Let's time travel, shall we?

[Yog-Sothoth]

I have been having some issues regarding time travelling. Here is the first issue in my story:

A young boy is forced into battle with a powerful opponent far older and experienced. This boy's fate would be; certain defeat and in the process the loss of his left hand, but in the heat of the battle an older version of himself, extremely powerful, intervenes and defeats this enemy. However in that brief moment, I have provided the reader with a semi-detailed description of the stranger with the highlight being his mechanical/futuristic left hand.

In my story this older version of the boy after defeating this enemy, takes a look at his left hand and notices that his futuristic mechanical hand has been replaced by a perfectly healthy hand, because of his victory.

I don't know much about time travelling and all the linear and non linear schools of thought, but would you buy the above in a story if you read it? This is not intended to be Hard SF, so the ramifications that come with him saving his younger self of an already happened incident (which could risk changing his own life and road to powerdom, as the incident might have shaped him to become so powerful) isn't really relevant.

What I do care about is whether I have unintentionally crashed into an alternative reality with this intervention? In my opinion that wouldn't make sense as this older version would not experience the regeneration of his left hand if that was the case, since in an A.R scenario he would be the older version of a different young boy, the one that did get his hand cut off, and so his futuristic hand would remain the same.

You see what I mean, it makes my head spin, and gets me all tired and stuff.

 

[Jake Reynolds]

"the ramifications that come with him saving his younger self of an already happened incident (which could risk changing his own life and road to powerdom, as the incident might have shaped him to become so powerful) isn't really relevant."

It totally is, since that is what the story seems to be about (otherwise why bother going back to save one's own hand. I like the idea though, but it just needs to be clear what is happening, and more importantly, why.

Given that robotic hands seem functional, would someone go to the trouble of going back in time to stop it from happening to them?

If I was writing the story, I would have this event based around the future tough guy deliberately forcing a paradox to effect time itself, for an entirely different reason. Say, for example, he is in the middle of a pitched battle with the big bad guy at the end of your book/ story, and then suddenly realises that a forced paradox can save the day, by undoing the timeline mischief the bad guy has been up to.

He therefore chooses an incident in his life that was crucial to him being where he was, then went back and intervened, thereby causing a paradox that destroys the bad guy's machine in all time and space, undoing all that it had done and saving the day.

Or something like that. The problem with time travel is that it will get queried either way, whether hardcore SF or not. I think you need to clarify:

a) why his future self came back (for a better reason than simply wanting a flesh hand instead of a fully functional [and probably cooler] robot one), and;

b) how time travel is possible. Do people do it willy nilly? How easy is it? Presumably it is simple enough if people are jaunting off just to get hands replaced.

Sorry this reply is a bit all over the place (much as writing time travel is). Also, remember that readers won't be finding out about this until the very end, since we don't know who the tough guy is, and since the boy doesn't lose his hand there is no connection at all.

Hope this helps.

 

[Boneman]

Watch 'Frequency' with Jim Cavazeil and Dennis Quaid... great bit of hand losing shenanigans goes on there...

It's a chicken and egg situation, and I'd just do it and ignore the time paradoxes - it sounds like a great idea!

 

[Yog-Sothoth]

Dubrech, great minds think alike huh? The bad guy is his childhood best friend that gets WAY to powerful for his own good, and ends up literally destroying the planet, but not before the guy with the futuristic hand manages to snatch a timemachine and travels back to their younger years.

His intention behind travelling through to time wasn't really to intervene in that specific battle, he just remembered that on this day he would face a enemy far more experienced than his younger self, an enemy that would disappear soon after. This is something that would frustrate him for many years to come as his powers grew stronger. Hence he thought why not engage this powerful opponent in this specific timeline and finally take revenge?

Also the reader probably will see a connection when the Future guy notices his left hand return to flesh. As the enemy (the younger boy was fighting) is known to cut off the hands of his opponents as trophies, and right before the Future guy intervened, he was about to do the same to the boy.

Boneman, thanks for the suggestion, I will look that one up, and I agree, if I allow myself to be shackled by the contradicting laws of time, I might aswell call it a day.

 

[Boneman]

And don't forget: in the future, yoiu've already given up allowing yourself to be shackled by time laws, so you don't have to worry about it...

