论文标题
从自下而上的标准模型的弦乐完成
Stringy Completions of the Standard Model from the Bottom Up
论文作者
论文摘要
我们以$ 2 \ 2 $标量的$ 2 \ 2 $标量和仪表玻色子振幅学习一类树级安塞特式，灵感来自紫外线的启发。这些幅度表现出限制性，对于固定角度的高能量散射而言是指数柔软的，但是以大量残基的正延展性形式的单位性是一种非平凡的一致性条件。特别是，单位性迫使这些ansätze包括重力交换。在量规玻色散射的背景下，我们研究量规组$ SO（n）$和$ su（n）$。在四个维度中，量规组的界限为两个组的$ 24 $，并且以量规耦合的最大值出现$ g_ {ym}^2 = \ frac {2m_s^2} {2m_s^2} {m_p^2} $。在整数尺寸$ 5 \ leq d \ leq 10 $中，我们发现证据表明，量规组的最高允许等级$ r $与Swampland猜想$ r <26-D $一致。对于整数时空尺寸，该限制在$ su（n）$和$ so（n）$中都是相同的。我们还通过$ 2 \ 2 $ higgs散射研究标准模型的电动扇区，并找到与标准模型耦合，推定的弦乐量表和Planck量表有关的有趣约束。
We study a class of tree-level ansätze for $2\to 2$ scalar and gauge boson amplitudes inspired by stringy UV completions. These amplitudes manifest Regge boundedness and are exponentially soft for fixed-angle high energy scattering, but unitarity in the form of positive expandability of massive residues is a nontrivial consistency condition. In particular, unitarity forces these ansätze to include graviton exchange. In the context of gauge boson scattering, we study gauge groups $SO(N)$ and $SU(N)$. In four dimensions, the bound on the rank of the gauge group is $24$ for both groups, and occurs at the maximum value of the gauge coupling $g_{YM}^2 = \frac{2M_s^2}{ M_P^2} $. In integer dimensions $ 5\leq D \leq 10$ , we find evidence that the maximum allowed allowed rank $r$ of the gauge group agrees with the swampland conjecture $r < 26-D$. The bound is surprisingly identical for both $SU(N)$ and $SO(N)$ in integer spacetime dimensions. We also study the electroweak sector of the standard model via $2 \to 2$ Higgs scattering and find interesting constraints relating standard model couplings, the putative string scale, and the Planck scale
