Black Hole Mergers and Multi-Messenger Astronomy - Sixty Symbols

[@AmmoBoks]

I can never get enough of prof. Copeland's enthusiasm and he does such a great job at trying to explain complex matters to the masses.

[@spazmobot]

The sign of a great teacher, is being able to explain things, to different students, in the way the student learns and understands. And he makes it exciting, bonus.

[@garrysekelli6776]

He's wrong though cause black holes and gravitational waves don't exist. Pure fantasy from heads like these .

[@staurneskristiansen8376]

@@garrysekelli6776 right on

[@spazmobot]

@@garrysekelli6776 He's guessing, it's a theory he's working with. Great teachers can open your mind to new possibilities, I never take it as fact, because they don't know enough yet. But they can inspire others to think in new directions, even prove them wrong. I like to hear all ideas and theories.

[@garrysekelli6776]

@@spazmobot well that's a complete cop out. I mean like mate: either it's real or it isn't real. So what you are saying is that cause what this guy is saying is so revolution ary that we need to revamp our entire society.

[@avinotion]

I love listening to Professor Copeland explaining these things. Always a pleasure.

[@justinoblanco]

Really wish I could find some extended lectures of his.

[@bluekeybo]

This is what science is about. The way the professor humbly accepts that his theory is out based on new data, and is not married to an idea but knows to look at things in a factual way, is what we need more of in our society today.

[@smbhquasar1527]

true!

[@AsmodeusMictian]

Well, you know, that's just the universe's opinion on the matter... ;-) /s

[@jlivewell]

This has to be one of the longest, yet simplest, explanation of the most exciting new field of Science! I mean…I could’ve listened all day!

[@limbridk]

Really enjoy listening to Copeland explain. Please tell him we want even more with him! (that does NOT mean we want less of the other wonderful professors)

[@allenyordy6700]

Professor Ed Copeland for the win my absolute favorite professor

[@scottwatrous]

I could listen to Ed talk for hours and hours. I've listened to his previous interviews on this channel many many many times now. Having a new one to listen to, and on such an exciting topic, has made my whole week better.

[@scottrobinson4611]

I went to UoN and Ed was my lecturer for a couple of modules. His voice is so soothing, it's dangerous for those early morning lectures. It was like being read the most fascinating bedtime story.

[@scottwatrous]

@@scottrobinson4611 Oh man that's luxurious and dangerous in double measure. I, not a morning person by any measure, would be utterly doomed.

[@erikfinnegan]

Prof. Copeland is my personal favourite in the line-up for sixty symbols. They're all great, the bar is high. But it's just that I feel a little bit more humbled when, through your videos, I get the opportunity to sit down with this wise and calm professor.

[@Arthur39100]

Happy to see Proffesor Copeland again!

[@fatalinsomn1a182]

This is one of my favorite channels. I love how you can break these complex things down into simple language. I have learned so much about physics from watching you and some others, and I hope I can get around to learning the kinds of maths to understand this stuff better one day.

[@duroxkilo]

17:07 the frequency signature (the particular sound) of an musical instrument can be recognized regardless of the amplitude of the signal, as long as it's at least partially above the noise floor. a violin and a trumpet playing the very same note are quite distinguishable from each other even at low SPL (different amplitudes for different harmonics). to take it farther, even just by ear, we can recognize the voice of someone familiar to us if they're whispering or talking over a poor quality phone connection. w/ a lot of data missing, a pattern/ the voice signature can still be recognized. that's how i understand analyzing the faint gravitational wave signals.. :} another great upload, thanks to everyone involved. truly enjoyable, wishing you all all the best.

[@jameshays2646]

i'm a musician and i can't believe i didnt make this comparison, thanks. though i'm a performer, not a sound engineer lol

[@andersfornberg]

So glad to see another fantastic Prof. Copeland video. He has such a great gift for explaining and expressing the wonder of these incredibly complex physical phenomenon to us amateur arm-chair particle physicist , like myself. Thanks Prof!

