Gravitational Waves Discovery - Sixty Symbols

Discussed by Ed Copeland and Mike Merrifield.
Extra footage from these interviews: • Gravitational Waves (e...
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[@ImprovedTruth]

A fantastic C3PO impression: 5:48

[@SamuelHauptmannvanDam]

Made my day! Brilliant!

[@Triantalex]

??

[@Wardropulous]

These two professors are probably my favourites to listen to of all Brady's channels. Their knowledge, how they explain things and how they talk all make for a great listening experience.

[@123456sickofcounting]

I love the passion these men have for science. You can fake a smile, even intellect. But a passion of that level is nearly beyond finite to replicate.

[@CastelDawn]

nicely said.

[@lucasthompson1650]

Search for "duchenne markers" … now nobody can fake a smile around you.

[@YuTe3712]

Every time I see those two graphs aligned so well with each other, I feel shivers down my spine at just. how. awesome. it is that we could detect ripples in space-time. Ripples in space-time. Ripples in the true fabric of the universe. How. Awesome. Is. That.

[@chadcastagana9181]

Did you ever get out of the basement after watch Star Trek :-)

[@DreckbobBratpfanne]

But a sad note in this regard is, that because the NASA budget is so low, we don't have waaaay better detectors within satellites. There were two big plans, both got postponed decades :-/. LIGO has 4km arms, these satellites would've had 3 million km ones. These are so sensitive we could detect stuff we might not even know about.

[@Triantalex]

..

[@IMadeOfClay]

I'm surprised neither Ed nor Mike detected the gravitational wave that ripped past the screen at 3:00.

[@XxxclarityxxX]

+MadeOf Clay xD

[@freebiehughes9615]

😂😂😁

[@Triantalex]

??

[@SaraBearRawr0312]

Despite this being a very complex topic, this was probably one of the best explained videos from sixty symbols.

[@bonbonpony]

+TJW595 If this was "best explained", then I don't wanna see their other videos :p

[@SaraBearRawr0312]

+Bon Bon you ought to try their video on the higgs

[@bonbonpony]

TJW595 I'm not sure my nerves can bear that. They're already devastated by "scientific" programs on Discovery Channel :/

[@AlkisGD]

The sheer _enormity_ of it all is mind boggling. ~30 solar mass objects moving at 60% light speed, emitting 3 solar masses worth of energy faster than a human can blink. Wow.

[@RemizZ]

I just love how genuinely excited they are about this :)

[@cordx5068]

+RemizZ No wonder - all the stuff is almost beyond comprehension:) I am excited myslef even though I am a scientific moron compared to the Sixty Symbols guys :)

[@MatthiasVargas]

I'm glad my home state of Louisiana was in the news for something that I'm not ashamed of

[@CatnamedMittens]

+MatthiasVargas Louisiana is great.

[@CatnamedMittens]

***** Lots of culture and historically significant. Nice people too.

[@darealtuck4420]

tide goes in tide goes out, you can't explain that

[@philipchristiansen1495]

+Invalid Pleb hahahahaa

[@erictaylor5462]

+Invalid Pleb Dr. Tyson to ER Stat. Dr. Tyson to ER stat.

[@aussiepassenger]

+Invalid Pleb Haha mate, exactly my thought when that bit came XD

[@whopperlover1772]

Huh?

[@911gpd]

where does this come from ? please ;)

[@Twitchi]

Always love to see a bit of Ed, something about his style that really appeals to me :D

[@Pow3llMorgan]

+Twitchi It's the sign of a good teacher. A very good one :)

[@squimped]

Indeed! He seems so incredibly friendly and is almost always smiling. He's the kind of guy I could sit and listen to forever.

[@joelproko]

Ed seems to be an extremely sympatical guy. Love that smile of his.

[@BlackBobby69]

Always a pleasure seeing you go back to the classic style of Sixty Symbols video with two professionals independently explaining the topic.

[@H0A0B123]

That man is *Happy*.

[@EugeneKhutoryansky]

Looking forward to the day when we have many more gravitational wave detectors, each of which is far more accurate than the two we have now.

