Everything I know about Jump I learned from MWM

[mike wightman]

Jump masking doesn't exist, MWMs article has 3 sentences about precipitation from jump, 2 of them make jump masking moot - it doesn't exist - while the third is the vague one that was interpreted by GT authors to give us jump masking.

It is mentioned in the article that a ship in jump is removed from our universe and the jump universe is not affected by anything in ours apart from when you are actively trying to get in or out.

 

[rancke]

Jump masking doesn't exist, MWMs article has 3 sentences about precipitation from jump, 2 of them make jump masking moot - it doesn't exist - while the third is the vague one that was interpreted by GT authors to give us jump masking.

Actually, jump masking is something Marc Miller told Chris Thrash existed when Chris asked him about how to interpret that old article.

It is mentioned in the article that a ship in jump is removed from our universe and the jump universe is not affected by anything in ours apart from when you are actively trying to get in or out.

That's certainly how I interpreted the article and the various CT and MT rules concerning jumps[*]. Until Marc Miller stated that he'd always meant jump masking to be implied. Personally, I wonder if he didn't just change his mind at some point, but that's really moot. Either he meant it all along or he DID change his mind. Bottom line is that jump masking exists NOW and has existed at least as far back as GT. Unless you're abandoning the OTU, it really doesn't matter if jump masking existed 30 years ago.

[*] Mind you, jump shadowing is most definitely a logical inference, yet there is not the slightest allusion to it in any of the rules, so the absence of jump masking in the rules isn't as conclusive as one might like to think.​

Hans

 

[fusor]

Well, since T5 presumably reflects Marc Miller's current views on Jump, what does THAT have to say about jump masking/shadowing?

If that clearly says that it exists, then I guess that the people who feel that they are bound by what Marc says will just have to accept it.

 

[BytePro]

Decades ago, I enjoyed populating MTU with exotic stellar objects - and one of my favorites were black holes.

The nice thing about the 100D limit (vs. a mass based limit) is the possibility a ship can jump even within the event horizon of a black hole...

(More OT - assuming all the mass is in the 'singularity' of a black hole, one needn't worry about galactic jump masking even on a core expedition )

 

[Rover]

Decades ago, I enjoyed populating MTU with exotic stellar objects - and one of my favorites were black holes.

The nice thing about the 100D limit (vs. a mass based limit) is the possibility a ship can jump even within the event horizon of a black hole...

(More OT - assuming all the mass is in the 'singularity' of a black hole, one needn't worry about galactic jump masking even on a core expedition )

Wouldn't the event horizon be considered the diameter of the black hold since we have no way of telling what happns befony it?

R

 

[fusor]

If the event horizon counts as the radius of the black hole, then a solar-mass BH's 100D limit would be about 300 km. Of course you'd be dead as soon as you arrive there anyway, pulled apart by tidal forces.

 

[Matt123]

The 100D limit is intended to represent the gravitational limits, the point gravity has an insignificant effect on jump.

I don't think you can apply the 100D limit quite so literally to a black hole .

Instead you need to figure out how far from the black hole do the gravitational effects fall to the same level as a planetary mass at 100D.

 

[BytePro]

Being unable to observe is not the same as being unable to predict

After all, black holes were predicted from theory, prior to any evidence being observed... however, the singularity nature probably is a mathematical artifact that is overcome in reality by effects not yet understood.

The event horizon does not represent an actual surface - just an event boundary... hence the name. It is not the 'diameter' of a black hole. As a 'singularity', that diameter is effectively zero and thus there would be no 100D limit - being beyond condensed matter, any actual diameter would likely be much smaller than the event horizon for any appreciable sized horizon. There are currently no accepted theories that cover the physical manifestation (as it were) represented by the mathematical singularities, so this is all pretty mute.

As to tidal forces... a ship can still accelerate against them (but not escape), though it would be best if it was of a type that was non-rotating. :devil:

Of course, the 100D limit probably had a gravity 'rationale' behind it (well, actually just a RP one) - but given the mechanic, jumping within an event horizon and back out can provide be a cinematic excuse for intentional time travel or extragalactic jumps, etc that still fits within the RAW. Just say'n.

