Playability of STL Only Interstellar travel in GURPS?

[Fred Brackin]

Originally Posted by malloyd

The classic dodge with a wormhole system is to have somebody else build it a long time ago.

In one scheme I worked on the termini of the wormholes weren't even in the same universes (probably). Going to different places than photons do you don't get relativity problems.

[sir_pudding]

Originally Posted by Fred Brackin

On the other hand, I haven't seen much sign of it's development in the real world.

You haven't? There's quite a lot of AI development, and some futurist or another is always predicting a breakthrough in mere decades.

I suppose this is turning into one of those hard AI/soft AI arguments, but I don't see anything inherently implausible about AI.

At any rate it's certainly more plausible than wormholes (which require Jovian sized amounts of negative mass to open; and possibly can't be safely navigated even if they do exist).

EDIT: Even if your comparisons to GURPS complexity are apt, isn't complexity meant to be a logarithmic scale of overall computing power?

[Ze'Manel Cunha]

Originally Posted by malloyd

No, you fire it back along the ship's *normal* space track. Since it can't travel FTL with respect to Vega, and 6 months after it left Terra from the standpoint of Vega it had not arrived there yet, when you get there via the second wormhole, the first one doesn't exist yet. Yes it makes no sense. That's the point. FTL travel in a relativistic universe is equivalent to time travel, and inherently causes paradoxes like this.

No, you're trying to create a false paradox, it's a common game to play but it doesn't work relatively speaking at all, there is no time travel, the relativistic universe isn't perturbed by that game.

From what you said earlier, you travel STL to Vega.
Vega is 27 light years away from Terra and you're traveling at 99.995% of C.

If you leave Terra on Jan 1, 2050 you arrive at Vega a bit more than 27 years after you left Terra on Jan 1, 2077, the people on Terra have experienced 27 years while you have experienced about 99 days in transit.

You open a wormhole between Terra and Vega on Jan 1, 2077.
The fact that your frame of reference and clock says it's April 10, 2050 is not a paradox, that's simply the normal relativistic effect, when you step from Vega onto Terra you arrive on Jan 1, 2077, not on April 10, 2050. That's basic relativity 301, no paradoxes there.


You then say 6 months after you opened the wormhole and returned to Terra you go back to launch your missile. If the wormhole travel is instantaneous you arrive on Vega on Jun 1, 2077, if it takes you 6 months of travel time at 99.995% C relative time in the wormhole from Terra to Vega then you arrive on Vega on Dec 1, 2077, though your internal ship's clock says that it's still Jun 3, 2077.

It doesn't matter what your ship's time is though, if you arrived on Vega on Jun 1, 2077 and launched a missile back to Terra "along the ship's *normal* space track", then the missile arrives on earth a bit more than 27 years later, on Jun 1, 2104.
If you arrived on Vega on Dec 1, 2077 and launched a missile back to Terra "along the ship's *normal* space track", then the missile arrives on earth a bit more than 27 years later, on Dec 1, 2104.

[sir_pudding]

Originally Posted by Ze'Manel Cunha

No, you're trying to create a false paradox, it's a common game to play but it doesn't work relatively speaking at all, there is no time travel, the relativistic universe isn't perturbed by that game.

I've had this same trouble ever since Kip Thorne proposed this. The problem I have with thinking that way you do is Dr Thorne is highly respected physicist and most of his field accepted the paper at face value. I am not a physicist, so I suspect that I must be missing something here.

[Ze'Manel Cunha]

Originally Posted by sir_pudding

I've had this same trouble ever since Kip Thorne proposed this. The problem I have with thinking that way you do is Dr Thorne is highly respected physicist and most of his field accepted the paper at face value. I am not a physicist, so I suspect that I must be missing something here.

Thorne has clearly stated that in all his calculations no paradoxes are engendered by passing through traversable wormholes.

To get paradoxes in wormhole travel you need to presuppose quantum fields creating time curves allowing time travel, which doesn't work relativistically speaking, and as far as I know it's something Thorne went on to disprove in his research.

