Baseline OTU

[rancke]

If jump drive's temporal uncertainty is held to be true, and every version of Traveller has included it, and if, as you correctly point out, planets and stars move, then how can you plot a "hit" on the 100D limit? There may situations when that can occur, but it cannot happen regularly.

A planetary jump limit is a BIG target. As I suggest above, it can happen regularly. However, you can't predict WHERE along the 100 diameter limit you'll arrive.

Some have suggested that jump drive somehow adjusts for the temporal uncertainty, readjusts a plotted exit point, and thus deposits the ship at the 100D limit.

I've dropped that idea, Bill.

P.S. Hans' post above this one is another reason why worrying about hitting the jump limit is not such a big deal.

Oh, you saw it.


Hans

 

[Hemdian]

[Some have suggested that jump drive somehow adjusts for the temporal uncertainty, readjusts a plotted exit point, and thus deposits the ship at the 100D limit. Aside from the issue of jump drive somehow being "sentient" or aiming near-c rocks through jump space, I find that proposal hard to believe.

It depends on reference frames. If the exit point is relative to the start point (which for normal travel would be the case) then temporal uncertainty would be a problem because, as already stated, planets and stars are moving. However, with jump drive you leave spacetime at your start point and re-enter it at the exit point. So it is entirely rational to suggest that the start and end points are not relative to each other: the end point could be relative to a target mass. Thus if the target mass has moved relative to the start point this is of no consequence.

 

[rancke]

It depends on reference frames. If the exit point is relative to the start point (which for normal travel would be the case) then temporal uncertainty would be a problem because, as already stated, planets and stars are moving. However, with jump drive you leave spacetime at your start point and re-enter it at the exit point. So it is entirely rational to suggest that the start and end points are not relative to each other: the end point could be relative to a target mass. Thus if the target mass has moved relative to the start point this is of no consequence.

I agree. Bill and I had a long argument about that. But Occam's Razor says go with the simpler solution, and after I realized that if a target is big enough and all you care about is hitting is SOMEWHERE, no matter exactly where, it dosen't really matter that it's a moving target, I decided to go with the simpler explanation.


Hans

 

[Whipsnade]

So it is entirely rational to suggest that the start and end points are not relative to each other: the end point could be relative to a target mass. Thus if the target mass has moved relative to the start point this is of no consequence.

Hemdian,

GT:ISW aside, "target mass" has never been a part of jump in the OTU. Never as in never, never as in not mentioned at all in Mr. Miller's JTAS essay, never as in never necessary until GT:ISW felt the need to "explain" the warplines on a wargame map that predates Traveller.


Regards,
Bill

 

[Whipsnade]

Bill, have I ever asked you or seen your explanation of this in context to the above? I'm drawing a blank but it could be I've just forgotten it.

Dan,

It's a logical inference from Mr. Miller's JTAS jump space essay.

Let me explain. When GT:FT came out and explicitly presented the concept of jump masks and shadows, I happened to be enjoying the company of a graduate student at Brown. She was newly returned to school, involved in biochem research, and taught logic to incoming freshman. Even better, she wasn't scared off by wargaming or RPGs because she saw them as logic puzzles and was rather kind to gray-headed fat men.

Anyway...

I sat her down with the JTAS essay, GT:FT, plus a few other sources and essentially said Apply Occam's Razor with a vigor, Professor, and tell me how all this works with the least amount of assumptions.

It was she who pointed out the ramifications of the canonical temporal uncertainty to me and I used a great part of what she told me when I wrote my Lines and Limits, Masks and Shadows essay for the TML.

It's the simplest solution, the one that adds the least to all the canonical descriptions. Yes, I know there are hundreds of mentions in canon about "hitting" the jump limit or "exiting" at the jump limit. As Hans points out that is still true, it just that it no longer happens all the time. If you want it happen all the time, you need to add something to our 30+ year understanding of jump drive. You've got to create a "work around" regarding temporal uncertainty.

As I pointed out, because you don't know the "when", you can't calculate the "where". In order to calculate "where", the "when" has to be becomes known. Canon never explicitly states says when you learn the "when", but it very strongly implies that you learn the "when" after you initiate jump and are no longer in real space. After all, ships do not squirt a final broadcast while entering jump announcing how long their jump is going to last, despite that being a rather vital piece of information.

So, because the "when" isn't know until after a jump begins, any use of that "when" to calculate your "where" must occur after you begin your jump. That directly contradicts canonical descriptions of what navigators do, when they do it, how jump tapes work, and whether a`ship can maneuver in jump space among many other things.

Because canon strongly implies that humans can't use the post jump initiating "when" to calculate the "where", that leave the jump drive itself to do the job. Hence my comments earlier about "sentient" jump drives. The drive would somehow replot the ship's exit point after a jump's time duration is determined and navigators would never comment on the adjustment.

Tell me, do you want to add sentient jump drives to canon just so that you can hit the 100D limit all the time?

For me, temporal uncertainty falls into the same category as jump masks and shadows. It's a part of the setting that I, as the GM, can apply whenever it suits me. Sometimes temporal uncertainty has a role, sometimes it doesn't, and my players only need concern themselves of it when I tell them too.

Hope all this bumf explains my position on the matter. I truly believe it is the simplest and most canonical description of issue and I believe that because someone far smarter than I who has no canonical axes to grind told me so!


Regards,
Bill