October 3, 2012

Time Travel: Does it make for a better plot if you can or can't change history?

There are a million stories about time travel, but the good ones have to choose a side: when you go back into the past, either you can change the present or you can't. I'm not an expert on science fiction, but in my mind the canonical stories illustrating these polar opposite theories are one by Ray Bradbury and two by Robert Heinlein.

Bradbury's 1952 story "The Sound of Thunder" about a tourist who goes back to the dinosaur age and steps on a butterfly, making the present much worse when he gets home, is the source of the term "butterfly effect" about how small changes can have big results.

In contrast, Heinlein's 1941 time travel story "By His Bootstraps" is a good introduction to the paradoxes of predestination in which the time travel all unfolds as fated despite the best character's best efforts to change the past. 

Heinlein returned to this notion in 1958 in one of the last short stories he wrote, the crazy, solipsistic "--All You Zombies--". Heinlein's character ultimately reflects:
Then I glanced at the ring on my finger. 
The Snake That Eats Its Own Tail, Forever and Ever. I know where I came from - but where did all you zombies come from? 
I felt a headache coming on, but a headache powder is one thing I do not take. I did once - and you all went away. 
So I crawled into bed and whistled out the light. 
You aren't really there at all. There isn't anybody but me - Jane - here alone in the dark. 
I miss you dreadfully!

That's one of the weirdest endings ever. (That reminds me of all the cults that were forming at the time around around lesser sci-fi writers, such as L. Ron Hubbard and Ayn Rand. There was something in the air in the run-up to the Sixties. It speaks to Heinlein's strength of character and/or short attention span that, despite his tendency toward solipsism that runs amok in 1961's Stranger in a Strange Land, he was less tempted than they were to give in to being a cult leader. Heinlein had the ego, but not the capacity for boredom.)

So, which theory of time travel makes for better stories? 

Back to the Future sides with Bradbury, and that's a pretty good movie. 

On the other hand, you could argue that Sophocles' Oedipus Rex is a proto-time travel story that takes Heinlein's side. How does the Oracle know that Oedipus will kill his father and marry his mother? Maybe she has a time machine! 

And that plot works pretty well, too.

I was thinking that maybe Bradbury's changeable history makes for better comedy and Heinlein's deterministic history makes for better tragedy, but perhaps the opposite is true. The gyrations that a Heinleinian time travel plot has to go through to make everything wind up being the same are often exhilaratingly comic, while Bradburyesque plots like the new Looper, which takes a strong stand at the end in favor of [Spoiler Alert!] mother love, often tend toward the sentimental.

74 comments:

Beefy Levinson said...

I'm of the opinion that if time travel into the past were possible, you could not change the present. The 2002 version of "The Time Machine" explains it nicy through Jeremy Irons's Morlock character: 1) The inventor made the time machine to save his fiancee's life; 2) but if he saved her life, he'd never have invented his time machine in the first place; 3) so if he saved her from getting shot by a mugger, she'd die in a car crash or something else instead.

Of course that doesn't mean you can't write a good story from the opposite position either, i.e. that you can change the present. Basically, you'd have to accept the multiverse theory. When Biff changed the present, for example? Makes you wonder what happened to all the people in that timeline when Doc and Marty erased it.

Anonymous said...

I want to go back in time!

Cail Corishev said...

The Hitchhiker's Guide to the Galaxy is a good example of the "you can't change it" type. At one point, Arthur realizes he can't die because something he knows he's going to do hasn't happened yet.

Star Trek did about a hundred time travel stories, and generally went on the Back to the Future model, except when it didn't.

I think the "you can change it" model makes it a lot easier to tell a story, but it also introduces impossible paradoxes or pointless cheats like multiple timelines. Saying that you can't change things makes a lot more sense, but is limiting plot-wise. Hitchhiker's is pretty impressive the way it ties all the different times and events together without contradictions.

sconzey said...

There is a middle way exemplified by a couple of stories: in 'Timescape' a physicist sends messages to his past self by interfering in an experiment he was doing in the 70s with the intent of avoiding an impending natural disaster. He is able to change the present in limited ways by e.g. his past self putting things in a safe deposit box to send them forward, but is unable to avert the natural disaster in his own timeline.

