arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 2005.11171gr-qc
收藏

Horndeski理论对暗能量模型的限制

Constraints on dark energy models from the Horndeski theory

Bilguun Bayarsaikhan, Seoktae Koh, Enkhbat Tsedenbaljir, Gansukh Tumurtushaa

摘要:

根据宇宙学的观测结果,我们研究了Horndeski引力理论中的暗能量模型。特别地,我们考虑了具有标量场的导数自相互作用和标量场与引力的导数耦合的宇宙学模型。我们选择的自相互作用项具有标量场的指数函数,具有正和负指数。对于具有正指数的函数,我们的结果表明,导数自相互作用项在晚时宇宙中起着重要的作用。另一方面,为了再现正确的宇宙历史,标量场和引力之间的导数耦合必须在辐射主导阶段占主导地位。然而,在目前的宇宙中,这种耦合的重要性被认为是微不足道的,因为它随着时间的推移急剧下降。此外,我们的模型估计的引力波的传播速度是在观测范围内,我们的模型满足观测约束的暗能量状态方程。

英文摘要:

In light of the cosmological observations, we investigate dark energy models from the Horndeski theory of gravity. In particular, we consider cosmological models with the derivative self-interaction of the scalar field and the derivative coupling between the scalar field and gravity. We choose the self-interaction term to have an exponential function of the scalar field with both positive and negative exponents. For the function that has a positive exponent, our result shows that the derivative self-interaction term plays an important role in the late-time universe. On the other hand, to reproduce the right cosmic history, the derivative coupling between the scalar field and gravity must dominate during the radiation-dominated phase. However, the importance of such a coupling in the present universe found to be negligible due to its drastic decrease over time. Moreover, the propagation speed of gravitational waves estimated for our model is within the observational bounds, and our model satisfies the observational constraints on the dark energy equation of state.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