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Noclevername
2018-Sep-30, 04:35 PM
OK, so here's the idlest question of the day (so far).

In the Star Trek universe, one pseudoscience explanation for Warp Speed (FTL) travel, is the existence of an alternate domain of spacetime called "subspace". This apparently acts as an absolute reference frame allowing simultaneity.

My question is, does it have to be an absolute reference frame? Can it merely be a broader "local" than the Einsteinian space we're used to, but still relative?

DaveC426913
2018-Sep-30, 04:48 PM
This apparently acts as an absolute reference frame allowing simultaneity.

How did you arrive at these two conclusions?

Noclevername
2018-Sep-30, 05:30 PM
How did you arrive at these two conclusions?

Because that's how it is described in the peripheral literature approved for official publication. Particularly the Star_Trek:_The_Next_Generation_Technical_Manual. (http://memory-alpha.wikia.com/wiki/Star_Trek:_The_Next_Generation_Technical_Manual)

Jens
2018-Sep-30, 11:03 PM
My question is, does it have to be an absolute reference frame? Can it merely be a broader "local" than the Einsteinian space we're used to, but still relative?

Sure, it could be just a broader local frame.



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Noclevername
2018-Sep-30, 11:33 PM
Sure, it could be just a broader local frame.



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Thank you.
That would explain (kinda) why warp travel outside the Galaxy is so much more difficult than inside it. At least that's how my mind makes sense of the often contradictory portrayals.

Noclevername
2018-Oct-04, 04:28 PM
OK follow up questions: What are some ways an FTL reference frame would affect causality?

How could it affect the local measurements of travel time? IE, could you have, say, an interstellar GPS? A regularly scheduled arrival time?

CJSF
2018-Oct-04, 04:41 PM
In Star Trek, there's an episode where proto-Q-being "Trelane" has been watching Earth through a telescope, so he sees humanity from hundreds of years earlier. The implications of this aren't really borne out in full in the episode, though.

For instance, say someone in the Federation sees the light/EM waves of a distant catastrophe, a planet-wide destruction. They send a starship at warp 9+ out there... and they arrive before the catastrophe happened, and might be able to stop it. I don't think anything like this is dealt with in Star Trek, is it? It doesn't have to just be catastrophes, of course. Even just "mundane" events like distant supernovae or gamma ray bursts. Just warp out there to watch their inceptions.

Are these they types of things you're asking about?

CJSF

Noclevername
2018-Oct-04, 04:56 PM
In Star Trek, there's an episode where proto-Q-being "Trelane" has been watching Earth through a telescope, so he sees humanity from hundreds of years earlier. The implications of this aren't really borne out in full in the episode, though.

For instance, say someone in the Federation sees the light/EM waves of a distant catastrophe, a planet-wide destruction. They send a starship at warp 9+ out there... and they arrive before the catastrophe happened, and might be able to stop it. I don't think anything like this is dealt with in Star Trek, is it? It doesn't have to just be catastrophes, of course. Even just "mundane" events like distant supernovae or gamma ray bursts. Just warp out there to watch their inceptions.

Are these they types of things you're asking about?

CJSF


That's backward time travel, they deal with that in many episodes and movies. Mainly by forbidding it, or showing it being misused.

I am not educated enough in physics to ask the right questions, I guess.

Noclevername
2018-Oct-04, 05:03 PM
Let's see if I can put it better:

In ST there's "subspace radio" signals, which never arrive before they are sent. They always take objective time to travel.

I guess there's a Light Cone of normal space, and a slightly wider Faster Than Light cone of subspace. Starships and signals slide in the areas between the 2 cones. Am I using that right?

Grey
2018-Oct-04, 07:53 PM
It's in principle possible for there to be some kind of absolute reference frame without causing any problems with our current understanding of physics (although, given the way relativity works, there would be no way to determine just what reference frame that was). However, any method by which you can communicate faster than light (which would include both travelling at warp speed and sending "instantaneous" messages via subspace channel) also means that you can send a signal backward in time, at least relative to some possible observers. Here (http://www.physicsmatt.com/blog/2016/8/25/why-ftl-implies-time-travel)'s a nice explanation of why that is.

