Scientists can explore the cosmos in revolutionary new ways with the help of gravitational waves, and their discoveries are unravelling the universe's greatest mysteries.
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Thansk for watching. Follow for more videos.
#cosmosspacescience
#howtheuniverseworks
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LearningTranscript
00:00First, there was light. Visible light.
00:07Then, we viewed the universe in radio waves and x-rays.
00:13Ever since there's been astronomy, we've been looking at different kinds of light
00:19and opening up the universe a little bit more at a time.
00:24But then in 2015, like the roof came off.
00:29Something happened that changed everything.
00:32The ability to see waves in space and time itself.
00:36Gravitational waves.
00:38They help us roll back the clock to the dawn of time,
00:42discover epic cosmic collisions,
00:46and make earth-shaking discoveries.
00:49Gravitational waves are the biggest game-changer since the invention of the telescope.
00:54We have a completely new universe to view now.
00:57A new exploration of space is just beginning.
01:12Long ago, 17 billion light-years away, a cataclysmic showdown plays out.
01:21Two black holes locked together in a deadly cosmic dance.
01:27Black holes are unimaginably dense objects with gravity so intense that if you get too close to them, you're gone.
01:34Their immense gravitational pull causes them to spiral towards each other.
01:46When black holes collide, they don't just run into each other.
01:49They're in orbit about each other.
01:51So what we're talking about is an in-spiraling orbit that goes faster and faster and faster and faster.
01:59Until they finally collide in a fatal embrace.
02:04But astronomers don't see a thing.
02:11The problem with observing colliding black holes is all about the name.
02:15Black holes that give off no light.
02:17How can astronomers see something that no telescope can detect?
02:21Across the universe, extraordinary events take place.
02:27But we sometimes miss them because we rely on light.
02:34Now, astronomers have a new tool kit that's revealing the cosmos in a totally different way.
02:44Using the very fabric of our universe we call space-time.
02:50Everything with mass, like stars, planets, and black holes, all curve this fabric.
03:00The more massive the object, the bigger the distortion of space-time.
03:05The classical analogy is this stretched rubber sheet, right?
03:09And like a mass, like the sun is like a ball on this sheet and it distorts and warps the sheet into this valley, right?
03:16And if you roll a marble across it, like the marble is a planet,
03:20the marble will be pulled into orbit around the ball because of the curvature of the sheet.
03:29But that's only half the picture.
03:31If an object has mass and is accelerating through space-time,
03:36it creates ripples in that fabric of space-time.
03:39And we call these gravitational waves.
03:42Gravitational waves give us vital clues about distant objects that we can't see.
03:49The more massive the object that produces them,
03:53and the faster it's moving, the bigger the ripples.
03:57These ripples pass through planets, stars, and galaxies with ease.
04:03When a gravitational wave passes through an object, like a star or a planet or a person,
04:10it stretches and compresses them, like with this tennis ball.
04:14Now, if you're close to a powerful source of gravitational waves,
04:19like merging supermassive black holes, those waves are incredibly strong,
04:23and they're capable of actually destroying a planet.
04:26But, like the ripples on a pond, their strength and size diminishes over distance.
04:33The farther away you are, the weaker they get.
04:37And when they're hundreds of millions of light-years away,
04:39they're actually smaller than the size of an atom.
04:42So, to listen for gravitational waves,
04:45scientists built the most sensitive measuring device on the planet.
04:49This is LIGO, the Laser Interferometer Gravitational Wave Observatory.
05:03Two enormous detectors located almost 2,000 miles apart in Louisiana and Washington State.
05:12Each sensor has L-shaped arms, measuring two and a half miles.
05:19Inside the LIGO detectors, inside these concrete tunnels, there is a laser system.
05:26It's called an interferometer.
05:28So, light comes in from a laser beam and is split into two paths.
05:35Normally, the lengths of the two beams are the same.
05:41That changes when gravitational waves hit the beams.
05:46When a gravitational wave passes through, it changes the distance that light travels along these arms.
05:54So, one arm effectively gets longer and the other one gets shorter.
05:59The length of those two beams varies just ever so slightly,
06:04and the very sensitive apparatus in LIGO is able to pick that up.
06:08With this ultra-sensitive laser system, LIGO picks up distortions in space-time,
06:15narrower than one millionth of the diameter of an atom.
06:20Just that feat, just the fact that we were able to build a detector to detect gravitational waves,
06:26is just mind-boggling.
