Does this work---

If you are traveling in time, can you be in two places at once? Like this—a man leaves for the past at 3am---ok he spends time in the past until say 3:30---then he goes back to the future and arrives at 3am—it would then appear that he never left—right? He stays in the future until 4am then he goes back to the past and appears there at 3:30---it would then appear that he never left the past—right? So he would be in both places at once, but not really. Or am I clear as primordial soup?

He would then have a strange mixed mess of memories—or wouldn’t he? How would you show this? Can it work for a long period in which the writer shows only one time period? Then when he returns, those in the other time period think that he was there all along and did things as well---but he has only vague memories of it? Or do I need to show one of the shifts and what he does in each to make it work ?

Bad example follows:
I was sitting with the cat and then suddenly I was looking at my mother who had been dead for five years. I look at the calendar and realize that if my mom goes to the store today she will be killed.---I say, “Mom, don’t go to the sto---then I was looking at the cat again---I fed the cat and walked outside—if only I could figure out why I kept shifting this way---re today.” And I was looking at my mom again as if I had never left her. Or maybe---re today?” “Son, are you all right?” What the hell had just happened?

Does that work?

Comments, suggestions? Please, this is a major factor in making my novel work!

Shawn

I think that you're running into one of those weird paradoxes where Something would prevent that from occuring. Not sure if it's just a commonly held "writer's belief" or if it's actually what theorists suppose, but I've read that there are certain paradoxes to time travel that just won't let you do certain things... such as inadvertently killing your grandfather or bumping into yourself or being 2 places at the same time. AND even if all of that were just a writer's convention, it's probably a reader's convention as well, and you might have to explain your way out of that paradox in your story.

Just my 2 cents. Not sure if that was helpful at all!

<<If you are traveling in time, can you be in two places at once?>>

I think no. I'll explain.

<<Like this—a man leaves for the past at 3am---ok he spends time in the past until say 3:30---then he goes back to the future and arrives at 3am—it would then appear that he never left—right?>>

He travels in the past at 3 a.m. Then, waits until 3:30 a.m. Then-- He goes to the Future at 3 a.m., you say? But that's the Past now, for him! (since he is at 3:30) So he isn't at two places at once.

<<He stays in the future until 4am then he goes back to the past and appears there at 3:30---it would then appear that he never left the past—right?>>

First, he goes to 3 a.m. Then, waits untill 3:30. Then, goes back to 3 a.m. Then he stays there --in the Past, not the Future-- until 4 a.m. Then, goes back to 3:30. Right? I'm a bit comfused...
I really think this guy is sliping to and fro in the timestream, but he isn't at two places at once; he is just moving up and down the Road of Time. Can you be at two places in a road? (Supposing you use time like a road, for there are also other explanations.)
The whole thing depends on what he does when he is in the "Past" or "Future" (which are subjectif, and related to the man in question, actually). That is what is more important. His memories will remain as they are: he will remember exactly what he sees, normaly --except if you're using some other explanation (a dream, parhaps?).

I can't a problem about being in the same place at the same time. The YOU at any given time is the YOU at that time only. .00001 second later you are a different YOU than the YOU at .00001 second before. The existance thing isn't a static event; any micro-moment change in a person takes him/her away from the before.

I think I have it worked out so it makes sense---though to explain how I did it would make your head hurt and mine.

Seriously, you can do whatever you want to do in your stories, just as long as you can get your readers to go along with it.

In the Asimov novel The End of Eternity time travellers were constantly changing history. In OSC's Pastwatch: The Redemption of Christopher Columbus time travellers could change history. Both are among the most respected of authors.

You begin to lose your readers when you start messing with causality. If I am sitting here at 3:00 AM and I suddenly see myself time-travel in from the future, the future me should already have memories of the event. If not, I had better explain why.

It was bad a example---I was trying to explain the effect I was going for---at the point in the novel he doesn't know how he is traveling yet---he does figure it out. And the scene was not out of the novel---good grief if I wrote like all the time I would have given up long ago---it was a quickly put together example in the middle of a brain storm on how to get the scene to work. Plus--the entire novel has an edge of the surreal to it.

quote:

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Can you be in two places at once?

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anybody familiar with CPT symmetry? i use it to rule out time travel in my sci-fi. i'll explain:

for a while it was accepted that the universe obeyed three symmetries: C, P, and T.