[@vegarsc]

+Physics Videos by Eugene Khutoryansky I guess the next step is building these detectors in space, just as optical telescopes have been placed in space to get rid of noise. Edit: Also looking forward to your awesome animations to further illustrate this phenomenon.

[@ShaneClough]

I'm not sure that these detectors would work in space. I have a feeling that there would be some kind of relativistic effects messing up the laser calibration due to the fact that they would be in orbit. I could be wrong though.

[@GumbootMan]

+Shane Clough (BRUTALBREAKD0WN) Relativistic effects are minor at orbital speeds, and can easily be corrected for due to the extremely predictable motion of objects in space. In fact the EU is already planning to launch a space-based version of LIGO, which is called eLISA, with a tentative launch date set for 2034.

[@ShaneClough]

Paul Bartrum Yeah, after I commented that I realised that it probably wasn't correct. I mean, they do relativistic corrections for GPS satellites as is. Either way, thanks for the clarification.

[@Ducksauce33]

Looking forward to the day when you have even more weird owls in your videos then you have now.

[@TheLuxma]

Ed is just adorable

[@chadcastagana9181]

If you like dweebs

[@billyhendrix5544]

Who's ed

[@hughoxford8735]

Don’t be fooled. In his spare time he’s a notorious gang land enforcer with a hair trigger temper.

[@PhysicsPolice]

7:00 This absolutely blows my mind.

[@greenanubis]

+PhysicsPolice And most of it was generated in fifth of a second!

[@PhysicsPolice]

I know, right? That luminosity, though...

[@SunajVon]

Thank you everyone who participated in this video, for the time and work put into it, and thank you for SHARING this with us :)

[@michaelsheffield6852]

The Joy of the descriptions is beautiful.

[@j7ndominica051]

It blows my mind that they could detect oscillations with amplitude less than a nucleus. Amazing engineering.

[@David_Last_Name]

+j7ndominica0 It is, but consider that once we get some space based LIGO detectors going, the sensitivity will go up by orders of magnitude. Since the sensitivity is based on the size of the LIGO arms (today it's at 2.5 miles), and space is already a vacuum, you can place 2 satellites as far apart as you wanted to and just bounce a laser between them. 10,000 miles? 1 million miles? 1 billion? All technically possible. It will be like going from Galileo's first telescope to the Hubble. lol.

[@kalidesu]

+David Stagg Space isn't empty. I believe even Einstein talked about the aether in the 1920's, the QT clown's call it Quantum fluid.

[@David_Last_Name]

kalidesu Space is not 100% empty, correct. But neither are the vacuums we can create here on Earth. In fact compared to the best vacuums we can create, space is actually EMPTIER then our vacuums. So for the purposes of a LIGO detector, space works better then the vacuum tubes we are currently using. But Einstein actually disproved the aether concept. He certainly didn't promote it, and CERTAINLY not in the 1920's when relativity was already firmly established. I'm not really sure what you are bringing up there.

[@kalidesu]

"Einstein actually disproved the aether concept" Not really it was just inconvenient to his relativity theory. Einstein borrowed a lot concepts from other scientist at the time, so his work was on the back of giants.

[@David_Last_Name]

kalidesu Not just inconvenient, Einsteins theory completely did away with the aether concept. His theory satisfied the propogation of light paradox without needing the aether at all, rendering the concept pointless. Because it became pointless and redundant, the notion of the aether stopped there.

[@anon6514]

3 solar masses in a fifth of a second? 3 x (2x10^30 kg) x 5 x (3x10^8 m/s)^2 = 2.7x10^48 Watts. wow. intense.

[@Petr75661]

+Anon yeah, about the sound output of the Disaster Area, a plutonium rock band from the Gagrakacka Mind Zones (generally held to be the loudest rock band in the Galaxy)

[@danmcann94]

+Anon spectacular and at the same time kinda hard to believe. my question is: if you would have watched the event from a close distance, would you have had felt and seen the squeezing and stretching of space time? for such a gigantic amount of energy the implications close to the black holes must have been enormous

[@Kavetrol]

+Dan M You are made of space-time. It would rip you apart.

