Banca de QUALIFICAÇÃO: GUSTAVO BISPO

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
DISCENTE : GUSTAVO BISPO
Data: 28/09/2026
HORA: 14:00
LOCAL: Sala 305 do Bloco B do Campus de Santo André da Universidade Federal do ABC
TÍTULO:

Computing N-photon amplitudes in effective field theories

PÁGINAS: 50
RESUMO:

The act of integrating out massive degrees of freedom in a quantum field theory generates an infinite tower of higher-dimensional operators. The resulting Lagrangian is what we denote as an Effective Field Theory (EFT) for the remaining particles. It is well known that EFTs fail to satisfy recursive constructibility statements for amplitudes, by virtue of their pole-free contributions, invisible to on-shell factorization. In this work, we start from a self-dual decomposition of the field strength for photons, with which we are able to reorganize the EFT Lagrangian through a functional formalism, such that all contact contributions are resummed into an effective helicity vertex. Amplitudes coming from these vertices are given by a single Hafnian over a matrix built from spinor brackets. These amplitudes, denoted contact amplitudes, are the building blocks for all other higher-point amplitudes, obtained by factorization on poles, in a manner similar to the way MHV amplitudes are used in CSW recursion. With our method, we are able to construct all N-photon amplitudes in a generic EFT, up to N=8, as a combination of Hafnians. We also provide a proof that electromagnetic duality produces theories with helicity-conserving amplitudes, a property made manifest by the resummed contact Lagrangian.

MEMBROS DA BANCA:
Presidente - Interno ao Programa - 1676798 - CELSO CHIKAHIRO NISHI
Membro Titular - Examinador(a) Interno ao Programa - 3065679 - BRENO MARQUES GONCALVES TEIXEIRA
Membro Titular - Examinador(a) Externo ao Programa - 1156317 - ADRIANO LANA CHERCHIGLIA
Membro Suplente - Examinador(a) Externo à Instituição - CÉSAR AUGUSTO BERNARDES - UNESP