Scalar dark energy models and scalar–tensor gravity:theoretical explanations for the accelerated expansion of the present Universe  

作　　者：Peixiang Ji Lijing Shao 

机构地区：[1]Department of Astronomy,School of Physics,Peking University,Beijing 100871,China [2]Kavli Institute for Astronomy and Astrophysics,Peking University,Beijing 100871,China [3]National Astronomical Observatories,Chinese Academy of Sciences,Beijing 100012,China

出　　处：《Communications in Theoretical Physics》2024年第10期158-187,共30页理论物理通讯（英文版）

基　　金：supported by the National Natural Science Foundation of China(11991053);Beijing Natural Science Foundation(1242018);National SKA Program of China(2020SKA0120300);Max Planck Partner Group program funded by the Max Planck Society;High-Performance Computing Platform of Peking University。

摘　　要：The reason for the present accelerated expansion of the Universe stands as one of the most profound questions in the realm of science,with deep connections to both cosmology and fundamental physics.From a cosmological point of view,physical models aimed at elucidating the observed expansion can be categorized into two major classes:dark energy and modified gravity.We review various major approaches that employ a single scalar field to account for the accelerating phase of our present Universe.Dynamic system analysis was employed in several important models to find cosmological solutions that exhibit an accelerating phase as an attractor.For scalar field models of dark energy,we consistently focused on addressing challenges related to the fine-tuning and coincidence problems in cosmology,as well as exploring potential solutions to them.For scalar–tensor theories and their generalizations,we emphasize the importance of constraints on theoretical parameters to ensure overall consistency with experimental tests.Models or theories that could potentially explain the Hubble tension are also emphasized throughout this review.

关 键 词：dark energy modified gravity QUINTESSENCE dynamic system COSMOLOGY 

分 类 号：P159[天文地球—天文学]