标题： 引力诱导量子二次引力中费米尺度的出现 显示英文标题

标题： Gravity-induced emergence of the Fermi scale in quantum quadratic gravity

摘要： 在渐近安全性框架内，我们研究了在希格斯场存在的情况下量子二次引力理论，该希格斯场被认为与真空不可分离。 该理论流向一个高能不动点，在此不动点处希格斯场与引力强耦合，其势能是对称的，并且二次韦尔曲率耦合较大。 后者使得幽灵引力子成为一种不稳定的高质量共振态，这使得理论在李-威类型理论的意义上保持幺正性。 此外，如果标量引力子是快子，则会存在一个低能不动点，在此不动点处快子凝聚导致新的稳定真空。 在这个不动点处，对称性被打破，费米尺度出现，并且希格斯场的行为是经典的（不受引力相互作用的影响）。 在紫外尺度下，引力完全是二次的；而在费米尺度下，它是线性的，并且在中间区域两种贡献都是相关的。 因此，在费米尺度下，通过幽灵不稳定性以及快子凝聚，二次曲率场消失，从而产生爱因斯坦引力和电弱相变。 显示英文摘要

摘要： In the framework of asymptotic safety, we study quantum quadratic gravity in the presence of the Higgs field considered as non-separable from the vacuum. The theory flows to a high energy fixed point where the Higgs field is strongly coupled to gravity, its potential is symmetric, and the quadratic Weyl curvature coupling is large. The latter renders the ghost graviton an unstable high mass resonance which renders unitarity in the spirit of Lee-Week type theories. Furthermore, if the scalar graviton is tachyonic then there will be a low energy fixed point where tachyonic condensation leads to a new stable vacuum. At this fixed point the symmetry breaks and the Fermi scale emerges, and the behavior of the Higgs field is classical (not influenced by gravitational interaction). Gravity at the UV scale is purely quadratic whereas at the Fermi scale it is linear, and in the intermediate region both contributions are relevant. Thus, at the Fermi scale the quadratic curvature fields disappear through the ghost instability and tachyon condensation, giving rise to Einstein gravity and the electroweak phase transition.