[@fruitduck604]

wrong. the unit is joules. watt has an extra s^-1 in its base units.

[@chadcastagana9181]

How many FOEs is that?

[@SSmitar]

The way both of them corrected "Super-Massive Black hole" to "Fairly Massive Black-hole" was quite intriguing. I think, which goes to show that if you are a Physicist, you just can't throw words around even if they are esoteric.

[@KeyMan137]

+Smit Ramteke They're not esoteric. There are different classifications of black holes based on their mass, angular momentum, and charge: Class Mass Size Supermassive black hole ~105-1010 MSun ~0.001-400 AU Intermediate-mass black hole ~103 MSun ~103 km ≈ REarth Stellar black hole ~10 MSun ~30 km Micro black hole up to ~MMoon up to ~0.1 mm

[@GodWorksOut]

This is all so exciting and the way they speak about it enthusiastically makes it so much better! ^_^

[@rumfordc]

+GodWorksOut how is it exciting? this result was already predicted as they mentioned

[@rumfordc]

***** meh, i feel you get diminishing returns after the prediction itself. einstein discovering relativity is more exciting than other people discovering he was right, after all millions of kids are fascinated by relativity in school without any means to experiment with it. Clearly the excitement is in the revelation rather than its visibility

[@garethdean6382]

+Rumford Chimpenstein Because there's always the possibility of failure. Always the possibility that there's nothing there. That this neat theory you believe in, that's been so right, so long, finally hits a stumbling block. That all your effort, expense, time, calculation and hope were in vain. But when you can stand there, with that result and say 'We did this, we small lumps of meat held up by chalk sticks built a machine to peer into the most powerful yet least visible events in the universe and succeeded!' that is truly a moment to be treasured.

[@ashwith]

We now need a video of Prof Copeland going to LIGO so that we can see his LHC reaction again :)

[@markskilbeck]

I took one of Ed's modules earlier and in the year, and I would just like to say that he is even more adorable in person.

[@tcunero]

This is why I love science. So many people, working together on something so complex, it was only possible from the efforts of previous individuals, all to better understand the universe. Their work will pave the road to the future. Thank you!

[@ReneMalingre]

I love these two. Very different personalities, very complementary. Excellent editing to get the two interviews merged into one explanation.

[@Dolkarr]

I've heard that as light waves get weaker and weaker with distance, at some point it starts to look like the source of light is flashing as individual photons hit the detector one by one. Does the fact that we're not observing this with gravitational waves mean that there is no "gravity carrying" particle, or just that the ones we detected were still too strong to behave like particles?

[@GumbootMan]

+Dolkarr The latter. Individual gravitons, if they exist, are so weak that some physicists believe that we will never be able to detect them directly. As an example of just how hard it would be, if you were to scale up the LIGO experiment so that they were sensitive enough to detect individual gravitons, the mirrors would be so massive that they would immediately collapse into black holes. (And this is assuming the mirrors are constructed as physically perfect as the quantum uncertainty principle allows.)

[@lukasmorkunas9356]

I love sixty symbols, I wait, check every other day to see if there is a new upload. :) Such a great channel.

[@gauravcheema]

I have thought of gravitational waves countless number of times and have seen countless number of videos. Yet every next time i think about it, i never fail to get chills. Every damn time.

[@ZimoNitrome]

Gravitational Waves are dank af

[@insu_na]

+ZimoNitrome Imagine if gravitational waves could constructively interfere.

[@TheExoticDarkness]

+d3rrial Best dubstep ever

[@Algebrodadio]

+d3rrial They can.

[@insu_na]

Aaron Wolbach Can gravitational waves be created by humans (obviously not at black hole scale) or are even the weakest of gravitational waves impossible to create artificially with our current technology?

[@wingracer1614]

+d3rrial Move. You just created a gravitational wave.

[@steve1978ger]

Awesome, been waiting for this. Thank you very much!

[@juanchetumare]

I love how their personalities are kind of opposed but their minds so similar.