Harry Potter and the Methods Of Rationality has my favourite portrayal of time travel, being the most highly specified. The TSPE arc involves a lot of time travel and is deliciously mind-bending. In that, you can use time travel to influence future events, but only those which you have not yet observed the outcome of.

Anonymous said...

Asimov's "The end of eternity" was a pretty cool take on changing the future. The Time Police patrolled the corridors of time to unwind unauthorised changes. The far future was out of bounds, presumably because the inhabitants didn't want to get affected.

But I read it as a teenager in the Sixties, so I probably didn't think the paradoxes through too deeply.

wren said...

South Park has dealt intelligently with time travel on many occasions.

In one episode it is explained nicely as "Terminator Rules," "Back to the Future Rules," or "Timerider Rules."

Anyway, parallel universes allow for all possibilities. As we all know.

HerewardMW said...

Asimov's science fiction short story "The Red Queens Race" was about exactly this.

The title is from Lewis Carroll, obviously, and likens time travel to the race where "it takes all the running you can do, to keep in the same place".

commentor said...

I thought the butterfly effect was born out of the science of chaos theory and strange attractors. Namely that a tiny change to the input conditions at time A can result in a very different system state at time B.

I'm surprised no pedant has posted about this yet.

commentor said...

I thought the butterfly effect was born out of the science of chaos theory and strange attractors. Namely that a tiny change to the input conditions at time A can result in a very different system state at time B.

I'm surprised no pedant has posted about this yet.

neil craig said...

In reality (if the term has meaning) the Everet multiple universe thoery (that every possible action happens and creates a new universe) solves the paradox. Though it produces new ones, it seems to be genearlly accepted now by those who study quantum effects and astronomers who study the largest subject.

Artistically an unchangable universe can only be a field for tragedy, something the Greeks were good at.

On the other hand for any sort of continuing drama a changeable universe tends to discredit the basic bible - almost all Star trek plots could be ended just by going back in time to before the action started - that even includes the time travel plots.

Anonymous said...

How does the Oracle know that Oedipus will kill his father and marry his mother?

A little off-topic, but does Sophocles ever state the ages of the characters?

I don't see how the story works unless maybe Jocasta is about 13/14/15 years old when she gives birth, so that when they are re-acquainted many years later, Oedipus is maybe 18/19/20-ish, and she, at 31/32/33-ish, is still sufficiently teh flaming hawtness to be the object of his carnal desire.

But if you fast forward several thousand years, to our era, then she's gonna be an early-40s aging feminazi spinster, living all alone with her cats, who decides to go to the sperm bank for a baby [or who pulls a very brief Stanley Dunham fling with a negro], and Oedipus is gonna be in his mid- to late-30s before he's gonna wanna quit playing the field and settle down, so she could be almost EIGHTY before they're re-acquainted.

And before you charge me with exagerating the problem, Chelsea Clinton is 32 and married with no children, Kate Middleton is 30 and married with no children, Jenna Bush is 30 and married with no children, and her twin sister, Barbara, is still single.

PS: Apparently Oedipus & Jocasta had FOUR CHILDREN after they were married, so she must have been not much older than her early thirties when they were re-acquainted.

Marlowe said...

Asimov's The End of Eternity also exemplifies a strong aspect of time travel fiction: paranoia. How do you know the past is the real past and not the product of tampering? The dictum of The Party in Orwell's 1984, Who controls the past controls the future; who controls the present controls the past, becomes a practical process. In Oceania, The Party did it all on the cheap - by simply altering the records of the past to make it look like their preferred version happened. But if you can go back in time you can make it happen. In Asimov's story it results quite logically in a stultifying regime of control.

Marlowe said...

All regimes predicated on absolute control result in solipsism for the controller and paranoia for the controlled.

Anonymous said...

There are several view of time. The only thing that bothers me is when a sci-fi plot makes use of several conflicting theories. Star trek and Star gate both did that "change the future and the parallell universes thing. You can have one or the other, but not both.

