a significant time to arrive.

 

[kilemall]

Ok, does have to be instantaneous communication?

Meaning could there be a speed that a message can propagate faster than physical jump limits but still takes a significant time to arrive.

Some early Trek episodes featured this too remote for instant comms paradigm.

 

[BackworldTraveller]

I looked for the dictionary definition of ansible and have concluded that there needs to be a better one

Ansible as the opposite of sensible, for instance?

The technology exists for an ansible in Traveller at TL9+. The X-Boat network is, to all intents and purposes, a working example. FTL and low bandwidth.

It's just not very portable.

 

[whulorigan]

Ok, does have to be instantaneous communication?

Meaning could there be a speed that a message can propagate faster than physical jump limits but still takes a significant time to arrive.

Or you could do something similar to Larry Niven's Known Space:

In free (unstressed) space "hyperwave" (the FTL comm in his universe) traveled virtually instantaneously (or at least very fast), but could not cross a gravity well (in the case of Known Space, the well for a star was the size of almost the entire star-system). So you transmitted by beamcast radio to a transmitter/repeater at the edge of the gravity well (usually about 5 light-hours) which then encoded and forwarded the message via hyperwave, which was then picked up by a destination system receiver at the edge of its gravity well, which then re-encoded it and sent the message as a beamcast radio signal inbound to the local world.

For an OTU ansible modeled on something like this, it need not travel instantaneously outside a gravity well, but perhaps would travel at a speed just beyond the upper-limit of the fastest speed of the T5 jumpspace-level order (i.e. Jump, Hop, Skip, etc) of the associated transmitter .

 

[Grav_Moped]

Ok, does have to be instantaneous communication?

Meaning could there be a speed that a message can propagate faster than physical jump limits but still takes a significant time to arrive.

There is a way to send a 1-bit signal across the XBoat network at Jump-28 speed, using nothing but the XBoats.
If using J6 Xboats, it'd be Jump-42 speed.

This is based on:
XBoats run daily (from canon).
They don't misjump (at least under LBB2/LBB5).
Parking a ship or other large object on the jump origin point will recall the jumping ship to that point at the end of its 7 days in jumpspace (this is a T5 thing).

The way to send the message is to "step on" the origin point of the XBoat that left 6 days ago. One day later, it's back where it started, with a surprised pilot and a disappointed destination XBoat Tender.

The destination now has the signal -- no XBoat (whatever that's been chosen to mean). That message took 1 day to traverse 4 parsecs. Repeat it down the line for a week, and it's gone 28 parsecs.

As noted, do this with J-6 XBoats and you're sending the signal at Jump-42.

Error-checking/confirmation can be done by recalling the next XBoat as well (low confidence*, but only cuts speed to half), letting one go then recalling the third also (higher confidence, but cuts speed to 1/3), or always sending two boats at once but sending the signal by only recalling one of them (high confidence and full speed, but doubles the cost per link).

Such a message would have to be extremely important and have a pre-designated meaning.


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*there could have been a disruption at the origin that prevented the station from sending an XBoat twice in a row, for reasons unrelated to sending the 1-bit message.