With the recent discovery of the sound of gravitational waves, caused by supermassive black hole collision, we're so pleased to have Tessa Baker's fantastic talk on this topic to share with you all. You can watch the Q&A here: ua-cam.com/video/ZvAWb6br2OI/v-deo.html
Hi folks, thanks very much for watching, and well done to those who spotted the small snafu around 53:30. Indeed, the speed of gravity computed here should be faster than that of light by a tiny amount, so it’s about 299,792,458.0000001. No need to get excited about faster-than-light travel here, though - as I mentioned, that tiny difference can be explained by the limitations of our calculation. Please rest assured that this snafu appeared only in this talk :)
But that doesn't comport with the notion of gravitational lensing drastically lengthening the path of photons from distal stars. What is the force carrier and or medium for the gravitational wave that allows the wave to be lensed similar to photons?
There is another explanation of the difference of 2 seconds that in the progress of the neutron star merger there is a 2 second difference between the time of emission of the gravitational waves and the gamma waves. This must tell us something about the merger process. It also means that the speed of gravitational waves and gamma radiation is exactly the same (as you would expect - see my earlier comment). One way of resolving the question would be to observe a similar neutron star merger at a distance of 260 million light years and see if the time difference is still 2 seconds. Richard
@@OpenWorldRichard Are you saying that gravitational waves are following the same lensed pathway as the photons at the same speed? The photons travel a very convoluted lensed pathway much longer than the straight line pathway a supposedly non-particulate gravity energy wave must take. I believe there's substantial evidence of gravity particles that can be slowed in direct proportion to the Hubble Constant.
@@tomlakosh1833 The observations show that gravitational waves and gamma rays travel at exactly the same speed. What I am saying is that gravitational waves and photons are both wave disturbances of space and will both follow the same line of space curvature as caused by other gravitating bodies. Don't think of gravity particles but instead think of a gravitational wave as a wave disturbance of space itself. This is how gravitational waves are described by the General Theory of relativity. There is no such thing as a graviton. Richard
@@OpenWorldRichard Your explanation is self contradictory and defies logic. You say that there's a disturbance of space but fail to fully describe: an initiating force; a type of wave energy, and/or; a medium through which the wave propagates. The photon you compare to the mysterious wave has a particle form too upon wave collapse and an initiating EMF pulse to start the propagation. All other force carriers up to an alpha particle, have both a wave function and a particle so you have to radically depart from known physics to fabricate a wave that has no initiating force carrier, no identified wave parameters nor any particle form. I've developed a GUT with gluons as the force carrier for both the gravitational working fluid and the space-time viscosity working fluid that produces one or the other depending on the gluon momentum.
I don’t know why the auditorium wasn’t packed to the brim… this lecture was BRILLIANT!! She’s brilliant. I loved all the media to support the presentation: simulations, data presented and the experiment, too! Thank you!
I think the reason is because she’s not presenting anything novel. She’s taking the research from decades, and has condensed it down to this presentation. It’s a wonderful primer for those new to the fields, but nothing groundbreaking.
Inspiring. Dr. Baker has the rare quality of being able to communicate high-level physics concepts with clarity, enthusiasm and intelligence that make concepts accessible to a lay audience. In addition, her demos and high level of energy invite us to collectively experience some of the awe of the universe. Thank you Dr. Baker.
Really good explanation and the demos were great too, the cube grafic warping space time brilliant as was the electric drill creating gravitational waves and the strobe light detecting the waves themselves.
Absolutely brilliant presentation. I'm an astronomy buff and for the first time finally understood space/time as a dynamic element of the universe coupled with understanding how gravity waves can occur. Also, this is the first time I fell in love with an astronomer...
That drill/wheel/strobe light assembly demonstration was absolutely inspired. More so because you already had established the idea of the rubber sheet as being spacetime so it was a brilliant visualisation. Props to whoever thought of that. Great lecture; Thank you. PS seen the rubber sheet with masses on so many times but alway's thought "Yeah, but it happens in three dimensions. Along comes the 3D graphic. Smashing
She said Steve Mould did it. He's got his own UA-cam channel here where he does lots of similar fun demonstrations of physics. (Or sometimes just a "hey here's a cool thing, how does it work?" type video).
Empty space turns out to be like a very large block of jelly, endlessly vibrating, and rippling with the unimaginable forces of gravitational generation events.
deep gratitude for the brilliant mind and exact execution of the idea. thank you Dr. Baker, you present this extraordinary discovery with such joy and passion as if you were just a child on a playground...which I adore!...and to the channel definitely huge admirations
53:50 Not being good at math, I may embarrasse myself but something doesn't seem to add up, the gravitational wave arrives first, 2 seconds before light, but travels slower than light? What am I missing? Sure, instrument errors, but that would be something if somehow, a gravitational wave would cause the amount of space the light has to travel longer for light to arrive 2 light seconds later. The gravitational wave made the journey the light has to travel 600,000 km longer over the distance where the collision occurred?
It seems we have a long way to go. Our understanding of the universe is changing as data comes from James Webb and Gravitational Wave Observatories. Thanks a lot TheRi and Ms. Baker
What an excellent presentation. It was so clear with the information and I loved the demos. The observation of the neutron star merger using gravitational waves and light was particularly significant for particle physicists. At a distance of 130 million light years the merger event had a recession velocity of around one hundredth of the speed of light due to the expansion of space. We know that gravitational waves propagate as a wave disturbance of the medium of space. Therefore light must also travel as a wave disturbance of that medium. This contradicts the standard model of particle physics view of light as a wave in a quantum field which is independent of space. Furthermore, the observed nature of light as a wave in a medium from this experiment means that the postulates of Special Relativity must be wrong. Richard
Loved this talk and love RI for the wealth of good information that’s made available to general public to simply comprehend the depth of true scientific knowledge. Thank you RI.
Yes you have to translate the frequency into sound, similar to what a radio does with the radio waves it receives. But I think "the sound of gravitational waves" is very misleading. It's like saying "the sound of light". Gravitational waves comes in all frequencies and most of them are not audible.
