1. Homura Explains Time Travel
Anime Midwest 2017

2. Spoilers
For any media that involves time travel, chaos theory, or multiple selves

3. Spoilers for all of these

4. Topics What is Time Travel? Is Time Travel possible?
Multiple universes
Can history change?
Looped time

5. What is Time Travel? Travelling forward fast Travelling forward slow
Travelling backward

6. What is time?
(Matrix Reloaded)

7. What is entropy?
Disorder
“Time's Arrow”
Asymmetric
Kyubey hates it

8. Relativistic causality
Light cones
Y-axis is time
X-axis is space

9. Lorentz Transform Green is normal space-time A and B are simultaneous
Red is skewed
A is before B
Blue is skewed
B is before A
(Wikipedia)

10. Lorentz Transform
Space contraction
Causality preserved
(Wikipedia)

11. Is such a thing even possible?
Time dilation is proven, GPS
Backwards travel is impossible (for now)
Human record for forwards travel is 23 milliseconds, Sergei Krikalev, MIR
(Not Sergei)

12. Fictional Time Travel Malleable history (BTTF)
Fixed history (Harry Potter)
Multiple Universes (Madoka)

13. Ontological paradox “Bootstrap Paradox” Item is passed back in time
Item has no origin
(xkcd)

14. Grandfather paradox Bootstrap paradox but sexier
Still impossible in known causality
Futurama did it

15. Time Ripples
Resolves paradoxes
Kind of not really
(Achron RTS)

16. There's got be a better way!
Typical time traveller dealing with paradoxes

17. Multiple Universes
(Matrix Reloaded)

18. Multiple Universes

19. Divergence / Chaos
“Chaos … Highly sensitive to initial conditions” (Wikipedia)
Similar past is not similar future
(Stein's;Gate)

20. Sources https://www.reddit.com/r/vxjunkies
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