Another thing they don't delve too deeply into : if there are infinite parrallell universes, then teh value of teh unique idnividual and the unique historical outcome is irrelevant since all the outcomes good and bad eventually happen anyway, somewhere. And the value of human life diminishes, approaching zero since every human life is infinitely replacable with an exact copy.

Anonymous Said said...

Alfred Bester's "The men who murdered Muhammed" has timeless appeal.

Anonymous said...

"Maybe Jocasta is about 13/14/15 years old when she gives birth"

In Classical times, Greek women married in their early teens, so these ages are plausible. If Oedipus was 16-18, he could marry her when she was around 30 with plenty of time for four kids.

Cennbeorc

Anonymous said...

you can't change time "from the inside" :)

Anonymous said...

http://www.foreignaffairs.com/articles/138162/daniela-schwarzer-and-kai-olaf-lang/the-myth-of-german-hegemony

j mct said...

Time travel into the future is easy, one just hibernates in some sort of way. Time travel in the past is a bit different though, and you're dancing around some effects of the obvious stuff.

Married bachelors are logically impossible, in that it's something that one can say, but it's not something that someone can think. A clean shaven barber of seville who shaves all and only the men who do not shave themselves is also logically impossible, but it's not as obvious that it is as the married bachelor. Time travel is as logically impossible as a final digit of the square root of two, but it's not as obvious, so there are stories about it, that lead to the paradoxes.

Part of the definition of 'past' is 'cannot be changed'. Just traveling there would change it, so...

Last but not least, the laws of physics say it's impossible, though there isn't anything built into math saying it should be so, but it is odd how it turned out that way.

Anonymous said...

The most amusing (to a SF fan) essay I have read on science-fictional time travel is Justin B Rye's "SF Chronophysics" here:

http://www.xibalba.demon.co.uk/jbr/chrono.html

Anonymous said...

If I were an Syrian or Arab and could go back in time, I would abduct around 20 Jewish geniuses--Isaac Cumstein, Moishe Cummowicz, Bernard Cumfeld, etc--and take them back to Syria 100 yrs ago. And I would make them impregnate a 1000 Arab women each. Then, the elite IQ of Syria would be much higher, and Syria would be at the forefront of scientific and technological innovation.

Project Schwarz could transform the Middle East.

Anonymous said...

If I could go back to 1999, I would show the result of Bush II presidency to GOP bigshots and tell them, DON'T GO WITH THE DUMBASS.

Anonymous said...

If I could back to the 1980s, I would tell Reagan not to do amnesty.

Anonymous said...

If I could go back to 1988, I would tell Bush not to go with Quayle dumbass as VP.

Anonymous said...

If I could go back to 1992, I would tell Buchanan to tone down his convention speech.

I would say, 'red meat is fine, but look, you gotta play smart. media are controlled by Jews, libs, and gays, and if you go too hard, they're gonna slam you and smear the entire GOP as the party of eviloids. So, even as you oppose the gay agenda, don't dehumanize gays. Even as you stand up for workers in Oregon and Washington and oppose radical environmentalism, say something good about the need to protect nature. Be more balanced. Otherwise, the media will demagogue your speech just like you demagogued key issues. The fact is media got lot more power than you do."

Beefy Levinson said...

There's a Star Trek series about the Department of Temporal Investigations. Going insane is a major on the job hazard for that very reason: agents conclude that if there's an infinite number of universes, then it doesn't matter what they do. They end by shooting everything in sight.

Pat Boyle said...

It doesn't really matter which of these choices or any of the many other variants that the writer employs as long as he (women can't write Science Fiction) takes the time to establish his premises and remains consistent.

Asimov once pointed out a problem with SciFi detective stories. The classic murder in the sealed room plot doesn't work if the villain can enter the room through the fifth dimension. Drama and tension come from characters working against constraints. Sci-Fi story assumptions mustn't be too free.

This is what's wrong with the writing of series TV. The writers just throw in whatever assumption like time travel they think of. Its promiscuous plotting. It's too easy. Really good Sci-Fi should be a struggle for the writer.

BTW there are several other related time travel tricks. Obviously Bill Murray is stuck in a one day time travel loop in "Groundhog Day". In the Director's cut they show how he had been abducted by aliens for his routine anal probe and the Greys decided to play a trick on him.