 

[paranoid marvin]

Maybe when he returns to his own time the hand returns , as he's still in the past? Maybe gradually over time the skin heals and the mechanical hand becomes flesh.


You have to ask WHY he would return to the past though ; is he so bothered about his hand that he would risk altering the space/time continuum , or has he an ulterior motive? Would he not by this time have grown accustomed - maybe even prefer - the benefits of a mechanical hand to that of a normal one.

whatever ypu decide it's outside of the laws of reality as we know it , so pretty muchanything goes.

 

[chrispenycate]

No, I don't believe the hand grows back.

You've basically got two choices; either you went back and prevented the amputation, in which case the hand was never lost, because you appeared and defended yourself, or we have a "what happens to a dog when you cut its mother's tail off" grandfather non-paradox, where the fact of you travelling in time creates an alternate universe at your arrival. But then you are divorcing yourself totally from your origins; all the actions you were going to take will be eliminated, but the experience you gained from them stays with the older you –as do all the scars. If the memories remain, so do the prosthetics.

Temporal hysteresis where history slowly adapts to change (as in Silverberg's "Up the line") requires an "overtime" in which temporal modification can take place, which is the start of an infinite regression, and almost always leads to paradoxes that can't be paradoctored; better that when change occurs it has instantaneously always been like that, rather than trying to document successive layers as in Benford's "Timescape"; because the number of layers would always fill all available information space, only avoiding infinity because, ultimately, one of the changes would cause time travel to be never invented, and everything would settle down to a single timeline, content with causality.

 

[Nik]

Uh, can I hear StarWars theme playing some-where ??

FWIW, temporal paradoxes and loops are great fun-- But we grew up with Doctor Who !!

 

[Yog-Sothoth]

No, I don't believe the hand grows back.

You've basically got two choices; either you went back and prevented the amputation, in which case the hand was never lost, because you appeared and defended yourself, or we have a "what happens to a dog when you cut its mother's tail off" grandfather non-paradox, where the fact of you travelling in time creates an alternate universe at your arrival. But then you are divorcing yourself totally from your origins; all the actions you were going to take will be eliminated, but the experience you gained from them stays with the older you –as do all the scars. If the memories remain, so do the prosthetics.

Temporal hysteresis where history slowly adapts to change (as in Silverberg's "Up the line") requires an "overtime" in which temporal modification can take place, which is the start of an infinite regression, and almost always leads to paradoxes that can't be paradoctored; better that when change occurs it has instantaneously always been like that, rather than trying to document successive layers as in Benford's "Timescape"; because the number of layers would always fill all available information space, only avoiding infinity because, ultimately, one of the changes would cause time travel to be never invented, and everything would settle down to a single timeline, content with causality.

Oehh, good post. Here is a scenario; a young boy has dreams of becoming a famous painter, however massive domestic abuse inflicted upon him at the hands of a sick individual causes him to become a serial killer. Let's say the adult version in a future era manages to covet a time-machine and see him travel back to the period those abuses occured, and to prevent it from happening, he kills the specific person responsible, resulting in the kid becoming the famous painter he always wanted to be.

Here comes the difficult part, would it make sense for this older wretched version to experience a transformation into a healthy looking human being because his intervention prevented the abuses from happening? Huh? Arggh!!, now i'm beginning to chase my own shadow again:

1) Why would the older version enter a time-machine if he was never abused and instead had become a successful painter?

2) If there is no one entering the time-machine who would prevent the abuses?, and we are back to square one.

This is one of the reasons why I have obliterated the future where the older version in my story comes from. He instead is helping this younger version into molding a new future, since in his time there is no present or future anymore that could be changed by anything in the past. However since they are made of the same material (though from a different timeline) any changes physically on the younger version will be immediately evident on the older version. The boy will grow up to become a less war-torn/combative(though still powerful) version of the time-travelling guy. The latter can't return to the future he came from, so he eventually grows old and becomes part of this new future. Basically they have become their own entities, though anything happening to the younger version can still affect the older one.

A) It has become an alternative reality.

B) Changes in this past won't affect the history the older version went through or see the loss of his memories, its strictly physical.

C) Since there are two pasts but only one continues future(the one of the boy), the older version will still enter that time-machine to go back, since his past is still the same, but him being in this new version of "reality" allows for physical changes, both good and bad.

