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Renormalization of Hamiltonians

Stanislaw D. Glazek
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Abstract

A matrix model of an asymptotically free theory with a bound state is solved using a perturbative similarity renormalization group for hamiltonians. An effective hamiltonian with a small width, calculated including the first three terms in the perturbative expansion, is projected on a small set of effective basis states. The resulting small hamiltonian matrix is diagonalized and the exact bound state energy is obtained with accuracy of order 10%. Then, a brief description and an elementary illustration are given for a related light-front Fock space operator method which aims at carrying out analogous steps for hamiltonians of QCD and other theories.

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Stanislaw D. Glazek. 1997-06-21. Renormalization of Hamiltonians. https://arxiv.org/abs/hep-th/9706149

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