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 S 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 − λHS between the Higgs field H and S is always negative and therefore, the potential has its valleys in H-S mixed directions. For large value of the top Yukawa coupling yt, the potential along the valley becomes negative since the Higgs quartic coupling λH becomes negative at inflationary scale. Then slow-roll inflation cannot occur. For inflation to definitely occur, we render the coupling − λHS positive at inflationary scale and consider the S-inflation case. This is achieved by introducing a new singlet scalar η with the large coupling λHη to H. By this extension, λH can also always be positive, and we consider this case as the simplest case. We consider inflation with the nonminimal coupling ξS between S and gravity. Although ξS is large such as ξS ≃𝒪(103), unitarity is not violated since couplings between S and other fields are sufficiently small. η is odd under a new symmetry Z2 not to mix with H regardless of largeness of λHη. Because of this symmetry, η may have its relic abundance Ωηĥ2 comparable with the observational value Ωobsĥ2 ≃ 0.12 of the dark matter relic abundance. However, the spin-independent elastic cross-section σSIη of η exceeds the observational bound σSIobs ∼𝒪(10−47) cm². Hence, we impose the resonance condition mη ≃ mS/2 and reduce Ωηĥ2 to much smaller than Ωobsĥ2. 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：

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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尺度不变模型，其中电弱对称性破缺是由隐藏的 QCD 扇区中的动态手征对称破缺触发的，以及一个真正的单重态标量小号调解这两个部门。我们的模型可以解释宇宙膨胀而不会另外违反统一性。缓慢滚动的通货膨胀沿着标量势的山谷发生。在原始模型中，联轴器 - λH小号希格斯场之间H和小号总是负的，因此，潜力有它的谷底H-小号混合方向。用于大值顶部汤川联轴器是的吨，由于希格斯四次耦合，沿谷的势变为负λH在通货膨胀规模上变为负数。这样就不会发生慢速通胀。为了确定暴胀发生，我们渲染耦合 - λH小号通胀规模为正，并考虑小号-通货膨胀案例。这是通过引入一个新的单线态标量来实现的η与大型联轴器λHη到H. 通过这个扩展，λH也可以总是为正的，我们认为这种情况是最简单的情况。我们考虑膨胀与非最小耦合ξ小号之间小号和重力。虽然ξ小号很大比如ξ小号 ≃𝒪(103)，不违反统一性，因为之间的耦合小号和其他领域足够小。η在新的对称性下是奇数Z2不要混合H不论大小λHη. 由于这种对称性，η可能有它的遗迹丰富ΩηH2与观测值相当Ω观测值H2 ≃ 0.12暗物质遗迹丰度。然而，与自旋无关的弹性截面σSIη的η超出观察范围σSI观测值 ～𝒪(10-47)厘米²。因此，我们强加了共振条件米η ≃ 米小号/2并减少ΩηH2远小于Ω观测值H2. 来自电弱尺度物理和暴胀尺度物理的约束非常强，允许的参数空间非常狭窄。