What a great time in human history to be alive. Sometimes it's not the answers a generation comes up with, but the questions they ask that matter. Keep up the good work and don't fret the sound issues.

Wearing a Muse shirt while talking about supermassive black holes. Subtle.

I’m so glad YT suggested one of your videos. You are instantly one of my favorite physics channels. Your presentation style is so natural and clear and balanced. It’s the right amount of simplification such that I can (mostly) understand the subject matter with enough scientific information that I actually learn something. Fantastic job.

I come for the science, but remain for the outtakes! Thanks for the knowledge!

Even as a layman, I'm so intrigued by this channel and everything you cover. I may not understand it all on your level but it's still fascinating. I could watch this stuff all day.

You are so good at explaining this information.. Love your channel!

As a physical chemist, "collisionless" matter sounds a lot like frictionless matter, such as a superfluid like liquid helium-4.

I'm an aspiring astrophysicist and plan on someday getting my degree in astrophysics, and i spend all my free time watching these videos because they are so informative! Thanks for providing such great information!!!

So, the "Betteridge's law of headlines" also applies to peer-reviewed papers :D

Once i saw the title i just realized "Why'd i never think about that before". Thanks for making this video, was not the conclusion my gut reaction expected. I expected the majority of matter to compose the majority of matter that goes into black holes. But your explanation made it very clear why we shouldn't expect that to be the case. I hadn't known dark matter was collisionless, but that makes sense. If dark matter is made of multiple different types of particles is it possible some of them are collisional but just not what composes the majority?

Ive literally wondered this! Thanks Dr. Becky!

I've been wondering this question for 10 years and it's the 1st time I see an video about it.

Yes partical physicists, hurry up why don't ya! Nice shirt too.

Awesome job on the lighting and white balance! Also MUSE FTW!

The answer to a question in a title/headline being no is called Betteridges law. It's intuitive when you think about it, neutrinos are also weakly interacting, don't form accretion disks, and likely have the same low probability of passing within the schwarzschild radius.

Sound quality aside, this is one of the best videos of yours that I've seen! Thank you.

Look up DIY Sound Deadening panels for a cheap way to improve your audio 😁

Muse shirt wins the internet today.

Just found your channel; this video impressed me so much I instantly subscribed. I love how you make the tough stuff, the questions being asked in these papers, readily available and easily understood by those of us not in the loop! Looking forward to checking out more videos!

Thank you for taking something confusing and making it a little less confusing.

Just found your channel. Great question, great video, great explanation. Had to pause it to think through what you had just said at some points. {Me}

Then black holes usually friendzone dark matter with very low chance of collision ;)

Dark matter has always been one of those things that up until this point felt to me personally less like astronomy and more like (shudder...) astrology. But listening to your attempts to sort out and understand how something as yet still poorly understood as dark matter into a very practical and very real explanation as to how it would interact and behave in a much more understood and observed setting are absolutely fascinating for one. And more importantly for myself, allowed me to more firmly grasp the concept of dark matter as something actually real and observable, at least theoretically and to a limited point. But far more real for me than when I started watching this video. Well done! Thank you!

Besides the answer "we don't really know" it seems the current papers are saying that we don't expect significant amounts of dark matter to be captured by black holes. The reason I hear in this video is that dark matter doesn't strongly interact with itself or with normal baryonic matter through the electromagnetic force. This weakly interactive behavior stops it from clumping like normal baryonic matter so it doesn't lose energy and fall into black holes, or stars, or planets. This is quite non-intuitive but if there is no electromagnetic interaction (friction) to slow things down, a piece of dark matter would travel right through a star or planet as if it weren't there. Gravity would speed up as it approached the center of mass and slow it down as it passed by until it was back to the initial speed it had before the interaction. Unless it were on a collision course with the event horizon (where it would be stuck in the black hole), it would follow a parabolic path around a black hole and continue on its merry way. This is why so little dark matter is captured in the black hole. Thank you so much for explaining this.