Noclevername
2018-Oct-04, 10:12 PM
It's in principle possible for there to be some kind of absolute reference frame without causing any problems with our current understanding of physics (although, given the way relativity works, there would be no way to determine just what reference frame that was). However, any method by which you can communicate faster than light (which would include both travelling at warp speed and sending "instantaneous" messages via subspace channel) also means that you can send a signal backward in time, at least relative to some possible observers. Here (http://www.physicsmatt.com/blog/2016/8/25/why-ftl-implies-time-travel)'s a nice explanation of why that is.

If the FTL reference frame is not absolute, does that still apply? And if it is not back-time travel relative to the sender, or to an observer on the FTL ship, does it still "loop" that observer's timeline?

ADDED: Here's a (non-canon) POV on subspace's phictional physics and reference frame. http://www.physicsguy.com/subphys/SubspacePhysics.html#2

Noclevername
2018-Oct-04, 10:41 PM
Let me reword again:

Given the above, can an author come up with a plausible sounding physics excuse to prevent practical/personal timeline violations in "everyday" Warp travel usage? Beyond just saying "I'm the author, so there!"

Grey
2018-Oct-05, 01:36 AM
Given the above, can an author come up with a plausible sounding physics excuse to prevent practical/personal timeline violations in "everyday" Warp travel usage? Beyond just saying "I'm the author, so there!"The problem does still exist even if there is not an absolute reference frame, and there is no simple workaround. Simply put, if relativity is correct, then any kind of FTL travel or communication will allow signals to travel backward in time for some observers (and if you can send relativistic radio beacons around, you can make that happen for any observers you'd like). Conversely, if you want to have both FTL communication or travel, and also no violations of causality, then relativity has to be wrong. Of course, if you're writing fiction, you can just declare that relativity is wrong, and have done with it. ;)

Noclevername
2018-Oct-05, 01:44 AM
The problem does still exist even if there is not an absolute reference frame, and there is no simple workaround. Simply put, if relativity is correct, then any kind of FTL travel or communication will allow signals to travel backward in time for some observers (and if you can send relativistic radio beacons around, you can make that happen for any observers you'd like). Conversely, if you want to have both FTL communication or travel, and also no violations of causality, then relativity has to be wrong. Of course, if you're writing fiction, you can just declare that relativity is wrong, and have done with it. ;)

But as long as those observers are no in a position to do anything about it, does it matter if it is "technically" time travel?

AGN Fuel
2018-Oct-05, 02:30 AM
For instance, say someone in the Federation sees the light/EM waves of a distant catastrophe, a planet-wide destruction. They send a starship at warp 9+ out there... and they arrive before the catastrophe happened, and might be able to stop it. I don't think anything like this is dealt with in Star Trek, is it? [snip] Even just "mundane" events like distant supernovae or gamma ray bursts. Just warp out there to watch their inceptions.

Definite missed opportunity. Star Fleet could have waited to see a distant supernova, then have Wesley Crusher take a ship solo to the star at Warp 9 to observe the inception very, very locally.... maybe cross over to the Star Wars universe on the way and take JarJar on board as a "comic relief" crewman.

Noclevername
2018-Oct-05, 11:51 PM
But as long as those observers are no in a position to do anything about it, does it matter if it is "technically" time travel?

What I mean is, is there a way to have warp and not potential time paradoxes? So you have "time travel" that cannot actually affect events.

(NOT the Novikov principle.)

Solfe
2018-Oct-06, 02:10 AM
What I mean is, is there a way to have warp and not potential time paradoxes? So you have "time travel" that cannot actually affect events.

(NOT the Novikov principle.)

Have an AI on your computer tech that obscures paradoxes, or FTL creates a physical barrier to observing period. You don't have a paradox if you don't see them. Maybe your "rule" is that you can't have FTL if there is the potential for a visible paradox. It creates an odd situation where you characters can't use FTL while someone is looking with out that filter.

Alistair Reynolds has used this a couple of times. In House of Suns, the characters can't see the Andromeda Galaxy because someone went there using FTL. People in Andromeda can't see the Milky Way either. Kind of interesting. They are aware that both galaxies exist.

