Question for the math geeks

[phavoc]

I was never good at figuring out how to apply equations to determine volume, so I thought I would tap into those of you who are.

According to the core rulebook, ships travel through jump space in slowly decreasing bubbles of hydrogen that are created when your ship pumps it into the bubble just prior to jump.

So my question is this - if your jump fuel provides X amount of volume of space, would there be any difference in the amount of fuel required if your ship was of a certain configuration. What I mean by this is would it be more effecient to design a ship that had the minimal footprint required? So if you had a 1,000 Displacement ton ship, is it better to have say a boxy shape/sphere, or could you have a very long needle or wedge shape that would take up the same amount of volume.

Now I'm assuming that since we are talking displacement tons for a ship, configuration probably doesn't matter... But like I said, I'm not a math guy so I am not sure if that holds true or not.

Any takers?

 

[rust]

The minimal "footprint" for any volume would be a sphere, but this con-
figuration is somewhat unusual in Traveller - and there ends my Latin.

I think it would depend mostly on whether the "jump bubble" itself has a
specific shape, and how far it has to extend from the surface of the ship.
For example, if a "jump bubble" usually is a sphere with a diameter of 5
kilometers, the configuration of the ship at the center of it does not real-
ly matter, but if the "jump bubble" has to be exactly 17.93 cm thick over
each part of the ship's surface, configuration could play a role. Since we
have no information of this kind, or about the density of the "jump bub-
ble", I do not see how your question could be answered.

 

[GJD]

I seem to recall that a passage somewhere about the jump field extending "about a meter from the ship", which infers it's a wibbly , undluating bubble that follows the shape of the ship, but is a bit bigger in each dimension.

Since DT are a measure of Volume, a 1000 DT sphere has the same volume as a 1000 DT box - 1000 DT. However, saying that the jump feld adds a meter then converts that from a volumetric measurment to a distance measurement.

G.

 

[pasuuli]

It only really matters based on whether it's important for a particular adventure you're playing with a particular group of players... in other words, the jump bubble isn't necessarily "like" a soap bubble in that it minimizes surface area based on tension et al. So probably ship configuration shouldn't matter except when a referee is making it important for a game he's running...

 

[BP]

Ackk! This is an example of why reasoning the way handwaviums 'work' is a bad, bad, bad idea! (Yours is a legitamate question - but if one just says jump takes so much fuel per ton - the question need not exist!)

...So my question is this - if your jump fuel provides X amount of volume of space, would there be any difference in the amount of fuel required if your ship was of a certain configuration.

Nope - the rules define the jump 'fuel' requirements - and they are based on tonnage. (There's a period at the end of that )

If I wanted to 'picture' a 'jump bubble' - I'd probably go with some undulating meta-blob encompassing the entire ship (avoids holes in dispersed structures - like a cut out Borg cube ship) maintained by 'jump fields' which constantly adjust to jump space configurations to maintain a realspace (hydrogen) 'blanket' around the ship - which implies that the density of the hydrogen would be constantly changing... the loss of which to 'jump space' used to explain what the heck happened to all that fuel...

Trying to explain the reasons for how things work that (probably ) don't actually exist just opens up a huge can of worms (I can come up with tons of assumptions and questions from the description I just gave - and contradictions)...

For RP one may need to know things like:
-What happens when something is attached to the ship
-What happens when something leaves the ship during jump
-What happens if something (PP or computer failure say) happens during jump

One could go on to make up 'reasons' for the answers to these questions - but just stating that they are a property of jump should be sufficient - just like the approximate 1 week in jump is stated. (If one reasons this a based on the time it takes the 'bubble' to boil away - then that raises the question of controlling the time by the amount of hydrogen used - or the ships configuration!)

In the RW we have a practically usefull grasp of the mechanics of gravity - but we really have no answers to why it works - and don't need to to know how it works...

Gravity Works! (how? - er - gravitons - er - maybe - hmm -Very Well!)

 

[alex_greene]

If it was a sphere, the diameter of it would likely be the largest dimension of the vessel (typically its length from prow to stern) plus two metres (one metre each end).

So halve that length in metres, add 1, and use the formula for a sphere - 4*(pi*r^3)/3 - to work out the radius of your tiny little self contained universe of a Jump bubble.

 

[phavoc]

Ackk! This is an example of why reasoning the way handwaviums 'work' is a bad, bad, bad idea! (Yours is a legitamate question - but if one just says jump takes so much fuel per ton - the question need not exist!)

...So my question is this - if your jump fuel provides X amount of volume of space, would there be any difference in the amount of fuel required if your ship was of a certain configuration.

Nope - the rules define the jump 'fuel' requirements - and they are based on tonnage. (There's a period at the end of that )

If I wanted to 'picture' a 'jump bubble' - I'd probably go with some undulating meta-blob encompassing the entire ship (avoids holes in dispersed structures - like a cut out Borg cube ship) maintained by 'jump fields' which constantly adjust to jump space configurations to maintain a realspace (hydrogen) 'blanket' around the ship - which implies that the density of the hydrogen would be constantly changing... the loss of which to 'jump space' used to explain what the heck happened to all that fuel...

