Useful Time Travel Is Impossible. But Fun to Think About.
The folks at Kurzgesagt have done a few time travel videos now, but this one is notable for its concise, intuitive explanation and visualization of our constant speed through spacetime (special relativity).
Everything in our universe moves at the speed of light through four dimensional spacetime. Your speed through spacetime is the sum of your separate speeds through time and space. It is impossible for you to stay still. Even if you are not moving through space dimensions, you are moving through the time dimension, blasting face first into the future.
You can slow down in the time dimension, by moving faster through the space dimensions but in total, you will always move at the speed of light through spacetime.
And you can “trade” moving through space for moving through time: “Move faster through space, go slower in time. Move slower through space, go faster in time.” Or as a commenter put it:
Your speed is constant. So the faster you move through the space dimensions, the slower you move through the time dimension, and vice versa.
Not sure this textual explanation makes as much sense as the visualization in the video, so maybe just watch that? Oh, and check out the sources for the video.
Discussion 0 comments
Hello! In order to leave a comment, you need to be a current kottke.org member. If you'd like to sign up for a membership to support the site and join the conversation, you can explore your options here.
Existing members can sign in here. If you're a former member, you can renew your membership.
Note: If you are a member and tried to log in, it didn't work, and now you're stuck in a neverending login loop of death, try disabling any ad blockers or extensions that you have installed on your browser...sometimes they can interfere with the Memberful links. Still having trouble? Email me!
In order to leave a comment, you need to be a current kottke.org member. Check out your options for renewal.
This is the name that'll be displayed next to comments you make on kottke.org; your email will not be displayed publicly. I'd encourage you to use your real name (or at least your first name and last initial) but you can also pick something that you go by when you participate in communities online. Choose something durable and reasonably unique (not "Me" or "anon"). Please don't change this often. No impersonation..
Note: I'm letting folks change their display names because the membership service that kottke.org uses collects full names and I thought some people might not want their names displayed publicly here. If it gets abused, I might disable this feature.
If you feel like this comment goes against the grain of the community guidelines or is otherwise inappropriate, please let me know and I will take a look at it.
Hello! In order to leave a comment, you need to be a current kottke.org member. If you'd like to sign up for a membership to support the site and join the conversation, you can explore your options here.
Existing members can sign in here. If you're a former member, you can renew your membership.
Note: If you are a member and tried to log in, it didn't work, and now you're stuck in a neverending login loop of death, try disabling any ad blockers or extensions that you have installed on your browser...sometimes they can interfere with the Memberful links. Still having trouble? Email me!