Welcome, dear readers, to the afterword for 'Moebius 2157', in which I would like to explain some of the ideas and inspiration for this story.

As you probably know by now if you've read this far, one of the main themes of this story is the 'grandfather paradox', which was part of the ONC prompt I picked, Speculative Fiction #5: An individual is somehow transported back in time and because some tropes are too wonderful to avoid, they inadvertently kill their grandfather. In a direct contradiction of everything everyone has ever been told, however, they do not cease to exist...

I guess you can now also see why I avoided mentioning it in a preface or even in the blurb. Judging from some reactions following Alyssa's first time jump, I feel like the surprise worked fairly well! And I do hope that in general, the twists and turns I came up with managed to surprise you.

"Now, talking about twists and surprises. I think there are some open questions about what happened in the last chapter. I admit, it was all a bit ambiguous... so I decided to bring our favorite three egghe- I mean, scientists together to explain some of it."

A lanky figure sitting at the table clears their throat.

"Oh! Of course, there is also Travis the Computer Guy here today. Hi Travis, so good to see you again. The readers really liked you, so I think they'll be happy to see you're back."

"Thank you," Travis nods appreciatively.

"So, as I said, our three scientists here-"

"I thought you're a scientist too," Rosie interrupts.

"Well, I'm a molecular biologist, not a physicist."

"But you wrote this thing," Baker says. "Surely you have to be able to explain it yourself?"

The author shrugs. "The people who've read the story liked you guys, whereas I am just the mean, evil author. I figured it would be better to leave the talking to you. How about you start, Rosie? Maybe you could tell the readers something about the title of this story?"

Rosie's face lights up with a smile. She nods and eagerly reaches for her stack of papers.

"Ah, yes. So let's start by explaining what 'Moebius' means."

She begins by making neat, sharp folds along the edge of a sheet and then tearing it into thin strips. She picks one up and holds it up at the ends.

"A strip like this has two sides (or surfaces) and one edge (or boundary). Now if we put the ends together... we get a simple loop. It has two surfaces – inside and outside – and now two edges."

She fixes the ends with a piece of tape, and puts the loop aside. Then she takes another strip of paper, and twists one of its end by 180° before putting them back together and fixing them. The new paper loop now distorts awkwardly as she places it on the table.

"Now this is a so-called Moebius strip, or Moebius band. It is defined as a structure that has only one surface and one boundary (edge). Now think once again about our 2D paperworld example, a circle living on this side of the loop..."

She points to the outside of the normal paper loop.

"...has no way to reach the inside of the loop, and vice versa (assuming it cannot cross the boundary/edge). On the Moebius strip however..."

She takes a pen, and begins to trace it along the Moebius band, drawing a red line. She rolls the loop along the table and keeps drawing, until eventually, she arrives back at the beginning of the trace of her pen, in one single line.

"It's a loop with only one surface. So what looks like the outside here is the inside over there, and vice-versa. There is actually no inside or outside on this loop."

"So what does this have to do with the story?" Travis asks.

"The idea was that in this story, we end up with two time loops that exist in parallel. In one, we have a grumpy version of Alyssa. In the other, we have our protagonist. And in our story, they come together. The two timelines intersect, so to say-"

"A Moebius strip doesn't intersect with itself, though," Baker chimes in, sounding smug. "It just looks like that in that picture the author drew for the last chapter."

"True," Rosie admits, "But think about it like this."

She takes a new paper strip, and quickly hatches it with red pen. Then she flips it over and does the same on the other side in blue, before she forms a regular loop again, red side out, blue side in.

"A circle living on the blue side cannot reach the red side. But as a 3D being, I can draw on whichever side I want. So what would have to happen for the circle to be able to go to the other side? Well..."

She rips the loop apart and forms another Moebius band from it. Now where the ends touch, blue and red come together.

"That's what happened in our story. This is what happened at the second time jump. A transition from one loop to the other."

"Ah," Baker exclaims. "A transition through a higher spatial dimension..."

Travis tilts his head, and a furrow appears on his brow. "The two time loops turned into a Moebius loop?"

"That was the idea behind it. The time jump that Alyssa made caused the two time loops to... well, intersect is really not the appropriate word, I guess. But this is how she met another version of herself in 2107," she points to the blue-red Moebius band, "instead of her past self," she traces her finger across the outside of the regular paper loop, " and instead of simply entering a new timeline," she points to another, fresh strip of paper on the table.

"That still sounds awfully convoluted," Travis comments.

"Hm, well, how about some input from our best science communicator," the author suggests. "Leon?"