Noclevername
2018-Oct-06, 11:49 AM
Have an AI on your computer tech that obscures paradoxes, or FTL creates a physical barrier to observing period. You don't have a paradox if you don't see them. Maybe your "rule" is that you can't have FTL if there is the potential for a visible paradox. It creates an odd situation where you characters can't use FTL while someone is looking with out that filter.

Alistair Reynolds has used this a couple of times. In House of Suns, the characters can't see the Andromeda Galaxy because someone went there using FTL. People in Andromeda can't see the Milky Way either. Kind of interesting. They are aware that both galaxies exist.

So, all you have to do to blind an enemy warship, is go to warp in their line of sight? I can see a large power flying ships all over, to prevent anyone from detecting their actions...

Solfe
2018-Oct-06, 01:55 PM
So, all you have to do to blind an enemy warship, is go to warp in their line of sight? I can see a large power flying ships all over, to prevent anyone from detecting their actions...

I didn't think that through. I was thinking of the AI as being friendly and blinding you. An enemy ship is another matter. What is happening in the Reynolds story is no one has FTL, except for some very limited cases.

The one time he actually describes a ship in FTL during combat, one side cobbled together some stuff so they don't have the ability to observer anything strange. It appears to work until their opponents detect some gravitational effects. The enemy ship doesn't know what happened, only that everything was pulled towards the ship going at FTL speeds and then suddenly it stops doing that. It appears to me that if someone going FTL can conceptualized the problems of going to FTL, they get wiped from the timeline in the Reynolds universe.

Edit - It is hard to tell what Reynolds is saying, because the person who designed the FTL device should know that it will cause strange gravitational effects, but then puts that thought aside long enough to allow the ship to go faster than light. The moment the gravitation effect reaches the enemy, the FTL device stops working, the creator's best friend vanishes and the creator is killed. There is the implication that the creator's friend was on the ship until the moment the drive turned on and is retroactively erased from the timeline. Then the creator herself is kill/destroyed a little more slowly. Very weird.

In House of Suns, two friendly ships are going through a worm hole (or something) and the distortion prevents seeing each other and real time communication. At the end of the day, it turns out that not only don't have the ability to see the effect of FTL travel, the ship's computers are deliberately hiding facts to protect the crew from a variety of things.

cjameshuff
2018-Oct-06, 02:21 PM
I didn't think that through. I was thinking of the AI as being friendly and blinding you. An enemy ship is another matter. What is happening in the Reynolds story is no one has FTL, except for some very limited cases.

The one time he actually describes a ship in FTL during combat, one side cobbled together some stuff so they don't have the ability to observer anything strange. It appears to work until their opponents detect some gravitational effects. The enemy ship doesn't know what happened, only that everything was pulled towards the ship going at FTL speeds and then suddenly it stops doing that. It appears to me that if someone going FTL can conceptualized the problems of going to FTL, they get wiped from the timeline in the Reynolds universe.

Edit - It is hard to tell what Reynolds is saying, because the person who designed the FTL device should know that it will cause strange gravitational effects, but then puts that thought aside long enough to allow the ship to go faster than light. The moment the gravitation effect reaches the enemy, the FTL device stops working, the creator's best friend vanishes and the creator is killed. There is the implication that the creator's friend was on the ship until the moment the drive turned on and is retroactively erased from the timeline. Then the creator herself is kill/destroyed a little more slowly. Very weird.

In House of Suns, two friendly ships are going through a worm hole (or something) and the distortion prevents seeing each other and real time communication. At the end of the day, it turns out that not only don't have the ability to see the effect of FTL travel, the ship's computers are deliberately hiding facts to protect the crew from a variety of things.

This cure seems worse than the disease, since you're essentially erasing huge swathes of the universe from your reality every time you go FTL, and even handling that consistently seems improbable. You're better off if FTL just puts you in a different timeline.

Solfe
2018-Oct-06, 02:38 PM
This cure seems worse than the disease, since you're essentially erasing huge swathes of the universe from your reality every time you go FTL, and even handling that consistently seems improbable. You're better off if FTL just puts you in a different timeline.

Strangely, you'd think that he would put lots of characters out of play, but it doesn't happen.

