Is there Correlation between Fine Structure and Dark Energy Cosmic Dipoles?
Antonio Mariano, Leandros Perivolaropoulos
备注：
14 pages 11 figures (two column revtex). Aceepted in Phys. Rev. D (to appear). Significant extensions (mostly on section 4 on the theoretical model), added references, corrected typos. The data, updated mathematica and C program files used for the numerical analysis may be downloaded from http://leandros.physics.uoi.gr/defsdipoles
We present a detailed analysis (including redshift tomography) of the cosmic dipoles in the Keck+VLT quasar absorber and in the Union2 SnIa samples. We show that the fine structure constant cosmic dipole obtained through the Keck+VLT quasar absorber sample at $4.1σ$ level is anomalously aligned with the corresponding dark energy dipole obtained through the Union2 sample at $2σ$ level. The angular separation between the two dipole directions is $11.3^\circ \pm 11.8^\circ$. We use Monte Carlo simulations to find the probability of obtaining the observed dipole magnitudes with the observed alignment, in the context of an isotropic cosmological model with no correlation between dark energy and fine structure constant $α$. We find that this probability is less than one part in $10^6$. We propose a simple physical model (extended topological quintessence) which naturally predicts a spherical inhomogeneous distribution for both dark energy density and fine structure constant values. The model is based on the existence of a recently formed giant global monopole with Hubble scale core which also couples non-minimally to electromagnetism. Aligned dipole anisotropies would naturally emerge for an off-centre observer for both the fine structure constant and for dark energy density. This model smoothly reduces to \lcdm for proper limits of its parameters. Two predictions of this model are (a) a correlation between the existence of strong cosmic electromagnetic fields and the value of $α$ and (b) the existence of a dark flow on Hubble scales due to the repulsive gravity of the global defect core (`Great Repulser') aligned with the dark energy and $α$ dipoles. The direction of the dark flow is predicted to be towards the spatial region of lower accelerating expansion. Existing data about the dark flow are consistent with this prediction.
Prospect of Measuring the Cosmic Dipole by Associating Strongly Lensed Gravitational Waves with Galaxy Surveys
International Center for Theoretical Physics Asia-Pacific, University of Chinese Academy of Sciences（国际理论物理中心亚太，中国科学院大学）；Taiji Laboratory for Gravitational Wave Universe, University of Chinese Academy of Sciences（太极引力波宇宙实验室，中国科学院大学）
Probing cosmic anisotropy with gravitational waves as standard sirens
引力波（GW）作为一种标准的警报信号，直接由引力波波形确定光度距离，而不需要参考特定的宇宙学模型，其红移可以通过中子双星和大质量黑洞双星（MBHB）的GW事件等电磁对应物单独获得。为了考察标准海妖在多大程度上能够再现GW探测器典型配置的标准海妖事件模拟数据中所写的假定偶极各向异性，我们发现：（1）对于不同MBHB模型的激光干涉空间天线，在5年的观测中，在$3σ$置信水平（C.L.）并且偶极方向可以在$2σ$ C.L.处大致被约束在$20\%$周围，（2）对于不小于$0.03$标准siren事件的Einstein望远镜，在$3σ$ C. L.处，宇宙各向同性可以被排除.如果偶极振幅大于$0.06$，则偶极方向可以在$3σ$ C.L.处被约束在$20\%$内。（3）对于不小于$0.1$标准海妖事件的分赫兹干涉仪引力波天文台，在$3σ$ C. L.对于大于$0.03$的偶极振幅，偶极方向甚至可以在$10\%$ C.L.如果偶极振幅大于$0.07$。我们的工作显示了从标准的siren方法的约束能力对宇宙各向异性的前景。
Clustering properties of the CatWISE2020 quasar catalogue and their impact on the cosmic dipole anomaly
University of Oxford（牛津大学）；U.S. Naval Observatory（美国海军天文台）；University of Portsmouth（朴茨茅斯大学）；Tata Institute of Fundamental Research（塔塔基础研究所）；Sorbonne Université（索邦大学）
Analyzing the cosmic variance limit of remote dipole measurements of the cosmic microwave background using the large-scale kinetic Sunyaev Zel'dovich effect
The Cosmic Radio Dipole and Observer Effects in SKA all-sky surveys
Institute for Fundamental Physics of the Universe（宇宙基础物理研究所）；Royal Observatory Edinburgh（爱丁堡皇家天文台）；University of Oxford（牛津大学）；Yale University（耶鲁大学）；The University of Sydney（悉尼大学）；Guangdong Technion - Israel Institute of Technology（广东以色列理工学院）
Measuring cosmic dipole with the GRB luminosity-time relation
Aix Marseille Univ, Universite de Toulon, CNRS, CPT（艾克斯-马赛大学、土伦大学、法国国家科学研究中心、CPT）；Leung Center for Cosmology & Particle Astrophysics, National Taiwan University（台湾大学梁天文与粒子天体物理中心）；Aristotle University of Thessaloniki（塞萨洛尼基亚里士多德大学）；National Astronomical Observatory of Japan（日本国立天文台）；The Graduate University for Advanced Studies, SOKENDAI（综合研究大学院大学（SOKENDAI））；Space Science Institute（空间科学研究所）；Center for Astrophysics, University of Nevada, Las Vegas（内华达大学拉斯维加斯分校天体物理学中心）
Simulation-based tension quantification of the cosmic dipole
The University of Sydney（悉尼大学）；CSIRO Space and Astronomy（澳大利亚联邦科学与工业研究组织空间与天文部）；Cavendish Laboratory, Cambridge（剑桥卡文迪许实验室）；Kavli Institute for Cosmology, Cambridge（剑桥卡弗里宇宙学研究所）
Dipole Anisotropy as an Essential Qualifier for the Monopole Component of the Cosmic-Dawn Spectral Signature, and the Potential of Diurnal Pattern for Foreground Estimation