Supermassive Black Hole Hysteria is the best hysteria, Muse-puns intended.

Isn't the answer to all dark matter questions currently, "we don't know"?😂 great video! Thanks for keeping us all up to date on the status quo :)

Love Dr. Becky's bloopers, nice touch...

It makes very little difference, but for some reason i find it really pleasant to hear a british voice explaining science for a change. I seem to follow all the american science channels. Subscribed, and totally not biased.

Since we infer the existence of Dark matter by its gravitational interaction with normal matter, that would seem to imply that it would still feel the gravitational attraction of a black hole. Further if it can't loose it angular momentum via collisions and thus can't fall into a black hole, then would Dark matter pile up around a black holes due to being attracted gravitationally and but being unable to fall in?

What would happen if anti matter fell into a black hole? Would it add to the mass or remove mass?

Thank you Dr becky. So smart and intelligent and yet you seem so friendly and approachable. People we might have found the perfect science educator!

I asked a question along these lines several years ago, and the only one time I got an answer was by someone that totally misunderstood what I was asking. I have emailed physicists and commented on youtube videos, and no one ever came up with an answer, and as I don't know the physics really, I don't even know if I am just failing to understand. I titled my question "Stable Pulsar's disprove WIMP model of dark matter" Points: 1. WIMP's would travel far below the speed of light to be able to stay roughly connected through gravitational attraction to galaxies, anything traveling at the speed of light would not stay bound to anything other then inside a black hole, so there could be no dark matter halo. 2. We don't see neutron stars and or pulsar's that appear to gain mass and eventually collapse into a black hole on their own. 3. There are many paths for any given object in the presence of a strong enough gravitational field, and not traveling at the speed of light, a set of paths that will leed to capture of that object into orbit of the the strong gravitational field. 4. A portion of dark matter WIMP's that cross paths with a neutron star, even if they manage to not interact with the basically solid matter ball that it is, could end up in orbits, likely below the surface, of the neutron star. 5. No matter how non-interacting they are, they should over time build up in mass inside the star, eventually pushing it past the mass limit for a black hole. 6. And or conversely, they do interact enough, that the stars should gain heat and only ever get hotter and brighter the longer the exist, due to the interactions with the WIMP's

Dr. Becky, does the recent picture of the M87 black hole put some light into this question?

Doesn't dark matter orbiting black hole lose energy via gravitational radiation or is this so slow process that it does not matter? If so, this does bring up interesting question. Which one happens faster: black hole evaporation via Hawking radiation or dark matter absorption due gravitational radiation?

I've actually thought of black holes growing from dark matter too, but i figure the professional scientists would have thought of that already. Does dark matter not collide with itself in a hypothetical dark matter accretion disk? For that matter, would there be dark matter "stars?" Just balls of dark matter that doesn't glow, but has an unexplained planetary system or system of gas and dust around it? Hard to detect for sure since its not something you could see in a telescope until it birthed a star of its own.

You are my favorite channel right now.

Dr. Becky your hair looks extra fabulous today. 😍

As Stars orbit galaxies, why don't they accumulate dark matter along their orbital path, when the speed is about the same as the dark matter?

Speaking of dark matter, a good friend of mine is a physicist and he told me about the theory of quantized inertia, which, among other things, says we don't need dark matter to explain our observations. It's a pretty interesting idea, and I know it's just a fringe theory, but I'd like to hear your take on it if you think you could make a good video on the topic.

Love the quirky bits at the end and of course the video..always extremely informative

I barely understand a tenth of what you are saying, but I love the enthusiasm. What is your take on quantized inertia? (no dark matter at all, just a Hubble scale casimir effect)

Muse, Super massive black holes

Improved audio would have made this video much more enjoyable. I almost clicked off in the first 5 seconds based on poor audio alone. My curiosity of the title kept me here, but I assume most missed this interesting video. All other quality metrics are great! Subject, Editing, Camera. I look forward to the success of this channel and enjoying more content. ;) Edit: I just watched the last few seconds that you say your mic battery died.