[@benoitb.3679]

Never knew our man Ed was a collar up kinda guy. Thanks for yet another fascinating video!

[@beezymeech]

Ed is the man bro

[@thomashenderson3901]

Collar up is the only way to rock a polo neck!

[@tb-cg6vd]

I'm so glad that after watching these Sixty Symbols uploads for years they're popping out new stuff building on old stuff - it's like watching science in action!!! Who'd have thunk it?

[@zathrasyes1287]

Sixty Symbols is one of the very best science news here on KZbin.

[@tedsword]

On the Hubble tension at 16:10: "As long as you can pinpoint how far away the object is and the polarization of the light, then actually, the expansion rate of the universe will pop out. It will come out. It will be a direct measurement." I wish Prof. Copeland could expand on that in a future video. I would love more information on how measuring the properties of these mergers can reveal the Hubble constant, and why this method is not constrained in the same way that the study of the CMB or supernovae would be.

[@ElectronFieldPulse]

I'm guessing how fast the universe is expanding will shift the light coming in, changing its wavelength. If you know the distance, you can measure the change in wavelength and determine the expansion required to result in that change.

[@tedsword]

That's one of the ways we measure the expansion rate today. We use type 1A supernovae, which always explode when they reach the same critical mass, so they can be used as a so-called "standard candle" throughout the universe because they are believed to always explode with the same luminosity (I read somewhere recently that there may be outliers in that data, but we can ignore that for now). We use that in combination with redshift to get one value for the Hubble constant. My naïve understanding of the way we would perform this measurement with gravitational waves would be to derive the original energy of the collision, then measure that against the energy received to understand distance from us. Beyond that, every popular explanation I've read has been too hand-wavy to get anything meaningful out of it. The way I interpret Prof. Copeland's words at 15:53 is that there is something intrinsic in that data that is not in the supernova data that could give a definitive answer, and that's what I'd really like to dig into. At 15:53, he says that the supernova and CMB data "rely on you understanding the cosmology of the system". And I totally get that for the CMB -- our understanding of the Hubble constant relies on our understanding on the CMB. I'm less sure why that is for supernova data, but regardless, I'd love to understand why all of the necessary data is self-contained in the gravitational wave signal.

[@dl5244]

@@tedsword there is still a chance the expansion is not uniform over time and or space. It was only 2 years ago that the accepted shape of our heliosphere changed (dramatically)!

[@tedsword]

My confusion is not about /why/ they are measuring it -- I'm sure that telescope time has been proposed with the James Webb Space Telescope, as well, to measure the Hubble constant, as well. My confusion is that Prof. Copeland seemed to indicate that there is something about the gravitational wave signal that doesn't have a dependency on "the cosmology of the system", as he put it. But I don't see how the study of cepheid variables, type 1A supernovae, and other techniques to derive the Hubble constant have a dependency, either. I don't know what makes the gravitational waves technique more special.

[@l.f.3835]

Professor Copeland is such a great guy :) Always a joy to listen to.

[@ryanaromero]

Professor Copeland is my favorite on this channel, I can listen to him for hours!

[@bobdylan6237]

I love listening to Ed talk about stuff. The twinkle in the eye when he's excited about something, it's so charming.

[@infinite1der]

I could listen to Professor Copeland for hours ...popped collar and all. ;)

[@brian554xx]

Copeland has such a calmness. It has always struck me as a lovely presence.

[@Sinnistral]

I do love it when you've been rewatching sixty symbols videos for the umpteenth times and a new one pops up 😊.

[@applechocolate4U]

Always a pleasure to see prof Copeland

[@Titan.....]

This is absolutely amazing, I love professor Copeland!!

[@benjaminmacdonald9558]

Just an extra thing to add to the theories of formation, crucially we can measure how misaligned the spins are. If you imagine the BHs have a spin vector pointing up out of its axis of rotation, and similarly for the total angular momentum of the orbit, the angle between these vectors (tilt) can be measured using the LIGO data. We generally measure quantities that are dependent on tilt, not tilt itself because it's very difficult to directly measure. Misalignment and magnitude of the spins are important characteristics of different formation channels as they are called.

