论文标题
Graviton Exchange中无质量的积极性
Massless Positivity in Graviton Exchange
论文作者
论文摘要
我们为散射幅度的阳性界限制定了阳性，包括交换无质量颗粒。我们通过分散关系概括了标准构造，以包括马尔德斯坦变量$ s $的复杂平面中沿真实轴切割的分支。通常，这些界限的有效性要求取消振幅的差异，与$ t^{ - 1} $和$ \ log（t）$成比例。我们表明，如果人们在文献中以前提出的高能量以高能量低于普朗克量表的振幅的振幅行为，并且幅度的混凝土紫外线行为是由IR差异的结构唯一确定的，那么这是可能的。因此，我们通过包括一个子领导对数项来扩展先前的结果，我们表明这是通用的。我们在这里提出的边界具有约束非常通用的修饰重力模型和物质EFT的模型，并结合了引力。
We formulate Positivity Bounds for scattering amplitudes including exchange of massless particles. We generalize the standard construction through dispersion relations to include the presence of a branch cut along the real axis in the complex plane for the Maldestam variable $s$. In general, validity of these bounds require the cancellation of divergences in the forward limit of the amplitude, proportional to $t^{-1}$ and $\log(t)$. We show that this is possible in the case of gravitons if one assumes a Regge behavior of the amplitude at high energies below the Planck scale, as previously suggested in the literature, and that the concrete UV behaviour of the amplitude is uniquely determined by the structure of IR divergences. We thus extend previous results by including a sub-leading logarithmic term, which we show to be universal. The bounds that we present here have the potential of constraining very general models of modified gravity and EFTs of matter coupled to gravitation.
