An attractive $\phi^4$ theory in light-front coordinates

O. Teoman Turgut; Gökhan Yalnız

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arXiv · 1812.09555

An attractive $\phi^4$ theory in light-front coordinates

O. Teoman Turgut·Gökhan Yalnız

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Abstract

We study an attractive $\phi^4$ interaction using Tamm-Dancoff truncation with light-front coordinates in $3+1$ dimensions. The truncated theory requires a coupling constant renormalization, we compute its $\beta$ function non-perturbatively, show that the model is asymptotically free, and find the corresponding Callan-Symanzik equations. The model supports bound states, we find the wave function for the ground state of the two-particle sector. We also give a bound for the $N$-particle ground state energy within a mean field approximation, including the corresponding result for the case of $2+1$ dimensions where the model does not require renormalization.

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O. Teoman Turgut, Gökhan Yalnız. 2018-12-22. An attractive $\phi^4$ theory in light-front coordinates. https://arxiv.org/abs/1812.09555

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