Limits of Time Travel

[WarpTenLizard]

I'm asking mainly for a fanfic story I'm planning, but also simply as a Trekkie trying to make sense of the series.

While time travel is by no means easy in the "Star Trek" universe(s), it's common enough that it's a seriously considered option for a variety of dilemmas, from not being satisfied with the hand fate delt your crew, to thinking that a couple of humpback whales would really be helpful right now.

Of course, time travel comes with all kinds of massive risks. But what you might think is the biggest risk of all, apparently....isn't. In "Star Trek," if you go back in time, and take actions that change the course of history so that the timeline you came from never existed...you still remain. Tasha Yar in "Yesterday's Enterprsie," Admiral Janeway in "Endgame," not to mention all the career time-travelers we encounter throughout the saga. Not only can you continue to exist without your timeline, but you can co-exist with your other self. On "Voyager" a name was even coined for this phenomenon: a Temporal Clone.

The only time I recall a character disappearing with her timeline once she altered history was Molly O'Brien, in the infamous DS9 episode "Time's Orphan." And it may not be an inconsistency. Because Admiral Janeway and Tasha Yar were not in their timelines when those timelines were erased. Molly on the other hand helped her younger self walk back through that temporal rift, staying behind in the timeline she came from, and thus vanishes with it. So, it seems that if you make the mistake of going back to your timeline before it's erased, you go with it, but if you stay in the past, Father Time gives you a pass.

Long story short: in "Star Trek," time travel is very common, and you can use it to create multiples ("Temporal Clones") of the same individual.

So now I ask...what are the limits?

Why doesn't the Federation use time travel to create Temporal Clones of its best ships and officers, during war time? What's stopping 99% of grief stricken people from using time travel to change fate? Why isn't anyone attempting to use time travel to cheat death forever? What reasons, other than "muh Temporal Prime Directive/Preserving the Timeline."

I'm looking for real limitations to Time Travel.

Either possible rules that could limit what you can do with time travel in the "Star Trek" universe, or longterm consequences of time travel that might make being a Temporal Clone a fate worse than death.

Some ideas I've come up with so far:

• Insanity. Picard once suffered Temporal Neurosis, and Braxton has Temporal Psychosis. We didn't see Tasha Yar in her three years as a Temporal Clone, so she could have suffered ill effects for all we know.
• You WILL disappear, eventually. Tasha Yar is the only Temporal Clone I can think of who actually lasted beyond the initial adventure that created her. Temporal Clones have a tendency to sacrifice their lives to save their younger selves, almost immediately after creation. Maybe if your timeline vanishes, you eventually will too, but it might just take a while.
• You can't just travel to wherever and whenever you want. Maybe you can only "jump" to spots where enough tachyons are in the air, or some crap. Voyager, by Season 7, would be packed with tachyons from all its previous time travel adventures, whereas Janeway's father who drowned under an icecap probably never did any time traveling. So maybe that's why Janeway decided she could go back to change Voyager's fate, but not her father's.

I'd love to hear some other ideas.

 

[publiusr]

Look up Germain Tobar’s paper on paradox free time travel.

 

[Lord Garth]

I'm of the belief that once you go back in time, you create an alternate reality. Your presence changes reality from the way it was before.

I also think that the timeline branches out. You have one reality where you turn left (Reality A) and another where you turn right (Reality B). In Reality A, you can then turn right next (Reality AA) or you can continue going left (Reality AB). In Reality B, you can do the same turn left (Reality BA) or right (Reality BB). And it keeps branching out from there. So I think we have an exponential number of possible futures that all fold back into one Common Past. One common root. One family of realities. You can also have a whole other family of realities that have nothing to do with this at all.

So once you go back into the past, you can never return to the same exact present you left. If you change something in the past, you just create a new branch of realities.

 

[Timo]

You can only do those trips the majority of time travelers agrees with. Otherwise, the majority will simply undo your trip to the past, and somehow this will manifest as your inability to perform the trip in the first place.

