2021/11/24 by Henriette Elvang, Elvang, Henriette, Matthew Dominique Mitchell +1
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #FOS: Physical sciences #High Energy Physics - Theory (hep-th) #Particle physics theoretical and experimental studies
paper · pdf · doi:10.48550/arxiv.2111.12686
openalex publication_date 2021/11/24 · openalex created_date 2022/05/05 · openalex updated_date 2026/08/01
We use on-shell amplitude methods to systematically analyze the possibility of extended supersymmetry for 4d Galileon models, expanding on previous N=1 results. Assuming spins ≤ 1, we prove that there exists no N=4 supersymmetric extension of any 4d Galileons. Thus the Galileons cannot be part of the effective action of a single flat maximally supersymmetric D3-brane, and that explains why such terms do not appear in the α'-expansion of the abelian open superstring amplitude. For N=2 Galileons, we show that the complex scalar Z = ϕ+ i χ of the vector supermultiplet cannot have ϕ and χ both enjoy enhanced shift symmetry; instead, χ can at best be an R-axion with constant shift symmetry. Using the soft bootstrap, we demonstrate that the quartic DBI-Galileon is incompatible with N=2 supersymmetry. A similar analysis performed at 7-point shows that a 2-parameter family of N=2 supersymmetric quintic Galileons coupled with DBI passes the soft bootstrap. Finally, we show how supersymmetric coup\-lings between Galileons and gravitons arise in generalizations of our constructions, and we conclude with a discussion of Galileons and DBI-Galileons in the context of UV-completability vs.~the Swampland.