[@wasp89898989]

I love prof. Copeland. Literally love the man.

[@frankschneider6156]

Tis guy is truly incredible. Wish I'd have had a single Prof like that.

[@AMRosa10]

I think that Dr. Copeland is one of my favorite academics to listen to. When I hear him explain a topic, it makes me wish I had gone into theoretical cosmology so I could have collaborated with him.

[@akaelalias4478]

I really appreciate follow up videos like this. When the first detection took place, all the talk was about how this would open up the field of gravitational astronomy. It's so interesting to see now how it is starting to contribute to the field 🙏

[@robertsimene9059]

Professor Copeland is just an amazing person!

[@EntwistleDavid]

Excellent interview and very insightful questioning. Well done.

[@sillysausage4549]

Ed is back. Will be a happy watch later.

[@kquat7899]

Sometimes I feel that the engineers and experimentalists don't receive enough credit.

[@MuitoDaora]

Theorists gather more attention because is easier to make headlines.

[@Boeserbob]

*No credit besides salary. But isn´t that in most of society?

[@maikopskoy]

I'm a simple man, I see Ed Copeland on the thumbnail, I click.

[@AsmodeusMictian]

As I've gotten older, I've noticed a really weird thing. I'm getting....jealous...of people just being born. Imagine... I was born mid-70's and in JUST MY ONE LIFETIME, we've gone from launching the Voyager probes to contemplating and working towards an actual moon base. My mind just weeps at what is going to come once I've gone. AND I'm GOING TO MISS OUT ON ALL OF IT!!! -_- Thanks for the amazing video, as always :)

[@timseguine2]

I can't pass up a video with Professor Copeland in the thumbnail.

[@prasanshasatpathy6664]

Yeah!

[@orvinal2883]

the person in the thumbnail is the biggest deciding factor of whether or not I'll be clicking on the video in question

[@Triantalex]

false.

[@RaysDad]

At 22:00 a journal editor was quoted as saying the Beatles made only "limited contributions to cosmology." I would argue that the Beatles song "Across the Universe" is a significant contribution. Words are flowing out like endless rain into a paper cup They slither wildly as they slip away across the universe Pools of sorrow, waves of joy are drifting through my opened mind Possessing and caressing me

[@Al-cynic]

Copeland's explanation of how a simple set of data points backed by complex modeling and well verified theories can produce so much information, is the stuff I love most about this type of science. Evolution (which I did) works the other way, you have a simple theory that leads to very complex data.

[@Donjone]

i could watch him talk for 10h non stop

[@surrog]

This is a fascinating video, I'm very excited to see future follow up video on this subject in the years to come!

[@andriypredmyrskyy7791]

Would love a video going over how another Hubble constant measurement pops out of these multimessenger measurements.

[@uladzislauehrlich94]

I missed Ed. Very glad to see him back.

[@McLir]

Beautiful visualization of how LIGO works!

[@jacobusstrydom7017]

Great video. Questions If you are on a planet that's let's say 2 light years away from 2 merging black holes. And say you do survive the radiation and all that, what would the gravity wave be like when it passes by?

[@LieseFury]

3:01 "the lesbians bounce off the mirrors"

[@ZMacZ]

14:24 Despite the merged event horizons, you can actually tell by the still perturbating (perturberating ?) lensing, that even though the event horizons have already become one, the orbits around each other's center is still happening for at least 6 or 7 more orbits, but after that settles, there's no more, which means that the cores have now made contact. this then allows for actually telling the size of the cores. Now if there were also other types of detection on this particular event, which would maybe show an expression or outburst of high gamma particles, or a plasma stream starting to go outward, that would have been nice too. These could then be played simultaneously, with the timing synchronized by their center motion timing. If only that video cut was a little longer., because even at the end of it there was still motion in the lensing.

[@domvasta]

Bradyons just means slow particles, I.E not travelling at C, meaning they have a real, positive mass, as opposed to tachyons, which have an imaginary mass and thus cannot travel below C. All stars are bradyon stars in that they're made of matter that is not travelling at C.