Across the table, Leon meets her expectant look with a sulking expression. He crosses his arms and presses his lips together in a thin line.

"Aww, come on," the author says, "you can't still be mad at me...?"

He glowers at her.

"Okay. Okay, I get it!" The author raises her hands defensively. "I'm sorry for what I did, okay? Now how about we tell the audience a bit more about the inspiration to this story and then we get to the funny bloopers and after-credits scenes?"

Leon remains silent. If looks could kill...

"There's a happy end in at least one of them," the author teases.

He doesn't respond.

"And I mean a very happy end." She grins widely.

Leon huffs and turns his face away.

"Dude, stop sulking already!" the author exclaims, "We get it, I'm evil, I treated you really, really badly and I'm sorry, okay? But look, I even brought Travis back, so I promise you'll be with Ally in a few paragraphs, okay? Just let me finish this-"

"And how is any of that supposed to get me through the trauma of her potentially being my own damn granddaughter?!" Leon suddenly snaps at the author.

At his words everybody at the table freezes for a moment. Then they all turn to stare at the author expectantly.

"Oh. Well. About that...." she mumbles.

Rosie clears her throat. "For the readers who are less familiar with time travel stories, maybe we should explain that this is a kind of time-travel trope. So in this case, because Alyssa's mother hadn't been born by the time she kills Pandora, it's likely that Alyssa, after having taken Pandora's place, eventually gave birth to her own mother."

"Actually, I think there's a plot hole," Travis remarks. "I mean, I get it that our protagonist could become her own grandmother, and eventually gave birth to... a child of, uhm... ambiguous paternity..."

He casts and uneasy glance at Leon, who clenches his jaw tightly.

"But in the first time loop," Travis continues, "the one with the mean version of Alyssa - she broke the device during the first jump, because she didn't give her key away. But if she can't jump back and hook up with Leon, he can't be the father of the child that becomes her mother in that time loop. So did she hook up with... Espira?"

The author wears a devious smile as she shrugs and nods her head at Leon. "Who knows? Remember that there was a fade to black in the scene with the cookies before the first jump? We don't actually know what happened in that room."

They all whirl around and now face Leon with their curious stares. He blushes to the roots of his dark hair.

"Uhh... I... uhm..."

The author giggles, and it sounds awfully like the maniacal cackling of an evil witch.

"You said you didn't skip anything important!" Baker huffs.

"Well. Not in the timeline that our narration follows. But maybe grumpy Alyssa showed a bit more initiative in her own timeline? Like I said. Who knows..."

Dissatisfied with her evasive answer, Travis grumbles something under his breath, but the author ignores him.

"Let's continue. What other questions are there?"

"So are we in a multiverse or not?" Leon addresses the author now. "Or do only these two timelines exist, red and blue?"

The author clears her throat. "Well, as I said, I'm not a physicist... but simply put, I wrote this story because I wanted to reconcile these two ideas that come up in time travel stories a lot: The idea of a multiverse, where each decision causes a new timeline to branch of, and a time loop, where any decision made only leads back to the same, inevitable future.

"We never learn if our protagonist actually creates a new timeline with a better future, as Leon suggests. There is no way to check. And the existence of a looped timeline would argue against a multiverse. The war and the exodus to the bunker city seem inevitable. But on the other hand, we clearly have more than one timeline in the story. That of grumpy Alyssa and that of 'our' Alyssa.

"The way I thought about it is like this: There is a multiverse, yes. Occasionally, one of the timelines that branch off at any random point gets caught up in a loop. In this case, the loop is created as Alyssa jumps back in time, only to end up creating the circumstances that allow her to jump in the first place through funding Last Hope. But there had to be an 'original' timeline at some point, in which somebody else funded the project. Maybe it was that philanthropist Mister Devon, who got shot in Room 57 (sorry about that, by the way!).

"In that original timeline, (grumpy) Alyssa jumped back, but got stuck in 2107. She assumed the role of Pandora, but did not manage to improve the future as she had hoped. So she contributes to Project Last Hope, enabling her future self to jump, perhaps hoping that the next time, she would do better. And from that point on, we get the first loop.

"After an indefinite number of iterations, the looping timeline (loop 1) gives rise to our protagonist. She is just a little bit different... a bit softer, more compassionate. That's why she gives away her key, and can go back to 2157 because her device doesn't break. This sets in motion the events that create the second loop. A more compassionate, more 'experienced' version of Alyssa, who eventually takes up the name Nadja, funds Project Last Hope."

"So we are in a multiverse in which sometimes, out of the infinite possibilities of things that can happen, time loops arise," Leon summarizes. "We just had the... questionable luck of being part of the one that makes the plot for this story."

