Jump Theory 101

[Scott Martin]

Sigg:
FF&S (1) page 42 requires surface area for jump drives (1 square meter per 3 cubic meters of volume) Presumably this is for a jump grid, so TNE *does* require a jump grid.

I though that T4 retained the TNE fuel requirements: I dumped most of it as a technical archietecture due to sensor issues, so I never actually built a ship with it (I did see that it uses surface area for J-Drives though)

See the below post for an explanation of the design philosophy explanation for "fixing" the 3I capital ships: I bet it's a lot easier to retrofit a jump grid onto a battleship than to build them all 20% oversize... It also (partially) explains the "fashion" in T4, since the "Empire" as described has no peers (or major threats)
__________________________

Bill

My Bad, I need to remember to put <sarcasm> tags in when I'm talking about "dangerous" opponents like the Vargr. I believe that other folks have pointed out how unlikely it would be that the (Tl-12) vargr would pose a significant threat to even the "reserve" (TL-14) IN fleet units in corridor.

My attempted slant for CT was that the higher fuel requirements were "margin" for allowing a ship to jump un-gridded. I also called this a "fad" which made its way into the IN design process as a functional specification required either by some set of Imperial bureacrats who couldn't find a jump drive with it lodged firmly in their... ledger sheet, or by a special interest group (led by say, Archduke Exxon). While this is common in *any* era's administration, it tends to be rampant in the decline of an Empire. In a time of relative "peace" idiots can do this without it having an apparent effeect on actual readiness levels. The rest of your comments are pretty much bang on. "Border Skirmishing" is not the same as "Major War" and tends to need a different mix of fleet units (more lighter combatants, less "Heavy Metal". For an example of this you can look at the change in British naval composition after the end of the Napoleonic war)

I'll try give an example instead. If you are an admiral in the 3I during the "golden years", and you know that you need "x" number of hulls to cover the border if the penny drops, you're going to be willing to accept some comprimises to keep your funding levels. If the *only* way that the appropriations bill will be approved is if you agree to build your ships in a way that gratiutiously wastes fuel (bill sponsored by Archduke Exxon, Duke Shell and Duke Mobil) will you accept the compromise to get the hulls? If not, are you willing to accept the loss of life in the first few months of an enemy offensive when you are caught without enough units to cover your assigned station?

In a shooting war you are in a position to point out how stupid this is, and hope that it cripples the carrers of the idiots. Unfortunately "political" considerations tend to dominate in times of peace while operational realities are only noticed in times of war. When folks realize that those naval appropriations are what's keeping them alive they stop treating them a "diversion" from their (insert finger-painting waste of taxpayer dollars here). Unfortunately "Finger-painting" is often positioned as "an economically essential activity" in a peactime culture. Any time politics trumps reality you have a culture with potential problems.

IMO requiring hulls that waste this much tankage is incredibly stupid: you are in effect requiring a design that can take 100% surface damage without affecting jump operation, and most vessels will be out of action LONG before that, especially in a "meson dominant" theater. The "savings" in cost for not adding the jump grid are probably offset in additional fuel consumption *in the first year*. The *only* time you are going to see this is in an empire in decline which feels that it has no real external threats (or even serious competition) which (IMO) describes the attitude of the 3I to a tee.

<Politics>
This mindset also describes issues with equipment issued to the US forces at the beginning of the latest "police action" in the Gulf. If you are going to commit troops to a conflict, you should probably listen to the soldiers fought the last war if you want a frank assessment of what is needed to fight the next one. Apologies since this isn't the political pulpit, but it does underscore the point rather well: "You fight a war with the army you've got, not the one you want"
</Politics>
If you disagree with the above (politics) please feel free to flame me via PM, let's try not to clutter up this thread

Scott Martin

 

[Whipsnade]

Originally posted by Scott Martin:
If you disagree with the above (politics) please feel free to flame me via PM, let's try not to clutter up this thread

Scott,

A procurement scandal in a sector or three I can buy. The 'fix' being in at a couple IN design bureaus is entirely possible. We have the example of General Shipyards after all. The same level of corruption and/or idiocy across 11,000 systems? Sorry, but not IMTU because we also know General Shipyards doesn't build for the IN anymore.

It was a neat suggestion, killed two birds with one stone and all that. It just doesn't fit IMTU and, I'd suspect, it wouldn't fit in the OTI either.

