ABSTRACT
The principle of least action is https://www.w3.org/1998/Math/MathML"> δ ∫ t 1 t 2 d t L ( q , q ˙ ) = 0 , https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781003287803/a112f4d0-c5ab-4fbb-9ab7-9ffda30997aa/content/math1_1.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/>
