论文标题
重力阳性界限
Gravitational positivity bounds
论文作者
论文摘要
我们研究了振幅的雷格行为，研究了在无质量重力的情况下的阳性界限的有效性。在此假设下，有问题的$ t $ channel极是通过分散关系中振幅的假想部分的紫外线积分取消的，这为阳性范围带来了有限的校正。我们发现，允许使用具有“错误”符号的低能有效场理论（EFT）。允许的违规数量由Regge行为决定。 $ m _ {\ rm pl}^{ - 2}α'$抑制了这种违规行为，其中$α'$是reggeization的规模。这意味着只有当EFT的截止量表远低于重新化的量表时，才能应用阳性界限。然后，我们在单循环水平上获得标量调整器EFT上的阳性边界。还讨论了我们结果对退化高阶标量调整（DHOST）理论的含义。
We study the validity of positivity bounds in the presence of a massless graviton, assuming the Regge behavior of the amplitude. Under this assumption, the problematic $t$-channel pole is canceled with the UV integral of the imaginary part of the amplitude in the dispersion relation, which gives rise to finite corrections to the positivity bounds. We find that low-energy effective field theories (EFT) with "wrong" sign are generically allowed. The allowed amount of the positivity violation is determined by the Regge behavior. This violation is suppressed by $M_{\rm pl}^{-2}α'$ where $α'$ is the scale of Reggeization. This implies that the positivity bounds can be applied only when the cutoff scale of EFT is much lower than the scale of Reggeization. We then obtain the positivity bounds on scalar-tensor EFT at one-loop level. Implications of our results on the degenerate higher-order scalar-tensor (DHOST) theory are also discussed.