First; there are no 'fuel' megacorps and no whiff of megacorp intrigue concerning starship fuels in the OTU. The idea that someone would find it worth their while to bribe enough of the IN brass to design 'fuel-hungry' designs across 11,000 systems and 23 sectors when fuel can essentially be scooped for free is silly.

Go ahead and bribe all the IN admirals to build a 'fuel-hungry' fleet, now explain why civilians - especially megacorps who routinely cut each others' throats over market share - are 'wasting' money on building 'fuel-hungry' designs too.

Second, you bring up the well known human trait of fighting the next war with the last war's ideas and/or equipment. I happen to agree that such an idea can be applied in general terms, during peace time 'inertia' will be the norm with the occasional breakthrough.

However, if such equipment inertia or operational inertia exists - and I think it does, please then explain why CT's 5th FW was fought with 'fuel-hungry' designs in 1110 and MT's Rebellion was fought with 'fuel-lite' designs in 1117.

Was the entire Fleet rebuilt in seven years? We know each faction fought primairly with pre-Rebellion assets and had significant troubles making good their losses once the fighting began. Why are the Rebellion fleets suddenly and magically 'fuel-lite' instead of 'fuel-hungry'?

You answer doesn't work IMTU. If it works in your and any other TU, that's great. Have fun using it. It doesn't in mine however.

By the way, your answer doesn't fail because it is 'your' answer. It fails because I cannot make it and it's follow on consequences fit well enough into canonical information. That's the trouble with 'handwaves' of this sort, they 'solve' a single problem here while causing other problems there. I've heard it likened to wrestling with a balky piece of sheet metal; you line it up to fit a few holes 'here' and then find it cannot fit all these other holes 'there'.

Your gridded fuel-lite drive, non-gridded fuel-hungry drive, and the explanations behind each fit very well 'here' but they also fail to fit 'there' and 'there' and 'there'.

I have no answer to the jump grid conundrum. No in-game asnwer that is. My meta-game answer to the problem is that GDW relinquished day-to-day editorial control of Traveller to DGP and DGP made several mistakes in continuity.

Until there is an answer that fits both 'here' and 'there' - and IMEHO your's does not - I'll simply ignore jump grids IMTU. What others do in their TUs is their concern.

Thanks for the ideas, especially the gravity link that now lets me tie in 'tidla' jump limits.


Have fun,
Bill

 

[Ptah]

Hi all, late to the party. I'd posted a bit of Jump Theory IMTU here:
http://www.travellerrpg.com/cgi-bin/Trav/CotI/Discuss/ultimatebb.cgi?ubb=get_topic&f=7&t=000346#000000

It is definitively not canon, a good portion was developed before the existance of canon material.

You'll see I've little knowledge of post CT details, I mistakenly thought the jump grid was made of iridium instead of lanthanum. After the dicussions here I think IMTU it will be of any suitable superconductor, the term lantahnum grid being a common reference to the lanthanum based superconductor used in the earlier days of jump drive IMTU.

More aspects of Jump Theory IMTU not in the referenced link:

Theoretical Origins of Jump Theory
IMTU the theory of jump drive derives from the same theories that explain gravatics, or in the case of those crazy humans, jump drive theory was discovered before the theory for gravatics and the theory of jump lead to the theory of gravatics. Non-terrans IMTU will recall that humans also developed nuclear weapons at TL5, a full three TLs before most all other species.

Details on the Jump Field
The jump drive projects a "field" around the ship and allows the channeling of all of the energy produced by the drive into jump space. The jump drive and power plant are integrally connectd to permit this, making the mounting of a back up jump drive near impossible and at the very least incredibly expensive.

The jump drive field initially establishes a weak connection to jump space. Proper “modulation/control” of this field allows for greater and greater amounts of energy to be poured into jump space through the jump field. Nothing happens in real space until a critical point is reached at which time the volume in real space within the jump field instantly vanishes (on the Planck time scale) into jump space.

Jump Signatures
The term field is not a proper one to describe a jump field within most TL8 physics but is common nomenclature. Measurements indicate that the “shell” created by the field is truly one dimensional within the limits of quantum mechanics. The “jump flash” sometimes observed is from particles that due to quantum uncertainty in position have a substantially equal probability of being both inside and outside the jump field upon transisition into jump space. On jump space entrance, some of these particles are drawn into the void left by the departing ship at relativistic speeds where collisions produced x-ray etc. radiation. On jump emergence, particles within the jump sphere are drawn into jump space, those at the edge are pushed out at relativistic speeds. Otherwise, the only signature of a jump drive is the creation of a gravitational wave. Detailed analysis of this wave can provide details on ship size and point of origin. It is postulated IMTU that tachyon emissions preceed both jump entrance and emergence. Some theories predict by a substantial amount of time. Unfortuantely, such tachyons are not observable at TL15.