[@Eastcoast_Rds]

Ed! Glad you guys a posting again

[@WAMTAT]

absolutely phenomenal work, amazing explanation

[@PeterGaunt]

Great stuff! Is there actually any explanation for even the minuscule 1.7s second difference in arrival time of the electromagnetic and gravitational waves?

[@andreilikayutub3496]

Assuming the light was slower than the gravitational waves (because I don’t think they explicitly said so) I’d say smth like interstellar dust slowing down the X-rays. Space isn’t a perfect vacuum so it’ll slow the light down a little bit like any other medium.

[@pierreabbat6157]

When two neutron stars merge, they throw off neutronium in an excretion disk, which then decompresses and splits into heavy nuclei. Maybe it's the time it takes to form nuclei and electrons from throw-off neutronium.

[@ericeaton2386]

My understanding is that it's a difference in when they're emitted. Different phases of the mergers are producing the electromagnetic and the gravitational waves, since the gravitational waves are produced leading up to the two objects actually making contact, but the light is (presumably) produced most brightly at the actual moment of contact.

[@mastershooter64]

maybe the gravitatioal waves got slowed down due to all the matter in their path bending space-time?

[@ruigebeer]

I Need a prof Copeland in my life. I can listen hours to this man.

[@marksmod]

this is my favoritest physicks professor

[@AvenEngineer]

Does this suggest that once we develop sufficiently sensitive detectors, there will be infinitely many signals detected? I'm imagining a constant white noise of low amplitude gravitational waves, with ocasional, or maybe periodic, higher amplitude events.

[@photinodecay]

Interesting way of thinking about the relationship of strong gravity and small black holes. I read somewhere that the forces will be so weak for supermassive black holes that you won't even feel anything noticeable when you pass the event horizon.

[@ZMacZ]

14:38 If a black hole has significant spin, it's the result of a large scale merger, since that merger itself preserves some of the motion in the spin, with a high degree of certainty. If it has little, it probably never merged with something similar sized. The spin is the result of two objects similar in size and mass, that orbit each other before merger. If no such orbit happens, it means that the object it merges with simply crashed close to the center, and leaves very little spin. Basically guaranteed spin is similar sized black holes merging after orbiting around a common center outside of both black hole's event horizons.

[@ZMacZ]

Joke. Two black holes merge to create a new bigger black hole. What did they do when I tried to peek ? They closed their event horizons saying "u-p-erv."

[@willisfouts4838]

We love Ed!

[@willisfouts4838]

Mr. Ed, your ability to explain these incredibly complex ideas sets you apart. While maybe not to Feinman’s level but close!!

[@ZMacZ]

8:05 The x-rays that arrived 'late' had sleight bends to them by gravity source, except for the ones that were from the source adding a sleight bending to them increasing their path length by 510.000 over the distance of 300.000.000 LY. The greater the frequency of the detection method the less bending, unlike light, which may also have been capturable a few minutes or even hours later, dependant on the amount of bending added. It would be neat to have a full dataset on a phenomenon, ranging from gravitic to gamma, to light, to radio, etc. The more there is the less speculation and less "I wish we had .as well" 9:06 You were right expecting that the different detection methods yield different ATA's., except that the difference was really small for x-ray vs. gravitic, but did you also check for gravitic vs. light ?

[@UpstateAlgaeLaboratory]

Hubble constant: Cepheid:73.4 Background: 67.4... Grav waves:54.5 ... Cosmologiests: 😱

[@talktidy7523]

Guys, can you do something about the sound volume on future videos, please? I watch KZbin on my laptop and for softer-spoken interviewees it is sometimes hard to hear them, even at my max volume. A pity since Prof. Copeland has interesting things to convey.

[@HoyasBrasil]

Great video as always, fascinating stuff ! Video explaining the engineering behind LIGO would be amazing !

[@wallyfp]

Gosh! This is so amazing! When he explains it, he makes it look so simple.