C: laws (of the universe) are the same for particles and anti-particles
P: laws are the same for particles and their mirror images (particles spinning left-handed and right-handed, for example)
T: if you reverse the direction of motion, a system will go back toward its origin (laws are the same forward and backwards in time, basically)

it was later found that the weak force doesn't obey C or P, but does obey CP

even later it was found that K-mesons don't obey CP

long story short, this shows that if you reverse the direction of time, the universe doesn't behave the same way. when you come out of it, the universe you're in will NOT be the past. so much for a road...

still, there are tons of other ways to time travel if you want to. i, for one, incorporate exotic matter (negative energy) feilds to escape light speed problems. that's sorta like time travel, and exotic matter feilds can also be used to maintain wormholes for time travel, if you want time travel.

i hope i haven't made things worse...

TTFN & lol

Thanks

Oh boy---

And, yes, there possible time-dimensions where I've never writen this post.

There are other possible time-dimensions where Shawn hasn't started this topic.

Other references such as in role-playing typically you can travel back in time but not make a major influence. Like if you kill a general who won a major battle history changes slightly and instead one of his soldiers stepped in and the same result ensued.

Also you being out of the time loop would be the only one not affected by the changes. Everyone else would think that is the way it always has been so you pose the danger or maybe affecting events you don't totally understand if you were to take that angle.

But in truth I am sure you can do just about anything you want being it if fantasy. (Micheal J fox almost met himself in Back to the Future).

Seriously, if you recall the second movie in the series, Doc Brown almost met himself while stringing up the cables, and Jennifer did meet herself. These encounters and their effects really give no information to which any writer must adhere, unless you are writing the script for Back to the Future: Part 4.

your question reminded me of a funny story. i don't remember all the details, but here's a paraphrase:

A baby girl is abandoned and left at an orphanage in 1945 and grows up lonely and depressed. One day in 1966 at a bar she finds a lone, drunk vagabond with whom she can relate. She feels as though he knows exactly what she's been through and the two fall in love. they share a night together, but he disappears the next morning. Nine months later she gives birth to a baby girl, but something goes terribly wrong with the birth. It turns out that the woman has both male and female sex organs and in order to save her life, must be turned into a boy. Depressed with her fate, the now man becomes a drunk vagabond. A month later (s)he meets a middle-aged male who says he is from the Institute of Time Travel (something like that--i can't recall the actual name) in 1985. He gives (her)him the opportunity to seek revenge on the drunk who left (her)him in this state in 1966, but first (s)he must do two things: 1)leave his baby girl at an orphanage in 1945 and 2) join the Institute after getting his revenge. The man agrees, drops off the baby in 1945, and then travels to 1966 to the bar where he met the vagabond. At the bar, he can not find the vagabond and drinks heavily to stay his depression. He then meets an oddly familiar woman. She seems to understand and relate to him very well and the two spend a night together before he must leave to join the Institute of Time Travel. There he becomes a prominent member and in 1985 gets his most daring mission yet--go back in time and lead a young man to confront the father of his child.

can you imagine THAT family tree?!

TTFN & lol

Cosmi

thanks. i read it in some science book (they've begun to mush together {sigh}) and couldn't recall any more about it. i didn't know it was by Heinlein. actually, i've always been a fan of his so that's neat to know.

thanks again.

TTFN & lol

These two questions actually have nothing to do with each other, so they must be answered separately.

Time travel is possible, since we all travel forward in time. It is also possible to exert some control over the rate at which time passes, as we learn from relativity. There is no theoretical exclusion of traveling backwards in time either, although Cosmi is correct in postulating that some forms of reverse times may not display perfect symmetry. Thus, the time inversion would not lead to a previous time, but rather a "past" logically consistent with the "present" from which you travel. Because this form of time travel does not involve paradox--at least not as such--it cannot be ruled out as a theoretical possibility (I will point out that this type of time travel does involve inverting the fundamental physical constants in such a way as to make some substantial part of the universe go in reverse, so while it is not impossible, it is certainly quite difficult).

More recent speculation involves the possibility of using a wormhole to travel between two points. If one entrance is kept stationary (or nearly so) while the other end--let us call it the y end, meaning the young end--is accelerated to the speed of light and taken on a round trip back to it's point of origin, then you will have a pair of "portals" that are connected. If you go into the first opening that is, say, 100 years old, then you will come out of the y opening when it turns 100, i.e. nearly 100 years after you entered its mate. To you this will seem instantaneous. There is no physical principle that prohibits the return trip, entering the 100 year old Y end and coming out the first end when it was 100 years old (or slightly after you entered it). Having returned to your initial time frame, there is still nothing to prevent you from entering the y end again. Only this time, you will be entering the y end when it is less than a year old, and you will emerge from the stationary end when it is less than a year old. Thus you will have traveled back to a time prior to your first trip through the wormhole.

