Theoretical developments in the SMEFT at dimension-8 and beyond

Simone Alioli; Radja Boughezal; Weiguang Cao; Mikael Chala; Álvaro Díaz-Carmona; Supratim Das Bakshi; Gauthier Durieux; Lukáš Gráf; Guilherme Guedes; Brian Quinn Henning; Teppei Kitahara; Hao-Lin Li; Xiaochuan Lu; Camila S. Machado; Adam Martin; Tom Melia; Emanuele Mereghetti; Hitoshi Murayama; Christopher W. Murphy; Jasper Roosmale Nepveu; Sridip Pal; Frank Petriello; Yael Shadmi; Jing Shu; Yaniv Weiss; Ming-Lei Xiao; Jiang-Hao Yu

arXiv · 2203.06771

Theoretical developments in the SMEFT at dimension-8 and beyond

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Abstract

In this contribution to the Snowmass 2021 process we review theoretical developments in the Standard Model Effective Field Theory (SMEFT) with a focus on effects at the dimension-8 level and beyond. We review the theoretical advances that led to the complete construction of the operator bases for the dimension-8 and dimension-9 SMEFT Lagrangians. We discuss the possibility of obtaining all-orders results in the $1/\Lambda$ expansion for certain SMEFT observables as well as the current status of renormalization group running and implications for positivity, and briefly present the on-shell approach to constructing SMEFT amplitudes. Finally we present several new phenomenological effects that first arise at dimension-8 and discuss the impact of these terms on experimental analyses.

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Simone Alioli, Radja Boughezal, Weiguang Cao, Mikael Chala, Álvaro Díaz-Carmona, Supratim Das Bakshi, Gauthier Durieux, Lukáš Gráf, Guilherme Guedes, Brian Quinn Henning, Teppei Kitahara, Hao-Lin Li, Xiaochuan Lu, Camila S. Machado, Adam Martin, Tom Melia, Emanuele Mereghetti, Hitoshi Murayama, Christopher W. Murphy, Jasper Roosmale Nepveu, Sridip Pal, Frank Petriello, Yael Shadmi, Jing Shu, Yaniv Weiss, Ming-Lei Xiao, Jiang-Hao Yu. 2022-03-13. Theoretical developments in the SMEFT at dimension-8 and beyond. https://arxiv.org/abs/2203.06771

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