06:29All of a sudden now, we were listening to the faintest whispers of the universe.
06:36In 2015, LIGO picked up a whisper that had been traveling towards Earth for over a billion years.
06:42Its source? Two colliding stellar black holes.
06:48Watching two black holes spiral in and merge, that's not something we can do using optical telescopes,
06:55or X-ray telescopes, or anything like that.
06:57But, with LIGO, we could actually detect that event.
07:01Now, scientists can paint accurate pictures of invisible objects.
07:16You can tell. You're looking at black holes. You can get their masses. You can get their distance.
07:23There's a phenomenal amount of information in that wave.
07:29The colliding black holes are the most massive LIGO has ever detected.
07:34One is 66 times the mass of our Sun.
07:38The other, 85 times the mass of our Sun.
07:43As two black holes are spiraling in, they are moving faster and faster as they get closer and closer.
07:49That means that the gravitational waves they are emitting have a higher and higher frequency.
07:54So, as time goes on, the pitch gets higher.
07:57So, it goes...
08:08When they finally merge, they create a giant.
08:12By analyzing that data, it's possible to establish that the new black hole,
08:23from the merger of these two original black holes,
08:26weighs as much as something like 140 times the mass of our Sun.
08:31It's really difficult to overstate the importance of gravitational wave detection.
08:36It's like adding on an entirely new sense.
08:39All of a sudden, there's a brand new way to explore the rest of the universe.
08:47Invisible cosmic collisions are just the beginning of what gravitational wave astronomy can reveal to us.
08:55Now, scientists are using gravitational waves to revisit other long-standing mysteries.
09:01Like, what causes the brightest explosions in the cosmos?
09:08This is not an everyday car crash.
09:10This is the most dramatic event that you're ever going to see in our universe.
09:15Across the universe, strange bursts of light puzzle astronomers.
09:34For just a fraction of a second, they shine more than a trillion times brighter than the Sun.
09:40Then, they vanish.
09:44These brief flashes of light are known as gamma ray bursts, or GRBs for short.
09:51And they're such a mystery because they are insanely energetic, and we don't know what causes them.
09:58For decades, these short gamma ray bursts have been an enigma.
10:05No explanation was off limits, no matter how wild.
10:10Is it a supernova? Is it an alien civilization saying hello?
10:14You know, we just don't know.
10:15In August 2017, the Fermi Gamma Ray Telescope detected another short gamma ray burst.
10:26But this one was different.
10:29So, a gamma ray burst went off 130 million light years away.
10:34And it actually produced a ripple in space and time that LIGO could detect.
10:37Gravitational waves could help finally reveal what causes one of the brightest explosions in the universe.
10:48LIGO's data suggests the culprit could be two massive objects spiraling towards each other and colliding.
10:55But based on the gravitational wave data, these two objects were too small to be black holes.
11:04They had to be something else.
11:07Not black holes, but the ultra-dense cores of collapsed stars called neutron stars.
11:14A neutron star is what's left over after a massive star collapses in on itself.
11:22It's very, very dense because it took all essentially the mass of the core and contracted it into a really, really small radius.
11:37As the dense neutron stars spiral ever closer, the gravitational wave signal gets stronger and stronger.
11:45Until they collide, releasing an epic burst of gravitational waves.
11:53Because they're not black holes, light can get out.
11:58And if you smash two things together at these kind of absolutely massive speeds, there's a huge amount of energy involved.
12:05Energy we detected both as invisible gravitational waves and visible light.
12:15Could this light be a mysterious and ultra-powerful gamma ray burst?
12:22How could these colliding dead stars be associated with gamma ray bursts, which are in fact the most energetic explosions we see in the entire universe?
12:30Neutron stars have powerful magnetic fields that trap particles of gas and dust.
12:36During a collision, the swirling magnetic fields twist up, building up more and more energy.
12:44You have lots of little particles of matter that are trying to keep up with these rapidly spinning magnetic fields.
12:53That starts swooshing them round until they reach pretty much the speed of light.
13:00And eventually they're kind of shot out of the remnant in a tight beam.
13:04The beam is a gamma ray burst.
13:09But they're not always easy to detect.
13:12If the jet coming out is pointed right at you, then you see this extremely high energy event, the gamma ray burst.
13:20If it's not pointed at us, we might miss it.
13:27Fortunately, the gravitational waves show us where to look.
13:30Following the gamma ray burst, we spotted a strange red cloud, evidence of a heavy element factory.
