Joseph-Louis Lagrange
Person
Provided a general proof for the principle of least action using Euler's methods and developed the Lagrangian formulation.
Mentioned in 2 videos
Videos Mentioning Joseph-Louis Lagrange

Cumrun Vafa: String Theory | Lex Fridman Podcast #204
Lex Fridman
Reformulated Newtonian mechanics with Euler using the principle of least action, which proved foundational for quantum mechanics.

The Closest We’ve Come to a Theory of Everything
Veritasium
Provided a general proof for the principle of least action using Euler's methods and developed the Lagrangian formulation.