I know...most people agree with you. The main reason I think otherwise is because it makes Bruce Willis' character's story even darker; something I can easily see Terry Gilliam (my favorite director, btw) doing. But I could be wrong.

I always liked "Retroactive" ( http://www.imdb.com/title/tt0117468/ ). Every time she goes back to fix the situation it only spirals further out of control with each trip.

David.

Retroactive is hilarious. Time travel, Texas style.

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Life is like a box of chocolates. All of your choices are bad for you.

"Makes sense" is intuitive. Reality is often counterintuitive.

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"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
Illuminati's Razor-The most complicatedly evil answer is usually the most correct answer. - Fazor
"Every book is a children's book if the kid can read." - Mitch Hedberg
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort

I disagree. Quantum theory - or for that matter the behaviour of a gyroscope when you rotate its axis - is counterintuitive, but it still makes sense.

Something fails to make sense if it contradicts itself.

Well, that's a different definition of "makes sense" than I've ever heard, but anyway.

Apparent contradictions can be explained by unpresented or unexplained data; don't assume that what you see onscreen is the whole story, or that the characters' stated assumptions about how it all works are always right.

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"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
Illuminati's Razor-The most complicatedly evil answer is usually the most correct answer. - Fazor
"Every book is a children's book if the kid can read." - Mitch Hedberg
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort

ha ha, I'd say if Quantum Theory makes sense, you don't understand it! (almost a quote of someone in the early 20th century). Or the way I put it--if you think you understand Quantum Mechanics, that's proof that you don't!

Actually, we're not even sure QM is consistent--after all, the Feynman path integrals used in QM computations work, but mathematical theory doesn't explain why (it's like in the old days of Newton and Leibniz, the tricks with manipulating dx and dy in calculus worked, but it wasn't until Weierstrass that it was made rigorous).

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Todd (Bowie, MD, US, North America, Earth, Sol System, Vega region, Local Bubble, Orion arm, Milky Way Galaxy, Local Group, Virgo A Cluster, Virgo supercluster, the universe in which spock is clean shaven)

Quidquid latine dictum sit, altum sonatur.

personal page: http://blog.astrosketches.info

I'm currently reading, "The Light of Other Days" by Arthur C. Clarke and Stephen Baxter.

You can view the past, but that's it (at least so far). Consequences of that alone are strong enough that you don't need real time travel to make a story.

I think I'm one of the few who like "The Butterfly Effect". I guess that movie one could really ignore the whole time travel factor and focus on the central idea of the movie - which I found to be interesting.

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Spock Jenkins of the Vulcan Jenkins'.

It seems to me that the idea that the past can't be changed is pretty untenable. If it were, we are forced into one of two alternatives: that the "present" is somehow objectively different from any other moment in time, no matter how a time traveler experiences his local "present"; or that both the past and future are immutable, and that nothing can possibly occur differently from that which is "ordained." The first alternative seems to unreasonably differentiate "now" from "not now"; at least to me, position in time is as relative as position in space, and that no reference frame should be unduly "privileged." The second alternative, that the future is as immutable as the past, trivializes any choices and makes any sort of chance or consciousness meaningless; I have a hard time accepting that.

There are two options that I do find to be much more consistent and plausible. Branching worlds cleans everything up neatly. The other is to assume some sort of non-causal, disjointed time flow where the past and the future are not necessarily connected, and that a time traveler can come from a future that no longer exists; there can be no paradox here, but that also means that every single time a trip is made into the past, that particular time path retroactively ceases to exist from the destination point onwards, and the time traveler's "history" is meaningless.

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There really is nothing like looking at the sky while lying down in a boat in the South Pacific two hundred miles from the nearest electricity. Next time, I'll try to remember a telescope.

Let's be careful to separate fiction from known science: There is no evidence that it is possible to travel into or to change the past. For a story, of course, you can have any rules you want.