This would seem to provide a way of changing the past, except for the fact that it does not logically imply that the past will be changed. The mathmatics of wormhole interactions demonstrate that for any complex particle interchange across the event horizon (and I believe that a human jumping through still qualifies) there exists a self consistent solution such that the past is not changed (to be more precise, the 'independent' or 'origin' particle interchange is consistent, so it is only your past, or that part of it that you remember, that is unchanged).

In less wordy terms, no matter how you set up the "time machine" you cannot 'force' a paradox, there is always a way for the universe to resolve things so that the person that travel back in time doesn't change his or her (or both, as the case may be) past.

Assuming for the moment that we are simply talking about a single person experiencing more than one stream of consciousness, I can think of a number of perfectly respectable SF conventions that allow this. Telepathy, for instance, is often just such a device. Or the possibility of cybernetically integrated persons (an idea much older than the "Borg" of Star Trek fame) can be invoked. If you like, then some type of duplication technology (possibly an offshoot of matter transmission technology) could result in the duplicates of a single person having limited telepathy amongst themselves. If you dislike the idea of telepathy even in this context, then I suppose that you will have to resort to the cybernetic communication.

Term undefined, no assignment, or improper parsing error.

I'll do my best to answer

I assume that by Time Continuum you mean the extension of a single event stream from the past to the future, such that any given waveform can be defined for any given 'point' in time (I here use the term point for a specification of the dimensional value of t independent of any other dimensional values, much as a point existing on a one dimensional line or two dimensional plane is often specified without reference to any other dimensions) within the limitations of quantum indeterminacy.

Which is to say, there is one past, and it cannot be altered by an event in the present.

I am sorry to say that there is no scientific proof at the present time for such a hypothesis. While mathmaticians have demonstrated that there is always a self consistent solution for a particle/wave (or complex of the same, such as a person) traveling through a wormhole to a prior point in time, they have not yet proved that the self-consistent solution is implicit, only that it always exists.

And the first time travel mechanism I discussed is even worse. As Cosmi pointed out, 'time' flowing backwards would not be perfectly symmetrical to 'time' flowing forwards, so that if you tried to go back in time by causing 'time' to go in reverse, you would not even go back to your own past, but rather a 'past' consistent with the 'present' moment from which you initiated the 'time' reversal. Now, (as you might have guessed from all those little quotation marks) I think that this form of reversal isn't really "time" travel, properly speaking. After all, in order to travel 'back in time' using this approach, you have to have someplace where time is not going backward, but forward. Therefore, I would characterize this approach as "inverting" the laws of physics such that physics worked "backwards" rather than reversing time.

To use a rather silly and simplistic analogy, you can make your car go backwards by throwing it into reverse, but that doesn't make time go backwards. I think that the same is true of the universe...you (well, someone powerful enough) could make everything happen backwards, but since they would have to "invert" the fundamental constants to do so, I think that couldn't be considered to be actual travel backwards in time (particularly since, as Cosmi has already pointed out, because of the lack of symmetry this reversal wouldn't lead to the universe returning to a previous configuration (or 'past'), but only to one logically consistent with the moment from which the "inversion" took effect.

Which is to say that it is possible that we could consider this sort of 'time travel'to be perfectly consistent with a Time Continuum. In fact, because this sort of 'time' travel cannot generate a paradox anymore than you could by putting your car in reverse or running backwards, I would tend to posit that it cannot cause any given waveform to become undefined for any given value of t.

JK, you may still not understand the meaning of my handle. Go here for a hint.

Now then, I have a question...and I don't want to start yet another thread to ask it...hmmm.

Okay, since we cannot positively exclude time travel at this point in time, nor can we positively exclude alteration of the past, even leading to apparent paradox...I would ask,

What if you could go back in time? Would you? What if you could change the past? Is there anything that you would change? What?

Personally, I'd go back in time and tear up my 403(b) application before I invested in Enron.

The one Cosmi described is "All You Zombies" published in FANTASY AND SCIENCE FICTION IN March 1959.

So, you're right, Doc, and I was wrong.