Excellent explanation...amazing information and way of explaining..so energetic voice due to knowledge...very enjoyable and very informative..Great lecture..thank you.
Well, I have learnt things about the universe and been amused by funny noises. I'm taking that as a solid win. A wonderful talk from Tessa Baker, with a fab demonstration designed by UA-cam royalty, Mr Steve Mould.
53:52 ??? The denominator in the gravitational waves is less then the light and that should make the gravitational waves speed faster(50:43). (54:42 If the correct calculus with the information on that equations was shown the gravitational waves will be a little(almost nothing) faster than light. I lost myself, because in the equation gravitational waves will be faster because of those 2 seconds. One example is if I crossed the finish line 2 seconds before Usain Bolt that shows me being faster(she said that here 53:06). If I am wrong sorry, I'm just a depressed guy! Can someone explain to me?
Good spot. The calculated speed is inconsistent with the equation presented. The problem is that things are not quite that simple as stated in the lecture. There is an uncertainty in this experiment. We know that there is a bright flash of light during merger, and we know that there are gravitational waves produced during the merger, but we don't know exactly at which point during the merger the light is brightest. It probably isn't the exact same time when the gravitational wave is strongest. The best theoretical models suggest that the light flash is brightest a few seconds after the strongest gravitational waves are produced, and this is consistent with the strongest GW arriving before the brightest light. However, because we don't know exactly when the light pulse is produced - at the same time or after the GW, the result experiment has to give a range of possible speeds. Taking a 10 second uncertainty for when the light pulse actually happens, the slowest possible speed of GW is 299,792,457.999999 m (the calculation for this is that the light is assumed to appear 10 seconds late, but the GW arrive 2 sec before the light, meaning that the GW were 8 sec slower than the light) - but there is also a fastest possible speed for GW which is 299,792,458.0000002 m/s (assuming that the GW and light appear together, and the GW arrived 2 seconds ahead)
If something covers a distance in a shorter time the velocity must be greater. @54:00 shows the opposite - slightly slower. The gravity waves (GW) travel faster than light, due to the interstellar medium (widely spread gas) slowing down light ever so slightly and not affecting the GW.
I was also wondering if there was a reduction in the speed of light due to medium that wasn't affecting the gravity waves. It would make more sense to me that a small fraction of velocity was lost over 130 m light years than the offered explanation in this video that there was a 2 sec variance in the measurement of a locally simultaneous event. that seems like a very large error margin for the experiment.
Very interesting talk. A quick question: if the mass difference between the two fusing black holes is tallied for by the energy required to produce the gravity wave, how does this matter/energy escape the event horizon of either black hole?
It is not matter. It’s 100% energy, concentrated in small regions. The collision releases some of it and the event horizon of the resulting body is smaller than the sum of the two.
Great presentation! I would join Tessa’s patreon just to hear her say “Whooop. Smack Blackjack Mack with a slack backpack and ransack the flack attack rack. That’s a fact, whoooop.
If the gravitational wave arrived 2 seconds earlier, then it is travelling faster than the light. Somehow you reversed this and showed that it was travelling slower (by an infinitesimal amount). If the gravitational wave is travelling slower, how can it arrive BEFORE the light wave?
The value is known, it’s not what’s interesting. It’s just the number that makes the equation of gravitation universal, i.e. regardless of what the masses and distances are. Ask instead why it’s there and what it means.
@@Feenix102 I assume from astronomical observations. One of Newton’s groundbreaking contributions to science was that gravity (not God) rules the heavens, it’s the same force as here on earth. It’s been measured to great accuracy over the centuries. But the point is that no one knows why it’s there. Gravity has still not been explained by science. We have an improved theory, GR, but it’s incompatible with quantum mechanics and it’s ignored in the Standard Model.
Your question is wonderful. Big G was discovered after a 400 year story line involving astronomy, acceleration, small g, and kinematics (forces) and mechanics (torsion balances) 1. Apollonius of Perga (c 240-190 BC) modelled the periodic movement of the planets, Sun and Moon across the sky as epicycles (circles moving on other circles) that were centered around the earth i.e. geocentric model. 2. Nicolaus Copernicus (1473-1543) developed a different model in which the planets and earth revolved in simple circles around the Sun while keeping the moon revolving around the earth. This is the heliocentric model. 3. Galileo Galilei (1564-1642) developed concept of g=9.81m/s^2, allegedly by dropping stones at the leaning Tower of Piza. He invented the telescope and used it to discover moons orbiting around Jupiter. He used the telescope to discover the phases of Venus which showed that Venus orbits the Sun just as the moon orbits the earth. In 1633, he was put on trial for promoting the heliocentric model. 4. Tycho Brahe (1545 to 1601) collected and analysed data (angular positions in night sky) on the planets. He concluded that the data indicates that planets move in circular orbits around the Sun and the Sun orbits around the earth. 5. Yohannes Kepler (1571 to 1630) inherited and examined Tycho Brahe's data and saw that it described elliptical orbits around the Sun. He concluded that for each planet, the square of the period of orbit t^2 is proportional to the cube of the mean radius of orbit r^3. In other words, r^3/t^2 is a constant k that is the same for planets orbiting around the Sun. This is Kelper's 3rd Law. Nowadays we call it the GM constant. 6. Isaac Newton (1642-1747) analyzed Kelper's 3rd Law and deduced that if r^3/t^2 = k (GM constant), the acceleration g must be r/t^2 which means that g is inversely proportional to k/r^2. Nowadays we call it GM/r^2. 7. Newton applied Kelper's 3rd Law to the distance between the moon and the time it takes the moon to move around the earth. He calculated the GM constant for the orbit of the moon at about 350,000 km at an orbit period of 1 month. 8. Newton applied the same GM constant for the earth-moon system to an 'apple' at the surface of the earth which is 6370km from the center of the earth. 9. Newton discovered that the resulting acceleration for the 'apple' coming from the k/r^2 or GM/r^2 for the earth and moon is the same as small g = 9.8 m/s^2 (gravity, not to be confused with gravitation). From this, he concluded that the 'mechanism' that pulls apples downwards is the same mechanism holding the moon in orbit. 10. Newton had already defined force as mass times acceleration F=ma. That is why the metric units of force are [N] newtons (small n). 11. Newton applied F=ma to small g and found that there is a force of the form F=km/r^2. We now call it gravitational force. 12. Newton had already deduced that to every action force, there is an equal but opposit force. Hences the force that acts on a planet is also acting on the Sun. The force acting on the moon is also acting on the earth in the opposite direction. Hence the force is proportional to both the first mass and the second mass. F= GMm/r^2. This is now called Newton's law of universal gravitation. It exists between all bodies. 13. Robert Hooke (1635-1703) discovers Hooke's law relates deformation of an elasti. materials with the force on the material. He also gets into a controversy with Isaac Newton after claiming to have discovered the universal gravitation law before Isaac Newton. 13 14. Henry Cavendish (1731 to 1810) setup an experiment (torsion balance in a well) to measure the density of the earth using Isaac Newton's equation F=GMm/r^2. Part of his calculations involved measuring big G. His calculations led to a value of G = 6.754× 10^-11 [Nm^2/kg^2]. This is slightly above the modern value of 6.674×10^-11. NB. Torsion balances use Hooke's law in twisted form rather than stretched form. 15. My thumbs are tired from typing all this🤣
I thought we might be able to put a radio transmitter on the moon pointed to the earth and use several antenna on the Earth to continuously triangulate the distance between the earth and moon to provide a longer gravitation wavelength detection ability.