[@jacquieo9960]

how lovely is Ed Copeland

[@MarxistKnight]

The experiments that detected the gravitational waves make me proud to be human.

[@nonyadamnbusiness9887]

I'm glad the question of false positives was addressed. My first thought was how could it work with thermal expansion, tides, and tremors constantly upsetting the detector.

[@musa4539]

i love this channel

[@crsm42]

Congrats Brady, Ed and Mike. Another fascinating, engaging Sixty Symbols. at 7:14 Mike explains that 3 solar masses of energy are converted to gravitational wave in a fraction of a second; more power output than all the stars in the observable universe. Wow! Astrophysics is awesome! Thanks guys.

[@accadia50]

"This huge amount of energy required this desperately accurate detector in order to be able to find the gravitational waves." 9:30 Hearing Dr. Copeland laugh at how incredible the science is makes my heart sing.

[@MrDrewbies]

I will always appreciate all of Brady's channels, this was fascinating.

[@azyfloof]

It takes me ages to do any housework, because every now and then I'll stop what I'm doing, and just think about how amazing everything is :O

[@GeirGunnarss]

+Azayles Agreed, that is also why i cringe when i hear a religious person say that science has removed the wonder and beauty of nature. They forget that they only get to experience the wonder and awe of the surface features while we get to stand in awe at everything from the quantum to the macro.

[@azyfloof]

GeirGunnarss Oh I know! While they can only look at "Creation" on the surface, we can look much deeper and see a nearly _infite_ tapestry of beauty and wonder. There is always something more amazing, more incredible and more utterly mind blowing to learn, and so far we're only scratching the surface! The religious get their teachings from an unchanging unyielding book from 2000 plus years ago, whereas we have the majesty of the _entire universe_.

[@sergheiadrian]

Thank you Brady and thanks the professors for this video.

[@ColdCutz]

I got to visit the LIGO in Livingston last November, and they mentioned that earthquakes can actually knock the mirrors out of calibration.

[@JimFortune]

So the source of the detected gravity waves was long ago in a galaxy far away?

[@somebody566]

so this could have been the deathstar exploding!?

[@wthilmi]

U watched too much Star Wars

[@JimFortune]

Juan Fredic Carlos I've actually only seen 4 episodes.

[@hasnaosama7185]

Je ygg+François Girard

[@CastelDawn]

+Jim Fortune only 3 are worth watching anyway

[@aetherseraph]

I've watched every video on this topic, and this is hands down the best one. great job Brady...

[@cassandra5322]

Speechless, this is like a dream come true.

[@SamuelHauptmannvanDam]

This is amazing. It's insane how amazing it is. The effort and man power it takes for these detections to be made. Crazy.

[@TheTUDOR91]

According to the schwartzchild radius formula, the 36 solar mass black hole had a radius of 107km and the 29 solar mass black hole had a radius of 87km.

[@Ti133700N]

5:03 Didn't know the movie _Frozen_ was about two black holes merging together. Now I understand the lyrics: _Let it go, let it go!_

[@CybranM]

This is one of my favourite sixty symbols videos so far, very interesting topic and very well explained

[@kpbuzz]

3 solar masses worth gravitational waves!!!!!!!!!!!!! *MINDBLOWN*

[@Kavetrol]

+Krishna Prasad Hiroshima was destroyed by less than 1 gram. Lets compare it to mass of the Sun times 3.

[@kpbuzz]

Kavetrol PRECISELY!!!!!!

[@123456sickofcounting]

that is mindblowing. Literally.

[@maxgrass8134]

Mindblowing yes, but expanding in 3D for Billion Years - and the energy required to still be measured here on earth - you can imagine that a huge initial energy was required!!!

[@Alexagrigorieff]

The graphics are incorrect. The waves are drawn with pretty short wavelength, but it cannot be shorter than the orbit's half-circumference. More than that, the wavelength near to the system is a bit shorter, than the wavelength farther away, because of time dilation. The rotation period we observe in a few last moments is longer than a local observer would see.

[@dAvrilthebear]

You've told lots of amasing details about these event: for example how the black holes came together, orbiting at 60% of c and releasing tgis much energy, etc. Thank you so much!

