QCD Scattering Amplitudes and Prescriptive Unitarity
February 2026 Sérgio Carrôlo, Dmitry Chicherin, Johannes Henn, Qinglin Yang, Yang Zhang

Topics: Quantum Chromodynamics, Scattering Amplitudes, Unitarity

Usually bootstrap approaches start with a naive ansatz: match all possible functions with all possible pre-factors. Prescriptive unitarity gives us a guiding principle in which all the finite IR parts are completely fixed. We bootstrap the remaining free coefficients by imposing consistency with physical limits.

How gluon leading singularities discover curves on surfaces
December 2025 Sérgio Carrôlo, Carolina Figueiredo JHEP 07, 101 (2026)

Topics: Scattering Amplitudes, Leading Singularities, Surfaceology

We show that by gluing three-gluon amplitudes in QFT, we rediscover the combinatorial structure of curves on surfaces provided by surfaceology. Using some nice graphical arguments we can fix the expression for the exponents of closed curves.

Bootstrapping Six-Gluon QCD Amplitudes
October 2025 Sérgio Carrôlo, Dmitry Chicherin, Johannes Henn, Qinglin Yang, Yang Zhang Phys. Rev. Lett. 136, 181602 (2026)

Topics: QCD, Scattering Amplitudes, Bootstrap

A symbol-level bootstrap construction of planar two-loop six-gluon scattering amplitudes in QCD for the --++++ helicity configuration.

Symmetry and decoupling in multi-Higgs boson models
February 2021 Sergio Carrolo, Jorge C. Romão, João P. Silva, Francisco Vazão Phys. Rev. D 103, 075026 (2021)

Topics: BSM Phenomenology, Multi-Higgs Models

We show that there is a decoupling limit in N-Higgs-doublet-models iff the vacuum preserves the family symmetry of the lagrangian.