Hi Dr. Becky. If you are up for some questions: (1) Does dark matter pull on other dark matter? (Or it only attracts matter? This might affect every simulation...) (2) What is the temperature at the center of a black hole? (Infinite? Or... zero... because nothing can move???) (3) Do we know the crushed diameter of everything subatomic particle - including photons? (Why can't we assume zero space in between and calculate the core diameter of a black hole from its known mass, based on the diameter of the calculated number of all of the subatomic particles it contains - making some assumptions course?) (4) Why does everyone believe a black hole can exit via a white hole through other dimensions? (If the mass of a black hole is known then it's all trapped in there - right? Being squished to somewhere else would reduce the measurable mass - right? (5) Can a "black hole made up entirely of photons really exist? (If not then why can't you "evaporate" a black hole made up of matter by throwing an equal amount of antimatter into it? (Yes - initially the photons would be trapped. But after enough matter - antimatter masses are all converted to photons, then the black hole no longer has sufficient mass to sustain a sufficiently strong gravitational field to hold itself together.) -- Thanks, and great work!!

Black holes contain donuts. Prove me wrong.

Imagine, maybe there is no such thing as "dark matter".

Never mind. I should wait til the video finishes!

Loved the video! Clear and to the point but without forgetting to quickly explain other stuff like gravitational lensing. And you're good to listen to as well.

Yup, "Dark Matter" sure is versatile. But that's how it is, when you make stuff up. Then it fits however you want.

Dark matter is made up of the souls of undead bunnies

Damn, you got me thinking now. Colisionless matter... that only interacts through gravity. A whole new research venue, just like discovering where exactly the mass property lies. Astonishing, keep up the good work!

Subscribed today. Weird KZfaq hasn't recommended these videos to me before.

Maybe dark matter and energy is/are other dimensions. We can't interact , but all that stuff is still there even though, it's not... What needs to happen, is a visit from Uncle Martin. To explain how to simply manipulate space time. it may just be a branch of physics that is yet to sprout. We can't seem to de linear ourselves or separate perception from thought. There are ways But it's a family show....

Great content, bad audio

Two questions: 1) Does this mean that black hole get larger and larger amounts of dark matter orbiting them over time? If not, why not? Wouldn't dark matter that came into the black hole's area of influence keep drifting in? Also what about dark matter that _did_ happen to come straight in dead center? 2) Do we have tests and data yet to say for sure that black matter exists versus there's some basic misunderstanding of the laws of physics? i.e. is it settled science now that there is black matter vs it just looks very likely?

When a black hole forms, and it's event horizon snaps into place, will there be dark matter that "falls" into the black hole since that dark matter is already within the event horizon? (ie, that dark matter will have contributed its "mass" to the mass of the singularity? Also, If dark matter affects gravitational forces, can dark matter itself be affected by gravitational forces? Would it need to be an exceptionally strong gravitational source (black hole, stellar core, entire galaxy) to have an observable effect? (would it clump and thereby generate a stronger gravitational force?)

Damn your lovely eyes, i come here for the science, and have to watch twice because I haven't listened properly. Thanks for the vids, Becky

It's like asking do unicorns fart rainbows? ALL of it is mathematical nonsense and entirely fictional.

Alot of physicists rather attribute 'Dark Matter' as Dark Gravity as far as I know. Since the only current way for us to oberve this phenomenon, is due to its gravity properties and the way Galaxies cluster. That being said, since Black holes have infinite density is it not possible that 'Dark Matter' increasing a size of the black Hole and only measurable by its gravitational pull, not so much matter being sucked in, but the gravitational properties of the 'Dark Gravity' being added to the black hole? Since the way we describe how 'heavy' a black hole is due to its equivalent gravity properties to mass, even though the Black holes gravity attraction is proportional to its radius, we cant say how heavy it actually is? Im an engineer, not a physicist, so I might be completely missing the ball here though.

this channel is awesome and should be larger.