 

[Rover]

This is pretty much a "how many angels can dance on the head of a pin" arguement. Personally I would consider the event horrizon to be the effective diameter of a black hole being that after you cross the horizon there is no return. you of course are free to differ.

But since the 100D limit is just an abstraction for game mechanics, wouldn't you have to be 100D away from the diameter of the star that became a black hole? The mass doesn't change and the gravitational force does not change. Replace the sun with a black hole of the same mass and all the planets will continue in the same orbits.

It would seem to me, if the 100d rule was supposed to be due to gravity, applying it to a black hole kinda goes against the spirit of the rule.

just my 0.02Cr

R

 

[dean]

Moot. Not mute. Just sayin'.

 

[fusor]

Back on topic....

I checked a friend's copy of T5 (from the playtest CD), and it does say, quite clearly, that "a ship automatically breaks out of jump space if its straight line course intersects a sphere 100 Diameters out from a gravity source larger than the ship". It even has its own section called "The 100D Rule".

So there you have it. Jump Masking/Shadowing is real, according to T5.

 

[BlackBat242]

So there you have it. Jump Masking/Shadowing is real, according to T5.

Yep... if you are playing T5 or a mix of T5 and other rules, then it exists.

The same with Marc's retro-fit of jump masking... if you are incorporating later rules and rule changes, then it exists.

If you are using CT rules, then any rules that come out from MT (1986) on are not valid... later clarifications are valid, but actual changes to try to make CT match later rule-sets are just that... a blending of CT and later version rules.

Marc may claim that he "always intended jump masking", but that's NOT what he wrote in the article... there he specifically said things that preclude jump masking. That makes his later statement a change in the actual rules.

He DID, in that article, establish jump shadowing... so that IS canon for CT.

 

[fusor]

Yep... if you are playing T5 or a mix of T5 and other rules, then it exists.

The same with Marc's retro-fit of jump masking... if you are incorporating later rules and rule changes, then it exists.

If you are using CT rules, then any rules that come out from MT (1986) on are not valid... later clarifications are valid, but actual changes to try to make CT match later rule-sets are just that... a blending of CT and later version rules.

Marc may claim that he "always intended jump masking", but that's NOT what he wrote in the article... there he specifically said things that preclude jump masking. That makes his later statement a change in the actual rules.

He DID, in that article, establish jump shadowing... so that IS canon for CT.

I guess nobody's forcing anyone to use that rule, but it's certainly crystal clear in T5. And some people here at least take the Word of Marc (whenever it's said) to be gospel. It has always struck me as peculiar that in pretty much everything else the new supersedes the old, but in Traveller it seems that the old trumps the new; even if it's written by the game's author whose views are otherwise held inviolate. It's really quite baffling. o:

The OTU must be a very confusing place though, given the random reality shifts that happen every few years. Sometimes ships get around by reactionless thrusters (MT), other times they get around using HEPLaR drives (TNE). Some worlds are ellipsoidal, but then they change to Thin/Low when you look at them differently (as described in MGT). And sometimes jump is blocked by 100D limits, and other times they're not. How strange!

This does indicate that Marc may be very much mistaken if he thinks that T5 is going to unify the Traveller community. Personally I think that it will just create more divisions, this time between the Orthodox CT Traditionalists and the Devotees of Marc's New Scriptures (I guess this is what you get for wrapping RPG material in religious terms such as "canon" )

 

[aramis]

The 100D limit is intended to represent the gravitational limits, the point gravity has an insignificant effect on jump.

I don't think you can apply the 100D limit quite so literally to a black hole .

Instead you need to figure out how far from the black hole do the gravitational effects fall to the same level as a planetary mass at 100D.

That's not a constant, either.

The gravitation at 100 diameters of a normal density size 8 world of 8000miles diameter is 0.001m/s^2
For a high density world, it may be as much as 0.002m/s^2, and low density down to 0.0005m/s^2.
But all three have the same shadow on jumpspace.

T5 does make it clear an item smaller than the jumping item in the jumping item's 100diameters is toast...