Jump Fuel Use
IMTU 90% of jump fuel consumption is used to enter and leave jump=space. The remaining 10% is used to maintain the jump field in jump space.

Anyway, another 2 Cr to the pile.

 

[Scott Martin]

Hey Bill

No Problem at all: my offered explanation was the best I could come up with that was better than "the game designers had issues" I was also trying to solve the "Commercial designs don't work below TL-15" problems, but on reflection those issues were mostly in MT, not CT.

Unfortunately it still leaves big continuity holes, which (unfortunately) tend to fragment the player base and cause doctrinal "holy wars". I still think that the best way to deal with this is to put out an excellent product for T5, but after so many "false starts" (especially from the point of view of die-hard CT players) it's going to be really hard to acoomplish that. Maybe TNE could have done that, but (IMO) the setting was poor: I think that a "Renniasance" setting would have better served the franchise than "Twilight 5300". This is not a slight at the TNE writing team, who (again IMO) did a good job on the setting, it's just not a setting that I ever had any interest in playing in.

I don't think that we are likely to come up with a solution that unifies *all* players, but I think that it's wort a shot to try. The worst that happens is that we are back where we started

BTW you do make an excellent devil's advocate. My solution to the issue has been to simply ignore the differences between TNE and CT fuel use and assume that it is a different system. Not an "elegant technical solution" but it works for me.

Scott Martin

 

[Whipsnade]

Originally posted by Scott Martin:
BTW you do make an excellent devil's advocate.

Scott,

That I do.

A few folks have suggested I change my 'name' here to "Devil's Advocate" but, after being stuck with a pseudonym through the TML for over four years, I'm glad to be using my actual name instead.

Because of this, I'm often misinterpretated and my rapid posting style doesn't help things either. It leads to effects I by no means intend to cause but most certainly cause all the same.

OTOH, I do get a LOT of 'script doctor' work on the side. Not to mention any names but currently I'm privately 'helping' five different people both here and at other forums with their campaigns, setting, adventures, articles, and what-not. I normally have one or two such 'irons' in the 'fire', there's just a few more than usual at the moment.

I look for holes or gaps or anything else players may exploit, point out where things might be muddled, suggest patches, and generally act like both a sounding board while providing that all important differing POV. Simple stuff really.

My real life career is much the same. I'm a tech rep who doesn't walk in screaming "You're doing it WRONG!!!" but instead says "What don't you feel is right" and "Have you thought of this?"

I'm also more than willing to call a spade a spade. Many canonistas try to make every jot and tittle fit somehow. That's utterly futile in my book. After 25+ years, dozens of writers, several editors, different publishers, and everything else you finally must admit the Traveller and the OTU are not a seamless whole, were never a seamless whole, and were never meant to be a seamless whole. It just ain't happening, this isn't Empire of the Petal Throne after all.

Look at the 'Changing UWPs' thread for instance. They've got 33 MEGABYTES of UWP data they know is RUBBISH. They know is was generated incorectly, they know it doesn't match AotI, they know it doesn't match other published materials, they know it's pure crap. What are they doing with it? Tossing it all out and starting anew with AotI locations and a properly coded generation algorithm? Hell no! They're going to keep it all and make changes by hand!

Thirty three megabytes poured through various spreadsheat 'sieves' to catch mistakes which will then be corrected by hand. Good Sweet Strephon! They actually think it will work too... shakes head

I'm a confirmed pack rat, but I also know when to throw things out.

Anyway, great ideas keep, 'em coming.


Have fun,
Bill

 

[far-trader]

Just so long as you're not considering changing your style Bill

Aww, what am I saying, you wouldn't if you could and that's why I hit the clicker anytime I see your name, even in threads that might hold no interest for me. It's either educational, humorous, or both, usually in addition to a mess of other adjectives.

