Extending single-minus amplitudes to gravitons
New research shows that single-minus graviton amplitudes, previously thought to vanish, are nonzero under specific half-collinear kinematic conditions.Summary
This preprint details research extending recent findings about scattering amplitudes in gauge theory (gluons) to quantum gravity, focusing on gravitons. Specifically, the authors analyze single-minus amplitudes, where one graviton has negative helicity and the others positive. Textbook physics suggests these amplitudes should vanish at tree level, but the paper demonstrates they are nonzero when particle momenta satisfy a special half-collinear alignment. These non-vanishing amplitudes are described as well-defined mathematical distributions supported on a restricted momentum space region. The derivation relies on symmetry principles and recursion relations, and the results connect to the infinite-dimensional "w-(1+∞)" symmetry discovered by Penrose, which is expected to be central to quantizing gravity. The work was significantly aided by GPT-5.2 Pro, which helped construct the gravitational amplitudes based on the prior gluon result, shifting the research effort towards verification and formal write-up.
(Source：OpenAI)