Institut de physique theorique, Universite Paris Saclay, CEA, CNRS, F-91191 Gif-sur-Yvette, France.
Phys Rev Lett. 2019 Feb 22;122(7):071601. doi: 10.1103/PhysRevLett.122.071601.
We prove that soft theorems uniquely fix tree-level scattering amplitudes in a wide range of massless theories, including Yang-Mills, gravity, the nonlinear sigma model, Dirac-Born-Infeld, dilaton effective theories, extended theories like the NLSM⊕ϕ^{3} (nonlinear sigma model ϕ^{3}), as well as some higher derivative corrections to these theories. We conjecture the same is true even when imposing more general soft behavior, simply by assuming the existence of soft operators, or by imposing gauge invariance or the Adler zero only up to a finite order in soft expansions. Besides reproducing known amplitudes, this analysis reveals a new higher order correction to the NLSM and two interesting facts: the subleading theorem for the dilaton, and the subsubleading theorem for DBI follow automatically from the more leading theorems. These results provide motivation that asymptotic symmetries contain enough information to fully fix a holographic S matrix.
我们证明，软定理在广泛的无质量理论中唯一地确定了树图散射振幅，包括杨-米尔斯理论、引力理论、非线性西格玛模型、狄拉克-博恩-英菲尔德理论、膨胀子有效理论、NLSM⊕ϕ^{3}（非线性西格玛模型ϕ^{3}）等扩展理论，以及这些理论的一些更高阶导数修正。我们推测，即使在施加更一般的软行为时，这种情况也是如此，只需假设软算符的存在，或仅在软展开的有限阶次上假设规范不变性或阿德勒零点即可。除了再现已知的振幅外，这种分析还揭示了 NLSM 的一个新的高阶修正以及两个有趣的事实：膨胀子的次-leading 定理以及 DBI 的次次-leading 定理自动来自于更 leading 的定理。这些结果提供了动机，表明渐近对称性包含足够的信息来完全确定全息 S 矩阵。