Dr Becky marry me, I love you brain :) lol

Dr. Becky. I have two questions: One reasonable and one wild, and I'd be flattered if you'd humor me by answering both. 1. Why isn't dark matter just referred to as "unexplained space-time curvature"?, and 2. Has anyone considered dark matter as being curvature caused by a large mass from *outside* our universe--i.e. a nearby parallel universe, and we assume gravitational waves can permeate beyond our four known dimensions and towards other parallel universes?

It was spectacular watching CHANDRA go up on Columbia. Such an underappreciated observatory.

First time tuning in. Great job in explaining the proposition of dark matter vis-a-vis black holes. Enjoyed it.

This is the first video that I've found on this channel, but I already know this Dr. Becky is a great place to go for physics. The information is simple yet profound, the script is very natural, which makes me think that you know a lot about the subject you're explaining. Also, the ideas for the videos I've seen so far seem to be varied, thought-provoking and original. One thing: invest in a camera. I know you've probably got this often, but if you do invest in a camera, you'll be all set! I know that it will cost a lot, but I find that upgrading your kit will be a big step forward for this channel. I see a stellar future for this channel, good luck!!

I like that you do a great job explaining complex topics in a way that is very easily follow. Also cool how you bring in studies by others. Interesting how your videos teach about the topic but also about the study behind the topics. Of course the outtakes are great as well 😄 Nice work! Subscribed!

Thanks for adding the bloopers at the end, makes me feel better about taxing my brain to follow someone far cleverer than I. 👍

OK, we need a Dr. Becky blooper reel-dedicated video, stat!

I think the last few sentences sum up most of my astrophysics experience: "maybe/we don't know" lol I did my bachelor's thesis on the question if baryonic feedback can be sufficient to form cored dark matter density profiles in faint galaxies and you can guess the results

What I think is much more interesting is that if a black hole can be at least partially made up of dark matter, then in theory it should be converted to energy via Hawking radiation. So in theory you could map out where the bigger clumps of dark matter are, carry along a portable black hole (assume that's possible for the moment), and convert it to energy via Hawking radiation. So in theory we have more energy than previously thought. This should also mean that once a black hole explodes it should convert not just regular matter but also all of the dark matter into energy (unless I'm mistaken which is distinctly possible.)

Very easy to understand explanation. Dark matter has to lose energy in order to be drawn in past the event horizon. I wonder though if there are quantum effects, such as virtual "particles" to where one virtual dark matter "particle" would be drawn into the hole while its entangled twin did not. Yes particle physicists hurry up why don't ya! I am now a new subscriber Dr. Becky. Thank you!!

Really enjoy the presentations of this channel. Dr. Becky makes it understandable for us all.

I arrived here almost directly from Straya's Bin Chicken video.. Good show, Dr Bec.

Just a general comment, Dr. Becky...I really appreciate your videos, you explain things so well and it's exactly in the range of understanding that I look for in these subjects. Your qualitative and visual approach to describing cosmic phenomena is very clear. Keep up the awesome work. I also love the outtakes!

You're doing great videos and keeping me scientifically curious. Thanks, fun to watch!

Just found your channel. I'm a huge fan of "what the math" with Antone and your channel is a great compliment to his content. Love your style

I love your content, please never stop.

Dr Becky please have a part of your podcast when you answer questions. Unlike dark matter orbits of reflective matter experience drag and that would cause their orbits to decay and end up in black holes. However dark matter does get pushed away by matter either. Once any massive object comes into contact with dark matter it will hold on it and if the object falls into a black hold so will the dark matter.

Have been learning about superconductivity this week, and how you describe dark matter as collisionless reminds me of quantum fluid. There appears to be a new theory that the surface of black holes are actually surrounded by a superconducting plasma, and if the mechanism of accretion is collision then that would mean that the frictionless quantum fluid is never accreted. Feels like the pieces of the puzzle are only waiting to fall in place.