D) Since the future of the older version no longer exist, there is no scenario of him returning to a future different self, he has already met him; the younger one he saved that is now living out this newly created future.

E) Physical changes such as the regeneration of the hand will be explained as them being made of the same material, one being younger and one older. If the older and younger version were to go further back in time, to the period they were still a baby, any physical changes on the baby version would instantly show on them, as they are made of the same material, and because they are physically present in the timeline of the baby.

Does that make sense?

 

[J Riff]

It makes as much sense as time travel itself does.. the only problem may be confusing the reader with a bit too much info about the nuts n bolts of time travel. The story sounds good so it should work whichever option you plump for.

 

[Karn Maeshalanadae]

Actually, not only is there Frequency to reference, but also Timecop-which is really a crap movie, if it's the one I'm thinking of-and The Sound of Thunder-the story, NOT the movie.


The theory on time travel is that if you travel backwards through time, certain actions can and will influence events in either a direct or indirect way and will cause a pyramid situation, where it just keeps expanding and expanding as time goes on until the original "present" events may not even be possible anymore. So it is entirely acceptable that the boy's older self defeating his childhood enemy before the enemy takes his hand will make it as if the older self had never lost his hand-because, in effect, he hadn't.

But if you follow that sort of time line, I would also suggest that you not have the younger boy come in contact with his older self as a time travel physics law would state that they would not be able to occupy the same space at the same time.

 

[Boneman]

But if you follow that sort of time line, I would also suggest that you not have the younger boy come in contact with his older self as a time travel physics law would state that they would not be able to occupy the same space at the same time.

Spock did it...

 

[Jake Reynolds]

Ah, geez, you take your eye off the forums for one night and everything goes superstential.

I think that, as with almost anything you wish to write about, if you drop little, almost unobstrusive nuggets into the story, you can pretty much do anything. Star Trek is a great example, with the whole 'insert technobabble here' situation, i.e. just whip up something finctional to explain why your story is possible. As long as you don't do it in a deux ex machina way right at the end, it should be ok for th emost part. However, you will have time travel afficianados querying it, that's unavoidable. Roll with it.

 

[chrispenycate]

But of course I'm going to argue the cause of causality; isn't that what I'm here for?

And I question that "same material". Over the course of a few years almost all the atoms will be replaced, certainly in living tissue. The only continuity is early (pre arrival) experience, genetic structure and the questionable 'soul'. In fact, a couple of identical twins, one much older than the other, rather than a mystic equals sign. Experiences change people, and the do-gooder with his artificial hand who crashes in from the future is not the same person as the inexperienced victim he's saving while, in doing so, condemning to non existence (not merely death, but never having come into being) all the beings he would have come into contact with in the intervening years; babies never conceived, enmities never resolved, life choices butterflied out of existence for one individual's convenience.

Mind you, it's easy to see this happening all the time anyway, with no requirement of time travel.

And matter occupying the same space at the same time is inconvenient in this universe anyway, without it requiring to be a doppelganger. The idea of a 'critical distance' is muddy. Seeing the other side of the street? Making physical contact (very popular in supernatural stories)? Simply existing in the same universe as, at the same temporal location? (frequently used to prevent time travellers from clearing up the messes they have made, but if the molecules of which they are constituted exist anyway, and their bodies are being constantly replaced, where's the extra problem?)

So, don't try and exist in the same space as any other matter, be it yourself, a stone wall or a you shaped bit of the Pacific ocean. It's not healthy. When time travelling, don't shake hands with (or, in the case of "all you zombies", attempt copulation with) anyone you suspect might have been you, or might be going to be you; you might be in a fantasy story instead, and both of you "suddenly, silently, vanish away" And don't consider that prevention replaces surgery; that prosthetic is from your past, not his future, and the two are no longer the same

 

[Yog-Sothoth]

Karn, Timecop is the whole reason behind me brainstorming a time-travelling story that lacks the thousands of paradoxes its movie writers overlooked, only to be decimated by Roger Ebert in a devastating review, where he picks apart the entire story.

Dubrech, you right, its better that I just invent some fancy futuristic word to legitimize everything, maybe excuse some of it with the supernatural card, that one and the magic card always do wonders for me.