I mean, the universe offers billions of years during which quintillions of time travelers will be practicing their art - and with the machines, they won't be limited to mere billions of years, either. In the Milky Way, most of the time travelers are humans with funny foreheads. So, after the frenzy of doing and undoing and redoing is said and done and finds an equilibrium, time is us, perfectly reflecting human desires and perversions. So heroes and villains may struggle, but only in approved ways, and on an arguably positive note, heroes triumph and thus are in the majority. After all, the Milky Way is still here...

Timo Saloniemi

 

[1001001]

Look up Germain Tobar’s paper on paradox free time travel.

Or watch the 2002 The Time Machine.

Same argument, right? The timeline repairs itself to avoid the paradox. His girlfriend just died a different way.

So basically you can travel to the past, you just can't do anything there.

 

[Joanna McCoy-Kirk]

There is a new article on the National Public Radio site about a recent Australian scientific paper on paradox-free time travel: https://www.npr.org/2020/09/27/9175...vel-is-theoretically-possible-researchers-say

 

[somebuddyX]

I don't know if this is what you were after but my favourite limitation for time travel was in the TV series Time Trax where the human body could only travel through time twice, usually one trip back, one trip forward, otherwise the time travel process killed them. This is how I wish the Temporal Cold War was used in Enterprise with the time travellers stuck in the 22nd Century or like the Sphere Builders they were able to visualise alternate futures through precognitive abilities or maybe through predictive patterns like psychohistory but no actual time travel like in "Azati Prime" or "Carpenter's Street".
Along with all the new tech and aliens and characters that should make huge impacts on the Trekverse and doesn't, I think you just to have to include time travel in it. It would be great if there were logical reasons for why time travel wasn't known, because knowledge was withheld or hard to do or the time cops kept erasing the knowledge from people's brains or something, but then there's things like the Orb of Time just sitting on a shelf in the Bajoran temple and Sisko basically saying "Sure Kira, you can borrow that to go hang out with your dead mum and almost kill Dukat several decades ago, no worries mate."
Maybe different types of time travel have different results. The time travel in "Children of Time" only allowed one timeline to exist whereas "Yesterday's Enterprise/Redemption" clearly allowed multiple timelines and "Star Trek 09" shoved everyone into alternate universes. And is Data's head still buried in San Francisco in the Kelvinverse? If Pine Kirk went back in time to 1986 would he bump into Shatner Kirk? There's sixty gajillion ways to time travel now so each one probably has different consequences.

 

[BillJ]

No limitation, just the various powers keep a lid on it. The general public knows nothing about it. Former or Current Starfleet officers who start talking about it end up in unfortunate "accidents".

 

[DonIago]

I agree with what was said above. When you travel into the past you're either creating or "jumping tracks to" an alternate timeline. It may be almost entirely identical to the timeline you're familiar with, but it is nevertheless different.

But then, one could argue that the same principle applies to stepping through a transporter.

Of course "Parallels" establishes that you can return to your original timeline via quantum signatures and such, but if your goal was to "change history", then you'll just be returning to the very timeline you tried to change.

Alternately, it's all Predestination Paradoxes.

 

[Orphalesion]

I will be honest, I never liked time travel, and aside from maybe "Wrongs darker than Death or Night"(where I still have to ignore the silly idea of Kira being allowed to causally time-travel) and "Year of Hell" I don't like any of the episodes and I would probably have liked Enterprise better without the Temporal Cold Wart nonsense.

It was just never something that particularly interested me.

Personally I prefer the "Everything is a Predestination Paradox" since it keeps things neat and tidy.

Edit: Wait, I don't think Year of Hell even counts as a time travel episode...

 

[Oddish]

Time travel is limited by what your audience is likely to find interesting.

Truth is, time travel will probably never occur. Reason I know this is that if it did, someone would certainly have done it, then done something to prevent their initial trip, igniting a grandfather paradox. The entire four-dimentional universe, from big bang to heat death, would have been erased like a soap bubble popping, and I would not be around to type this message into my smartphone.

 

[1001001]

Time travel to the past is, I think, impossible. Ignoring the paradox problem for a second, if I travel back ten years to meet myself, where did that extra matter come from?