See what I mean about writers needing plot discipline?

Another kind of soft-core time travel plot is Tom Cruise's Hitler assassination movie "Valkyrie". When you make such a movie you know that everyone in the audience has fantasized about having a time machine and going back to kill Hitler. The writer doesn't have to explicitly introduce a time machine. The audience supplies that device for themselves.

Albertosaurus

Anonymous said...

LA JETTE is the only truly great work of art about time travel, but then it could all have been a hallucination.

Anonymous said...

MEMENTO isn't a time travel movie but it sort of feels like it cuz the character is trapped in INSTANT TIME.

Chad Brooks said...

Poul Anderson had great fun with time travel. He was especially good at the pivotal point change story. In his universe(s) most effects are dampened out but sometimes, somewheres time could be changed. And his characters do deal with the issue of if I change time who am I eliminating. Highly recommend his books for those who are interested in time paradoxes.

Anonymous said...

ESCAPE FROM THE PLANET OF THE APES has an interesting time travel scenario. Should the ape couple be killed in order to save mankind from being enslaved by apes?
And it's rather intelligently handled. Even the villain has a point.
It's a weird experience because we rationally agree with the guy who decides to kill the ape kid but emotionally we side with the ape couple. We feel torn.

Anonymous said...

There is one kind of time travel that is real. If you travel really fast, you age slower.

Though Noriko character of GUNBUSTER is a pain in the ass, GUNBUSTER has one of the most moving treatments of time travel's relation to emotions/meaning/friendship.
Especially the final two episodes(out of six) are deeply moving as Noriko stays young while traveling near light speed in outerspace while her friends grow old.
And the final 5 minutes of the series is just devastating. 11,000 yrs!!!

(Remake of Gunbuster is sucky. The original is what counts. Too bad silly Noriko is the lead character. Jung Freud and Amano should have been the leads. Gunbuster is like Starship Troopers, but much better.)

http://www.youtube.com/watch?v=z6ftfD0b8wQ&feature=related

A.I. isn't about time travel technology, but the robot kid does travel through time since robots have been built to last forever. And the final segment is maybe the most moving stuff I've ever seen.

MINORITY REPORT also plays on time travel ideas. It's about telepathic time travel, and though some of the action is too much and some of the emotions are overwrought, it is still a superior scifi flick.

And I think all these movies have a lot to do with IDENTITY, so I disagree with Sailer's comment that sci-fi is about gadgets while superhero is about identity.
What is LA JETTE but about identity? And BLADE RUNNER's emotional power comes from the theme of identity. What is human, what is artificial?

Anonymous said...

Alfred Bester's "The men who murdered Muhammed" has timeless appeal.

Timeless appeal - very good. Lol!

stari_momak said...

CS Lewis has a story where the protagonist goes back in time. Even walking on grass is difficult for him, because Lewis starts with the proposition that you can't change history, and therefore even the blades of grass you step on can't bend in response. I'm sure there is some sort of theological message there, but I can't recall what it is.

BTW CS Lewis's science fiction was quite good. I've always thought that 'Out of the Silent Planet' would make a great film.

Anonymous said...

Given that time travel were possible and historic meddling permitted, then I think Bradbury wins hands down. However, his timeline is way off. You don't have to go back 300 million years in order to see big results in the present. Consider the popular fantasy of going back in time to kill Hitler and thus save 6 million Scots/Irish from certain doom. That would mean that 10s of millions of men would not have died. The Industry of the free world would not have been mobilized for war, the great depression would have continued, etc. etc. The cascading effect of all that change would be that the chance of the coming together of the unique combination of sperm and egg that makes you a specific person would be infinitely diminished. Thus, granted there would still be billions of people, almost the entire population of the world born after 1945 would be completely different. That means the time traveling assassin would be committing suicide, as well as effective killing billions of people who already exist. And there is your paradox. Would it be considered suicide/murder by making billions of people not exist? After all, we do exist in this timeline. Perhaps a syllogism is in order.
If Hitler murdering time travel is possible then Many Worlds exists. (Or whatever, I'm not a logician) If it didn't the time traveler wouldn’t be born.., etc.

Anonymous said...