I admit, the idea is bonkers. For 99% of his stories, he happily explains that c is the limit. Then he pulls out the math and says, "well, it's more like a guideline, you can go faster if only...". The characters don't have the inclination to do math or think about it deeply, so Reynolds gets a strange scenario to describe and the characters move really fast.

The interesting thing is, just as you say, the characters have limited access to other timelines. Apparently several of them and maybe another universe or two.

Grey
2018-Oct-06, 05:52 PM
What I mean is, is there a way to have warp and not potential time paradoxes? So you have "time travel" that cannot actually affect events.

(NOT the Novikov principle.)The only way is for relativity to be wrong. But again, for a fiction story where you have warp drive in the first place, there's nothing wrong with deciding that relativity is wrong. You can even decide that it's wrong the same way that Newton's laws of motion are wrong: that it's a very good approximation under most circumstances, but breaks down under certain extreme conditions (probably the circumstances under which it breaks down are exactly the thing that allows warp travel in the first place...). FTL travel probably isn't actually possible in our universe, so if you write a story that includes it, you're already adding new physics that likely doesn't exist. Just try to make the rules consistent enough that it isn't too jarring, and all will be well.

cjameshuff
2018-Oct-06, 08:51 PM
The only way is for relativity to be wrong. But again, for a fiction story where you have warp drive in the first place, there's nothing wrong with deciding that relativity is wrong. You can even decide that it's wrong the same way that Newton's laws of motion are wrong: that it's a very good approximation under most circumstances, but breaks down under certain extreme conditions (probably the circumstances under which it breaks down are exactly the thing that allows warp travel in the first place...). FTL travel probably isn't actually possible in our universe, so if you write a story that includes it, you're already adding new physics that likely doesn't exist. Just try to make the rules consistent enough that it isn't too jarring, and all will be well.

Well, there is the approach I mentioned, where FTL travel puts the traveler into a different universe. You could end up in a time and place equivalent to your past in that timeline and sabotage your alternate's FTL drive, but it's not your past you'd be interacting with. In the original timeline, you presumably just disappear, but that seems preferable to, say, having all photons originating from the Andromeda galaxy do the same mid-flight.

Roger E. Moore
2018-Oct-06, 09:04 PM
I could almost live without FTL drive as long as we could get FTL communication, like an ansible.

https://en.wikipedia.org/wiki/Ansible

Jens
2018-Oct-06, 11:17 PM
What I mean is, is there a way to have warp and not potential time paradoxes? So you have "time travel" that cannot actually affect events.

(NOT the Novikov principle.)

It seems to me that a fairly easy solution is to have a Newtonian universe where mass does not warp space and light just happens to travel at the speed it does. So time passes equally for all observers, and all you have done is found a faster way to get from A to B.


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DaveC426913
2018-Oct-07, 12:12 AM
It seems to me that a fairly easy solution is to have a Newtonian universe where mass does not warp space and light just happens to travel at the speed it does. So time passes equally for all observers, and all you have done is found a faster way to get from A to B.


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So, a sort of "Return to the Flash Gordon Era - where space is just space" answer. Not sure that would fly.

cjameshuff
2018-Oct-07, 01:20 AM
I could almost live without FTL drive as long as we could get FTL communication, like an ansible.

https://en.wikipedia.org/wiki/Ansible

Unfortunately the limitations have nothing to do with anything material passing from point A to point B, but arise from the transfer of information between those points.

Noclevername
2018-Oct-07, 02:32 AM
The only way is for relativity to be wrong. But again, for a fiction story where you have warp drive in the first place, there's nothing wrong with deciding that relativity is wrong. You can even decide that it's wrong the same way that Newton's laws of motion are wrong: that it's a very good approximation under most circumstances, but breaks down under certain extreme conditions (probably the circumstances under which it breaks down are exactly the thing that allows warp travel in the first place...). FTL travel probably isn't actually possible in our universe, so if you write a story that includes it, you're already adding new physics that likely doesn't exist. Just try to make the rules consistent enough that it isn't too jarring, and all will be well.

