Of course you may share them!
I'm perfectly happy for you to use this/my work however. Technically it'd be a "Attribution CC BY" - Copying, changing, distributing are all freely allowed as long I'm credited somewhere. (Andy Jenkinson/Uglifruit).
Looking at the CC website - their wording is "This license lets others distribute, remix, adapt, and build upon your work, even commercially, as long as they credit you for the original creation. This is the most accommodating of licenses offered. Recommended for maximum dissemination and use of licensed materials."
Hope that helps, and if you need anything else / source code / notes then please let me know.
Also, I've posted a quicker (slightly better) version of this here: https://uglifruit.itch.io/physiced-speed-tweak