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arXiv · hep-th/9910103

Modal expansions and non-perturbative quantum field theory in Minkowski space

Nathan Salwen·Dean Lee
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Abstract

We introduce a spectral approach to non-perturbative field theory within the periodic field formalism. As an example we calculate the real and imaginary parts of the propagator in 1+1 dimensional phi^4 theory, identifying both one-particle and multi-particle contributions. We discuss the computational limits of existing diagonalization algorithms and suggest new quasi-sparse eigenvector methods to handle very large Fock spaces and higher dimensional field theories.

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Nathan Salwen, Dean Lee. 2000-01-20. Modal expansions and non-perturbative quantum field theory in Minkowski space. https://doi.org/10.1103/physrevd.62.025006

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