Well, the Star Trek solution is to have another domain of space that temporarily overlaps this one to enable Warp, in a way that does not normally happen in nature (unless the next writer decides it does). So I suppose that counts as extreme circumstances.

publiusr
2018-Oct-15, 10:06 PM
The "Janus" model seems all the rage these days:
https://forum.nasaspaceflight.com/index.php?topic=43501.0

Can't help you with Spore drive, other than saying it may have something to do with coupling to Voyager's fluidic space--likly home to the giant space protist from Immunity syndrome.

Dave241
2018-Oct-20, 01:17 AM
Thank you.
That would explain (kinda) why warp travel outside the Galaxy is so much more difficult than inside it. At least that's how my mind makes sense of the often contradictory portrayals.

I don't think that in Star Trek travel outside the galaxy is any different from inside it. The only reason they don't travel outside the galaxy is travel times. If I remember my Voyager correctly, they estimated it would take them 75 years to travel back home? Something like that. And that was about 2/3 of the galaxy. So if it takes 100 years to travel across the entire galaxy that would take 2,000 years to get to Andromeda. I think that alone is why they stay in the Milky Way, I don't believe there are any contradictory portrayals of this (maybe in the original series?.......).

CJSF
2018-Oct-20, 03:39 AM
I always thought it would have been fun for ST (or another franchise) to take the obvious ease of filming/less confusing for viewers convention of ships almost always approaching "right side up", like cars driving up to each other, and come up with a "Star Trek rationalization (as my brother and I used to call them)". Like, something about how the warp fields or artificial gravity worked with the orientation of the galaxy/SMBH or whatever. I mean, something totally bogus, but explanatory.

CJSF

Noclevername
2018-Oct-20, 05:23 AM
I don't think that in Star Trek travel outside the galaxy is any different from inside it. The only reason they don't travel outside the galaxy is travel times. If I remember my Voyager correctly, they estimated it would take them 75 years to travel back home? Something like that. And that was about 2/3 of the galaxy. So if it takes 100 years to travel across the entire galaxy that would take 2,000 years to get to Andromeda. I think that alone is why they stay in the Milky Way, I don't believe there are any contradictory portrayals of this (maybe in the original series?.......).

Travel outside the Milky Way has always been shown as a nontrivial problem of propulsion and navigation. See TOS "Where No Man Has Gone Before (http://memory-alpha.wikia.com/wiki/Where_No_Man_Has_Gone_Before_(episode))", "By Any Other Name (http://memory-alpha.wikia.com/wiki/By_Any_Other_Name_(episode))", "Is There In Truth No Beauty? (http://memory-alpha.wikia.com/wiki/Is_There_in_Truth_No_Beauty%3F_(episode))", "Day Of The Dove (http://memory-alpha.wikia.com/wiki/Day_of_the_Dove_(episode))", and the TNG episode "Where No One Has Gone Before (http://memory-alpha.wikia.com/wiki/Where_No_One_Has_Gone_Before_(episode))". I don't know of any extragalactic travel in the later series.

DaveC426913
2018-Oct-20, 05:43 AM
Travel outside the Milky Way has always been shown as a nontrivial problem of propulsion and navigation. See TOS "Where No Man Has Gone Before (http://memory-alpha.wikia.com/wiki/Where_No_Man_Has_Gone_Before_(episode))", "By Any Other Name (http://memory-alpha.wikia.com/wiki/By_Any_Other_Name_(episode))", "Is There In Truth No Beauty? (http://memory-alpha.wikia.com/wiki/Is_There_in_Truth_No_Beauty%3F_(episode))", "Day Of The Dove (http://memory-alpha.wikia.com/wiki/Day_of_the_Dove_(episode))", and the TNG episode "Where No One Has Gone Before (http://memory-alpha.wikia.com/wiki/Where_No_One_Has_Gone_Before_(episode))". I don't know of any extragalactic travel in the later series.

And you mustn't forget the other one - The Big Scary Galactic Barrier of Scariness surrounding the Galactic Core in "Stark Trek 5 - Kirk Pwns God"

Noclevername
2018-Oct-20, 05:52 AM
And you mustn't forget the other one - The Big Scary Galactic Barrier of Scariness surrounding the Galactic Core in "Stark Trek 5 - Kirk Pwns God"

I think we can safely forget that one.

