- #1
juliette sekx
- 31
- 0
Discrete hellmann-feynman theorem ??
The Helmann-Feynman theorem states that :
derivative of eigenvalue with respect to a parameter = eigenfunction dagger * derivative of operator with respect to parameter * eigenfunction
(assuming that the eigenfuncitons are normalized, otherwise the theorem would also include a normalization integration).
Does anyone know if this works for the DISCRETE CASE ??
ie:
derivative of eigenvalue with respect to parameter = eigenVECTOR dagger * derivative of MATRIX with respect to parameter * eigenVECTOR ??
I can't find a proof of it anywhere!
The Helmann-Feynman theorem states that :
derivative of eigenvalue with respect to a parameter = eigenfunction dagger * derivative of operator with respect to parameter * eigenfunction
(assuming that the eigenfuncitons are normalized, otherwise the theorem would also include a normalization integration).
Does anyone know if this works for the DISCRETE CASE ??
ie:
derivative of eigenvalue with respect to parameter = eigenVECTOR dagger * derivative of MATRIX with respect to parameter * eigenVECTOR ??
I can't find a proof of it anywhere!