论文标题
具有不同音速的标量的单位性关系和单位性界限
Unitarity relation and unitarity bounds for scalars with different sound speeds
论文作者
论文摘要
由标量调整的重力激励，我们考虑了一种理论，该理论包含具有不同声速的无质量标量字段。我们得出了$ 2 \ 2 $散射的部分波幅度的单位关系，并具有明确的公式，用于两粒子中间状态的贡献。利用这些关系，我们在最普遍的情况下以及文献中考虑单位音速的情况下都获得了单位性界限。这些界限可用于估计相关EFT的强耦合量表。我们通过在两个具有不同声速的标量字段的简单模型中对耦合中的第一个非平凡顺序进行明确计算来说明我们的单位性关系。
Motivated by scalar-tensor gravities, we consider a theory which contains massless scalar fields with different sound speeds. We derive unitarity relations for partial wave amplitudes of $2 \to 2$ scattering, with explicit formulas for contributions of two-particle intermediate states. Making use of these relations, we obtain unitarity bounds both in the most general case and in the case considered in literature for unit sound speed. These bounds can be used for estimating the strong coupling scale of a pertinent EFT. We illustrate our unitarity relations by explicit calculation to the first non-trivial order in couplings in a simple model of two scalar fields with different sound speeds.
