论文标题
在光子或重力子中的所有3个粒子S-矩阵的分类
Classification of all 3 particle S-matrices quadratic in photons or gravitons
论文作者
论文摘要
我们明确地构建了每个运动学的每个运动学允许在每个维度上，以及每个选择的每个粒子 - $ p $ p $和photon-photon- $ p $ s-s-matrix，以及大量粒子$ p $的小组表示的每个选择。我们还明确构建了生成这些耦合中每一个的时空拉格朗日。在重力子的情况下，我们证明了这种拉格朗日始终涉及riemann张量的两个因素（衍生物），因此在衍生物中始终是第四或更高阶的。该结果验证了最近的预印\ cite {chowdhury：2019KAQ}中的一个假设之一，同时试图在局部经典理论中建立爱因斯坦树级S-matrix的刚性，并结合了界面粒子的集合。
We explicitly construct every kinematically allowed three particle graviton-graviton-$P$ and photon-photon-$P$ S-matrix in every dimension and for every choice of the little group representation of the massive particle $P$. We also explicitly construct the spacetime Lagrangian that generates each of these couplings. In the case of gravitons we demonstrate that this Lagrangian always involves (derivatives of) two factors of the Riemann tensor, and so is always of fourth or higher order in derivatives. This result verifies one of the assumptions made in the recent preprint \cite{Chowdhury:2019kaq} while attempting to establish the rigidity of the Einstein tree level S-matrix within the space of local classical theories coupled to a collection of particles of bounded spin.