Swift
2018-Oct-22, 01:12 PM
Travel outside the Milky Way has always been shown as a nontrivial problem of propulsion and navigation. See TOS "Where No Man Has Gone Before (http://memory-alpha.wikia.com/wiki/Where_No_Man_Has_Gone_Before_(episode))", "By Any Other Name (http://memory-alpha.wikia.com/wiki/By_Any_Other_Name_(episode))", "Is There In Truth No Beauty? (http://memory-alpha.wikia.com/wiki/Is_There_in_Truth_No_Beauty%3F_(episode))", "Day Of The Dove (http://memory-alpha.wikia.com/wiki/Day_of_the_Dove_(episode))", and the TNG episode "Where No One Has Gone Before (http://memory-alpha.wikia.com/wiki/Where_No_One_Has_Gone_Before_(episode))". I don't know of any extragalactic travel in the later series.
Even as a kid, I always thought the energy barrier thing at the edge of the galaxy ("Where No Man Has Gone Before") was idiotic.

Noclevername
2018-Oct-22, 01:25 PM
Even as a kid, I always thought the energy barrier thing at the edge of the galaxy ("Where No Man Has Gone Before") was idiotic.

I meant what happened to ships outside of the "barrier".

CJSF
2018-Oct-22, 02:37 PM
I thought the barrier was at (toward) the center of the galaxy??

CJSF

Noclevername
2018-Oct-22, 02:46 PM
I thought the barrier was at (toward) the center of the galaxy??

CJSF

There's one on the outside, at least during the original series.

SeanF
2018-Oct-22, 02:57 PM
Travel outside the Milky Way has always been shown as a nontrivial problem of propulsion and navigation. See TOS "Where No Man Has Gone Before (http://memory-alpha.wikia.com/wiki/Where_No_Man_Has_Gone_Before_(episode))", "By Any Other Name (http://memory-alpha.wikia.com/wiki/By_Any_Other_Name_(episode))", "Is There In Truth No Beauty? (http://memory-alpha.wikia.com/wiki/Is_There_in_Truth_No_Beauty%3F_(episode))", "Day Of The Dove (http://memory-alpha.wikia.com/wiki/Day_of_the_Dove_(episode))", and the TNG episode "Where No One Has Gone Before (http://memory-alpha.wikia.com/wiki/Where_No_One_Has_Gone_Before_(episode))". I don't know of any extragalactic travel in the later series.
Just watched "Is There in Truth No Beauty?" last Thursday (50th anniversary, ya know). After passing through the barrier and arriving outside the galaxy, the problem in getting back in was navigation. It was implied, if not stated outright, that they could move just fine, they just didn't have any reference points to give them a direction in which to move.

Which I thought was odd. We can figure out which direction the Andromeda Galaxy is from here, even though we're well outside of Andromeda. The Enterprise, in "...Beauty?", should've had a big ol' mass of stars in one direction and void in all the others - they couldn't point themselves towards that mass?

Noclevername
2018-Oct-22, 03:01 PM
Just watched "Is There in Truth No Beauty?" last Thursday (50th anniversary, ya know). After passing through the barrier and arriving outside the galaxy, the problem in getting back in was navigation. It was implied, if not stated outright, that they could move just fine, they just didn't have any reference points to give them a direction in which to move.

Which I thought was odd. We can figure out which direction the Andromeda Galaxy is from here, even though we're well outside of Andromeda. The Enterprise, in "...Beauty?", should've had a big ol' mass of stars in one direction and void in all the others - they couldn't point themselves towards that mass?

At less than light speeds, sure, there's light to see by. But FTL, maybe there's no such guide. Maybe the warp goes wonky, sending you off in who knows what direction.

Solfe
2018-Nov-04, 06:02 AM
It seems to me that there are two barriers - the Galactic Barrier and the Great Barrier. They are related and each is torus shaped. I think the original writers likened the Galactic Barrier the aurora borealis. The Great Barrier is from the movies and I don't know what the writing rational was behind that idea. It wasn't a great movie, but did have a great line: "What does God need with a starship?"

Noclevername
2018-Nov-04, 06:14 AM
The Great Barrier is from the movies and I don't know what the writing rational was behind that idea.

It's that Shatner doesn't have a creative bone in his body, and blatantly ripped off ideas from old episodes.

