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arXiv · 2510.20156

Two-loop QCD Amplitudes from the Chiral Algebra Bootstrap

Anthony Morales
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Abstract

We show that the chiral algebra bootstrap, which computes form factors of twistorial theories, can help determine two-loop amplitudes in massless QCD. We give an $n$-gluon result for a previously unknown partial amplitude of the two-loop all-plus-helicity QCD amplitude by utilizing supersymmetry Ward identities and known chiral algebra bootstrap results. We then show that the full-color two-loop $n$-gluon amplitude of QCD with $n_f$ quark flavors can be obtained from certain two-loop form factors of twistorial theories and one-loop and tree-level amplitudes. Chiral algebra bootstrap results exist for these form factors when all gluons have positive helicities. Hence, the bootstrap simplifies the computation of these two-loop amplitudes by one loop level.

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Anthony Morales. 2025-10-23. Two-loop QCD Amplitudes from the Chiral Algebra Bootstrap. https://arxiv.org/abs/2510.20156

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