The only thing that bothers me is when a sci-fi plot makes use of several conflicting theories. Star trek and Star gate both did that "change the future and the parallell universes thing. You can have one or the other, but not both.



The idea is that you can have both, in different regions of space-time. Star Trek also features a third possibility, that of loops in time where everything is repeated endlessly. Groundhog Day is another example of time being stuck in a loop, though it's not considered a sci-fi movie.

Matt said...

Whichever time travel version you do, you have to commit to it. J.K. Rowling hilariously wrote herself into a corner in one of the Harry Potter books by having Harry & Co. save the day with a time-travel device which is so easy and common that it's given to a child to help her take more credit hours at school.

When Rowling realized in the next book that this completely destroys the possibility of suspense, she basically says "Oh yeah, and all the time machines were on one shelf and somebody knocked them over and broke them."

Anonymous said...

Steve, you've missed your calling as a university English professor. That post has "five page response, minimum, double spaced, due by Friday of next week" written all over it.

Anonymous said...

Time travel stories generally are about those doing the time traveling and time-changing.
How about stories about people for whom their world has been changed by those who did the time travel/changing.

Suppose you're a girl in love with this guy. He means so much to you. But one day you wake up and realize he doesn't exist anymore. Indeed, you learn he never existed, and no one knows him. There is no evidence of him.
How could it be?
Suppose someone traveled back in time and prevented his parents from meeting, and so the guy was not born.

Now, the hole in this plot is IF THE GUY WAS NOT BORN, THEN YOUR MEMORY OF HIM WOULD HAVE BEEN ERASED TOO. But suppose your memory of him survived through some wormhole, and so you are the only person who knows that person.

Anonymous said...

WICKER PARK is kinda sci-fi feeling-like. By some trick pulled by a third party, the 'time' between the two lovers got all messed up.
And because the guy is in Chicago when he should be in China--indeed his boss and girlfriend thinks he's in China--, it's like he's slipped through some kind of time warp.
A moment can change an entire life.

Anonymous said...

ONCE UPON A TIME IN AMERICA is like time travel, at least psychologically. The train station and the hole in the washroom wall at Fat Moe's are like portals to another time. The opium den too.

Auntie Analogue said...



"Time waits for no one, and it won't wait for me."

Anonymous said...

Pedant to the rescue!!!

http://en.wikipedia.org/wiki/Butterfly_effect

"The name of the effect, coined by Edward Lorenz, is derived from the theoretical example of a hurricane's formation being contingent on whether or not a distant butterfly had flapped its wings several weeks before."

Anonymous said...

I think the whole argument of can/can't change history is moot.

If someone, who should NOT be in a certain period, appears in there history has ALREADY changed.

For a reason I never understood, some writers feel it is their duty to 'maintain the status quo' and prevent the characters from doing anything to change wherever the author is at now.

I don't feel that way. Even if the character does nothing but breathe even once before coming back, the character's breath contains pathogens which were unknown at that time,potentially creating an epidemic which changes history.

Once the 'change' is made, it will ricochet in a direction the author can't manage. Period.

Anonymous said...

Once the time travel took place, CHANGE already occurred.

You can't put a genie which came out back to the lamp. Even if you somehow did, the genie already had his footprint all over, changing history.

agnostic said...

"Sound of Thunder" and "All You Zombies" are also cool song titles from Duran Duran and the Hooters. Seems like literary references in pop music used to be to less obvious sources. Echo and the Bunnymen wrote a song about John Webster called "White Devil," not one about Shakespeare or Marlowe.

It seems like more recent examples are more self-conscious and obvious to make sure the audience gets that they're singling out some VIP.

Anonymous said...

"The good ones have to choose a side: when you go back into the past, either you can change the present or you can't."

There is third type where the story cares not a whit about present. Time travel is usually just an excuse to send characters from the modern time to the author's favorite historical period. Such stories are often exercises in nostalgia for the past. Jack Finney's Time and Again is typical of a book like this.

Anonymous said...

"The 2002 version of "The Time Machine" explains it nicy through Jeremy Irons's Morlock character:" - We never saw him attempt to take her into his future. If that works then he saves her, doesn't really change the past, and still has the incentive to build the time machine.

