International Journal of Modern Physics A ( IF 1.4 ) Pub Date : 2021-09-02 Katsuki Tomita
We extend a classically scale invariant model where the electroweak symmetry breaking is triggered by the dynamical chiral symmetry breaking in a hidden QCD sector, and a real singlet scalar mediates these two sectors. Our model can explain cosmic inflation without unitarity violation in addition. Slow-roll inflation occurs along a valley in scalar potential. In the original model, the coupling between the Higgs field and is always negative and therefore, the potential has its valleys in - mixed directions. For large value of the top Yukawa coupling , the potential along the valley becomes negative since the Higgs quartic coupling becomes negative at inflationary scale. Then slow-roll inflation cannot occur. For inflation to definitely occur, we render the coupling positive at inflationary scale and consider the -inflation case. This is achieved by introducing a new singlet scalar with the large coupling to . By this extension, can also always be positive, and we consider this case as the simplest case. We consider inflation with the nonminimal coupling between and gravity. Although is large such as , unitarity is not violated since couplings between and other fields are sufficiently small. is odd under a new symmetry not to mix with regardless of largeness of . Because of this symmetry, may have its relic abundance comparable with the observational value of the dark matter relic abundance. However, the spin-independent elastic cross-section of exceeds the observational bound cm2. Hence, we impose the resonance condition and reduce to much smaller than . Constraints from the electroweak scale physics and inflationary scale physics are much strong, and the allowed parameter space is very narrow.
中文翻译:
基于经典尺度不变扩展标准模型的通货膨胀
我们扩展了一个经典的尺度不变模型,其中电弱对称破坏是由隐藏 QCD 扇区中的动态手征对称破坏触发的,以及一个真正的单线态标量 中介这两个部门。此外,我们的模型可以解释宇宙膨胀而不会违反幺正性。缓慢的膨胀发生在标量势的谷底。在原始模型中,联轴器 希格斯场之间 和 总是负面的,因此,潜力在 ——混合方向。大值顶级汤川联轴器,由于希格斯四次耦合,沿谷的电位变为负 在通胀规模上变为负值。那么慢速通胀就不会发生。为了肯定会发生通货膨胀,我们渲染了耦合 在通胀规模上为正,并考虑 - 通货膨胀情况。这是通过引入新的单线态标量来实现的 大联轴器 到 . 通过这个扩展,也可以总是正数,我们认为这种情况是最简单的情况。我们考虑非最小耦合的通货膨胀 之间 和重力。虽然 大如 ,不违反单一性,因为之间的耦合 和其他领域足够小。 在新的对称性下是奇数 不可混用 不管有多大 . 由于这种对称性, 可能有它的遗迹丰富 与观测值相当 暗物质遗迹的丰度。然而,与自旋无关的弹性截面 的 超出观察范围 厘米2。因此,我们强加共振条件 并减少 远小于 . 来自电弱尺度物理和暴胀尺度物理的约束非常强,并且允许的参数空间非常狭窄。