Cant it be that the stuff which makes for the fabric of space time gets less denser when it expands? Less density would mean the universe is not as static and glued together and so through inertia and movement generated during the creation things move quick faster, just when a rocket scapes earth: air is thicker than void
That was a great talk, very entertaining. This is an exciting field. You are detecting gravitational disturbances with a very large wave length. It should be possible to detect disturbances with a much higher frequency. The question would be what would create such disturbances. It should be possible to create such disturbances on earth. To achieve this you would need to be able to make a significant mass….vanish. A method to achieve this might be to use pair of large cyclotrons similar to the LHC, but set up so that two proton beams rings intersect tangentially and with the planes of the rings set at an angle to each other. I thought originally at 90 degrees but I think at 135 degrees. With one beam of protons operating at near light speed the mass energy of the beam is massive relative to the standing mass of the protons and has an imprint in the local gravitational field. If the beam is instantaneously transitioned to second cyclotron the mass energy of the beam instantaneously changes its imprint in the local gravitational field and should create two pulses in gravitational space at different angles to create a detectable gravitational disturbance. This disturbance might travel through the earth to be detected on the other side. There are no doubt all manner of reasons why you can’t flip a high energy beam from one track to another in an instant, but if you could it might be possible to use gravitational waves for modulated message transmission.
Is there a way to “see” inside a Blackhole? Maybe but “seeing” might be the wrong way to think about it. Maybe we should trying “listening”. Perhaps we should think about how it may be possible to use Gravitation Waves that intersect with a BH between us and the GW source and see how the portion of the GW that passes thru the BH differs from the portion of the same GW that passes by the BH without travelling thru its heart. If the Fabric of Spacetime is not torn apart at the Singularity then should not the GW traverse “across” the diameter of the BH. If so perhaps the time difference between the two portions of the wave would given some idea of the “depth/extent of curvature” of Spacetime imposed on Spacetime by the BH and if this were possible thereby add some knowledge about the conditions within the BH. Or maybe not.
@@DrDeuteron Thanks for taking the time to reply to me. As you may surmise from my "handle" I take the "I'm from Missouri" approach to most things. So correct me if I miss understand, but what you seem to be saying is that Spacetime itself becomes discontinuous at the EH of the BH and the energy of the GW spreads out over the EH and is lost. My question therefore is, is this Mathematical Speculation or is there empirical evidence that for this effect and if so could you direct me to same.
@@showmewhyiamwrong there's a coordinate discontinuity at the EH, but it's not physical, hence: Eddington Finkelstein coordinates. Basically, the inside of a blackhole is in our future, and since nothing goes back in time...nothing can come out.
Understanding why black holes don't allow light to escape would probably answer your question. Imagine falling into a well. You go to climb out, but the well gets deeper, faster than you can climb so even though you are moving into the direction "up" the space you are in is expanding faster than light can travel. There is an observational bias that tells us that a black hole is a discrete region of space where a star once exploded. The reality is far more interesting. A black hole is a region we see as having an outer boundary, but past that boundary, space is EXPANDING faster than light can travel through it. The further past the event boundary you travel, the faster the spatial metric expands. The bias is to see it as a fixed radius that makes being compressed to a point, inevitable... but the distance from the event boundary to what we see as the radius, is expanding exponentially. You could never reach the center you would be so certain must exist from outside observation. For the same reason, gravitational waves would have an infinite expanding space to propagate through... The space outside the event horizon would interact with the universe, but beyond the event horizon, it's just a maximum entropy path no different than the outer edge of our own universe. Energy that dissipates to entropy isn't shocking in it being lost to useful interaction with universe. Being lost to a black hole isn't shocking or weird in any way either.
Could the speed difference be a result of them using the equation wrong? If light has to follow the curvature of space, is it possible that gravity is taking a shorter route?
@53:40 there's an inconsistency in the presentation - either gravitational waves looked to be faster than light OR they arrived after 130 million years PLUS 2 seconds. Otherwise, great talk!
Nikola Tesla - 'If you want to find the secrets of the universe, think in terms of energy, frequency and vibration.' only an hour yet weeks worth of mulling over data for the brain, there is so much more to that study, talks like these where people from different perspectives and fields can maybe look at their own field and come up with new ideas, is just so cool I am looking at this from electrical design & engineering, I am also a Ham Radio Operator this all makes so much sense in many fields...