Anonymous said...

No one had more mastery of telling great time travel stories than Isaac Asimov.

The way I understand it "The Butterfly Effect" can refer to a ripple effect without time travel (a butterfly flapping its wings in China results in a tornado in Kansas) or with respect to time travel, killing a butterfly a million years in the past irrevocably changes the present.

Cail Corishev said...

"[T]he Everet multiple universe thoery seems to be generally accepted now by those who study quantum effects and astronomers who study the largest subject."

Are these real quantum scientists, or the kind who appeared in the movie The Secret, which said if I just visualize a winning lottery ticket strongly enough I'll get one?

Marlowe said...

It's probably worth mentioning that Willis starred in an earlier time travel flick, Twelve Monkeys, and it took the immutable past principle as its premise. The bald yin wanders around the pre-apocalypse world explaining how he has come from the depopulated grim future after a world destroying plague and answers the obvious query about whether he has come to stop the end of the world by repeatedly stating that he hasn't because you can't change the past.

Anonymous said...

Who was it that said America is like a big ship headed towards a giant iceberg, what with all the looming deficits, changing demographics, out of control spending, and out of control globalism?
The way we are headed, we are sure to hit the giant iceberg and sink--like much of Europe is doing.
And in order to avoid hitting the ice berg, we need to slowly steer the ship away from the direction of the iceberg. Because our ship is so big, we cannot change its course right away. A big ship like ours isn't like a rowboat that can be swerved this way or that way.
A big ship's direction can only be changed gradually due to its size and momentum. And if we gradually shift the direction, we may avoid hitting the ice berg--though we'll still hit a lot of smaller ice chunks around the iceberg.
This is what conservatives should be saying.
The problem with Ron Paul and Peter Schiff--for many people at least--is they wanna fully/instantly steer the ship in another direction, but the danger is the ship might tip over with such a sudden turn--and people on the ship will be tossed all about.

Romney should have made this case, but he didn't. He should have used the metaphor of the iceberg, warn of looming deficits, and say he wants to steer the ship gradually to avoid hitting the big ice. And to do this, he should say he'd gradually cut spending but also increase taxes on the rich that profited so handsomely from globalism. But NOPE!

little dynamo said...

often you write informatively about subjects within your ken

why write about stuff you dont understand?

ditto for Professor Hell

everybody in the modern world has to be an Expert on Everything, even the stuff about which you havent a clue!

lol

Svigor said...

I like the Marvel Comics multiverse approach, which gives you both; you can't actually time-travel, only travel to alternate universes that seem like points in your timeline. All the great taste of time travel, with none of that funky paradoxical/nonsensical aftertaste.

alonzo portfolio said...

The obvious time-travel hook would be to land modern, entitled and self-obsessed teens in a 1940's schoolroom where nobody takes any shit from them. Now that would be comedy!

elvisnixon.com said...

The best of any recent(2007)time travel films is the Spanish "TimeCrimes" (or Los Cronocrimenes for Southern Californians)

Both possibilities are explored as well as the paradox of participating in ones own past/future.

Strongly recommend for plot and absolutely unique cinematography/set design

Simon in London said...

The original Terminator movie seems to take an everything-was-predestined approach, and it is a pretty strong movie, certainly up there with Back to the Future.

The Chaotic nature of the Bradbury universe fits much closer to what we know of Real Life - that our very existence is due to a heap of improbable coincidences. The chain of unlikely happenings that caused me to meet my wife; the chain of freak occurrences that caused my son to be who he is. And the same for every human on Earth. I don't think people can deal with that too well, though. We much prefer Fate.

Melendwyr said...

Unalterable time makes more sense, logically, but people seem to find alterable time stories more entertaining.

Possibly because such stories usually draw on a narrative model of time things that happened in the beginning of the story can't be changed, but a "past" that occurs in the future of the story itself can be alterable. Back to the Future is an excellent example of this - everything encountered in the 1950's is supposedly 'past', but it's the present of the story, and the 'past' events which have yet to occur in the story of the movie can be altered. Just as the 'present' which is at the end of the movie is altered by the previous events.

Anonymous said...

