Collaborative Research: Experimental General Relativity using Radio Interferometry of a Black Hole Photon Ring

合作研究：利用黑洞光子环射电干涉测量的实验广义相对论

• 批准号: 2307887
• 负责人: Michael Johnson
• 金额: $ 26.82万
• 依托单位: Smithsonian Institution Astrophysical Observatory
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2026-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2307887&HistoricalAwards=false
• 关键词: Collaborative; Research; Experimental; General; Relativity

In April 2019, the Event Horizon Telescope (EHT) collaboration released the first images of a black hole, a breakthrough result that has since prompted a flurry of new theoretical studies. These have revealed that black hole images carry distinctive relativistic signatures, which are embedded within a bright, narrow ring encircling the black hole. A research collaboration between the Smithsonian Institution Astrophysical Observatory and Vanderbilt University will explore the fundamental properties of this “photon ring,” will show how it can be studied using radio interferometry, and will determine the properties of a black hole’s spacetime that can be probed with observations. These researchers have already established the photon ring as a universal prediction of General Relativity: it is a matter-independent effect caused by the extreme bending of light near the event horizon of the black hole. Indeed, Einstein’s theory predicts that Kerr black holes can deflect light rays to such a degree that they circumnavigate the black hole—possibly several times—before eventually reaching distant observers. Black hole imaging is a nascent field with an already global reach and intense public engagement. As part of this project, the investigators will engage the public with this research through the development of new classroom activities for neurodiverse and special education students as well as novel art exhibits conveying the elegance and mysteries hidden within black hole images.During this project, scientists will study the information that the orbiting light encodes about the geometry of the black hole’s spacetime, as well as the astrophysical conditions of the surrounding plasma and electromagnetic fields. This will combine the pursuit of two parallel yet interconnected lines of work: 1) On the theory side, analysis of simple models will build intuition and provide insight into interferometric properties of the photon ring, while development of time- dependent, “slow-light” photon ring models with variability informed by plasma astrophysics will clarify how the simple models relate to the complex structure in a realistic accretion flow model; and 2) On the observational side, the development of progressively more elaborate statistical inference tools and numerical simulations will utilize these models to extract increasingly precise knowledge of supermassive black hole astrophysics from interferometric data, culminating in formal posteriors for the mass, spin, and inclination of both M87* and Sgr A* from EHT data.Two major research outputs of this project will be the comprehensive characterization of the unique photon ring signatures that can be targeted with VLBI (very-long-baseline interferometry), and model-agnostic estimates of mass, spin, and inclination for M87* and Sgr A* using current EHT data.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

2019年4月，活动Horizo​​n Telescope（EHT）合作发布了黑洞的第一张图像，这是一个突破性的结果，此后引发了一系列新的理论研究。这些揭示了黑洞图像带有独特的相对主义特征，这些签名嵌入了包围黑洞的明亮，狭窄的环中。史密森学会天体天文台和范德比尔特大学之间的研究合作将探讨该“光子环”的基本属性，将显示如何使用无线电干扰来研究它，并将确定可以通过观察值探测的黑洞时空的属性。这些研究人员已经建立了光子环作为一般相对论的普遍预测：这是由于黑洞事件范围附近的光的极端弯曲而引起的无关效应。的确，爱因斯坦的理论预测，克尔黑洞可以将光线击败至一定程度，以至于最终到达遥远的观察者之前，它们会绕过黑洞（可能是几次）。黑洞成像是一个新生的领域，已经具有全球性的影响力和强烈的公众参与。作为该项目的一部分，调查人员将通过开发针对神经多样性和特殊教育学生的新课堂活动以及新的艺术展览来传达隐藏在黑洞图像中的优雅和神秘的新颖艺术。在此项目中，科学家将研究轨道的信息，这些信息将编码有关黑洞的几何形状以及黑洞的几何形状，以及黑洞的几何形状，以及周围的天文学和周围的天文学的信息。 This will combine the pursuit of two parallel yet interconnected lines of work: 1) On the theory side, analysis of simple models will build intuition and provide insight into interference properties of the photo ring, while development of time-dependent, “slow-light” photon ring models with variability informed by plasma astrophysics will clarify how the simple models relate to the complex structure in a realistic accretion flow model;和2）在观察方面，从干涉数据中提取了对超级质量黑洞天体物理学的逐渐逐渐详细的统计推理工具和数值模拟的开发，从而在形式的后代中提取了超级质量的黑洞天体物理学的知识，从而在正式的后代中提取了M87*和SGR A的群众倾向和倾向的构图。 photon ring signatures that can be targeted with VLBI (very-long-baseline interference), and model-agnostic estimates of mass, spin, and inclination for M87* and Sgr A* using current EHT data.This award reflects NSF's statutory mission and has been deemed worthy of support Through evaluation using the Foundation's intellectual merit and broader impacts review criteria.