@@Mrphilipjcook I think even the best scientists ultimately understand most things as analogies - this is part of the reason quantum mechanics seems so weird to us, we don't have very many human-scale phenomena that analogize well! The actual mathematics is fairly straightforward and, in its own way, logical enough. I was honestly thinking more about the odd parallel between these two great discoveries about gravity, plus of course the escalating scale of brutality. (Not that I would draw any particular significance from that, it's just kind of funny.)
nothing would happen. GW amplitude falls off linearly, so the strain would be 10ly/1Bly = 100 million times bigger than GW20140914...which is around 10^-11 meters.
Why does this require a black hole or neutron star. I am assuming the star(s) that end up forming either on of these will be more massive and should cause gravitational waves. If that is the case these waves should be there everywhere where we have a binary star system. And extending loss of energy logic those two binary starts should merge to form one as well (unless time for this to happen is longer than TTL of the stars in question).
Black holes aren’t more massive than the stars they come from. Just smaller. It’s the concentration (their radius) that makes them black, not the mass.
I understand the mass part. My question was why does only binary neutron stars or blackholes generate gravitational waves and not the original starts from which these neutron start or black holes came. In fact in case of the starts in binary system more mass is going in circles (a part of starts mass is lost during supernova after which neutron start or blackhole forms).
@@tyagitindall9531 Binary stars are torn apart before coming close to the velocities of dead stars. The only reason we can detect the g waves is that ultra-compact bodies reach insane speeds when falling toward each other which gives the waves higher frequencies.
I think she forgot about cosmic-ray observatories that look at various sources of high energy particles, not just light. Light/radio astronomy has more in common with gravitational wave astronomy than it does with things looking for particles with mass. It's still very exciting, however.
Probably could dump several paragraphs of comments in half a second but paused the presentation to ask.. 3 solar masses.. is it at all possible that some of it is matter being ejected or do the two black hole object's reaching stupendous orbital speeds still have enough gravity to cling on to all the matter within their respective event horizons. And at what point would they be blown off or what happens to the accretion disks when neutron stars and black holes merge.
@@DominicRyanOsborne "No mass" is incorrect. They obviously have a lot of mass. Which is energy. All the matter of the star burned up in fusion, was emitted in a supernova, turned into gamma rays. The rest crunched. Btw orbiting black holes/neutron stars have no accretion disks. That stuff is long gone. You know what matter is, don't you?
@@DominicRyanOsborne Mass is a measure of energy-content. They are the same thing. Black holes are 100% EM energy at maximal frequency. You can call a black hole one big particle if you want, but there is definitely no separation into the fundamental particles (electrons, protons, etc.) that we know.
Out of respect for your speakers and for the benefit of your video audience, would you please print the speaker's name in the closing credits, along with the tiitle of any book being promoted?
At the beginning of the video: isn't it wrong to describe an imaginary gravity wave as a spiral when in reality it is like a pulsating wave? That's how it should be perceived here, right? The amplitude of the change in intensity decreasing as the objects approach each other?
If you exchange "violin" for "passion", I think he is right. All are metaphors. A table - a place to work. A chair - a place to rest. A bowl of fruit - sustenance. A violin - a reason for living. He was smarter than me - I suspect his words have deeper meaning.
I can’t help but wonder what happens if you attempt a double slit with gravity. Is such a thing possible even? I’m not smart enough to do more than wonder.
With the recent discovery of the sound of gravitational waves, caused by supermassive black hole collision, we're so pleased to have Tessa Baker's fantastic talk on this topic to share with you all. You can watch the Q&A here: ua-cam.com/video/ZvAWb6br2OI/v-deo.html
What is the force carrier and/or medium for the gravitational wave that allows the wave to be lensed similar to photons?
😢Optimism is a force. I see repetition at low level. Basic things. 🙏
Só, whatever, I have children, thank you! G
Hi folks, thanks very much for watching, and well done to those who spotted the small snafu around 53:30. Indeed, the speed of gravity computed here should be faster than that of light by a tiny amount, so it’s about 299,792,458.0000001.
No need to get excited about faster-than-light travel here, though - as I mentioned, that tiny difference can be explained by the limitations of our calculation.
Please rest assured that this snafu appeared only in this talk :)
But that doesn't comport with the notion of gravitational lensing drastically lengthening the path of photons from distal stars. What is the force carrier and or medium for the gravitational wave that allows the wave to be lensed similar to photons?
There is another explanation of the difference of 2 seconds that in the progress of the neutron star merger there is a 2 second difference between the time of emission of the gravitational waves and the gamma waves. This must tell us something about the merger process. It also means that the speed of gravitational waves and gamma radiation is exactly the same (as you would expect - see my earlier comment). One way of resolving the question would be to observe a similar neutron star merger at a distance of 260 million light years and see if the time difference is still 2 seconds. Richard
@@OpenWorldRichard Are you saying that gravitational waves are following the same lensed pathway as the photons at the same speed? The photons travel a very convoluted lensed pathway much longer than the straight line pathway a supposedly non-particulate gravity energy wave must take. I believe there's substantial evidence of gravity particles that can be slowed in direct proportion to the Hubble Constant.
@@tomlakosh1833 The observations show that gravitational waves and gamma rays travel at exactly the same speed. What I am saying is that gravitational waves and photons are both wave disturbances of space and will both follow the same line of space curvature as caused by other gravitating bodies. Don't think of gravity particles but instead think of a gravitational wave as a wave disturbance of space itself. This is how gravitational waves are described by the General Theory of relativity. There is no such thing as a graviton. Richard
@@OpenWorldRichard Your explanation is self contradictory and defies logic. You say that there's a disturbance of space but fail to fully describe: an initiating force; a type of wave energy, and/or; a medium through which the wave propagates. The photon you compare to the mysterious wave has a particle form too upon wave collapse and an initiating EMF pulse to start the propagation. All other force carriers up to an alpha particle, have both a wave function and a particle so you have to radically depart from known physics to fabricate a wave that has no initiating force carrier, no identified wave parameters nor any particle form. I've developed a GUT with gluons as the force carrier for both the gravitational working fluid and the space-time viscosity working fluid that produces one or the other depending on the gluon momentum.