How could anyone consider this topic without pondering Nietzsche's eternal reoccurence?

His metaphysics are remarkably congruent with that of modern Americans. Materialism. Everything is atoms bouncing off one another and everything follows causality. Different "times" are merely different arrangements of atoms, caused by the prior arrangements. If you want to go back to yesterday you only need to arrange all the atoms in the universe as they were yesterday. Of course that means all your atoms have to be exactly as they were yesterday so you become yourself of yesterday with the knowledge of yesterday the motives of yesterday (thoughts being merely an arrangement of atoms in the brain).

This view sort of kills the dramatic potential of time travel fiction. Of course he said, live as if you would have to relive every moment of your life repeated through eternity.


Geoff Matthews said...

Loved 12 Monkeys. The idea of time travel with it worked well.

How do you get around the idea of matter not being able to exist in more than one spot at the same time? I'm pretty sure that the atoms that make up my body were around before me, and will be after I die.

Geoff Matthews said...

BTW, I went back in time to warn people not to vote for Al Gore. If you thought Bush was bad . . .

georgesdelatour said...

We're on a planet orbiting around the Sun. The Sun is moving through the Local Interstellar Cloud in the Local Bubble zone, within the inner rim of the Orion Arm of the Milky Way. Astronomers believe the Milky Way is moving at approximately 630 km per second.

This means that a time machine - even if feasible - has to be a space machine as well. Otherwise it's going to kill you. If I send you back in time thirty years, but to the same co-ordinates you're currently at, I'll be sending you into deep space. I won't need a hit man to kill you, as in "Looper". The vacuum of space will kill you unaided.

Cail Corishev said...

"If someone, who should NOT be in a certain period, appears in there history has ALREADY changed."

That's kind of the point. In the Star Trek/Back to the Future concept of time travel, you can go back and change things and change your "present." But in the Hitchhiker's Guide concept, you can't: anything you do in the past was "always" done in the past, and always had whatever effect it was going to have on the present that you traveled from.

If you could step outside the timeline and look at it, it would be a completed whole, with any trips through time having had their effects on those points. Everything along the timeline happens simultaneously, sort of, so no point along the line is ever affected by any "new" events after it happens.

So in this way of looking at it, you simply can't go back and prevent your parents from meeting, because your existence proves that they did meet. If you try, you're guaranteed to fail.

Futurama was another show that did a good job of sticking to the unalterable timeline concept, except for the Roswell episode, which was really kind of a spoof.

Anonymous said...

I wanted to write a time story, and thought I had a fresh hook. It involves a time traveler who finds himself lost in space after realizing that the earth is billions of miles away from where he departed the timeline and it will take x as many years to arrive at his current spot as he went back in time. Unfortunately
(1) The idea has been kicking around in science fiction since the thirties, and
(2) apparently, the idea has been discredited by a consequence of general relativity called "diffeomorphism invariance"
unless of course, if (sniff) EINSTEIN WAS WRONG!! :o)

Glaivester said...

Futurama was another show that did a good job of sticking to the unalterable timeline concept, except for the Roswell episode, which was really kind of a spoof.

Did they actually alter anything in the Roswell episode? I remember Fry killing his grandfather and then becoming his own grandfather, but is there any reason to assume that it was not this way from the beginning?

Actually, there was an episode where they changed time - the one where the giant brains had the giant Dyson Shell - Fry went back in time and got the Nibblonians to give him a better Scooty Puff space scooter than he had had originally.

Glaivester said...

Two ideas I had for time travel stories - when you change the past, the timeline simply adjusts to some equilibrium where everything is consistent - you kill your own grandfather, the timeline readjusts so that someone else kills him, so you don't need to exist.

Alternately, any time traveling person is a soul who will exist no matter what, and if you stop yourself from being born, you simply become a different person - however, you keep your old memories. Someone actually stops his parents from meeting, and then discovers that he is a woman, who was the baby that his mother had with someone else.

Semi-Employed White Guy said...

alonzo portfolio said...

The obvious time-travel hook would be to land modern, entitled and self-obsessed teens in a 1940's schoolroom where nobody takes any shit from them. Now that would be comedy!


