Twin paradox, by Dr Don Lincoln of Fermilab (very unsatisfying, very unusual for Dr Lincoln, but maybe it will work for you).
Twin paradox: the real explanation
Twin paradox: the real explanation (no math)
Sabine Hossenfelder
This is the best explanation I encountered, but viewing it the first time, I still did not understand to my satisfaction. Now it makes perfect sense.
Special Relativity: This Is Why You Misunderstand It
Dr Lincoln feels the need to respond
Does acceleration solve the twin paradox?
The YouTube series that helped me finally understand it.
Relativity by eigenchris
Space travel calculator. I used this to build my acceleration chart
https://www.calctool.org/relativity/space-travel
Wikipedia entry on twins paradox:
https://en.wikipedia.org/wiki/Twin_paradox
Flying atomic clocks around the world:
https://en.wikipedia.org/wiki/Hafele–Keating_experiment
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