AI 中文总结
本文研究标量场与引力非最小耦合的单模暴胀扩展模型，计算两框架下的暴胀参数与谱指数，其数值结果符合Planck2018等观测数据，还为非最小耦合参数ξ提供新约束。
AI 中文摘要
我们在标量场与引力部分的非最小耦合框架下，研究单模宇宙学暴胀的扩展模型。在该设定中，我们将标量场与引力的非最小耦合作为能量-动量张量的唯一来源，不引入粒子物理标准模型（电弱理论）之外的新粒子。此场景下，该标量场的非最小耦合负责产生结构形成所需的扰动种子以及观测到的宇宙微波背景各向异性。我们分别在乔丹框架和爱因斯坦框架中计算暴胀参数，随后在爱因斯坦框架下研究慢滚参数的一阶和二阶原初谱指数。该模型的数值结果在模型参数空间的某些子空间内与Planck2018、BICEP/Keck联合数据集相符。通过考虑足够的暴胀量，我们估算非最小耦合参数ξ的取值，为该参数值找到合适的新约束条件。通过对比两个框架下暴胀可观测量的数值结果并与观测数据比较，我们讨论该框架中的框架问题。
英文摘要
We study an extension of the unimodular cosmological inflation in the context of the non-minimal coupling of a generic scalar field with gravitational sector. We consider the non-minimal coupling of the scalar field and gravity as the only source of energy-momentum tensor in this setup. Without introducing new particles other than those already existing in electroweak theory, the generic scalar field's non-minimal coupling is responsible for the generation of the seeds of perturbations for structure formation and the observed Cosmic Microwave Background anisotropies in this scenario. We calculate inflation parameters in both the Jordan and Einstein frames, and then we study primordial spectral indices for slow-roll parameters in Einstein's frame at the first and second orders. The numerical results of this model are consistent with the Planck2018 and BICEP/Keck joint data sets in some subspaces of the model parameters space. By considering a sufficient amount of inflation, we estimate the strength of the non-minimal coupling parameter, $ξ$, to find appropriate new constraints on the values of this parameter. By comparing the numerical values of the inflation observables in two frames and also with observation, we comment on the issue of frames in this framework.
Comments27 pages, 8 figures, 4 table
Journal refPhys. Dark Univ. 43, 101405 (2024)
DOI：10.1016/j.dark.2023.101405