[@krakhedd]

This is breathtakingly fascinating. Thank you for sharing this with us!

[@jamesroseii]

This dude is like the Bob Ross of physics. He always seems like a really wholesome guy.

[@trainwreck3697]

yessss haha great comparison. both people could walk you through these super complex things in simple steps, until before you know it you’ve painted a fishpond or measured spacetime distortions.

[@loge10]

Actually, if Bob Ross had lived, he would have developed enough to include space-time distortions in his paintings! I think he was already getting there...

[@brenorocha6687]

This video left me wondering: do gravitational waves get "red shifted"?

[@AdityaMehendale]

With three (or more) synchronized observatories, we would be able to triangulate the spatial origin of each event, right? This could be compared to the direction of the X-ray burst.

[@jeffk8019]

Yes. This is exactly what happened with the event in 2017 they referenced with the gamma ray burst coupled with gravitational waves. Three detectors triangulated a position and Fermi detected the gamma rays 1.7 s later.

[@AdityaMehendale]

@@jeffk8019 Ah, I see.. I thought the third one became operational only recently.

[@ZMacZ]

20:03 At LIGO they create raw data by measuring gravitional differences. This is filtered, so only the usable part remains using high powered data crunching computers. The timing difference in the both data streams gives an angle at which this overlap occurs. That means that with such an overlap you know can plot a line towards the phenomenon from Earth. The scrubbed data can then be interpreted with the variations, and now you know of large masses in motion with the vibrations showing an orbit, which correlates with the freqency of those deviations. They are orbitting, but also their mass sizes, their speed, their distance from one another. Then you let the thing play out, and from the motion you can now re-create a 3D model, which accurately shows both objects in motion, despite both's event horizons. When this data is merged with other types of detection and synchronized, you can then also tell the size of the event horizon, and by overlaying the trajectories of the objects you can also see motion through the lensing effects, that may occur just that bit longer than the sensitivity of the gravimetrics have reached their limit and thus tell you the physical dimension or at least get a close approximation of such, with greater detail than current gravimetrics allow. This all then is achieved through Multi-Messenger Astronomy which combines or cooperates in such a fashion that all possible data that can be collected also is collected, emphasis is, and also is collimated into one single data source, which subsequently tells a whole lot more than just a single data source about said phenomenon. Once the full array of data collectors (telescopes) are in play you'd ahve more than enough data to make very intricate conclusions on just about anything happening in the Universe, after watching a few events, which then harden as predictions either get proven or disproven upon repeated observation. That is explorative astrophysics at it's very finest.

[@davidmcc8727]

These presentations are superb well done

[@simpaticode]

17:07 "How can we infer so much from such a tiny signal?" Thanks for asking this question!!

[@sheldoniusRex]

I remember back in 2013-2014 when everyone was worried LIGO would see nothing at all. Phenomenal work they're doing.

[@ChrisWilson999]

What happens to the accretion disks when black holes merge? One naked black hole or an accretion disk with a portion of the source AD masses? Are a portion of the AD masses ejected and at what velocities?

[@joe_malott]

Awesome. I get graced with a fantastic sixty symbols video.

[@Kargoneth]

Such a soft-spoken gentleman.

[@elephantwalkersmith1533]

When bh’s collide, is the information in the mass loss from the coalesced bh’s encoded in the gw’s?

[@NewbFixer]

Ed is the man.

[@RalphDratman]

Isn't that (LIGO) the same setup as the old Michaelson-Morely experiment?

[@amyclea]

Thank you for what you do.

[@Dragrath1]

Hello Dr. Copeland as you mention the Hubble tension have you read the paper "A Test of the Cosmological Principle with Quasars" (Nathan J. Secrest et al 2021 ApJL 908 L51)? The paper performs a experimental test of the Kinematic dipole assumption proposed in the 1980's and the large sample size of 1.36 million distant quasars has some very serious implications for our standard cosmological assumptions effectively falsifying the validity of the kinematic dipole assumption and thus in turn falsifying the cosmological principal by showing that the CMB dipole contains a significant nonzero cosmological component of some kind. The findings have a statistical significance of 4.9 sigma deviation from the predictions of a kinematic dipole or a 1 in 2 million chance of being a statistical fluke. This might be enough to clean up the Hubble tension due to the large systematic bias that any model with the cosmological principal assumption built in. Never forget about systematic bias!