Now people toss out lots of fantasy suggestions on how quantum mechanics can break relativity, but if we stick to a relativistic universe there's no paradox at all when using wormholes.

[sir_pudding]

Originally Posted by Ze'Manel Cunha

Thorne has clearly stated that in all his calculations no paradoxes are engendered by passing through traversable wormholes.

He does say they can be used as "time machines" and the cited paper was one that discusses this. Isn't that what we are talking about?

[Fred Brackin]

Originally Posted by sir_pudding

You haven't? There's quite a lot of AI development, and some futurist or another is always predicting a breakthrough in mere decades.

I suppose this is turning into one of those hard AI/soft AI arguments, but I don't see anything inherently implausible about AI.

I said it didn't break conservation laws.

However, in terms of something even vaguely like human ability to interact with the real world? No, I don't see many signs of that at all. The futurists who are forever predicting it just around the corner are goofy.

Take the "prediction" in 2001:A Space Odyssey of the HAL 9000 just 30 years in the future. That turned out to be grossly wrong bit it didn't look silly then. I doubt that the predictors of Human-like (but superior in some ways) AI just 30 years from _now_ are going to be any more accurate.

AI is always 30 years in the future like flying cars and fusion power and I've been through too many iterations of this not to be cynical.

[sir_pudding]

Originally Posted by Fred Brackin

AI is always 30 years in the future like flying cars and fusion power and I've been through too many iterations of this not to be cynical.

But you instead think that artificial negative energy, negative mass, and traversable wormholes are plausible?

[malloyd]

Originally Posted by Ze'Manel Cunha

No, you're trying to create a false paradox, it's a common game to play but it doesn't work relatively speaking at all, there is no time travel, the relativistic universe isn't perturbed by that game.

From what you said earlier, you travel STL to Vega.
Vega is 27 light years away from Terra and you're traveling at 99.995% of C.

If you leave Terra on Jan 1, 2050 you arrive at Vega a bit more than 27 years after you left Terra on Jan 1, 2077, the people on Terra have experienced 27 years while you have experienced about 99 days in transit.

You open a wormhole between Terra and Vega on Jan 1, 2077.
The fact that your frame of reference and clock says it's April 10, 2050 is not a paradox, that's simply the normal relativistic effect, when you step from Vega onto Terra you arrive on Jan 1, 2077, not on April 10, 2050. That's basic relativity 301, no paradoxes there.

But at that point you've violated the assumption of the system that supposedly preventing the trip from taking 27 years from the point of view of Terra for the ship crew. If they step home through the wormhole, they've been gone 27 years.

In this interpretation, if they've had the wormholes open aboard there ship as they travelled each direction, then instead of the two ends being the same age and hence travelling through the second wormhole allowing them to arrive at Vega before the first, one end of the first wormhole it is now 26.6 years older than the other, and in order to generate the paradox they need to acquire another Terra to Vega wormhole that has a different time difference between the two ends of it - so they travel home slightly more quickly with the second one (or alternately, have travelled more slowly placing the first), generating a hole that has the Vega end say 26.7 years older than the Terra end. Now in 2126.7 they step through it on Terra, arrive at Vega 26.7 years earlier in 2100.0, back through the first wormhole, arrive at Terra 26.6 years later in 2099.9 and go hit themselves over the head so they don't step through the first wormhole. This is actually the more traditional interpretation, but it's not the one asserted to have been set up in the original problem statement.

[Ze'Manel Cunha]

Originally Posted by sir_pudding

He does say they can be used as "time machines" and the cited paper was one that discusses this. Isn't that what we are talking about?

He has more recently said that they can't be used as "time machines" after repeated calculations.

Originally Posted by malloyd

But at that point you've violated the assumption of the system that supposedly preventing the trip from taking 27 years from the point of view of Terra for the ship crew. If they step home through the wormhole, they've been gone 27 years.

What assumption?

Relativity says the crew experiences 99 days instead of 27 years, but it still takes them 27 years to make the trip.

That's just standard relativity, like what I learned in school 20 years ago, it hasn't changed and people like Thorne have continually done experiments which maintain relativity.