Van Rijn
2018-Nov-04, 07:05 AM
It's that Shatner doesn't have a creative bone in his body, and blatantly ripped off ideas from old episodes.

*shrug* Not that I like that movie much, but it's hardly the only ST movie to use a minor variation on a previously used theme. For instance, KHHHAAAAAAN!

Van Rijn
2018-Nov-04, 07:13 AM
OK, so here's the idlest question of the day (so far).

In the Star Trek universe, one pseudoscience explanation for Warp Speed (FTL) travel, is the existence of an alternate domain of spacetime called "subspace". This apparently acts as an absolute reference frame allowing simultaneity.

My question is, does it have to be an absolute reference frame? Can it merely be a broader "local" than the Einsteinian space we're used to, but still relative?

Going back to this: The absolute reference frame could help giving justification for avoiding trivial causality violations (and they have subspace communication which is near instantaneous over many light years). On the other hand, it's pretty easy to violate causality in the Star Trek multiverse, so it's pointless for story purposes. They even explicitly had temporal investigators that considered a Kirk a menace for all the stuff he messed up in the timeline.

Noclevername
2018-Nov-04, 10:27 AM
*shrug* Not that I like that movie much, but it's hardly the only ST movie to use a minor variation on a previously used theme. For instance, KHHHAAAAAAN!

ST II was a sequel to a TOS episode, not IMO a theft of its plot. ST I for example, was a ripped off plot. It was "The Changeling (http://memory-alpha.wikia.com/wiki/The_Changeling_(episode))" with a bigger budget.


Going back to this: The absolute reference frame could help giving justification for avoiding trivial causality violations (and they have subspace communication which is near instantaneous over many light years). On the other hand, it's pretty easy to violate causality in the Star Trek multiverse, so it's pointless for story purposes. They even explicitly had temporal investigators that considered a Kirk a menace for all the stuff he messed up in the timeline.

But those causality violations didn't happen every time they used warp drive.

cjameshuff
2018-Nov-04, 02:50 PM
But those causality violations didn't happen every time they used warp drive.

Not plot relevant ones, but relativistic travel was rare. Those who didn't have warp used things like slowboats with stasis pods.

The problem with FTL isn't that every usage unavoidably causes severe causality violations even over a limited volume of space containing objects with low relative motion, it's that it makes causality violations possible.

Solfe
2018-Nov-04, 02:54 PM
In my feeble attempts at science fiction, I like to throw causality out the window. Fast movement causes time travel every time. What allows for goofy things isn't the faster than light travel, it's the instantaneous acceleration. If can jump to arbitrarily fast speeds, without being turned to grape jelly, you have cheap and easy time travel. If, on the other hand you need to accelerate for a year to c, well, it is still time travel but ineffective time travel. On human terms, you can safely ignore it. You can't shift perspective to another group of characters, otherwise the paradox creeps back in.

Maybe this is why my attempts at writing are so bad. I created cases where characters are clearly traveling in time, but ignore it. A deep read makes that very clear, which in turn makes for funny, brain busting situations if you think too hard. For example, planets usually have navigational sats to assist ships. Sometimes, they breakdown and the ship itself will replace them using an FTL device to get them to the planet before the ship gets there. Then a character will comment that "Oops, I see the nav-sat. We just wasted a perfectly good nav-sat. Oh, well two is better than one." No! The sat that magically appeared was the one launched by the character traveling in time, there aren't two of them.

Star Trek seems to waffle between slow acceleration to high speeds and fast acceleration to non-paradox causing speeds. Either one would create paradox free scenarios for the crew of the ship because they aren't going so fast they can meet themselves. But other people at a distance would see all kinds of paradoxes.

Kind of like Nightcrawler in the X-men movies. He teleports not quite instantaneously, but much faster than people can turn and look at him. He is "invisible" in tight, confined spaces. Someone at a distance would see that his opponents simply can't turn around fast enough. In the comics, this is one of his "tropes" and pairs with his ability to cling to walls and ceilings. He won't land in a place you'd expect. That would be super-creepy vampiric threat, but he's a very pleasant individual which counteracts the creep factor. Nice trick. It works on so many different levels.