Numerical Test of Molecular-Field Renormalization Group

A NUMERICAL RENORMALIZATION GROUP APPROACH FOR AN ELECTRON-PHONON INTERACTION

A finite chain calculation in terms of Hubbard X-operators is explored by setting up a vibronic Harniltonian. The model conveniently transformed into a form so that in the case of strong coupling a numerical renormalization group approach is applicable. To test the technique, a one particle Green function is calculated for the model Harniltonian

1 Wilson’s Numerical Renormalization Group

The idea of the numerical renormalization group (NRG) for a quantum-mechanical system with Hamiltonian H is to obtain the many-body eigen-states and eigenvalues on all energy scales ω 1 > ω 2 >. .. in a sequence of steps, with each step corresponding to a distinct energy or length scale [1]. This is achieved by a formal procedure of tracing out high energy states to (RG) transformation R relate...

a numerical renormalization group approach for an electron-phonon interaction

a finite chain calculation in terms of hubbard x-operators is explored by setting up a vibronic harniltonian. the model conveniently transformed into a form so that in the case of strong coupling a numerical renormalization group approach is applicable. to test the technique, a one particle green function is calculated for the model harniltonian

A Renormalization Group for Hamiltonians: Numerical Results

We describe a renormalization group transformation that is related to the breakup of golden invariant tori in Hamiltonian systems with two degrees of freedom. This transformation applies to a large class of Hamiltonians, is conceptually simple, and allows for accurate numerical computations. In a numerical implementation, we find a nontrivial fixed point and determine the corresponding critical...

12 The Numerical Renormalization Group Ralf