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arXiv · 2003.08405

Exploring Hamiltonian Truncation in $\bf{d=2+1}$

Joan Elias Miro·Edward Hardy
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Abstract

We initiate the application of Hamiltonian Truncation methods to solve strongly coupled QFTs in $d=2+1$. By analysing perturbation theory with a Hamiltonian Truncation regulator, we pinpoint the challenges of such an approach and propose a way that these can be addressed. This enables us to formulate Hamiltonian Truncation theory for $\phi^4$ in $d=2+1$, and to study its spectrum at weak and strong coupling. The results obtained agree well with the predictions of a weak/strong self-duality possessed by the theory. The $\phi^4$ interaction is a strongly relevant UV divergent perturbation, and represents a case study of a more general scenario. Thus, the approach developed should be applicable to many other QFTs of interest.

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Joan Elias Miro, Edward Hardy. 2020-03-18. Exploring Hamiltonian Truncation in $\bf{d=2+1}$. https://doi.org/10.1103/physrevd.102.065001

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