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arXiv · 2507.22103

Hamiltonian Truncation of Large $N_f$ QED and Large $N$ Vector-like Theories in $d=2+1$

A. Liam Fitzpatrick·Anastasiia Novikova·Noah Ring
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Abstract

We consider a general class of large $N$ vector-like theories in $d=2+1$ in a Hamiltonian approach. We show that by using lightcone quantization and the $N\to\infty$ limit, we can diagonalize the Hamiltonian exactly and construct the eigenstates, spectral density, S-matrix, and form factors for the theory. For concreteness, we mainly focus on QED$_3$ at large $N_f$ as an explicit example. We comment on extending the approach to finite $N$ calculations.

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A. Liam Fitzpatrick, Anastasiia Novikova, Noah Ring. 2025-07-29. Hamiltonian Truncation of Large $N_f$ QED and Large $N$ Vector-like Theories in $d=2+1$. https://arxiv.org/abs/2507.22103

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