Trying to explain the reasons for how things work that (probably ) don't actually exist just opens up a huge can of worms (I can come up with tons of assumptions and questions from the description I just gave - and contradictions)...

For RP one may need to know things like:
-What happens when something is attached to the ship
-What happens when something leaves the ship during jump
-What happens if something (PP or computer failure say) happens during jump

One could go on to make up 'reasons' for the answers to these questions - but just stating that they are a property of jump should be sufficient - just like the approximate 1 week in jump is stated. (If one reasons this a based on the time it takes the 'bubble' to boil away - then that raises the question of controlling the time by the amount of hydrogen used - or the ships configuration!)

In the RW we have a practically usefull grasp of the mechanics of gravity - but we really have no answers to why it works - and don't need to to know how it works...

Gravity Works! (how? - er - gravitons - er - maybe - hmm -Very Well!)

Haha! Well, granted, being the game moderator you can do all kinds of things and just say 'because' doesn't really make it a good reason.

After all, we are playing a science-fiction based game. Sometimes you wanna stress a bit on the science so things make sense. I personally like it when they put some logic behind the concept. I know some people just want to play the game, but obviously when they put out design stuff to make your own ships and vehicles, there is enough interest in the 'science' of things. But I'm not saying everything needs to be done at the Striker level....unless you are distributing a design program with it!

 

[BP]

...Haha! Well, granted, being the game moderator you can do all kinds of things and just say 'because' doesn't really make it a good reason.

After all, we are playing a science-fiction based game. Sometimes you wanna stress a bit on the science so things make sense.

Ah - that is the rub - there is no science behind the fiction parts! As with the RW - stressing things in the wrong places just tends to break things... (like common sense and logic!)

Again - the study of Gravity is hard science - and the mechanics work - 'because'.

...I personally like it when they put some logic behind the concept.

Me too! I call it 'game mechanic'. Reasoning - well thats a whole 'nother ball of wax!

Jump logic = requires power which requires fuel; has limited range; 100D safety limit; approx. 1 week transit time.

Now 'injecting high-energy particles into an artificial singularity' - that's not logic - its science based fiction. And its vague enough to be passible (well, ignoring the fact that it is way out of kilter with the TL and weapons otherwise seen in the OTU). Then we start adding more fluff about inflating our newly formed artificial beyond universe 'tiny parallel universe' and folding our 'Jump bubble'... (oops)

Mind - if the blend of science and fiction is good (and the arthors) - details can work. But sometimes the details of things are so shot full of holes that one not only has to suspend belief for the science in the fiction - but also logic and even common sense.

I LOVE details and logic. Put the two together and your right up my alley - don't break science and common sense and I'm smiling and whistling dixie...

Now in the RW I've worked with all kinds of science - from anti-tank weapon systems, to nuclear reactor containment wall inspections, from turbine rotary failure mode simulations, to neural networks and parallel processing (long before they were vogue) - but I have no problem accepting Gravitics and Jump technology in RP and Science Fiction - just 'because'.

 

[alex_greene]

Of course, if somebody in the 1930s had proposed that at some point in the future, a device would be invented no larger than the palm of one's hand which could act as a wireless call-from-anywhere-in-the-world telephone, text communicator, television screen with full streaming live video feeds which you can pause and rewind like a record, diary, virtual cash transactor (look at the design of some modern Japanese vending machines, which can charge your mobile phone's credits rather than your card) and link to a couple of billion paperless documents existing in a vast virtual space of interconnected data held in half a billion multiply - connected beige boxes all over the world ... the authorities would lock you into a rubber room. Particularly if you mention the porn.

One man's impossible is his grandson's normal.

 

[rust]

Of course, if somebody in the 1930s had proposed that at some point in the future (...) the authorities would lock you into a rubber room. Particularly if you mention the porn.

Not really, the early science fiction authors proposed a lot of even more
astonishing stuff, and the porn industry was already doing very well in the
1930s.

 

[alex_greene]

An episode of a contemporary Saturday morning matinee show of the time showed one of the protagonists, ably portrayed by one Buster Crabbe IIRC, toting a rucksack-sized "miniature communicator ..."

Technological concerns aside, I stand by the axiom I posted in the last line.

 

[Infojunky]

And just remember Porn in Traveller just annoys Marc....

 

[BP]

...the porn industry was already doing very well in the 1930s.

Man - that explains the rust - you are old!

Yeah - 1930's might not have been the best example - ironically Irving Gross basically invented wireless communications in the late 30's!

Dates aside - I certainly agree with you. In the context of this thead - I for one was not talking about unbelievability of futuristic technologies - rather over-defined fiction in a roleplay setting that unneccessarily leaves open game mechanic questions and contradictions - such as the one from the OP.

P.S. - I'd extend that saying to 'One man's impossible is another's normal.' , and also might want to specifiy '...palm of an infant's hand' ala this.