I don’t know why the auditorium wasn’t packed to the brim… this lecture was BRILLIANT!! She’s brilliant. I loved all the media to support the presentation: simulations, data presented and the experiment, too! Thank you!
I'm 12 using brothers phone, are you same age mabe close? Probably older 14 u seem smarter ❤
I think the reason is because she’s not presenting anything novel. She’s taking the research from decades, and has condensed it down to this presentation. It’s a wonderful primer for those new to the fields, but nothing groundbreaking.
@@keefjunior4061 lol ouch but true
great talk, i can not wait for Tessa to come back and explain the recent announcement on gravitational background using pulsars.
Brilliant presentation as usual. Never disappoints this channel it’s the best sub I ever did 👏🏻
Inspiring. Dr. Baker has the rare quality of being able to communicate high-level physics concepts with clarity, enthusiasm and intelligence that make concepts accessible to a lay audience. In addition, her demos and high level of energy invite us to collectively experience some of the awe of the universe. Thank you Dr. Baker.
I was at this talk! I really loved being there!
One of the finest presentations on any subject I have ever seen! Thanks to everyone involved.
what an ingenious way of demonstrating gravitational waves!
It was fantastic!!!!!!!!!
It was just as good as when the guy first did it 10-20 years ago.
Your åæ buggż
Really good explanation and the demos were great too, the cube grafic warping space time brilliant as was the electric drill creating gravitational waves and the strobe light detecting the waves themselves.
Showing spacetime as a cube really helps in visualization of spacetime.
Excellent presentation.
Brilliant lecture and well presented for the amateur layman.
I've been a layman for a long time, so I consider myself a professional layman.
A remarkable presentation! Very interesting and the presenter made it so easy to grasp the concepts.
Absolutely brilliant presentation. I'm an astronomy buff and for the first time finally understood space/time as a dynamic element of the universe coupled with understanding how gravity waves can occur. Also, this is the first time I fell in love with an astronomer...
That drill/wheel/strobe light assembly demonstration was absolutely inspired. More so because you already had established the idea of the rubber sheet as being spacetime so it was a brilliant visualisation. Props to whoever thought of that. Great lecture; Thank you. PS seen the rubber sheet with masses on so many times but alway's thought "Yeah, but it happens in three dimensions. Along comes the 3D graphic. Smashing
She said Steve Mould did it. He's got his own UA-cam channel here where he does lots of similar fun demonstrations of physics. (Or sometimes just a "hey here's a cool thing, how does it work?" type video).
Absolutely@@bryan__m , I've seen a lot of Steve Mould's stuff. What an excellent educator. BW
@@terencechipchase1761 awesome!
She's so pasionate! I wish I had at least one teacher like her 😔
great presentation! Thank you! i loved the demonstrations!
Empty space turns out to be like a very large block of jelly, endlessly vibrating, and rippling with the unimaginable forces of gravitational generation events.
What a brilliant presentation 👍
What a beautiful, beautiful talk.
Absolutely brilliant lecture. Thank you
What a great presentation! Thank you so much! 😊
Such a beautiful presentation... I wish, i had a teacher like her in my school time.
Loving every minute! Amazing job!
This is amazing
Absolutely brilliant lecture. Thank you angel.
The 'woke' brigade will be after me now! Gotta go. 😉
good show Tessa, well done Dan
Fascinating topic and exciting to follow.
Great program ,thanks for the hard work in research and getting the highlights across; Jon~ Pennsylvania
How something that arrives first comes out as slower? 53:40
That was a great demonstration with the drill.
deep gratitude for the brilliant mind and exact execution of the idea. thank you Dr. Baker, you present this extraordinary discovery with such joy and passion as if you were just a child on a playground...which I adore!...and to the channel definitely huge admirations
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That rubber sheet two-body demonstration is the best one yet !!!
Much more impressive than the usual handling of that issue.
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53:50 Not being good at math, I may embarrasse myself but something doesn't seem to add up, the gravitational wave arrives first, 2 seconds before light, but travels slower than light? What am I missing?
Sure, instrument errors, but that would be something if somehow, a gravitational wave would cause the amount of space the light has to travel longer for light to arrive 2 light seconds later. The gravitational wave made the journey the light has to travel 600,000 km longer over the distance where the collision occurred?
I agree with you. Even such simple maths can be messed up by physicist.
The script should say light arrives 2 seconds before gravitational waves but she just forgot and swapped them.
It seems we have a long way to go. Our understanding of the universe is changing as data comes from James Webb and Gravitational Wave Observatories.
Thanks a lot TheRi and Ms. Baker
What an excellent presentation. It was so clear with the information and I loved the demos. The observation of the neutron star merger using gravitational waves and light was particularly significant for particle physicists. At a distance of 130 million light years the merger event had a recession velocity of around one hundredth of the speed of light due to the expansion of space. We know that gravitational waves propagate as a wave disturbance of the medium of space. Therefore light must also travel as a wave disturbance of that medium. This contradicts the standard model of particle physics view of light as a wave in a quantum field which is independent of space. Furthermore, the observed nature of light as a wave in a medium from this experiment means that the postulates of Special Relativity must be wrong. Richard
Thank you very much for the video.
Loved this talk and love RI for the wealth of good information that’s made available to general public to simply comprehend the depth of true scientific knowledge. Thank you RI.
Great explanation of gravitational waves! Thank you
I had no idea we could hear gravitational waves! Thanks for the education. Awesome presentation.
If i understood corretly then its a translation into sound, a representation of what they would sound if they were sound.
Yes you have to translate the frequency into sound, similar to what a radio does with the radio waves it receives.
But I think "the sound of gravitational waves" is very misleading. It's like saying "the sound of light". Gravitational waves comes in all frequencies and most of them are not audible.
I will believe in anything coming out of NASA after they revisit the Moon.
That demonstration with the drill on the fabric was great. Fairly easy way to show how gravitational waves work.
Well presented 👏
I am a fan of this channel. Right now 278 views, 10 minutes ago uploaded. Feeling good to be one of the first few viewers.
