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arXiv · 1612.09331

Light-front $\phi_2^4$ theory with sector-dependent mass

S. S. Chabysheva·J. R. Hiller
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Abstract

As an extension of recent work on two-dimensional light-front $\phi^4$ theory, we implement Fock-sector dependence for the bare mass. Such dependence should have important consequences for the convergence of nonperturbative calculations with respect to the level of Fock-space truncation. The truncation forces the self-energy corrections to be sector-dependent; in particular, the highest sector has no self-energy correction. Thus, the bare mass can be considered sector dependent as well. We find that, although higher Fock sectors have a larger probability, the mass of the lightest state and the value of the critical coupling are not significantly affected. This implies that coherent states or the light-front coupled-cluster method may be required to properly represent critical behavior.

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S. S. Chabysheva, J. R. Hiller. 2016-12-29. Light-front $\phi_2^4$ theory with sector-dependent mass. https://doi.org/10.1103/physrevd.95.096016

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