 

[alex_greene]

P.S. - I'd extend that saying to 'One man's impossible is another's normal.' , and also might want to specifiy '...palm of an infant's hand' ala this.

Dick Tracy would approve.

And i preferred my quote - it emphasises the increasing technological capabilities of each succeeding generation over its predecessors, a matter close to the heart of Traveller.

 

[phavoc]

Thank you to everyone who responded, if slightly off topic.. Damn you thread hijackers anyway!

I had posted my question because it related to ship design, i.e. do really long slim ships fit the "logic" of the MGT universe. It was one more of curiousity than anything else. I know what the book says, I'm just to make sure I understanding the reasoning on how the arrived at said rule/description. I have found if you have somewhat of an understanding it makes things a lot easier to extrapolate from.

And yes, the game itself takes some suspension of disbelieve. No, we haven't invented an FTL drive, anti-gravity, psionics or even fusion. But we do understand parts of them (cept maybe for psionics), we simply don't have the technology (yet) to build them. A soldier in 1840 with his Winchester Rifle would understand the mechanics of TL8 auto-rifle. It's not really much different, still has a barrel, still shoots at stuff downrange - the basics are still there. Now a tank he might have a harder time conceptualizing.

Still, if anyone from a math point of view could drop an explanation on the volume surrounding an object, and would the shape of a starship affect its jump space volume I would appreciate it.

 

[BP]

...And yes, the game itself takes some suspension of disbelieve.

Nobody implied otherwise - though alex_greene's post did seem to imply it was

...A soldier in 1840 with his Winchester Rifle would understand the mechanics of TL8 auto-rifle. It's not really much different, still has a barrel, still shoots at stuff downrange - the basics are still there. Now a tank he might have a harder time conceptualizing.

Why - its a moving wagon he can't shoot through and has a great big gun? They may not exist to his knowing, but the concept would be a simple one to grasp (additionally note steam locomotives are circa 1830 and cannons were old news by that time). Now if you tell him its made out of single layer thick newspaper and his bullets will dissolve on contact with it - you would probably exceed his 'suspension of disbelief' and he will probably take issue with your sanity! (Just as you would today - although anything is possible - that would seem preposterous to most people - fantasy versus science fiction.)

...Still, if anyone from a math point of view could drop an explanation on the volume surrounding an object, and would the shape of a starship affect its jump space volume I would appreciate it.

The 'volume surrounding an object' would be 'calculated' via integration (digitally or using formulas and calculus) or the summing of the volumes of primitive shapes or differential geometry (Riemannian (sp?) manifolds). If you are assuming a sphere encompassing the entire object (plus a meter each way) then alex_greene has already answered correctly I believe:

If it was a sphere, the diameter of it would likely be the largest dimension of the vessel (typically its length from prow to stern) plus two metres (one metre each end).

So halve that length in metres, add 1, and use the formula for a sphere - 4*(pi*r^3)/3 - to work out the radius of your tiny little self contained universe of a Jump bubble.

Except it should have been volume instead of radius in the last part and the r is equal to the first part (halve that length in meters, add 1).

Since the jump space volume isn't defined in MGT (the +1 meter is an older source - and it doesn't assume a sphere which means the math would be as I stated above) - there is no official answer to your question. You'll have to make that up!

Furthermore, depending on how the density of the 'hydrogen' jump bubble changes as it 'boils' away - the answer could be that the volume changes over the entire course of the 'trip'. Likewise, the folding could mean that the volume is no more than the ship, or volume is irrelevant as the ship has been folded into another set of dimensions.

Since the answer is -> there isn't one - it might be more helpful to know if there is a particular reason/issue behind the question. (Such as whether one can leave the ship/attached items go with the ship to what size...)

Hope this is helpful!

 

[phavoc]

Ah well, I suppose I'll just put this in the "unobtanium" column and just say it works. It's easy, but not the most enjoyable of answers.

Didn't classic (or even Mega) talk about lanthum being used in the outer hulls to create a jump field? I've been looking for my old Starships Operator handbook but I can't seem to find it anywhere. I was hoping to compare it to that and see what it listed. As I recall it had a ton of background explanations for things.

And pie (in most forms) is much tastier than using pi to calculate volume.

 

[BP]

Lanthanum is used in jump drives in other versions (don't know if this is mentioned anywhere in official CT).

I suspect based on official comments regarding detailed systems that additional 'details' on how things like jump drives work will not be forthcoming...

So why don't you just make it up for yourself... with the official definitions left vague enough this is easy to do without breaking 'official' material (one of my points early on).

You define what a 'jump bubble' is! It can be a sphere or ellipse, a sheen of condensate hydrogen, an undulating volume, a multidimensional contortion in the inter-universal foam where alternate universes reside... whatever you want.

Then tack on any mechanics you want (survival roles on exposure or misjump probability when external objects attach to ship). As long as the 'official' rules don't try to get too detailed, nothing breaks unless you want it to.

(Personnally, I prefer pumpkin pi).