Thank you for this wonderful explanation! I once had a very cool discussion about a very similar topic with a group of folks much more educated on Physics than me at a Science Getaway (with Dr. Phil Plait). While several folks there were physics PhDs, none were as tuned into this as you, so we were all just kinda speculating about the dark matter halo and whether it would ever get captured by black holes or other dense gravitational areas (stars, etc). We *guessed* that the lack of friction would mean the DM wouldn't slow down enough to get sucked in, so you might wind up with a slowly growing mass of orbiting DM. It was a wonderful midnight discussion with finger-drawings of potential DM orbits in all three dimensions on the table... I am super glad to know that we were at least in the realm of plausibility with you folks who actually know this stuff. I can't wait to hear more as we learn more.

Has any progress been made about what dark matter isn't? It's an odd question, but since we don't what dark matter is, have any promising theories been ruled out?

Even Dr. Becky's flubs at the end sound smarter than me on a good day. Can't wait till you good scientists figure out what this weird dark matter is!

Hey, just wanted to tell you you're great, have a great way of explaining things followed by awesome animations unlike most space related channels out there who mostly borrow already overused animations from old documentaries :) Good luck!

very clear :) on black holes

I've never subbed faster. I love Becky.

We always come because of the outtakes =)

Hi. Wow. What does it feel like to think so deeply? I mean "normal" people don't really think about this stuff, right? But I find this stuff fascinating. Thank you for sharing your finds. 👏👏👏🇿🇦🇿🇦

That "collisional/collisionless" outtake made me smile.

Good to see the ventriloquism lessons are paying off at the end there....

2 things. 1st, dark matter is collisionless with its self but not with normal matter. That means, if the accretion disk is full of normal matter it should be able to collide with any dark matter that may also be in the disk. More so the closer to the inner disk it is. This brings me to my 2nd point. If normal matter can collide with dark matter wouldn't the most likely place to see that happen be in the accretion disk of a black hole? If so, we should be able to detect it, measure it and learn more about it. Hopefully we will have the ability to do this soon. We just took a huge step by imaging a black hole.. well, its shadow anyway... and I think that should make us hopeful for what's soon to come in science.

Great video, I love the out-takes at the end too...also your hair and your eyes and...

Last Friday at the Delaware Valley Astro Club, we heard a timely talk by Dr. Joseph Neilsen, Villanova University on Black Holes. Dr. Joe has degrees from Harvard & MIT, so he is top knotch. Our club meets close to the University who has added outstanding talent to its physics department. I shared your YT video with him. He's very young like you and demonstrates lots of enthusiasm also like Dr. Becky! 🤗

Do you think it's possible that dark matter might just be a mathematical error in our idea about how galaxies should spin? At least that portion of it (the so called "impossible" galaxies) And what do you think about halton arp? After he died the astronomy community kind of just swept him under the rug... his catalogue of weird stuff still hasn't really been addressed

So glad you covered this topic. I had been thinking about this question a bit over the last few months, especially relating to supermassive black hole formation in the early universe. Whatever dark matter actually is, when it was first formed with the rest of the universe, and was incredibly dense, would it be possible that the densest areas of dark matter could have created supermassive black holes under their own gravity, while normal matter was being prevented by collapsing due to the intense heat it was subjected to?

Dr Becky, You are a True Super Heroine! Thanks, Mike from Wyoming.

I feel your pain re: motorbikes. Used to have a Harley-Davidson owner just down the street who always seemed to know just when I was recording!

You're inspirational, also, awesome shirt.

Haha, love the outtakes.

Feedback for Dr in the house. I have watched plenty of your videos and I really enjoyed this one. It was definitely worth making. Great job.

It's becoming more and more solidified in my opinion with everything that I hear about Dark Matter and Energy. It seems to be a cognitive representation of four Dimensional time, as a object. Time shapes all objects. But some objects are just time, like space for example.