 

[Scott Martin]

I'm glad I wasn't actually drinking my drink when I hit Bill's "Good Sweet Strephon!" or it would have ended up on my screen. (a poor choice, since I'm currently on the notebook)

While I agree that poring over 33 MB of "questionable" data is a lot of work, I can certainly see an argument that it is *less* work than trying to get people to agree to use a "new" set. Volunteers tend to set their own priorities, so here's hoping that we get some good stuff out of the effort. If not, hopefully folks not involved with the project won't say "I told you so" too loudly

____________________________________

Anyway, for the "Back on topic" part of this thread, Most folks think that:

1) Jump is a gravitic phenomenon / related to gravitic technology

2) There is some mechanism that prevents jump "emergence" from happening on (through, whatever) another body in "normal" space whether this is a variant of jump masking or just "pushes" small stuff out of the way

3) There is a distinct, detectable high energy event on jump emergence

4) The fuel used for Jump is supplied at jump initiation.

5) A gravity field (or something) will cause a jumping starship "intersecting" a 100D limit to leave jumpspace. (presumably a week after jumping)

6) The power used for jump initiation does not need to be sustained throughout the jump
______________________________________

So: questions for the class:

0) Are the above points a majority agreement, or have I missed (or misread) any of these?

1) Is there a (detectable, distinctive) high energy event on jump initiation?

2) Can the origin / target of jump be determined by observing these events?

2a) Can the direction of jump be discerned from jump exit / emergence?

2b) Can the distance of jump be discerned from jump exit / emergence?

3) Does use of a jump grid change the signal / energy event from jump / emergence?

4) How much power needs to be sustained through jump?

5) Is some "normal space" vector conserved through jump, or does the jump field act as a sump / sink / enhancer or have some hard limit on emergence velocity (relative to the star, the galaxy, fixed frame of reference "X")

My Answers would be:
1) Yes (Power and/or gravitic signature should be very distinctive)
2) No
2a) No
2b) Yes (based on power output and signature)
3) Yes ("smooths" the gravitic disturbance on exit / entry)
4) None or next to none
5) I don't know, but I'm starting to favor jump acting as a velocity sink so that emergence is always at some random low velocity (less than a kilometer per second relative to the local star) This conveniently kills off most of the "Jumping C-Fractional Rock" tactics, and explains why no-one thought to use them in Canon. (like say Lucan...)

IMO you can figure out how far a ship is going (based on its power output and entry / exit characteristics) but you can't determine its direction, since that "vector" isn't through normal space.

But I am extremely interested in other peoples comments on the above.

Scott Martin

 

[Scott Martin]

Ptah:

Your "Jump Flash" mechanism would result in truly unholy amounts of energy from "incedental" particles, and you'd have trouble rationalizing why the ship itself wouldn't radiate in a similar way

Or are you postulating that this only happens to particles on the "interface" between J-space and normal space? If this is the case, then releasing the "jump hydrogen" early would have a high probability of killing the crew and all aboard due to radiation, with the interface running across a high particle density. (unless the field is initially set up a LONG way from the ship: too many variables for me to think about right now...)

This would nicely explain why jump within 1 Diameter = "Boom" since most planets have an atmosphere...

Scott Martin

 

[Whipsnade]

Originally posted by Scott Martin:
[QB]While I agree that poring over 33 MB of "questionable" data is a lot of work...

Scott,

It's not 'questionable, it's crap.

On to your list o' questions:

1) Is there a (detectable, distinctive) high energy event on jump initiation?

OTU - It's debatable. Not mentioned until TNE and then with many, many, many qualifiers. You know someone has jumped. How far away you know that is not said. What else you know... depends. It is mentioned that you can 'sometimes' develop enough info to learn the destination.

MTU - Pretty much the OTU line without the chance of guessing destination from the 'signal'. Destination can be sometimes inferred by others means; known drive rating, real space vector, potential masks, etc.

2) Can the origin / target of jump be determined by observing these events?

OTU - See above.

MTU - See above.

2a) Can the direction of jump be discerned from jump exit / emergence?

OTU - I've never read that to be suggested in any Traveller product in any version. Could have easily overlooked it.

MTU - No. Same inferences can be made as in #1.

2b) Can the distance of jump be discerned from jump exit / emergence?

OTU - See above. (Possible inferences? Maybe?)

MTU - See above.

3) Does use of a jump grid change the signal / energy event from jump / emergence?

OTU - Unknown.

MTU - Not applicable.

4) How much power needs to be sustained through jump?

OTU - I believe that Traveller has it both ways. There's the story about the IN destroyer that had the equivalent of 250K years pass in jump sapce. No power source could last that long. However, there's other mentions of ships being lost when power is lost.

