通过nHz引力波探针利用SKAO探测宇宙学相变
Probing cosmological phase transitions with SKAO through nano-Hz gravitational-wave portal
AI总结：
该研究依托PTAs的nHz引力波背景证据，探讨利用SKAO探测早期宇宙相变的物理案例、模型及方法，以深化对早期宇宙粒子相互作用的理解，凸显SKAO在相关研究中的优势与互补性。
AI中文摘要：
近期脉冲星计时阵列（PTAs）在nHz频率处探测到随机引力波（GW）背景的证据，为利用平方公里阵列天文台（SKAO）探索宇宙演化历史及宇宙学相变提供了重要科学依据。这类宇宙学事件是早期宇宙物理学的核心研究对象，涉及量子色动力学（QCD） epoch附近的非平衡与弛豫现象，以及源自暗 sector或粒子物理标准模型之外其他现象的相关过程。这种新型引力波探针为粒子物理现象提供了互补探测途径，而这些现象至今未在粒子对撞机中被探测到，同时也能探测微扰理论之外的非平衡动力学基本方面及其宇宙学意义。本章旨在阐明与未来SKAO引力波测量密切相关的最具吸引力的物理案例、理论模型与方法，以及宇宙学场景。我们详细阐述这类测量如何深化我们对早期宇宙中粒子相互作用与剧烈过程的理解，并讨论相较于其他实验，SKAO在该研究领域可能具备的竞争优势与互补性。
英文摘要：
The recent evidence for a stochastic gravitational wave (GW) background at nano-Hz frequencies from pulsar timing arrays (PTAs) provides a strong science case for exploring cosmological histories and phase transitions at the Square Kilometer Array Observatory (SKAO). The latter cosmological events are of primary interest for physics of the early Universe associated with out-of-equilibrium and relaxation phenomena in the vicinity the quantum chromodynamics (QCD) epoch as well as those originating from dark sectors or other phenomena beyond the Standard Model of particle physics. Such a novel GW portal provides a complimentary access to particle physics phenomena that have so far escaped detection at particle colliders, and also probes fundamental aspects of out-of-equilibrium dynamics beyond the perturbation theory and their cosmological implications. This chapter aims at elucidating most interesting physics cases, theoretical models and approaches, as well as cosmological scenarios that are of particular relevance for future GW measurements at SKAO. We elaborate on how such measurements can deepen our understanding of particle interactions and violent processes in the early Universe, and discuss possible competitive advantages and complementarity of SKAO in this research compared to other experiments.
