### Flow equations for Hamiltonians

**Wegner, F ***(Heidelberg)*

Tuesday 26 August 2008, 14:00-15:00

Seminar Room 1, Newton Institute

#### Abstract

This is a method to diagonalize or block-diagonalize a Hamiltonian by a
continuous unitary transformation.
After an introduction into the method a short survey of applications are
given.
As an example the elimination of the electron-phonon interaction in
second order in the coupling is performed.
Then a gradient-procedure which minimizes a cost-function is shown.
A procedure to bring the Hubbard Hamiltonian to molecular-field form is
given as a second example.
Original paper:
FW, Annalen der Physik (Leipzig) 3 (1994) 77