MTU - A relatively small amount of power; when compared to weapons or drives, is needed to control 'interface tension'.

5) Is some "normal space" vector conserved through jump...

OTU - Definitely yes. Several examples throughout every version; CT JTAS 'Jumpspace' article, MT adventures, TNE color sidebars, etc.

MTU - Yes. (I'm well aware of the 'universal frame of reference' problems this brgins up. Vectors carried through jump are one of the big ways to infer jump destination/origin.)


Have fun,
Bill

 

[mike wightman]

Originally posted by Scott Martin:
Sigg:
FF&S (1) page 42 requires surface area for jump drives (1 square meter per 3 cubic meters of volume) Presumably this is for a jump grid, so TNE *does* require a jump grid.

Yep,
I've seen that surface area requirement.
But no mention of a jump grid.

In most CT deckplans the jump drive is shown with something sticking out of the back of the ship. That would require surface area too

T4's FF&S states that the jump drive requires a lanthanum hull grid (0.5% x [2+Jn]) x ship's total surface area.

The surface are of the FF&S is related to the jump machinery itself - this suggests to me it's the stuff sticking out the back

 

[TheEngineer]

Q: 1) Is there a (detectable, distinctive) high energy event on jump initiation?
A:
Considering the MT ruleset a jump drive contains a "high yield" powerplant, which could be a reason for a significant neutrino emission increase.
OTOH suddenly disappearing mass would be perfect for creating gravitational waves, which might be detectable by a densiometer (?).
And as I work without a jump bubble in MTU there is a vast amount of jump drive fusion waste products around the exit point, which is quite easily detectable.
So, I would say jump initiation is detectable, too.

Q: 2) Can the origin / target of jump be determined by observing these events?
A:
Well, it might be possible to combine results from analyzing the magnitude of the above emissions with potential jump masking effects of the actual system and possible destination systems to get at least a hint on a possible "real" destination.
But a fleeing ship could lie, e.g. by giving higher signitures than actually used, or by "running loaded" with pre-charged capacitors.

Q: 2a) Can the direction of jump be discerned from jump exit / emergence?
A:
Perhaps only some hints resulting from analysation of masking effects and possible jump paths and of course the normal flight vector. But surely no safe information here.

Q: 2b) Can the distance of jump be discerned from jump exit / emergence?
A:
Just like 2a, but perhaps there might be a slight chance, if a jump bubble concept is used. Here there should be a relationship between jump bubble remaints and the arrived ship displacement tonnage. So active sensors could be used to calculate the amount of jump bubble fuel used and thus calculate back the jump distance.
Without the jump bubble thing I see no chance, except again possible hints thru jump masking effects..

Q: 3) Does use of a jump grid change the signal / energy event from jump / emergence?
A:
Maybe a jump grid is more cinematic

.
Generally I do not consider any further advantages/disadvantages.

Q: 4) How much power needs to be sustained through jump?
A:
I dont know anything OTU related on this one. Anyway in MT there are jump capacitors, which might be used to provide precalculated and failsafe power patterns even in jump.
IMTU I estimated jump capacitors to hold e.g. 14000 GJ for a 100t jump-2 ship and consider about 90 % to be used for jump initiation and the rest for field stabilisation (so in the example just 1 MW left for jump field modulation).

Q: 5) Is some "normal space" vector conserved through jump, or does the jump field act as a sump / sink / enhancer or have some hard limit on emergence velocity (relative to the star, the galaxy, fixed frame of reference "X")
A:
Just yes. Guess the retained vector is really a substancial Traveller thing

Regards,

Mert

 

[Scott Martin]

Sigg

The volume requirement is linear with volume: that suggests it is not "stuff sticking out the back" or it would follow the cube square law (volume increases as the cube of raduis, surface area increases as the square)

And using Traveller deck plans to infer *anything* is generally counter-productive (I infer that the crew on free traders are really, really tall, or like a lot of bed space to roll around on...)

Scott Martin

 

[Ptah]

Originally posted by Scott Martin:
Ptah:

Your "Jump Flash" mechanism would result in truly unholy amounts of energy from "incedental" particles, and you'd have trouble rationalizing why the ship itself wouldn't radiate in a similar way

Or are you postulating that this only happens to particles on the "interface" between J-space and normal space? If this is the case, then releasing the "jump hydrogen" early would have a high probability of killing the crew and all aboard due to radiation, with the interface running across a high particle density. (unless the field is initially set up a LONG way from the ship: too many variables for me to think about right now...)