[@innertubez]

That space between the black holes must have been hellish. Imagine being able to see from a safe distance the two black holes orbiting each other at 0.6 c.

[@sitearm]

really nicely produced, Brady ty!

[@zubmit700]

This is really interesting and I love how they explain what's happening. More of them! :)

[@AussieTerra]

This is great to listen to whilst scanning neutron/black hole fields in Elite:Dangerous!

[@guardyangel]

Am i the only one extremely excited when listening to this?! 3 solar masses transformed in energy of gravitational waves! The two black holes were orbiting each other at almost the speed of light! Insane!

[@nodisalsi]

I ask a question, but apologise for not being adept at the mathematics required to answer it: Where gravity is distorting time/space, and the G-wave is a perturbation in time/space that propagates from the event that causes it, my question is this: When a distortion in time/space goes through the arms of the LIGOs, is the light beam also being effected by an equivalent blue/red shift that corresponds to the distortion of the lengths of the arms? The consequences of this is that the nullifying light beams would still be in phase no matter how large the amplitude of the G-wave was.

[@B2theENJAMIN]

can we please have an updated video with Copeland, talking about the chances of detecting his cosmic super strings, now that gravitational waves are "in the wind"

[@kevindurm5234]

IVE BEEN WAITING FOR THIS VIDEO FOR WEEKS THANK YOU THANK YOU!!

[@ParticleJesus]

What do you think the period of their orbit was? The idea of two enormous black holes moving around a point only a few kilometres wide in quick succession is absolutely terrifying to me.

[@garethdean6382]

+AugustusPugin The period was about the same as that of the waves emitted, tens of times per second at the end.

[@Fiyaaaahh]

Prof Merrifield explains we don't see "weird things" because the effects are so tiny because we are so far away. Theoretically, what kind of effects could one expect to see if we were "very close"?

[@garethdean6382]

+Fiyaaah The closer you get the smaller things are that are affected by the waves. Things would feel a 'shock' as the wave passed, stronger as you got closer. First your body would be bruised, then broken, then torn to bits. Close enough and even your atoms wouldn't be able to hold together.

[@kummarluv]

Basically timey-wimey is very wibbly-wobbly.

[@cordx5068]

+Kumar Luv Oh, you fuddy-daddy.. ;)

[@ajayreactor]

Most awaited episode on sixty symbols

[@johndrachenberg2254]

Compared to other large-scale experiments, I'd think an interferometer such as these would be relatively inexpensive to build and maintain. With even just a handful around the globe, it sounds like our understanding of gravitational waves could increase exponentially.

[@amoose136]

Not really because the tolerances on the engineering here is so very exacting and the scale is so large. Every component is mounted in a vacuum tube with active multi axis vibration cancelation on a millisecond scale. It's all incredibly precise and the actual difference in length of the arms detected was on the order of the diameter of a proton.

[@WMfin]

I always get lost here because that one professor looks like Mr. Weasley from Harry Potter but talks like Time Lord from Doctor Who and I just forget to listen because I have to think about that mix..

[@tvit]

Does space have elastic behavior? If a large object would suddenly disappear, would the curvature of space just get flat in the speed of light, or would it vibrate due to its elasticity, maybe even get negative curvature before it evens out?

[@pavphone2616]

I love it when Professor Copeland gets excited :-)

[@xmaneater]

Can you imagine the merger of these two massive black holes visually rendered in the same style as Interstellar? That would be incredible.

[@Ivo--]

The experiment reminds me of the Michaelson-Morley experiment.

[@monkeyboy4746]

+spankmeister Yes, is it possible to measure a phenomenon when the ruler you are using is undergoing the same phenomenon.

[@frankschneider6156]

+spankmeister Actually it's exactly the same technology used (well MM probably didn't use lasers, but in principle).

[@gamesbok]

MM used an oil lamp.

[@KeeganLeahy]

yay. there are my favourite videos of yours, Brady.

[@Mekratrig]

So, Professors Ed and Mike - why haven't the supar Ligo detectors detected any othar graviton waves since the initial announcement?

