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arXiv · 1110.5792

Causality in the relativistic bound-state problem

Vladimir Pascalutsa
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Abstract

Although the exact Bethe-Salpeter equation is certainly the appropriate field-theoretic framework to describe the non-perturbative problem of scattering and bound states, the inevitable truncations introduce inconsistencies such as loss of symmetries or incorrect one-body limit. I conjecture that these problem can be overcome if the truncation preserves the field-redefinition invariance of the exact equation. A sum rule for light-by-light scattering can provide a testing ground of this conjecture.

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Vladimir Pascalutsa. 2011-10-26. Causality in the relativistic bound-state problem. https://doi.org/10.1007/s00601-012-0335-0

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