The 3 Schools of Time Travel Theories, Part 1: Dynamic Timeline

Estimated reading time: 2 minutes

Last Saturday we started this series about time travel theories and the paradoxes that arise from each, with an introduction and a “quick” look at what paradoxes are, why and how they exist. Today we’re going to look at the first, most common, and most paradox-prone time travel theory: the Dynamic Timeline.

You already know this theory if you've watched Back to the Future (and if you haven't, you really should watch it!)

You already know this theory if you’ve watched Back to the Future


This is how the Dynamic Timeline works: You get into your time machine, go back to 1890, kill Hitler in his crib, go back to your present, and BAM! no more Hitler! Every reference to Hitler in books, movies, whatever, has been erased. You ask anyone if they know who Hitler was and they’ll blankly stare at you before moving on with their day. You made it! You saved all those people. The world hasn’t even had a World War II.

Of course, books and movies using the Dynamic Timeline theory warn us that messing with history may have unexpected results. Maybe in the absence of Hitler, someone even worse started World War II, with even more devastating results. Maybe because we never invested time and money into the atom bomb, we missed out on most of the technology we have today.

This is the most commonly used theory for obvious reasons. The idea of being able to change the past to affect the future is something we all wish we had. Additionally, it’s a theory that allows writers to examine both alternate history concepts (“what if…?”) and it has a lot of potential for conflict and drama (the Butterfly Effect is a great plot engine).


Here’s the thing: as much as this theory is easy to work with and understand, it’s also the one with the most problems.

But the biggest of those problems is the Grandfather Paradox. Imagine you’re a time traveler. You get into your time machine, but instead of killing Hitler you decide to find your grandfather and kill him when he’s just a child. This creates an infinitely recurring loop in which your grandfather never grows up and your dad is never born. As a result, you are never born, so you would never have built and gotten into a time machine. But if you’d never have gotten into the time machine, your grandfather would still be alive, have your dad, who’d have you. And you’d get into a time machine and kill your grandfather…


This infinite loop is the biggest issue with the dynamic timeline theory. Anything you do in the past could affect your ability to go back into the past, so how could you have gone back to mess around with the past?

The two other theories exist to solve this one paradox, and we’ll look at those in future posts, starting with the Fixed Timeline theory. In this theory, a more deterministic view of time is taken to avoid the Grandfather Paradox… only for another kind of paradox to emerge.

The 3 Schools of Time Travel Theories – Table of Contents

Part 0: Paradoxes
Part 1: Dynamic Timeline << YOU ARE HERE
Part 2: Fixed Timeline
Part 3: Multiverse

Amante Reale

I'm a freelance writer specializing in tech, gadgets, security, cryptography and cryptocurrency. Warning: I am armed with very strong opinions and I'm not afraid to use them. Hire me!