High-precision calculations in strongly coupled quantum field theory with next-to-leading-order renormalized Hamiltonian Truncation

2017/06/30 by Joan Elias Miró, Joan Elias-Miro, Slava Rychkov +2 · 55 citations
Physics and Astronomy · #Black Holes and Theoretical Physics #Cutoff #Hamiltonian (control theory) #Mathematical physics #Physics #Physics of Superconductivity and Magnetism #Quantum Chromodynamics and Particle Interactions #Quantum mechanics #Quartic function #Renormalization #Renormalization group #Theoretical physics #Truncation (statistics) #cond-mat.str-el #hep-th

paper · pdf · doi:10.1007/jhep10(2017)213

published in Journal of High Energy Physics 2017(10) (Springer Nature) · 8 pages, 4 figures; v2: published version

openalex publication_date 2017/10/01 · arxiv created 2017/12/15 · arxiv updated 2017/12/19 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06

Abstract

Hamiltonian Truncation (a.k.a. Truncated Spectrum Approach) is an efficient numerical technique to solve strongly coupled QFTs in d = 2 spacetime dimensions. Further theoretical developments are needed to increase its accuracy and the range of applicability. With this goal in mind, here we present a new variant of Hamiltonian Truncation which exhibits smaller dependence on the UV cutoff than other existing implementations, and yields more accurate spectra. The key idea for achieving this consists in integrating out exactly a certain class of high energy states, which corresponds to performing renormalization at the cubic order in the interaction strength. We test the new method on the strongly coupled two-dimensional quartic scalar theory. Our work will also be useful for the future goal of extending Hamiltonian Truncation to higher dimensions d ≥ 3.

Citations

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