Excellent explanation...amazing information and way of explaining..so energetic voice due to knowledge...very enjoyable and very informative..Great lecture..thank you.
Great talk, she's has an amazing job
Clara, divertida, detallada.... qué charla más buena!
only 45 seconds in and wow, what a great speaker!
Thank you, Tessa. Amazing !
An exellent explanation!
The app mentioned in lecture....
iPhone users - GW Events
Android users - Astro-COLIBRI
Well, I have learnt things about the universe and been amused by funny noises. I'm taking that as a solid win. A wonderful talk from Tessa Baker, with a fab demonstration designed by UA-cam royalty, Mr Steve Mould.
53:52 ??? The denominator in the gravitational waves is less then the light and that should make the gravitational waves speed faster(50:43). (54:42 If the correct calculus with the information on that equations was shown the gravitational waves will be a little(almost nothing) faster than light. I lost myself, because in the equation gravitational waves will be faster because of those 2 seconds. One example is if I crossed the finish line 2 seconds before Usain Bolt that shows me being faster(she said that here 53:06). If I am wrong sorry, I'm just a depressed guy! Can someone explain to me?
Good spot. The calculated speed is inconsistent with the equation presented.
The problem is that things are not quite that simple as stated in the lecture. There is an uncertainty in this experiment. We know that there is a bright flash of light during merger, and we know that there are gravitational waves produced during the merger, but we don't know exactly at which point during the merger the light is brightest. It probably isn't the exact same time when the gravitational wave is strongest.
The best theoretical models suggest that the light flash is brightest a few seconds after the strongest gravitational waves are produced, and this is consistent with the strongest GW arriving before the brightest light.
However, because we don't know exactly when the light pulse is produced - at the same time or after the GW, the result experiment has to give a range of possible speeds. Taking a 10 second uncertainty for when the light pulse actually happens, the slowest possible speed of GW is 299,792,457.999999 m (the calculation for this is that the light is assumed to appear 10 seconds late, but the GW arrive 2 sec before the light, meaning that the GW were 8 sec slower than the light) - but there is also a fastest possible speed for GW which is 299,792,458.0000002 m/s (assuming that the GW and light appear together, and the GW arrived 2 seconds ahead)
Great stuff
Great imitation of the gravitational sounds! Appreciate the knowledge being passed on.
If something covers a distance in a shorter time the velocity must be greater. @54:00 shows the opposite - slightly slower.
The gravity waves (GW) travel faster than light, due to the interstellar medium (widely spread gas) slowing down light ever so slightly and not affecting the GW.
I was also wondering if there was a reduction in the speed of light due to medium that wasn't affecting the gravity waves. It would make more sense to me that a small fraction of velocity was lost over 130 m light years than the offered explanation in this video that there was a 2 sec variance in the measurement of a locally simultaneous event. that seems like a very large error margin for the experiment.
I am wonderfully informed -
And so terribly charmed!
Respected madam..Gravitational wave events app not found in play store as you suggested..please guide me that how can I get the app .thanks
Im not able to find The Gravitational wave event app, is it no longer running?
Very interesting talk. A quick question: if the mass difference between the two fusing black holes is tallied for by the energy required to produce the gravity wave, how does this matter/energy escape the event horizon of either black hole?
It is not matter. It’s 100% energy, concentrated in small regions. The collision releases some of it and the event horizon of the resulting body is smaller than the sum of the two.
Great presentation! I would join Tessa’s patreon just to hear her say “Whooop. Smack Blackjack Mack with a slack backpack and ransack the flack attack rack. That’s a fact, whoooop.
Cool!
If the gravitational wave arrived 2 seconds earlier, then it is travelling faster than the light. Somehow you reversed this and showed that it was travelling slower (by an infinitesimal amount). If the gravitational wave is travelling slower, how can it arrive BEFORE the light wave?
After all tese years ,finally an explanation of GW that I can understand ..Thank you Dr Baker 🙂
I'm interested in the constant, G. What is the value of it and how did Newton arrive at that? Fascinating talk. :)
The value is known, it’s not what’s interesting. It’s just the number that makes the equation of gravitation universal, i.e. regardless of what the masses and distances are. Ask instead why it’s there and what it means.
@@dodatroda Well yes, how was it arrived at?
@@Feenix102 I assume from astronomical observations. One of Newton’s groundbreaking contributions to science was that gravity (not God) rules the heavens, it’s the same force as here on earth.
It’s been measured to great accuracy over the centuries. But the point is that no one knows why it’s there. Gravity has still not been explained by science. We have an improved theory, GR, but it’s incompatible with quantum mechanics and it’s ignored in the Standard Model.
Your question is wonderful.
Big G was discovered after a 400 year story line involving astronomy, acceleration, small g, and kinematics (forces) and mechanics (torsion balances)
1. Apollonius of Perga (c 240-190 BC) modelled the periodic movement of the planets, Sun and Moon across the sky as epicycles (circles moving on other circles) that were centered around the earth i.e. geocentric model.
2. Nicolaus Copernicus (1473-1543) developed a different model in which the planets and earth revolved in simple circles around the Sun while keeping the moon revolving around the earth. This is the heliocentric model.
3. Galileo Galilei (1564-1642) developed concept of g=9.81m/s^2, allegedly by dropping stones at the leaning Tower of Piza. He invented the telescope and used it to discover moons orbiting around Jupiter. He used the telescope to discover the phases of Venus which showed that Venus orbits the Sun just as the moon orbits the earth. In 1633, he was put on trial for promoting the heliocentric model.
4. Tycho Brahe (1545 to 1601) collected and analysed data (angular positions in night sky) on the planets. He concluded that the data indicates that planets move in circular orbits around the Sun and the Sun orbits around the earth.
5. Yohannes Kepler (1571 to 1630) inherited and examined Tycho Brahe's data and saw that it described elliptical orbits around the Sun. He concluded that for each planet, the square of the period of orbit t^2 is proportional to the cube of the mean radius of orbit r^3. In other words, r^3/t^2 is a constant k that is the same for planets orbiting around the Sun. This is Kelper's 3rd Law. Nowadays we call it the GM constant.
