Gravitational form factors of a kink in $1+1$ dimensional $\phi^4$ model

Hiroaki Ito; Masakiyo Kitazawa

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arXiv · 2302.08762

Gravitational form factors of a kink in $1+1$ dimensional $\phi^4$ model

Hiroaki Ito·Masakiyo Kitazawa

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Abstract

We calculate the one-loop correction to the distribution of energy-momentum tensor around a kink in $1+1$ dimensional $\phi^4$ model. We employ the collective coordinate method to eliminate the zero mode that gives rise to infrared divergence. The ultraviolet divergences are removed by vacuum subtraction and mass renormalization. We obtain an analytic result that is finite and satisfies the momentum conservation. The total energy of the kink obtained from the spatial integral of energy density reproduces the known result. Our result obtained on a finite space has a spatially-uniform term that is inversely proportional to the spatial length.

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Hiroaki Ito, Masakiyo Kitazawa. 2023-02-17. Gravitational form factors of a kink in $1+1$ dimensional $\phi^4$ model. https://arxiv.org/abs/2302.08762

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