Séminaire / Seminar GReCO |
| « What can we infer from black hole images? » |
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Frederic Vincent |
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The recent Event Horizon Telescope (EHT) millimeter image of the vicinity
of the supermassive compact object M87* at the center of the galaxy M87 is a breakthrough. It is important to investigate what can and what cannot be inferred from such images. In this talk I will discuss a simple geometric model of the region of the accretion flow immediately surrounding M87*. I will use this model to discuss the highly-lensed features of EHT-like images, often loosely referred to as the "photon ring". I will discuss whether such features can be used as clean probes of the nature of the underlying spacetime. I will also discuss various EHT-like images of M87*, assuming this object is various kinds of compact alternatives to the standard black hole. This will allow discussing to what extent can EHT-like images help constrain the nature of the compact objects at the center of M87 or our Milky Way. |
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lundi 14 septembre 2020 - 11:00 Amphithéâtre Henri Mineur Institut d'Astrophysique de Paris |
| Pages web du séminaire / Seminar's webpage |