Uploaded July 2019 | Updated September 2026, 3 weeks ago

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Is Lagrangian mechanics powerful enough to replace Newton's laws? What does the principle of least action say about cause and effect (causality)? What the heck is an action? Let's find out!
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VIDEO ANNOTATIONS/CARDS

Lagrange Points:
youtu.be/TryOFDe2K7M

What the HECK is Energy?
youtu.be/snj1wBtn6I8

Is Math the Language of the Universe?
youtu.be/inPcQeYWVT8
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RELATED YOUTUBE VIDEOS

Up & Atom on Lagrangian Mechanics:
youtu.be/dPxhTiiq-1A

Eugene on on Lagrangian Mechanics:
youtu.be/EceVJJGAFFI

3blue1brown on Phase Space:
youtu.be/p_di4Zn4wz4
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OTHER SOURCES

http://www.feynmanlectures.caltech.edu/II_19.html
physics.stackexchange.com/questions/15899/why-the-principle-of-least-action
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LINKS TO COMMENTS

youtube.com/watch?v=iyN27R7UDnI&lc=Ugw-IgHHMslVfGQDqJt4AaABAg
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IMAGE CREDITS

Lagrange:
commons.wikimedia.org/wiki/File:Joseph-Louis_Lagrange.jpeg
commons.wikimedia.org/wiki/File:M%C3%A9canique_analytique.jpg

Fermat:
commons.wikimedia.org/wiki/File:Pierre_de_Fermat.jpg

ibn al-Haytham:
commons.wikimedia.org/wiki/File:Hevelius_Selenographia_frontispiece.png