Is there Calculus of Variations in Mathlib?

Stream: mathlib4

[Mr Proof]

For example if I want to prove that

$$\frac{\delta}{\delta A_\mu(x)} \int_{\mathbb{R}^4} |F|^2 dx^4 =-2 \partial_\mu F^{\mu\nu}(x)$$

where F is the electromagnetic tensor.

[Kenny Lau]

you might want to ask in #PhysLean