Time Travel 3: No Blasts From the Past

Many time travel stories involve traveling into the past and altering it, with the result that the future to which the time traveler returns is also changed -- whether for good or for ill (perhaps depending on which Back to the Future film one is watching).

Ray Bradbury's "A Sound of Thunder" (the short story, not the less than mediocre film) is the paradigmatic case here, wherein a dinosaur hunter (another familiar time travel trope) steps off a marked path and squashes a butterfly. The upshot of that seemingly insignificant change in the past is that the future somehow feels different, as Bradbury so wonderfully describes:

Eckels stood smelling of the air, and there was a thing to the air, a chemical taint so subtle, so slight, that only a faint cry of his subliminal senses warned him it was there. The colors, white, gray, blue, orange, in the wall, in the furniture, in the sky beyond the window, were... were.... And there was a feel. His flesh twitched. His hands twitched. He stood drinking the oddness with the pores of his body. Somewhere, someone must have been screaming one of those whistles that only a dog can hear. His body screamed silence in return. Beyond this room, beyond this wall, beyond this man who was not quite the same man seated at this desk that was not quite the same desk... lay an entire world of streets and people. What sort of world it was now, there was no telling. He could feel them moving there, beyond the walls, almost, like so many chess pieces blown in a dry wind.

Furthermore, the words on the wallsigns are spelled differently, and the wrong guy has just won the election!

As much as I love this story, it just doesn't add up. In increasing degrees of incoherence...

(1) While I buy the idea that a small change can have a dramatic effect (and this is where we get the phrase "the butterfly effect," after all), it's extremely unlikely that the ripple effect would leave the present intact enough for the same two candidates to be running for office but different enough for loser and winner to switch places. Likewise, while a change in language is possible, it's likely the change wouldn't simply be a matter of different spelling.

(2) The idea that the time travel agency could safeguard the timeline by creating a path and marking the target animals doesn't sit well with the idea that any minuscule change might be catastrophic. Surely they can't be tracking insects--and even microsopic organisms--to make sure none are inadvertently extinguished by a time traveler. Given the butterfly effect, it seems inevitable that any travel to the past would have serious repercussions in the present

(3) The past is the past (pace William Faulkner). It's already happened. So if anyone leaves the future in a time machine, their arrival in the past has already transpired and whatever they do has already been done. It isn't as if there is a pre-time-travel past (with a living butterfly) and a post-time-travel past (with a dead butterfly). No, there's just one past. So while time travelers may be able to visit the past, and if so they can certainly affect it, they cannot change it. Wanna know what that kind of time travel looks like? Watch 12 Monkeys.

If I'm right about this, then many time travel stories don't make sense, in spite of how much fun they might be. This post has to end, but I can't help observing that Back to the Future's idea that as the past changes people will fade out of a photo from the future is especially ridiculous.

Chaospet (the source of the last link) has a nice trilogy of webcomics on this issue: 1, 2, 3.

Wondering about the possibility of multiple timelines? Stay tuned.

Where Is My Well Thought Out Twinkle?

Maybe it's just me, but a song with the title "Well Thought Out Twinkles" and that sounds and looks like this feeds the parts of me that hunger for sf and for philosophy. The band is the Silversun Pickups, from their 2006 release Carnavas.



And, of course, when I think of philosophically-minded music, the classic Pixies tune "Where Is My Mind?" always comes to mind. Here it's fittingly played against the backdrop of cuts from Fight Club. Warning: don't watch this if you haven't seen the film (and care about seeing it).



You might also listen to this while reading Daniel Dennett's mind-blowing piece "Where Am I?"

Time Travel 2: Time Wars

A long time ago... or a short time ago... or some time in the future? One of the familiar tropes in time travel stories is the guardian of the timeline. In a world where time travel is possible, the past is seen as yet another venue for terrorists to threaten the world for the sake of their cause and for unscruplous opportunists to try to make a buck without a care for the damage they do. And this new temporal peril calls for a new kind of hero, or a force of heroes, to save the present day--or the future, depending on one's frame of reference. Future warriors fighting their battles in the past! That's pretty cool stuff.

Some classic examples of this kind of story are Poul Anderson's The Time Patrol stories and Simon Hawke's longrunning Timewars series. Also Fritz Leiber's The Big Time, which won the Hugo in 1959.

In film, we mustn't forget Timecop (1994), one of Jean-Claude Van Damme's somewhat less objectionable films, and the three (soon to be four!) Terminator films, which--like the killer robots themselves--"absolutely will not stop, ever." And we mustn't forget The Sarah Connor Chronicles.

What can you add to my list?

Killing machines chasing people through our every day landscape. Time soldiers taking the place of Robin Hood or the Three Musketeers, fighting battles with sword or musket rather than with blasters. Stories in this sub-sub-genre tend to explore the exciting prospects afforded by time travel rather than exploring its logical or physical paradoxes. And one doesn't have to think about such stories for very long to be struck by the utter implausibility of the thesis that a military operation could somehow protect the integrity of the timeline. Still, these stories do raise one of the most philosophically interesting questions about time travel: whether it's coherent to talk about changing the past. But that'll have to wait until the next post.

Time Travel 1

Time travel is one of science fiction's earliest and most enduring themes. Mark Twain gives us what is perhaps the earliest example of a person who is displaced in time in A Connecticut Yankee in King Arthur's Court (1889), while H.G. Wells invents the fiction of a time machine in the aptly titled The Time Machine (1895).

Is time travel possible? In what sense? We may want to know whether time travel is physically possible, given what we now know about the nature of the universe. People have lots of interesting things to say about this. Not me, though.

Philosophers are more likely to wonder whether time travel is logically possible. And this question is intimately connected to the fascinating question of whether an sf story about time travel can be coherent. I'll be assembling several posts on these matters in the near future.

For now, see what some sf writers have to say about the use of time travel in sf at the excellent blog SF Signal.

Big Brother and Little Brother

Cory Doctorow's wonderful Little Brother has been nominated for a Hugo Award and you can check it out for free here. If you read the novel, you'll have a pretty good idea why all of his stuff is available online for free.

The title is (obviously) a reference to the omnipresent looming presence of Big Brother in George Orwell's 1984, which you can also read free online. You might also be interested in the philosopher Peter van Inwagen's paper "Was George Orwell a Metaphysical Realist"?

Doctorow's book takes place in the (all too?) near future of the U.S. and maps out a route into an Orwellian future. Yet it's ultimately a very hopeful book. Significantly, while technology can be the means of the state's oppression and control, in Doctorow's story it's the savviness and technological sophistication of a group of geeks that creates the possibility of liberation.

And it's a really great read.

Batman or Superman?

Who has the better story? Who's the most heroic? Who would win in a fight? What do you think? While you're ruminating, check out the following answer to our questions, in two parts:

Watch The Dark Knight Meets Superman and more funny videos on CollegeHumor

Watch The Dark Knight Meets Superman Part 2 and more funny videos on CollegeHumor

How to Survive an Alien Attack

Or I suppose one could adapt many of the strategies suggested in this, too.

Just for fun!

This is making the rounds. But you don't want to miss it.



Hat tip: SF Signal

And now I just have to add this one....