What the Fran

Time travel brain breaking

I've played around with a few different time travel stories, fics, chapters, now. Actual time travel or more on the timeline-altering alternate universe side. And every time I say to myself, No. No more. This is too hard. You have to stop.

And I don't stop.

In fact, I'm doing it again.

So I need to ramble about time travel for a while.

There are so many many different types of time travel. I'm specifically interested right now in a deliberate moving around in time vibe. So in brief, to my mind, these are the main ones I think of, with other stuff being flavours or variants:

Fixed is where everything already happened. It's all inevitable. A closed loop. If you try to change something bad you'll probably find you caused the bad thing. You can't shoot your grandfather because you didn't shoot your grandfather because you wouldn't exist to do it if you had.

Branching is multiple universes. Changes create new timelines. Infinite timelines and realities. If you shoot your grandfather you're in a new, grandfather-less world. Choices have impacts, there are sacrifices.

Updating / changeable / dynamic time travel means if you go into the past and mess about you could come back to a very different present. If you shoot your grandfather you could pop out of existence. Who knows! There are consequences to actions and responsibility to grapple with. There's also the most potential for plot holes and paradoxes, thus headaches for the writer.

Time loops are dynamic but then voided at the repeat. And a lot of fun. Who remembers what? Often the time traveller is the only one, but maybe even they don't. Tension! Or as with On the Calculation of Volume by Solvej Balle, what can they change, who remembers - and why?

In Michael Crichton's Timeline they don't time travel at all - they use space travel, because time isn't real, it's just a quirk of human perception. They are travelling elsewhere in the multiverse: 'quantum technology to manipulate an orthogonal multiverse coordinate change.'

Jumping forward time travel when people are only being moved forward in time via space travel, magic, a mishap, or some cryosleep type device isn't what I'm particularly interested in at the moment. Though I do love someone from the past trying to get to grips with our world stories.

A big question - the big question - is, Can the past be changed? When timelines can be changed that's a whole new layer of scrutiny and responsibility for the characters. They could contaminate the timeline. Writing it is fun because you get to think through all these ripples. Like an AU, if you tweak this one thing what changes.

Also, while the author and then the reader know what kind of time travel is going on, do the characters? The characters thinking this is changeable when in fact it's fixed is juicy tension.

Sometimes stuff not changing is explained away by Time or The Universe having some natural balancing mechanism. Maybe it's hard to change the past because things butterfly effect back to homeostasis. Circumstances are multilayered. It's not just one change. Maybe it's hard to change things because constraints scale. Like killing a person requires a lot more energy, sacrifice, whatever, than just walking around. Maybe Time has antibodies, resists damage, and can heal. Maybe some events are too heavy, they remain fixed.

Often there are rules. Enforced by a bureaucracy or just Time. You can't meet yourself, is a common one. Because it's the law, or reality will implode, or whatever. I actually really enjoy characters meeting themselves but I understand it can complicate things too much.

In addition to the grandfather paradox there are many other forms of temporal paradox (but also Novikov's self-consistency principle.)

Such paradoxes include the causal loop or bootstrap paradox where something exists just because it does. I don't see this as a paradox, more as something fun. In The Psychology of Time Travel by Kate Mescarenhas these items are referred to as genies. In Audrey Niffenegger's Time Traveler's Wife their entire relationship is its own loop. The notebook of dates is another one.

People like to say that internal consistency is key. As long as you stick to your own rules. But, you know, we're disproving science and Facts and the status quo all the time and finding new ways to do things. If I really want to break the rules there will be a way to break the rules. However, those are then the new rules. It can't be a one-off. Plus authors love to subvert any expectations.

There are many perils of time travel, including philosophically. One that particularly bothers me is how with branches and the multiverse there are infinite other worlds to consider. The characters create these other timelines, full of problems and suffering. Increasing the suffering of the multiverse by orders of magnitude. Changing things only prevents suffering for one particular timeline and if they've created multiple new timelines to do so the overall damage has still gone up, surely?

Another problem: if it's possible to prevent an atrocity, why haven't they all been prevented? If people had gone back to 1933 or whenever and fixed things we'd be living in a very different world. Well, one might say, something else would have happened. Okay, so fix that too. The whole gig would just be historical whack-a-Hitler.

Often the advice is choose a type of time travel first and build around that choice. Whereas I like to think about which fits the themes and the plot. I've done branching and the branching was the entire point. I've done fics where it's fixed. This story I'm noodling with currently is an updating/dynamic timeline because I want that threat of things changing, and the plot shenanigans of things changing.

Themes-wise, lot of time travel is about grief, loss, and regret. The Time Machine, arguably the first modern time travel story, isn't. It's for funsies. He just gets on that thing and goes. And learns his lesson. Notably in the (relatively) more recent film adaptation this motivation is completely changed.

There's a weight to knowing the future. It creates a burden of shielding people from it, constantly self-censoring. There's an existential anxiety to time travel. Fate, inevitability, agency, responsibility, belonging... time travel has it all. There's also huge comedic potential if one wants to go the way of the fish out of water. Or commenting on society. Time travel has it all and of course can be applied to any genre.

Logistically, writing it is a full nightmare for me. I've got a branching time travel story I wrote for Nano many years ago. It seemed manageable, dealing with two timelines. Then I had to add a third, the timeline some people had left. Then a fourth, what happened in a previous branch to cause people to create the first branch. Then a fifth on the other side. Aaand it only got more complicated from there, ending up with a spaghetti mess. A central plot point of this current idea is fully turning my brain inside out on whether it's a paradox or not, what would actually happen, what I want to happen, and so on.

Maps proved very useful. Of timelines and of character's timelines when these are not linear. These can get a bit abstract and spiralling and contain many more layers than I originally thought.

The timeline and the narrative are two different things. So there's cause and effect being played around with in the chronology but the narrative itself also needs cause and effect. In non-time travel stories these are the same cause and effect. But not in time travel!

Nothing is that simple with time travel.

More notes about time travel. Obviously there's so much more to time travel but this is what is especially bothering me right now.

Some links specifically about writing it:

Fittingly for a post about time travel this was written sometime in the past and has travelled through time to pop out here, while I am at a wedding.

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