Kathleen, I prefer to think of myself as providing helpful information, rather than making you check.

Anyone ever read those Thingamummy Hall stories? I liked some of the ideas in that, creating a sealed of universe composed of the same space at different thousand year periods, terraforming extra-solar planetary systems, recruiting a vast organization of select individuals that wouldn't get a fair shake in the time they came from...all good ideas, in my book, but why stop there?

One thing that I don't think I would personally try is saving suicides from the past and trying to integrate them into a futuristic society (a story called The Golden Halls of Hell was based on this idea, and while in the story it wasn't as bad an idea as the title makes it sound, I had more sympathy with the character that provided the title than the main protagonist)...I also don't think that it would be a very good idea to go back and enslave people in the past, like in so many stories that I forget.

One thing that time travel would make possible is effective FTL travel, since you could simply go near lightspeed for some distance, travel into the past, and then complete your journey. You could even complete your journey before you started it without causing a paradox, as long as you kept within the limitations of your destination's light event radius. Of course, that has nothing to do with changing the past, but it's still a pretty nifty idea, don't you think? On the down side, if you are using wormholes to travel in time, you could just as easily use them to travel in space without the exercise.

Native Americans are generaly those in N. America.

I used the term "Native Americans" because it generally has a broader interpretation. I think either is correct.

I don't profess to have either the scientific knowledge nor infallible intellect to make this solution to the problem that's a gnat's bite on my earlobe, but here goes.

I'm going way, way back in time, so to speak, to JK's wonderful little story about Bob. (Jan 3)

JK, (and this is for you too Shawn, since apparently you have been exploring this idea in Medicine Man... the rest of which I'm anxiously anticipating getting my mitts on... ), there was one thing that bothered me about Bob's little quest, which spurned an idea about the paradox theory on why you can't meet yourself from the past. (I'm gonna make the foray into SF just to further develop all these wonderful ideas that are floating around)

You had Bob1 leaving a note for Bob2 to go back in time to get milk at 18:00. This seems to create the loop/paradox, at least for me.

For argument's sake, let's say that Bob1 knows nothing about the milk in question prior to going back to retrieve it. He goes back, gets the milk, leaves the message and returns to 18:00. Everything seems to be going along ok to this point, but there occurs a paradox. Bob2 has interacted with Bob1, by reading the letter. All of a sudden you have split the relative timelines of Bob1 and Bob2, and there is no guarantee that when Bob2 gets to 18:00 and goes to get milk, that he will do things exactly the same, because he'll always be wondering how Bob1 is going back in His reality. You will in effect have Cloned Bob, from the point where he reads the letter. Even if the letter is left anonymously, the only way to avoid that cloning would be if the note was ALWAYS there, and Bob1, has a recollection of that strange message in the firstplace, not knowing the significance of it until he gets to 18:00. There's your loop. Of course then you get into a chicken/egg dilemma that will leave the audiences wondering, "Where the heck did the original letter come from?"

Here I propose another alternative to the Bob dilemma...
Don't leave the note!
Why?
Ok, let's take a different viewpoint on the time theory... For any person, time travels ever forward, in a line from birth to death.
Here then becomes our Bob scenario.
18:00, Bob(there is only ever 1 Bob now.) goes back in time to 16:00, buys his milk, and makes a bee line back to 18:00, where he makes his tea.
Past Bob has no contact with Future Bob, and goes happily on from 16:00 to 18:00 washing the car or whatever, and at precisely the same point when he's about to have his tea, he's reached the same decision to go back in time and get milk. Here you avoid the paradox. (sounds like Back to the Future I guess, but let's take it further)
The tension for this story then becomes Bob's quest to avoid himself, whenever he goes back in time to get things he's forgotten. Say next he realises at 18:30 that he should have gotten the groceries for his dinner as well. He'd have to try a different store, or different day, else create a paradox for the staff who see him. (any of this assumes that for other people's realities, his interaction has no effect on their timelines, otherwise we'd be back to square 1 - in truth I see no way out of that paradox regardless).
But the result is that we have a Bob who, because of so much time travelling is getting older, (because of his relative time line), before his time (as apparent to the not timetravelling folk), and is a monumentally good scheduler in space and time!!!