6. Isaac Newton (1642-1747) analyzed Kelper's 3rd Law and deduced that if r^3/t^2 = k (GM constant), the acceleration g must be r/t^2 which means that g is inversely proportional to k/r^2. Nowadays we call it GM/r^2.
7. Newton applied Kelper's 3rd Law to the distance between the moon and the time it takes the moon to move around the earth. He calculated the GM constant for the orbit of the moon at about 350,000 km at an orbit period of 1 month.
8. Newton applied the same GM constant for the earth-moon system to an 'apple' at the surface of the earth which is 6370km from the center of the earth.
9. Newton discovered that the resulting acceleration for the 'apple' coming from the k/r^2 or GM/r^2 for the earth and moon is the same as small g = 9.8 m/s^2 (gravity, not to be confused with gravitation). From this, he concluded that the 'mechanism' that pulls apples downwards is the same mechanism holding the moon in orbit.
10. Newton had already defined force as mass times acceleration F=ma. That is why the metric units of force are [N] newtons (small n).
11. Newton applied F=ma to small g and found that there is a force of the form F=km/r^2. We now call it gravitational force.
12. Newton had already deduced that to every action force, there is an equal but opposit force. Hences the force that acts on a planet is also acting on the Sun. The force acting on the moon is also acting on the earth in the opposite direction. Hence the force is proportional to both the first mass and the second mass. F= GMm/r^2. This is now called Newton's law of universal gravitation. It exists between all bodies.
13. Robert Hooke (1635-1703) discovers Hooke's law relates deformation of an elasti. materials with the force on the material. He also gets into a controversy with Isaac Newton after claiming to have discovered the universal gravitation law before Isaac Newton.
13
14. Henry Cavendish (1731 to 1810) setup an experiment (torsion balance in a well) to measure the density of the earth using Isaac Newton's equation F=GMm/r^2. Part of his calculations involved measuring big G. His calculations led to a value of G = 6.754× 10^-11 [Nm^2/kg^2]. This is slightly above the modern value of 6.674×10^-11.
NB. Torsion balances use Hooke's law in twisted form rather than stretched form.
15. My thumbs are tired from typing all this🤣
Thankyou for a very full and comprehensive answer! As a layman with an interest in the subject, I am grateful. :o)
This is very interesting
I thought we might be able to put a radio transmitter on the moon pointed to the earth and use several antenna on the Earth to continuously triangulate the distance between the earth and moon to provide a longer gravitation wavelength detection ability.
Cant it be that the stuff which makes for the fabric of space time gets less denser when it expands? Less density would mean the universe is not as static and glued together and so through inertia and movement generated during the creation things move quick faster, just when a rocket scapes earth: air is thicker than void
ty )
Any suggestions for an Android GWE app?
That was a great talk, very entertaining. This is an exciting field. You are detecting gravitational disturbances with a very large wave length. It should be possible to detect disturbances with a much higher frequency. The question would be what would create such disturbances. It should be possible to create such disturbances on earth. To achieve this you would need to be able to make a significant mass….vanish. A method to achieve this might be to use pair of large cyclotrons similar to the LHC, but set up so that two proton beams rings intersect tangentially and with the planes of the rings set at an angle to each other. I thought originally at 90 degrees but I think at 135 degrees. With one beam of protons operating at near light speed the mass energy of the beam is massive relative to the standing mass of the protons and has an imprint in the local gravitational field. If the beam is instantaneously transitioned to second cyclotron the mass energy of the beam instantaneously changes its imprint in the local gravitational field and should create two pulses in gravitational space at different angles to create a detectable gravitational disturbance. This disturbance might travel through the earth to be detected on the other side. There are no doubt all manner of reasons why you can’t flip a high energy beam from one track to another in an instant, but if you could it might be possible to use gravitational waves for modulated message transmission.
Is there a way to “see” inside a Blackhole? Maybe but “seeing” might be the wrong way to think about it. Maybe we should trying “listening”. Perhaps we should think about how it may be possible to use Gravitation Waves that intersect with a BH between us and the GW source and see how the portion of the GW that passes thru the BH differs from the portion of the same GW that passes by the BH without travelling thru its heart. If the Fabric of Spacetime is not torn apart at the Singularity then should not the GW traverse “across” the diameter of the BH. If so perhaps the time difference between the two portions of the wave would given some idea of the “depth/extent of curvature” of Spacetime imposed on Spacetime by the BH and if this were possible thereby add some knowledge about the conditions within the BH. Or maybe not.
GWs don't pass through a blackhole, so blackhole tomography is not going to work...good idea though.
@@DrDeuteron Thanks for taking the time to reply to me. As you may surmise from my "handle" I take the "I'm from Missouri" approach to most things. So correct me if I miss understand, but what you seem to be saying is that Spacetime itself becomes discontinuous at the EH of the BH and the energy of the GW spreads out over the EH and is lost. My question therefore is, is this Mathematical Speculation or is there empirical evidence that for this effect and if so could you direct me to same.
@@showmewhyiamwrong there's a coordinate discontinuity at the EH, but it's not physical, hence: Eddington Finkelstein coordinates.
Basically, the inside of a blackhole is in our future, and since nothing goes back in time...nothing can come out.
Understanding why black holes don't allow light to escape would probably answer your question.
Imagine falling into a well.
You go to climb out, but the well gets deeper, faster than you can climb so even though you are moving into the direction "up" the space you are in is expanding faster than light can travel.
There is an observational bias that tells us that a black hole is a discrete region of space where a star once exploded.
The reality is far more interesting.
A black hole is a region we see as having an outer boundary, but past that boundary, space is EXPANDING faster than light can travel through it.
The further past the event boundary you travel, the faster the spatial metric expands.
The bias is to see it as a fixed radius that makes being compressed to a point, inevitable... but the distance from the event boundary to what we see as the radius, is expanding exponentially.
You could never reach the center you would be so certain must exist from outside observation.