"That's one way to put it."

"That means we're just caught in a loop again and there is no way to save the world," Travis notes sullenly.

"Well, not really. We don't know what exactly happens after the credits roll," the author argues. "I like to think that Old Lady Alyssa has an awesome plan to save the world. Just because there's a loop doesn't mean there has to be a bad ending."

"Now that's rather grand coming from the person who put that Nietzsche quote at the end," Rosie remarks drily.

"Sorry," the author cracks a lopsided smile. "But it actually fits very well. The quote references the myth of Pandora's box (yes, Alyssa's grandmother is not named like that by coincidence. Also, the name 'Nadja' means 'hope' in Russian, and Alyssa's surname is based on the biblical figure Cain).

"In some versions of the myth, after all the evil in the world has escaped Pandora's box (or jar) she opens it a second time, and releases hope. Relating to this, in our story, protagonist-Alyssa jumps a second time, and it takes this version of Alyssa, the compassionate one with the little extra experience to really save the world in the long run.

"Some people, like Nietzsche, believe that hope is actually part of the punishment, part of the evils that came out of that jar. Similarly, the ending is left a bit ambiguous. We can hope that Old Lady Alyssa saves the world, but we don't know for sure. Make of it what you will – I thought it fits very well."

"So, about that subjective timeline..." Travis says, "You keep mentioning that, but what does that even mean?"

"Simply put: the question of whether there is one or many timelines, or a time loop, actually doesn't really matter in the end. It's only a 'loop' from a hypothetical, outside observer's perspective (like the readers'). But the protagonists of the story won't really notice either way. Think about it like this: In loop 1, Alyssa jumps back but the dystopian future still comes to pass, causing (another) Alyssa to jump back. But each individual version of Alyssa only perceives a single, linear timeline, from her birth up to 2157, then after the jump from 2107 to her death."

"This is getting very philosophical now," Baker remarks.

"I included that as a nod to the concept of a Theory of Mind," the author elaborates, "But I think this would stray too far from the topic now. My other story, The 10th Circle, delves into a couple of similar, philosophical ideas. But as for Moebius 2157, the concept of a 'subjective timeline' has another implication."

She turns to face Leon. "You realize what that means, right? We follow Alyssa for the most part of the story, but the Old Lady we meet in the end is not the same Alyssa."

"Oh!" Rosie exclaims. "I get it. Because if our Alyssa was number 'n', then the Old Lady would be 'n-1', the previous iteration of the loop..."

The author nods.

"That was how I wanted to approach the prompt for the Open Novella Contest, the so-called grandfather paradox. In a multiverse, it probably doesn't matter if you killed your own grandparent before the conception or birth of your parent. Because you create a new timeline in which the grandparent is now dead, and that has no effect on your own past, which happened in another 'branch' of the timeline. But what would happen in a non-multiverse? Shouldn't you go 'pfft' and disappear?

"Personally, I think that even in a non-multiverse, there would be no effect whatsoever. You would still just experience a linear timeline that is unaffected by whatever you chose to do. So whenever somebody jumps into the past, they don't access their 'own' past but rather a copy of their past, an alternate version. This small strip of 'past' becomes part of your 'present'. Your own past has already happened, in your subjective timeline. The alternate version of the past ceases to exist the moment you return to your own future, because you are no longer there to experience it. The only way for that alternate version of the past to continue to exist and progress is for you to stay there..."

"...and wait it out," Leon mumbles. "Like what Ally chose to do, rather than believing she had made a better world that she could never see or even know for sure existed."

"Interesting, interesting," Baker hums.

"Wow," Rosie says. "My head is spinning."

"Goddammit!" Travis suddenly cries out. "To hell with all that subjective bullshit. All I wanna know: IS Leon her grandfather now or is it Espira?!"

They all stare at the author again as she laces her fingers together and props her head up on her hands as she looks at her characters across the table. She cracks a grin.

"I guess we'll never know."

The characters groan collectively.

"Anyways. I think this concludes our brief Q&A... for now. I hope this covered the most important questions, but if anything is still unclear, feel free to chime in here or in the previous chapter, and I'll make sure to answer through lunatic comments or shoehorn my response into some semi-funny dialogue over here," the author says and gestures around herself.

"Thanks for bearing with my lengthy descriptions, excessive scientific explanations, unnecessary cruelty to children and completely unjustified fourth-wall-breaking. I appreciate your support! And now, without further delay, here are a couple of scenes that... well, let's just say, they didn't quite make the cut. Enjoy, and keep your Moebius tissues ready – you might cry from laughter."