2016/12/08 by Nima Arkani–Hamed, Nima Arkani-Hamed, Laurentiu Rodina +1 · 70 citations
Physics and Astronomy · #Amplitude #Black Holes and Theoretical Physics #Gauge (firearms) #Gauge theory #Gravitational singularity #Locality #Mathematical physics #Particle physics #Particle physics theoretical and experimental studies #Philosophy #Physics #Quantum Chromodynamics and Particle Interactions #Quantum electrodynamics #Quantum mechanics #Scattering #Scattering amplitude #Theoretical physics #Unitarity #hep-th
paper · pdf · doi:10.1103/physrevlett.120.231602
published in Physical Review Letters 120(23), 231602 (American Physical Society) · 9 pages
arxiv created 2016/12/08 · openalex publication_date 2018/06/08 · arxiv updated 2018/06/13 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
We conjecture that the leading two-derivative tree-level amplitudes for gluons and gravitons can be derived from gauge invariance together with mild assumptions on their singularity structure. Assuming locality (that the singularities are associated with the poles of cubic graphs), we prove that gauge invariance in just n-1 particles together with minimal power counting uniquely fixes the amplitude. Unitarity in the form of factorization then follows from locality and gauge invariance. We also give evidence for a stronger conjecture: assuming only that singularities occur when the sum of a subset of external momenta go on shell, we show in nontrivial examples that gauge invariance and power counting demand a graph structure for singularities. Thus, both locality and unitarity emerge from singularities and gauge invariance. Similar statements hold for theories of Goldstone bosons like the nonlinear sigma model and Dirac-Born-Infeld by replacing the condition of gauge invariance with an appropriate degree of vanishing in soft limits.