For the same reason, gravitational waves would have an infinite expanding space to propagate through...
The space outside the event horizon would interact with the universe, but beyond the event horizon, it's just a maximum entropy path no different than the outer edge of our own universe. Energy that dissipates to entropy isn't shocking in it being lost to useful interaction with universe.
Being lost to a black hole isn't shocking or weird in any way either.
After seeing and hearing, the next step is to taste the universe !
Please make the sound a bit louder.🥺
Could the speed difference be a result of them using the equation wrong? If light has to follow the curvature of space, is it possible that gravity is taking a shorter route?
@53:40 there's an inconsistency in the presentation - either gravitational waves looked to be faster than light OR they arrived after 130 million years PLUS 2 seconds. Otherwise, great talk!
I catch that too!
Of what is Space-Time composed? What is being distorted by the gravitational waves?
Nikola Tesla - 'If you want to find the secrets of the universe, think in terms of energy, frequency and vibration.'
only an hour yet weeks worth of mulling over data for the brain, there is so much more to that study, talks like these where people from different perspectives and fields can maybe look at their own field and come up with new ideas, is just so cool
I am looking at this from electrical design & engineering, I am also a Ham Radio Operator this all makes so much sense in many fields...
I could listen to "silly" blackhole sounds all day!
Interesting
Based on the thumbnail: I like imagining that she’s gesturing a wave with her arm and making a sound effect with her mouth :)
Funny that Newton credits one of his key insights to the occasion of an apple falling from a tree, and Einstein to a man falling off a roof.
It's easier to sell an idea as a story, perhaps. People like an analogy.
@@Mrphilipjcook I think even the best scientists ultimately understand most things as analogies - this is part of the reason quantum mechanics seems so weird to us, we don't have very many human-scale phenomena that analogize well! The actual mathematics is fairly straightforward and, in its own way, logical enough.
I was honestly thinking more about the odd parallel between these two great discoveries about gravity, plus of course the escalating scale of brutality. (Not that I would draw any particular significance from that, it's just kind of funny.)
Thanks England for a wise astronomy enterprize, we are definitely on the verge of a new era.
44:33
how is it possible that gamma rays can get but light can't get out?
I wonder what it would be like if one happened to be close to (within maybe 10 light years ) to a merger. Would it pretty much destroy things?
nothing would happen. GW amplitude falls off linearly, so the strain would be 10ly/1Bly = 100 million times bigger than GW20140914...which is around 10^-11 meters.
We live in exciting times.
42:27
I'm still waiting on a detection of a single neutron star becoming a black hole...
Why does this require a black hole or neutron star. I am assuming the star(s) that end up forming either on of these will be more massive and should cause gravitational waves. If that is the case these waves should be there everywhere where we have a binary star system. And extending loss of energy logic those two binary starts should merge to form one as well (unless time for this to happen is longer than TTL of the stars in question).
Black holes aren’t more massive than the stars they come from. Just smaller. It’s the concentration (their radius) that makes them black, not the mass.
I understand the mass part. My question was why does only binary neutron stars or blackholes generate gravitational waves and not the original starts from which these neutron start or black holes came. In fact in case of the starts in binary system more mass is going in circles (a part of starts mass is lost during supernova after which neutron start or blackhole forms).
@@tyagitindall9531 Binary stars are torn apart before coming close to the velocities of dead stars. The only reason we can detect the g waves is that ultra-compact bodies reach insane speeds when falling toward each other which gives the waves higher frequencies.
3:00 neutrinos? One could argue that collecting meteorites is "solid object astronomy".
I think she forgot about cosmic-ray observatories that look at various sources of high energy particles, not just light. Light/radio astronomy has more in common with gravitational wave astronomy than it does with things looking for particles with mass. It's still very exciting, however.
Probably could dump several paragraphs of comments in half a second but paused the presentation to ask.. 3 solar masses.. is it at all possible that some of it is matter being ejected or do the two black hole object's reaching stupendous orbital speeds still have enough gravity to cling on to all the matter within their respective event horizons. And at what point would they be blown off or what happens to the accretion disks when neutron stars and black holes merge.
There is no matter in black holes.
@@dodatroda today I learned some of the most massive objects in the universe have no mass because they are not made of matter
@@DominicRyanOsborne "No mass" is incorrect. They obviously have a lot of mass. Which is energy.
All the matter of the star burned up in fusion, was emitted in a supernova, turned into gamma rays. The rest crunched.
Btw orbiting black holes/neutron stars have no accretion disks. That stuff is long gone.
You know what matter is, don't you?
@@dodatroda the energy within a given space, formed into fundamental particles with higgs bosons to provide mass to the system
@@DominicRyanOsborne Mass is a measure of energy-content. They are the same thing. Black holes are 100% EM energy at maximal frequency.
You can call a black hole one big particle if you want, but there is definitely no separation into the fundamental particles (electrons, protons, etc.) that we know.
Why such a small crowd? Normally the RI is packed, and it should have been for this too.
Out of respect for your speakers and for the benefit of your video audience, would you please print the speaker's name in the closing credits, along with the tiitle of any book being promoted?
At the beginning of the video:
isn't it wrong to describe an imaginary gravity wave as a spiral when in reality it is like a pulsating wave?
That's how it should be perceived here, right?
The amplitude of the change in intensity decreasing as the objects approach each other?
If you exchange "violin" for "passion", I think he is right.
All are metaphors. A table - a place to work. A chair - a place to rest. A bowl of fruit - sustenance. A violin - a reason for living.
He was smarter than me - I suspect his words have deeper meaning.
I can’t help but wonder what happens if you attempt a double slit with gravity. Is such a thing possible even? I’m not smart enough to do more than wonder.
you look amazing dr. Baker, good productive talk.
The 'woke' brigade will be after me!! 😉
What do radio waves taste like?
If gravity is faster ,,, why is the distance per second smaller ?
In one moment she said that was faster and after she said that light was faster...
If the Gravitational Waves arrived 2 seconds earlier, how could they have been travelling slower than the light??