Chrispenycate, I have made up my mind; this is my universe, not the universe observed by our Physicists. In my universe two objects of the same material are capable of occupying the same space and time, just like two clones made of the same material can. However since the Future guy is the sole representative of a timeline that no longer exists, and also is the future version of the boy(and the boy of a different past that did get his hand cut off), any physical changes will be apparent on the former, such as the sudden disappearance of his mechanical hand, because of the Yog Sothoth Equilibrium.

 

[Junsui0110]

This is one of the reasons why I have obliterated the future where the older version in my story comes from. He instead is helping this younger version into molding a new future, since in his time there is no present or future anymore that could be changed by anything in the past. However since they are made of the same material (though from a different timeline) any changes physically on the younger version will be immediately evident on the older version. The boy will grow up to become a less war-torn/combative(though still powerful) version of the time-travelling guy. The latter can't return to the future he came from, so he eventually grows old and becomes part of this new future. Basically they have become their own entities, though anything happening to the younger version can still affect the older one.

A) It has become an alternative reality.

B) Changes in this past won't affect the history the older version went through or see the loss of his memories, its strictly physical.

C) Since there are two pasts but only one continues future(the one of the boy), the older version will still enter that time-machine to go back, since his past is still the same, but him being in this new version of "reality" allows for physical changes, both good and bad.

D) Since the future of the older version no longer exist, there is no scenario of him returning to a future different self, he has already met him; the younger one he saved that is now living out this newly created future.

E) Physical changes such as the regeneration of the hand will be explained as them being made of the same material, one being younger and one older. If the older and younger version were to go further back in time, to the period they were still a baby, any physical changes on the baby version would instantly show on them, as they are made of the same material, and because they are physically present in the timeline of the baby.

Does that make sense?

Material can't exist in two places at once.
The body regenerates all the time, and as such old material is eventually lost or changed in some way.
By the time this guy was old enough and powerful enough to affect his own past, the chances of him retaining the exact same material as he was made of as a child isnt very high. Not only has his body grown in size, but also a large portion would have been recycled into the body and broken down to become new material.

When he goes into the past and changes a fairly important part of his life, he is destroying his own personal future. By sticking around and teaching the kid a few things, and changing a lot of experiences the kid would have gained, he is in essence breaking the timeline cycle.
They become two very different people at this point. The hand would not grow back, the time machine probably wouldnt function anymore and the kid would probably have no reason to grow strong anymore.
As it stands, it looks like the entire reason the kid got strong in the first place was for revenge. When you go into the past and remove that drive, you remove the resulting ability.

Anyway, those are just a couple of my thoughts on the subject. I know they arent very well put together, or even fully formed. I apologize if it's no help at all.

 

[Ursa major]

* Head spins from considering time paradoxes. *

Can I suggest Giving a Hand as the title....

 

[Karn Maeshalanadae]

Spock did it...

Yes, but Star Trek didn't follow those physics, did they?


And Yog, Timecop was only one example of a story setup-and I didn't say it was a good one. All I suggested was that if he chose to follow through with ITS physics, not to have physical contact between the two selves.


Personally, I don't think there is any one route to go with the issue of time travel. There's all sorts of things to be considered. How time travel is achieved, for example, is a complicated enough issue. You can choose to go warp speeds opposite a solar system's rotation the way Star Trek did it, you can do it by having wormholes to different dimensions where time is weak, etc.

Then there's the physics of the double self. Never mind the paradoxes.

 

[Dave]

I was going to say something, but then I see Chris has made a better reply than I ever could.

I have made up my mind; this is my universe, not the universe observed by our Physicists.

In that case, you are writing Fantasy and not Science-Fiction. I'm not saying that there is anything wrong with that, in fact, you could go on and write anything which followed you 'own' set of rules, and no one could fault you, ever! However, I'd still urge you that for some kind of consistency, you need to either stick to a 'Linear' idea of Time, or the 'Many Universes' idea. Swapping between the two when it suits (which TV shows frequently do) is something I hate.

 

[Jake Reynolds]

Hey Yog,

A further idea just came to me- remembering First Contact, the Enterprise isn't effected by temporal changes because they're caught in the Borg's temporal wake when they time travel. Perhaps some kind of temporal shielding might be useful? However, then you have to deal with several other issues that arise, in that the shielded would effectively not exist as they would be existing outside of time.