Show that energy is decreasing - PDE - Energy
93848
Proving energy conservation for wave equation
142596
Evans PDE Chapter 5 Problem 11: Does $Du=0$ a.e. implie $u=c$ a.e.?
85094
A problem from Evans' PDEs book: find a Lagrangian for a given Euler-Lagrange equation
29096
Non-uniqueness of solutions of the heat equation
62971
About smooth approximation in a Sobolev space
18144
Does a nonzero Poynting vector mean that there is propagation of energy?
153727
Constant term in Lagrangian
893
Simple PDE with Neumann BC
43001
Proof for Dirichlet Function and discontinuous
28888
The functional $I[w] = \int_U \frac{1}{2} |Dw|^2 - fw \, dx$ is weakly lower semicontinuous
119004
Proof of conservation of energy?
79822
Problems with partial derivatives.
2129
Showing that the derivative operator is not bounded on $L^2 (\mathbb{R})$
41666
How to solve a system of PDEs with zip condition?
47168
PDE separation of variables
90716
Conservation of energy and wavefunctions
114562
Boundary conditions for calculus of variations in phase space and under canonical transformations