View Single Post
Mar17-04, 05:22 PM
P: 1
I'm reading the first edition of Mechanics by Landau et al, published in 1960. Just before equation 3.1 on page 5 it says exactly this:

"Since space is isotropic, the Lagrangian must also be independent of the direction of v, and is therefore a function only of it's magnitude, i.e. of v(bold)^2 = v(italic)^2:

L = L(v(italic)^2) (3.1)"

This seems very cryptic to me since the magnitude is sqrt(v(bold)^2) =
Could someone fill in the missing details for me please?

Phys.Org News Partner Physics news on
Engineers develop new sensor to detect tiny individual nanoparticles
Tiny particles have big potential in debate over nuclear proliferation
Ray tracing and beyond