Time travel to the future (via dilation) is not only possible it’s already happened.

https://www.chonday.com/timetrspace18/

 

[Silvercrest]

Time travel to the past is, I think, impossible. Ignoring the paradox problem for a second, if I travel back ten years to meet myself, where did that extra matter come from?

If you think about space-time (and the multiverse) as a mind-bogglingly large closed system, it's not "extra". Nothing has been added to it; one human's worth of mass has merely been shifted from one part of the multiverse to another.

Truth is, time travel will probably never occur. Reason I know this is that if it did, someone would certainly have done it, then done something to prevent their initial trip, igniting a grandfather paradox. The entire four-dimentional universe, from big bang to heat death, would have been erased like a soap bubble popping, and I would not be around to type this message into my smartphone.

I like the "self-correcting" model, which is: The time machine will never be invented. Yes, time travel is possible. But if a time machine is invented, sooner or later someone will make changes to the past that will screw up the circumstances of its invention. Therefore, the time machine will never be invented.

 

[Oddish]

For some reason, the self correcting model sort of reminds me of "Sliding Doors", starring Gwyneth Paltrow. Most of the movie is about the vastly different directions a person's life can go in based on one event (making/missing a train). Then, at the end, self correction kicks in, pushing her character toward what was "meant" to happen.

 

[hbquikcomjamesl]

It seems to me that the rules are different, depending on whether it's via the Guardian of Forever, the Atavachron, a slingshot effect, an implosive cold-restart of a warp drive, whatever Daniels uses, whatever "Future Guy" uses, whatever the Aegis uses, or Georges Mordreaux's device from The Entropy Effect (did I leave anything out?). Which probably makes the DTI's job harder.

 

[WarpTenLizard]

...if I travel back ten years to meet myself, where did that extra matter come from?

Sir, you may have just struck gold for me! If I decide to use this issue on my story I will credit you!

 

[BillJ]

Reason I know this is that if it did, someone would certainly have done it, then done something to prevent their initial trip, igniting a grandfather paradox.

If someone time travelled, even to your city, the odds of you knowing about it would be incredibly remote. The time traveler would actually have to promote they were from the future and prove it. Which wouldn’t have any benefit for them.

Think of Rasmussen from “A Matter of Time”.

 

[Oddish]

If someone time travelled, even to your city, the odds of you knowing about it would be incredibly remote. The time traveler would actually have to promote they were from the future and prove it. Which wouldn’t have any benefit for them.

Think of Rasmussen from “A Matter of Time”.

Depends on how far back I jumped. The farther you go, the more time the butterfly effect has to mess things up. Especially since you really don't have to do much to prevent the conception of a given baby.

 

[BillJ]

Depends on how far back I jumped. The farther you go, the more time the butterfly effect has to mess things up. Especially since you really don't have to do much to prevent the conception of a given baby.

How would you know if someone else did it? Your memory would adjust accordingly.

 

[XCV330]

Time travel to the past is possible if causation is only a concept but not an actual universal concept. If time is actually more of a tableau, then visiting parts of it and changing it up has no more effect than dabbing graffiti in the lower right-hand corner of the Mona Lisa would affect her forehead.

But these are Star Trek Laws of Physics, and they are more like suggestions. They change episode to episode.

Whatever was done in TVH only had effects on future events (unless transparent aluminum was created in San Francisco in the 1980s due to a divide by zero loop) by the physical transfer of wales to the 23rd century . But then it has also been shown in stories like City on the Edge of Forever and First Contact that traveling into the past could and would effect the future. (likewise in the Temporal Cold War).

Star Trek has, as usual been inconsistent with itself, in this regard. In some cases events like the Enterprise C incident or the Anti-Time (and I suppose the Year of Hell) create tangential universes, to steal a term from Donnie Darko. These pocket realities are not entireties but are fixated around one event. They can repeat, they can end. Other events like the Kelvin incident (and possibly the timeline Janeway abandoned) create entirely new timelines, or else timelines that were always there waiting for someone to cross over into.

so star trek's answer to time travel seems to follow one of three options:
1: doesn't matter
2: does matter but only in a limited, repairable sense
3: creates a whole new goddamned universe

I can see why the Temporal cops have no sense of humor.