[@AstroMikeMerri]

They may have done: stay tuned!

[@samimas4343]

wouldn't setting up such a director on the moon give much more accurate and definitive readings?

[@samimas4343]

detector*

[@nikitakhotchenkov7406]

+Sami Mas and much more expensive also? just imagine how much stuff you should bring to the moon times cost per kilo of getting something from earth to moon, plus cost of engineering and monitoring services when thing is under construction and operational.. its much more rational to have like 40 of them here on earth, connected in one network

[@jmiquelmb]

+Sami Mas In fact, there's an european project to launch two satellites orbiting around the sun at 1000km distance each other in order to make a much more precise laser detector, if I'm not wrong. I don't know if it's been aproved or not though.

[@Hippopotatamus]

+jmiquelmb You're thinking of eLISA. It will operate in a different frequency regime, and so will be sensitive to different phenomena than aLIGO.

[@Deuce1042]

I was just at LIGO in Louisiana in March. Really cool place!

[@NeonsStyleHD]

*QUESTIONS*: *1*. How big were the gravitation waves *when* they left the system of these merging black holes? *2*. Is the gravitational waves from the moon, part of why it's moving further and further away each year?

[@frankschneider6156]

+NeonsStyle 2. To my understanding: no: the moon is continuously slowing down earths rotation via friction (thats why days get longer and longer over millions of years). As the Earth - Moon system is in first approximation a closed system, the angular momentum needs to be preserved. It is transferred to the moon, which therefore slowly moves away as earth slows down its rotation around its axis.

[@NeonsStyleHD]

Frank Schneider Thanks Frank Excellent explaination.

[@chadcastagana9181]

0:45 These aren't the gravity waves predicted by Einstein and his Theory of Relavity, these gravitational tides are described by classical physics (Newtonian Mechanics )

[@bobbynikkhah1868]

MOAR PLEASE

[@pepperspray7386]

Thank you for making the significance of this discovery clear. It's not just so scientists can high five and say "Einstein is still right homies!" It can be a way to measure and observe the universe.

[@pepperspray7386]

Reck Tominvayed Ask your mom.

[@Lexyvil]

So much energy is required for waves to occur if it's really that small and that it's equivalent to all we see in the observable universe.

[@roldanduarteholguin7102]

I want to share with NASA, ESA, Elon Musk and SpaceX the Delta Vehicle I invented on April 19, 2000: a revolutionary system that harnesses all known deltas: Pressure, Voltage, Magnetism, Density, Temperature, Height, and Gravity. The most critical aspect of my Del-ta Vehicle is the Gravitational Delta. To fully utilize Gravitational Waves, the vehicle is equipped with three specialized devices: 1. Gravitational Wave Tuner: To precisely adjust the vehicle's alignment with gravitation-al waves. 2. Gravitational Wave Amplifier: To enhance the vehicle's response to these waves. 3. Gravitational Wave Router: To direct and control the flow of gravitational energy, en-abling efficient movement and energy generation.

[@colinfew6570]

Ed has the nicest voice. Very soothing. He could do ASMR

[@Kavetrol]

I wonder why we say that something is 'astronomically small'. Things are usually astronomically big.

[@CatnamedMittens]

I was waiting for this video!

[@stefanozurich]

Is this the same Mittens from Thoorins videos?

[@CatnamedMittens]

stefanozurich Yes.

[@stefanozurich]

CatnamedMittens Cool, have a nice day.

[@CatnamedMittens]

stefanozurich You too.

[@sharonthegreat5264]

Thank very much! You answered all of my questions.

[@briansu6324]

love mike's watch

[@blackbirdpie217]

Citing spinning black hole binaries as a source for gravitational waves is the same as mistaking a spinning emergency vehicle lamp and reflector for being a blinking light. The "waves" as they interpret them are only generated by the spin of massive black holes, where the gravity is more intense in one or two directions than it is in the directions between them. What I'd like to see is finding "gravitational waves" in relatively static mass. But if the masses are static, or at least not spinning in such a way then there's no wave. I think it's a mistake to call it a wave at all.