[@alubeixu]

Amazing! I always love the way he explains things. I could've listened for hours

[@tlniec]

The description of receiving a "chirp" and then correlating/comparing it to templates sounds a lot like how modern radars work, so the principle makes sense. But in this case, the signal levels involved are staggeringly minute!

[@darthlore9457]

I love how the audio of the merger sounds like a bubble popping. It seems intuitively appropriate.

[@reallydutch2]

Amature question here, have the detections at Ligo led to them being able to calculate the elasticity of spacetime itself?

[@sadra1368]

Fantastic explanation. Inspirational!

[@fh3652]

I find it impossible not to love Prof. Copeland (I'm not trying mind you).

[@Ualik123]

Does black holes have north and south poles? Does angle between axis of rotation of colliding black holes make the difference? (should I be worry about it?)

[@MrMas9]

Love Prof Copeland

[@jonnyreverb]

I know you aren't looking for them, but would an alcubierre drive leave an unusual gravitational wake that LIGO might be able to identify?

[@mmenjic]

1:20 is there detectible frequency of those mergers ? Do we detect more and more or les and less or is it a steady rate of detections ?

[@timealchemist7508]

What a wonderful man. Brilliant.

[@sduke39]

It must be a truly exciting time to be an astronomer/astro-physicist

[@ZMacZ]

Why don't they still not couple things like LIGO + radiometrics ? LIGO always gets the first results for any distant target, since gravitational waves are unhampered by anything, with shortly therefater radiometrics. Pinpoint target with LIGO, and record as much as possible, relay position to radiometrics, they can start recording before the event is perceived by radiometrics, since they take a sleight bit longer at that range. (No not through speed differential, but more by having a sleightly less direct route.) (it simply travels a tiny bit further, astronomically speaking, like 10 light minutes at ranges of 100 billion LY's.)

[@Veptis]

With interferometry or any other kind of destructive interference - where does the "destructive" energy go? Into the constructive part (does it always exist). Since energy is conserved. If gravitational waves distort spacetime, how do they effect space different to light? Isn't light in said space and time.

[@nmarbletoe8210]

The destructive interference prevents the energy transfer before it can occur.

[@LambBib]

I wonder if all the templates are just for 2 body collisions? Is it possible to detect, for example, a 3 body collision?

[@tonycmac]

Great questions and answers! Thank you.

[@monkeymind4912]

Great answers and great questions, as always.

[@michaelevans4207]

I love all of the channels that Brady and the team create. How far in advance of a merger does LIGO detect the merger? Is this a detection only within the last few seconds prior to merger?

[@hughoxford8735]

So then. Does this mean that gravitation waves can be focused?

[@butchcoolidge2445]

I'm waiting patiently for the video about Bradyons.

[@chilledgamezone4950]

He has one of the best unintentional asmr voices

[@taba1950]

Not related to the video, I love the new channel icon

[@brihend]

I have so many questions. Is LIGO detecting fluctuations in space-time or some other field? Isn't LIGO part of the space-time it is trying to detect fluctuations in? What I mean is, wouldn't the detector itself expand and contract with the wave? If LIGO is detecting small fluctuations in space-time, is there a "Doppler effect"? I mean if space-time is stretching out as the gravity waves travel across it, would this change the frequency of the wave? If the universe is not expanding, but static, and not infinite I assume we would see gravitational waves that reached the boundary and have bounced off and come back. If we do not see this interference from returning gravity waves, would this indicate the universe is infinite, or just that the waves cannot outpace the expansion of the universe? I am sorry if I am asking silly questions. I am not educated in these matters and am trying to understand them from a KZbin education background, lol.