Dr. Becky | The first evidence for DARK MATTER in a BLACK HOLE?! @DrBecky | Uploaded 1 year ago | Updated 3 hours ago
The Event Horizon Telescope’s image of Messier 87’s supermassive black hole has given us such a precise measurement of its mass that a recent study has claimed that you can now tell that the black hole contains at least 2 billion times the mass of the Sun’s worth of dark matter. How have they managed this? And what’s the catch…? Let’s dive into it.
#blackhole #darkmatter
De Laurentis & Salucci (2022; first evidence for M87* containing dark matter) - arxiv.org/abs/2206.01997
De Blok (2009; the cusp-core problem) - arxiv.org/pdf/0910.3538.pdf
McConnell & Ma (2013; more on the black hole mass and velocity dispersion correlation) - arxiv.org/pdf/1211.2816.pdf
My previous video on all the evidence we have for dark matter: youtu.be/nbE8B7zggUg
My previous video on whether black holes can grow by accreting dark matter: youtu.be/9Qis5VDOd18
My thesis for anyone who wants a deep dive read: ora.ox.ac.uk/objects/uuid:c7023345-ec69-42c3-907e-32c12a9ee115
00:00 - Introduction: the claim that M87’s supermassive black hole contains dark matter
01:35 - A brief recap on what dark matter is
02:34 - How do we know dark matter is collisionless?
05:10 - Why black holes can’t accrete collisionless material
07:07 - Black holes are “bald” so we can’t directly test this
08:05 - The two pieces of evidence used by this new study
09:35 - CAVEAT 1: The scatter around the correlation between black hole mass and velocity dispersion
11:34 - CAVEAT 2: The cusp-core problem with dark matter distributions
12:48 - Outro
13:21 - Bloopers
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📚 My new book, "A Brief History of Black Holes", out NOW in hardback, e-book and audiobook (which I narrated myself!) Note, USA & Canada hardback out 1st November 2022: http://hyperurl.co/DrBecky
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📚 "The Year In Space" celebrating all things space in 2022 from me and t he rest of the Supermassive Podcast team: geni.us/jNcrw
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👕 My new merch, including JWST designs, are available here (with worldwide shipping!): dr-becky.teemill.com
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🎧 Royal Astronomical Society Podcast that I co-host: podfollow.com/supermassive
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🔔 Don't forget to subscribe and click the little bell icon to be notified when I post a new video!
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👩🏽💻 I'm Dr. Becky Smethurst, an astrophysicist at the University of Oxford (Christ Church). I love making videos about science with an unnatural level of enthusiasm. I like to focus on how we know things, not just what we know. And especially, the things we still don't know. If you've ever wondered about something in space and couldn't find an answer online - you can ask me! My day job is to do research into how supermassive black holes can affect the galaxies that they live in. In particular, I look at whether the energy output from the disk of material orbiting around a growing supermassive black hole can stop a galaxy from forming stars.
http://drbecky.uk.com
rebeccasmethurst.co.uk
The Event Horizon Telescope’s image of Messier 87’s supermassive black hole has given us such a precise measurement of its mass that a recent study has claimed that you can now tell that the black hole contains at least 2 billion times the mass of the Sun’s worth of dark matter. How have they managed this? And what’s the catch…? Let’s dive into it.
#blackhole #darkmatter
De Laurentis & Salucci (2022; first evidence for M87* containing dark matter) - arxiv.org/abs/2206.01997
De Blok (2009; the cusp-core problem) - arxiv.org/pdf/0910.3538.pdf
McConnell & Ma (2013; more on the black hole mass and velocity dispersion correlation) - arxiv.org/pdf/1211.2816.pdf
My previous video on all the evidence we have for dark matter: youtu.be/nbE8B7zggUg
My previous video on whether black holes can grow by accreting dark matter: youtu.be/9Qis5VDOd18
My thesis for anyone who wants a deep dive read: ora.ox.ac.uk/objects/uuid:c7023345-ec69-42c3-907e-32c12a9ee115
00:00 - Introduction: the claim that M87’s supermassive black hole contains dark matter
01:35 - A brief recap on what dark matter is
02:34 - How do we know dark matter is collisionless?
05:10 - Why black holes can’t accrete collisionless material
07:07 - Black holes are “bald” so we can’t directly test this
08:05 - The two pieces of evidence used by this new study
09:35 - CAVEAT 1: The scatter around the correlation between black hole mass and velocity dispersion
11:34 - CAVEAT 2: The cusp-core problem with dark matter distributions
12:48 - Outro
13:21 - Bloopers
---
📚 My new book, "A Brief History of Black Holes", out NOW in hardback, e-book and audiobook (which I narrated myself!) Note, USA & Canada hardback out 1st November 2022: http://hyperurl.co/DrBecky
---
📚 "The Year In Space" celebrating all things space in 2022 from me and t he rest of the Supermassive Podcast team: geni.us/jNcrw
---
👕 My new merch, including JWST designs, are available here (with worldwide shipping!): dr-becky.teemill.com
---
🎧 Royal Astronomical Society Podcast that I co-host: podfollow.com/supermassive
---
🔔 Don't forget to subscribe and click the little bell icon to be notified when I post a new video!
---
👩🏽💻 I'm Dr. Becky Smethurst, an astrophysicist at the University of Oxford (Christ Church). I love making videos about science with an unnatural level of enthusiasm. I like to focus on how we know things, not just what we know. And especially, the things we still don't know. If you've ever wondered about something in space and couldn't find an answer online - you can ask me! My day job is to do research into how supermassive black holes can affect the galaxies that they live in. In particular, I look at whether the energy output from the disk of material orbiting around a growing supermassive black hole can stop a galaxy from forming stars.
http://drbecky.uk.com
rebeccasmethurst.co.uk
