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arXiv · hep-th/9811158

On the Renormalization of Hamiltonians

G. Alexanian·E. F. Moreno
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Abstract

We introduce a novel method for the renormalization of the Hamiltonian operator in Quantum Field Theory in the spirit of the Wilson renormalization group. By a series of unitary transformations that successively decouples the high-frequency degrees of freedom and partially diagonalizes the high-energy part, we obtain the effective Hamiltonian for the low energy degrees of freedom. We successfully apply this technique to compute the 2-loop renormalized Hamiltonian in scalar $λϕ^4$ theory.

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G. Alexanian, E. F. Moreno. 1998-11-17. On the Renormalization of Hamiltonians. https://doi.org/10.1016/s0370-2693(99)00136-7

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