 

[McPerth]

Yep, but that answer also butchers the need for any ship to carry jump fuel. Just fit a BG and have a mate whack you with sufficient nukes to jump.

At TL15, you will get J6 jumps without the need for 60% fuel. Trade in the Imperium will be revolutionized...

And those nukes cost how much?

Also the BG itself is not common Imperial tech.

And before anyone says 'so just build a solar collector' are they just going to give the energy away for free?

Last time I looked my electricity bills were going up...

As it's true nukes are quite expensive, they can use energy weapons for that. But in truth, they don't even need that, as just aproaching the sun with your BG at 100% (quite more efficient than solar collectors, as they absorb all energy incoming) would fill your capacitors quite quickly (and when full, you turn off your BG and maneover to the desired jump vector).

 

[fusor]

That's not a constant, either.

The gravitation at 100 diameters of a normal density size 8 world of 8000miles diameter is 0.001m/s^2
For a high density world, it may be as much as 0.002m/s^2, and low density down to 0.0005m/s^2.
But all three have the same shadow on jumpspace.

If you're using gravity to define a pseudo-100D limit, then it's better to set the gravity to be constant (e.g. 0.001 m/s²). The jump shadow will vary in size depending on the planet's mass, but at least it'll feel like it makes some kind of physical sense.

In this example, an earthmass planet's limit would then be about 630,000 km, and a 1 solar-mass black hole's grav-100D limit would be exactly the same as for a 1 solar-mass star (thus removing any weirdness to do with event horizons), which would be about 2.4 AU.

Also, by definition the outside universe doesn't have any information about what happens inside the event horizon. That's the smallest radius that the outside universe 'sees', so it must be the radius used for 100D calculations.

 

[mike wightman]

As it's true nukes are quite expensive, they can use energy weapons for that. But in truth, they don't even need that, as just aproaching the sun with your BG at 100% (quite more efficient than solar collectors, as they absorb all energy incoming) would fill your capacitors quite quickly (and when full, you turn off your BG and maneover to the desired jump vector).

I don't have a problem with that.

Until BGs are installed routinely on merchants you aren't going to revolutionise merchant shipping in the Imperium.

Such things may well be doable at higher TLs, I doubt if the Imperium has fully explored the use of BGs in this way on it's limited supply of warships equipped with BGs.

Interesting idea for a TL16+ culture though...

 

[rancke]

Yep... if you are playing T5 or a mix of T5 and other rules, then it exists.

The rules really are the least important part of it. If you're playing in the OTU or an ATU that you want to keep close enough to the OTU to use the material others are going to produce in the future, then jump masking exists.

Marc may claim that he "always intended jump masking", but that's NOT what he wrote in the article... there he specifically said things that preclude jump masking. That makes his later statement a change in the actual rules.

Actually, it's unclear, subject to interpretation. That's why Chris asked Marc Miller about it in the first place.

He DID, in that article, establish jump shadowing... so that IS canon for CT.

And yet jump shadowing is not mentioned by one word anywhere in the CT rules.


Hans

 

[rancke]

I guess nobody's forcing anyone to use that rule, but it's certainly crystal clear in T5. And some people here at least take the Word of Marc (whenever it's said) to be gospel. It has always struck me as peculiar that in pretty much everything else the new supersedes the old, but in Traveller it seems that the old trumps the new; even if it's written by the game's author whose views are otherwise held inviolate. It's really quite baffling. o:

Not to me. To me it makes a difference if the new stuff is an improvement or not and whether it's a deliberate change or not. And also, I suppose, whether the change was really necessary.

If it works, don't change it.
If it doesn't work, change it for something that does.​

The OTU must be a very confusing place though, given the random reality shifts that happen every few years. Sometimes ships get around by reactionless thrusters (MT), other times they get around using HEPLaR drives (TNE). Some worlds are ellipsoidal, but then they change to Thin/Low when you look at them differently (as described in MGT). And sometimes jump is blocked by 100D limits, and other times they're not. How strange!

The nature of a retcon is that notionally things don't change; they've always been that way.


Hans

 

[fusor]

The nature of a retcon is that notionally things don't change; they've always been that way.

I guess Blackbat242 doesn't believe that.