[@MrLimitlessME]

I understand them better than most channels

[@TheSLK66]

Question: The three solar masses disappear as radiation (both thermal and gravitational), does this mean the entropy of the gravitational wave (whatever that means, since we don't know what space-time really is) is higher than the entropy of the matter it came from? Or I'm missing something here?

[@johntate6537]

+TheSLK66 OK, nice easy question - not. In all honesty, I don't absolutely know the answer to your question, but I think that the entropy of the gravitational waves does not have to be higher. For one thing, I suspect there is a problem with dealing with the gravitational waves in isolation when talking about entropy. If I remember my thermodynamics rightly, entropy, like a lot of thermodynamic quantities, is only really defined in a system that is in thermodynamic equilibrium. Since the energy of the gravitational waves is propagating out over billions of light years, the system in question is everything within that volume, and essentially none of that system is in equilibrium; so on that basis I'm guessing there is no well defined entropy. I think the other point is that, if you are asking about the ability of the system to evolve from one state to another from a thermodynamic point of view, the question is one of free energy, in which entropy is just one of the constituent parts. The main thing allowing a merger of two black holes to go ahead would be, I would think, the enormous amount of gravitational potential energy in the system. My guess would be that that is where the energy derives from. The Second Law of Thermodynamics says nothing about entropy not being able to fall if there is a source of energy to allow it. I don't know if I helped with that or just managed to confuse myself more.

[@TheSLK66]

John Tate I think you're confused in a few things. Entropy always increases, it's not only about equilibrium, there are non-equilibrium thermodynamics as well, and though like you mention, entropy doesn't necessarily have to increase for a given system, but taking the surroundings (the universe itself) and the system into considerations, entropy does always have to increase for that process to be possible. The 2nd law states that dS_system + dS_surroundings >= 0, if the system is closed and loses no energy, then dS_system >= 0 However, since I don't know how to define the wave, as either system or surroundings, I'm not sure how to approach this. Nevertheless, consider the universe as the closed system and entropy must always increase (what Beckenstein argued against Hawking, if black holes had no entropy, one could "throw" as many galaxies as desired into the black hole and the overall entropy of the universe should decrease, violating the 2nd law of thermodynamics). I know for a fact that radiation has a higher entropy that the matter it came from (E=mc^2, mass turns into energy [radiation, massless] but radiation then must have higher entropy to satisfy dS>=0) so my guess would be that gravitational waves are a similar case, however, we "know" what radiation is but we don't know what space-time really is, thus leading to the question, how to approach the entropy of something that you don't know anything about its nature.

[@NoahSpurrier]

At 6:50 it’s mentioned that some energy is lost as gravitational waves, so the merged black holes have less mass than what was started with. But I thought that energy could not exit a black hole (ignoring Hawking radiation). What accounts for the mass lost when black holes merge?

[@PTNLemay]

the whole thing is so exciting.

[@TheBigBigBlues]

Incredible stuff, explained perfectly.

[@d5uncr]

And now they got a Nobel Prize for the discovery.

[@screamingiraffe]

I wonder what would occur if you could shield yourself from the effects of space/time, would you just phase out of existence (anti-graviton based shielding)? No longer affected by time nor gravity

[@schnitzel438]

+screamingiraffe I'm pretty sure that's the most antisocial thing I've read

[@dhicks3]

Near the end, Dr. Copeland is talking about localizing the source, and he says the light took time to hit the second detector after the first. I suppose it was out of habit, but gravitational waves are not light, right? Is radiation an appropriate term? The waves to proceed outwards, but I'm not sure whether "radiation" like that is closely defined to light waves in physics.

[@parttroll1]

Its an incredible Universe we live in. An amazing feat of the scientists to detect these incredibly minute effects.

[@ciCCapROSTi]

Movie frozen. Well, I'm pretty sure there were no black holes in Frozen.

[@devilaverage6718]

+shinarit That's racist. :)

[@trimanemckenzie3943]

I've been waiting on this for sooooo long !

[@TheBloodgigas]

This could actually explain Deja vu

[@Zagnafain]

Ed is the asmr master.