O-------------kay,
Time to give the old mind a rest, and not think of paradoxes for a while...
(grin)

In the Back to the Future scenario, Bob would have to deal with whatever actions he made in the past. Running into himself may create a paradox, leading him to never want to travel back in time in the first place, thus making it so he never did travel in time. But, of course, this resets everything to the point where he wants to travel again - creating a loop. But any situation may cause inadvertant interaction. If Bob bought milk, for instance, and carried it to the future with him - might not someone an hour after he bought that milk go to the same store and find all the milk sold? That person would then have no milk, and the future would be altered - maybe this person got in a car and drove angrily home, crashing into the Bob of the past on the way (creating a paradox again, because he then would never have traveled back in time, having been in an accident and not being really concerned with milk).

Traveling backward in time with the BttF model is very dangerous, as there are an infinite number of factors which could create paradox (which they portrayed in the movie, but with license, as Marty didn't instantly disappear when things were changed, but things started to slowly fade... for the plot's sake, giving him a chance to rectify the problem). The farther back you go the more of a ripple effect you can have, so that bumping into a random stranger 100 years ago might delay your father from meeting your mother by a month (or prevent it altogether)... and even the tiniest deviation might cause a different sperm to impregnate the egg that would eventually become Bob - thus creating a slightly different Bob.

Very dangerous going backward. But forward is fine, since you're not disrupting your own timeline.

The Sliders model solves a lot of these problems. There are an infinite number of "present day" realities, each following a different path through time. Every decision or option, from whether or not Bob buys milk to whether the US wins World War 2, creates an alternate path, and an alternate future.

Apply this to Bob. Bob 1 at 18:00 decides to go back along his time stream to 16:00 to buy milk and place it in the fridge. As soon as he touches down at 16:00 he creates an alternate future. The path he traveled from had no such occurence, but the path he created has a new agent (an agent whose intent is only to buy milk, but who inadvertantly changes the course of an infinite number of lives, simply by interacting with people, animals, and air particles even). Bob 2 is not Bob 1's former self, but a new version of Bob entirely, traveling along a new temporal path.

When this Bob 2 comes home and finds milk, he reacts (whether there was a note or not) differently than Bob 1 had in his own past when he opened the fridge. He doesn't travel back in time, because he has no need.

Now, this brings us back to Bob 1. Unless he can somehow hop back to the original timeline that he came from (in effect, traveling to a parallel dimension, not through time) he is trapped in this new timeline he created for Bob 2.

If he travels to the future, to the exact moment he left, he will find Bob 2 existing in that timeline along with him, because this Bob 2 never left his slot in the timeline vacant to travel back and get milk. The vacant slot is along Bob 1's original timeline, which he corrupted when he added a new factor along to its past.

Now, he can interact with Bob 2, with only psychological effects. But, this would create another timeline entirely. His decision, whether to interact or no, creates two possible futures for Bob 2. Bob 2a never interacts and lives a life somehow without knowledge of Bob 1's presence. Bob 2b interacts with Bob 1. Thus, there is another timeline split.

Unless you can hop between parallel realities (as they did in Sliders), between a present where Bob travelled and one where he didn't, or between a present where Japan bombed Pearl Harbor and a present where they were repelled by US forces, you can't return to your point of origin if you travel backward in time.

No paradoxes, no collapse of the time stream. Just Bob 1 being trapped in Bob 2's timeline.

Now, if you really want to screw things up, have Bob 2 go back in time at some point, creating a new timeline altogether. So now there'd be Bob 1, Bob 2, and Bob 3 in the mix.

Of course, there's a third construct for time, as portrayed in Heinlein's All You Zombies. Time is predestined. If you go back and meet yourself, you'll only appear as someone you yourself already had met - but a person you hadn't realized was yourself at the time. Go back and talk to yourself at 6 years old, and suddenly you put two and two together and realize that strange man who talked to you when you were 6 was actually you! (Like Harry Potter and the Prizoner of Azkhaban... the whole "Harry thought it was his father, but it was really him travelled back in time" philosophy).

This third construct is also kinda what they used in 12 Monkeys, though it only worked with very sparse information from the past. They conducted the travel to answer questions about the present, but in so doing created the questions they sought to answer. Predestined time. The present exists because of some destined interaction the future will have with the past. (For a fantastic example of this, read "Go Toward the Light" by Harlan Ellison, in his Slippage collection of stories)

I love all the theories - there's so much to mine for story ideas. I'm sure there are more, but those three are definitely distinct in themselves.

Just my two cents.

Cow

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If you destroy the univers with impossibility, the gods of fate will kick you out of existance. --- The Great Path of Play

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