This would nicely explain why jump within 1 Diameter = "Boom" since most planets have an atmosphere...

Scott Martin

Hi Scott,
By the way nice set of questions for focus above, will try to get to them later.

Actually IMTU theory hydrogen is not released from the ship. So the particle density is that of space. In my theory the only particles that will be accelerated in normal space are those with equal probabilities of being both inside and outside the jump space. Based on intuition (well excessive experience with quantum mechanics )I'm estimating this will be a very small number of particles as the "thickness" of this shell would be on the order of the Planck scale. That is, it is one dimensional on this scale and only those particles exactly on the edge of the shell get accelerated to the speed of light.

I like your idea on emerging into a planet/atmosphere equals boom. IMTU too much mass to push out of the way means you don't emerge there (dying by more of a wimper in jump space), of course you may emerge nearby, with my jump point shifting concept.
What happens to the mass within the sphere? It turns into energy. With MTU limits on what you can emerge into this is energy is very small.

For example, the number density of interplanetary space near Earth is about 5 atoms/cm^3 which are mostly H. For 10 H atoms per cm^3, that is about 2x10^-17 g/m^3 of H or about 0.002 J of energy per m^3 (by E=mc^2). These are very small amounts of energy. It gives one an idea of how empty space really is, even in the "dusty" regions around stars.

Of course if one emerged into 1 atm (about 3x10^17 atoms/cm^3, mostly N2) this becomes 1.25x10^15 J/m^3, boom!. Hence, one reason IMTU theory one cannot emerge into a mass density that is too high.

I'll repeat the caveat that my jump theoy is not canon and never was intended to be or explain variations in canon.

 

[Ptah]

Originally posted by Scott Martin:


1) Is there a (detectable, distinctive) high energy event on jump initiation?

IMTU Yes, but the major signal requires good gravity-wave/graviton sensors to detect, so not necessarily high energy or auto-detection. Thus, IMTU there is competition between sensor technology and stealthy jump entry (based on ship size, navigation skill, and classified technology).

2) Can the origin / target of jump be determined by observing these events?

IMTU Yes, but it is a non-trivial task.

.
2a) Can the direction of jump be discerned from jump exit / emergence?

IMTU Yes, but it is a non-trivial task.

2b) Can the distance of jump be discerned from jump exit / emergence?

IMTU Yes, but it is a non-trivial task and is convoluted with ship size information.

3) Does use of a jump grid change the signal / energy event from jump / emergence?

IMTU, Yes, it helps decrease the signature by allowing finer control over the jump field and matching conditions with local or jump space. It also reduces the chance of misjump.

4) How much power needs to be sustained through jump?

IMTU, roughly 45% of fuel is used to enter jump space, 45% to emerge, and 10% to maintain the jump field in jump space. In extremis, the jump field can be weakened in jump space to decrease fuel requirements, at the danger of misjump and experiencing jump sickness.

5) Is some "normal space" vector conserved through jump, or does the jump field act as a sump / sink / enhancer or have some hard limit on emergence velocity (relative to the star, the galaxy, fixed frame of reference "X")

IMTU, Yes, relative to the center of gravity of the local system (the star if not a binary etc. system). In theory IMTU, there is no limit on what this vector can be, but in practice high velocity vectors increase the chance of misjump. IMTU one can decrease the speed of the ultimate emergence vector in jump space at the exspense of using more fuel.

Someday I will take into the account the differences in overal energy, e.g. different points in the system potential energy well and rotational velocity w.r.t. the center of the galaxy. Having this, I would say IMTU the emergence vector rotates to compensate for the energy differences and to the extent this cannot compensate fuel is consumed to use the jump field to make up the energy difference (that is if I need to sink 1J I might require 100J or more worth of fuel is used). IMTU you never emerge with greater velocity than you netered jump space.

 

[Whipsnade]

Originally posted by TheEngineer:
Considering the MT ruleset a jump drive contains a "high yield" powerplant, which could be a reason for a significant neutrino emission increase.

TheEnginerr,

That's a very good point. We start to stumble due to the various Traveller editions though, just like grids and fuel requirements.

CT had no neutrino detectors. Hell, CT hardly had anything in the way of specific detectors or sensors.

So, MT introduces neutrino detectors only to have TNE scales them back big time. IIRC, there's even a TNE design note or Q&A on that very topic, something about examining the idea of a neutrino detector with a guy who actually runs a neutrino detector.