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I say there is an invisible elf in my backyard. How do you prove that I am wrong?

Disclaimer: Avatar is not an official NASA image and does not imply any specific interplanetary or interstellar capability.

The Leif Ericson Cruiser

The "unchangeable past" can make sense, though, assuming travelling into the past has the same effect as looking into the past; I.E., none from the present's point of view. The time traveler then loses the ability to change outcomes. He can make all the decisions he wants, but since they've "already" happened, it changes nothing. In this scenario, going into the past means becoming part of the past.

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"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
Illuminati's Razor-The most complicatedly evil answer is usually the most correct answer. - Fazor
"Every book is a children's book if the kid can read." - Mitch Hedberg
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort

But his "already" presupposes that his "already" is somehow privileged in relation to his his "past's" "already". (Good grief, I need a few more tenses and pronouns here.) If he is now a part of the past, what makes his history any more immutable than the present's "future."

From my point of view, assuming there are no time travelers at all, the future is mutable. Add a time traveler from (my / his) future, and suddenly my future is no longer mutable? That seems to indicate that, if time travel is possible and the past is immutable, than the future must be immutable as well.

The time traveler's knowledge of his past / my future has to become meaningless, or all possibilities have to be meaningless, as well, because there are not possibilities, only certainties.

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There really is nothing like looking at the sky while lying down in a boat in the South Pacific two hundred miles from the nearest electricity. Next time, I'll try to remember a telescope.

No, it's only immutable from the point of view of those in or from the future. To those experiencing the events for the first time, it's just like any other moment.

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"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
Illuminati's Razor-The most complicatedly evil answer is usually the most correct answer. - Fazor
"Every book is a children's book if the kid can read." - Mitch Hedberg
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort

Then someone experiencing events for the first time is able to alter events so that the "future" is different than the traveler expects? If no, then it's not really mutable, is it?

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There really is nothing like looking at the sky while lying down in a boat in the South Pacific two hundred miles from the nearest electricity. Next time, I'll try to remember a telescope.

I think you are making it much more convoluted than it is.

From your point of view, what you do in the next few minutes is partly down to what you choose to do and partly down to what circumstances allow.

From the point of view of someone in the year 2108, your actions happened 100 years ago.

Your actions will have had some effect on that future world, although for most people the effect will be extremely slight.

"I've gone all cross-eyed"- Austin Powers

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Carl Matherly

Offical Battlestar Galactica Apologist

Named Time Magazine's 2006 "Person of the Year"

Hmmm... Seems to me that, for the people in the present, the state of things was shaped by the things that was done in the past, so from the point of view of someone in now, the past would be immutable. But from the point of view of a person in the past, the things they experience is experienced for the first time, and they are free to choose their actions as they would, so the future is mutable to them, since it has not happened yet.

This does not mean that the people in the past could suddently choose differently than what they did from the point of view of the time travler, to him or her, the stuff allready happened. It is all perfectly logical and without any paradoxes.

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Game over, you lose, we hope you enjoyed playing the exciting game of Thermodynamics...

Paul, TrAI, I think where there's a breakdown here is the idea that "mutable" is dependent on point-of-view.

I could have chocolate milk or white milk tomorrow morning (the 8th). If a time-traveler from the 9th, with knowledge of what I drank on the 8th, were to come back and interact with me today, could I still have either type of milk tomorrow morning, or am I restricted to what the time-traveler knows I had/will have?

If I'm restricted, then why would I not be restricted if the time-traveler doesn't interact with me? If I am restricted even if there's no interaction, then why wouldn't I be restricted if the time-traveler doesn't even travel back? In fact, why am I not restricted if the time-traveler doesn't even exist? I may not be aware that my milk choice is immutable, but if it is, it is.

If I am still able to do either one, though, then the time-traveler's "past" is not immutable.

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SeanF

"Ask to understand, but don't challenge unless you have the knowledge."--NEOWatcher

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