There was already a movie along those lines, although not technically a time travel movie. The plot of Pleasantville has modern teens getting stuck in a 50s sitcom. I didn't see the movie, but I think it portrayed the people from the 50s as boring, uptight (white) and that they needed to be more like the hip, modern kids (black). Just what you'd expect from Hollyweird. That's why I never bothered to actually watch it.

Anonymous said...

"How do you get around the idea of matter not being able to exist in more than one spot at the same time? I'm pretty sure that the atoms that make up my body were around before me, and will be after I die." - There is really no reason why duplicate copies of the same atom, wouldn't work like two similar atoms, and it probably wouldn't matter anyway. If you ate a burger that your mom would have eaten when she was pregnant, she'd just get a different one.

Anthony said...

Larry Niven addressed this in his essay The Theory and Practice of Time Travel. He formulated Niven's Law: "If the universe of discourse permits the possibility of time travel and of changing the past, then no time machine will be invented in that universe." The reasoning is that time machines will continue to be invented, and used to change the past, until some change occurs such that no time machine is ever invented in that universe.

Glaivester said...

I remember Fry killing his grandfather and then becoming his own grandfather, but is there any reason to assume that it was not this way from the beginning?

To be more precise, maybe his "grandfather" was never really his grandfather in the first place.

Mr. Anon said...

"Simon in London said...

The original Terminator movie seems to take an everything-was-predestined approach, and it is a pretty strong movie, certainly up there with Back to the Future."

Though entertaining, the Terminator movies are pretty silly. The pre-destination implied in T1 was thrown out for T2, because they needed to dispense with it to make the sequel. Then it was reintroduced in T3, because they needed it to have an ending that wasn't just a rehash of T2.

Even more silly was the nature of the time machine. In T1 - for some reason - metal could not be sent backward in time, only flesh. Unless the metal was enshrouded in flesh, then it was okay.

Well, it was just movie - really just an excuse to show Arnold rampaging through LA.

What I thought was a pretty good time-related movie, though not actually involving time travel, was "Paycheck", based - like almost every SciFi movie nowadays - on a story by Phillip K. Dick.

Anonymous said...

The best time travel fiction was presented in the early 2000s as ostensible fact, John Titor.

He postulates a theory of multiverse that is on its face the only logical one. In the multiverse, the probability of any event which is within the laws of physics to happen is one. An infinite, or effectively infinite number of timelines exist. Titors-time travelers-using a McGuffin that resembles a Howell Industries Jetcal box so strongly as to be scant coincidence-go back on one line, and return to one very similar to but never identical to the one they left, so there are always tiny but noticeable differences, such as in the typography of letters, exact dates in history, et al.

It was a hoax of course, unless of course Titor accidentally changed this tikmeline so drastically that the disasters known to have happened in his 2036 prevented or drastically delayed his description of history. But it was so well done you almost have to wonder still. (The Jetcal box was a tipoff only to those who knew what a Jetcal box is, as was the Progline era GE logo in the tech manual pages he presents.)

Anonymous said...

One strange thing about time travel is if you transported from where you sit now on earth, to the same spot in the universe 50 years ago. You would be in a vastly different part of the galaxy.

As not only is the earth moving in space, but the whole solar system is too.

My personal feeling is that the theory of relatively is wrong in regards to time. The universe does have an absolute clock. And time travel is one of the few science fiction dreams mankind has had through the ages, that will not be possible.

On the other hand age old sci-fi dreams such as human flight, horseless chariots, golems, oracles, crystal balls, windows to other places not connected are already possible and advancing.

Other dreams such as the fountain of youth, space travel, artificial intelligence I believe will be possible.

Anonymous said...

"1) The inventor made the time machine to save his fiancee's life; 2) but if he saved her life, he'd never have invented his time machine in the first place; 3) so if he saved her from getting shot by a mugger, she'd die in a car crash or something else instead."

4) Only way to save his loved one is to keep history intact, for example faking her fiancee's death. If future version of inventor thinks his fiancee is dead, he is still going to build time machine and history is not changed.

Faking death is obviously very hard, but it wourk well in accidents where bodies are disintegrated or not found at all, for example shipwreck, plane accident.