T4 didn't mention them, unless they're buried in FF&S2 somewhere. GT doesn't mention neutrino detectors specifically and has anyone seen them in T20?

So they're mentioned in one version, dismissed in another, and ignored in four more. Ugh. Take your pick then.


Have fun,
Bill

 

[TheEngineer]

Traveller is just so, errr, "flexible"

Well, in T20 there are neutrino sensors for vehicles, but there seem to be no explicitly noted ones for starships....

 

[Whipsnade]

Originally posted by TheEngineer:
Traveller is just so, errr, "flexible"

TheEngineer,

LOL! What a beautiful way to put it!

I suppose the 'answer' will depend on the old OUT-IMTU-IYTU fallback. If you decide YTU has neutrino sensors you'll be able to detect all sorts of things regarding jump and plenty of other things beside.


Have fun,
Bill

 

[Fritz_Brown]

Bill, I really like your variation on J-drives. (I had read and captured the "How Jump Works 201" pages, and liked them, too.) Either way works for MTU, though the official explanation will now incorporate Bill's ideas.

IMTU:
1) Yes, though it is not readily detectable at the same range as jump emergence.
Jump emergence can be detected out to Oort cloud ranges (from say, Earth's orbit), but your sensor has to be aligned fairly closely to see it. A good sensor net can help with this.
2) The origin/target can be guessed within certain limits based on analisys of the signature. See 2a/b.
2a) Because of the design of jump engines, you can't enter/exit j-space sideways/backwards/upside down/etc. And, you can't be moving at a vector other than toward your destination (in n-space). So, analysis will tell you the "shape" of the bubble and (hence) direction.
2b) No, though you can guess based on analisys of the vector and knowing what's out there. (For example, if he's aimed down the main, then a J-2 might be tricky based on masking, etc. So, you would assume a J-1.)
3) I think I will drop the grid thing....
4) Very little of the j-drive fuel is used during jump. Very little.
5) Velocity is carried through, but it increases your likelihood of hitting something unfortunate, and it increases your energy signature on emergence.

One different tech IMTU is the microjump drive. There are phenomenon in the universe where you get a different result (not the expected nothing) if you apply a much lower energy to the mechanism. So, scientists in a particular pocket empire were experimenting with j-drives with very low energy inputs. They discovered that you could shorten the amount of time in j-space AND the distance traveled in n-space (and, with a special configuration of j-drive, natch). In effect, you were popping into a fractional j-space. The power applied is approximately 15% of normal for the initial jump, then the emergence energy is captured and cycled back for the next jump. However, you actually use approximately 70% of your (normal) fuel for the initial jump - then a small fraction to re-initiate the "bubble" each time you go in.
So, you power up and jump (about J0.05), emerging about 57 light days out in about 6.6 hours. Then you spend an hour cycling the emergence energy and do it again. (BTW, you can make small turns - about 18* - between each jump, enabling you to jump in a circle back to your point of origin.) After 30 microjumps (about J1.5), you must bleed-off the capacitors and start from scratch (70% fuel, etc.).
You cannot get above the one level of efficiency with this. IOW, you will move at an equivalent of J1 (distance/time). If you want the speed of J2, you better install J2 engines.

Bigest advantages are 1) circling back, 2) circuituous routes to hide your destination/origin. Jump entry/emergence signatures are similar to J1.

 

[Scott Martin]

I guess that I should have mentioned that if your answer to #2 (Can the origin / target of jump be determined by observing these events?) is "Yes" then by definition the answer to 2a (Can the direction of jump be discerned from jump exit / emergence?) and 2b (Can the distance of jump be discerned from jump exit / emergence?) will be "yes" as well...


Scott Martin

 

[Whipsnade]

Originally posted by Fritz88:
Bill, I really like your variation on J-drives. (I had read and captured the "How Jump Works 201" pages, and liked them, too.) Either way works for MTU, though the official explanation will now incorporate Bill's ideas.

Fritz88,

If they're of any help to you and your group I'm glad to have helped. Fold, spindle, and mutilate to your heart's content.

Like I wrote, the explanation suited our needs in 1982-83. Whether it works for anyone else depends on their needs. I worked up the explanation for that long ago group and then rarely used it if at all for the next 15 years of GMing!

The rest of your post is rather interesting. I'll have to mull it over some...


Have fun,
Bill