13:45After the initial collision, there is a shell of debris moving outwards.
13:50But then, high energy neutrons come slamming into this material and start to build heavier elements one after another.
14:03We can see the gold.
14:06We can see the potassium.
14:09We can see the plutonium being created before our very eyes.
14:14The neutron star collision produced huge quantities of heavy elements, blasting out enough gold and platinum to weigh more than ten times the mass of the Earth, solving a long-standing mystery.
14:31We knew that supernova explosions did create some of the heavier elements.
14:36But from everything we've observed about supernovae, they don't happen often enough to really populate a galaxy with all of the heavier elements that we observe.
14:47This was the missing piece.
14:50The gold on your wedding ring, the gold in your jewelry, was formed and forged from a titanic collision before the Earth even existed.
15:01The combination of gravitational waves and telescopes proves that neutron star collisions create precious metals and cause super bright gamma ray bursts.
15:17When you can measure a gravitational wave signal and a light signal like a gamma ray burst, you get a whole new way to solve complicated, intertwined physical processes.
15:34It's like you're watching a symphony on mute, and then you hit that button and the sound comes on, and it's just a completely different picture.
15:41The sounds of the cosmos don't just reveal collisions.
15:53It turns out we can use gravitational waves to help us understand some of the biggest mysteries of the cosmos.
15:59Gravitational waves are a new way to listen to the universe, revealing unseen epic cosmic events and adding vital details to our picture of the cosmos.
16:24Every new way we figure out to probe the universe is a good thing, and detecting gravitational waves, it's a new dimension to being able to study the universe.
16:37It's like having a new sense.
16:39This new sense could be just what astronomers need to answer some of the biggest questions in physics.
16:44Like, what is the speed of gravity?
16:49And does it travel at the universe's speed limit?
16:54One of the things we learned early in science is that the universe has an absolute speed limit, which is the speed of light in a vacuum, which is 186,000 miles per second.
17:08Light from the sun takes 8 minutes and 20 seconds to reach Earth.
17:16So, if the sun disappeared, we wouldn't miss its light immediately.
17:22But how quickly would we notice its missing gravity?
17:25The first thing that we'd notice is nothing. Things would seem very normal. But then, they wouldn't.
17:36There would be nothing curving space where Earth is located, and so Earth would take off in a straight line, moving at the same speed at which it orbits the sun.
17:46And things will get cold and lonely really, really fast.
17:54According to Albert Einstein, our skies would go dark, and the Earth would be flung into deep space at exactly the same time.
18:03It's a foundation of his famous theory of relativity, still the most complete theory of how our universe works.
18:11Einstein's theory of relativity has been a fantastic theory. It explains so many things for us, including gravity.
18:20But, when we look out at the universe, there are many mysteries. There are things that are quite hard to explain.
18:29At the top of the list, the mystery of our expanding universe.
18:33There is something pushing outward that is making that expansion rate ever and ever faster.
18:43Astronomers call this something dark energy.
18:48It accounts for 70% of the total energy in the universe.
18:53Einstein's models of the universe need dark energy to work, but we have no idea what it is.
19:07Dark energy is not something we actually understand. It's kind of a placeholder term for something we don't understand.
19:14And so people naturally are looking for better theories. Theories that are a bit like Einstein's theory, but just go that bit further and explain some of these things that we don't currently understand.
19:28One way to excise dark energy is with a new theory of gravity.
19:33One where the speed of gravitational waves is different from the speed of light.
19:38There are some so-called non-Einsteinian theories for the structure of space-time itself that don't actually require dark energy.
19:47For example, if gravity doesn't propagate through space-time at the same speed that light does, you could find models that don't actually require dark energy.
19:57It could be a clean, simple, albeit very, very profound solution to this underlying problem.
20:02In order to overthrow Einstein and eliminate dark energy, the speeds of light and gravity must be different.
20:12We know the speed of light. So, how do we test the speed of gravity?
20:19In order to test the speed of gravity, you need to have a system that emits both gravitational waves and light.
20:26The colliding neutron stars detected by LIGO in 2017 are part of the solution.
20:36The collision released a flash of light along with a burst of gravitational waves.
20:45But the universe threw a curve ball.
20:48The light signal arrived 1.7 seconds after the gravitational wave signal.
20:56Does that mean gravitational waves travel slightly faster than light?
21:03Albert Einstein predicted that gravitational waves would move at the speed of light.
21:08So, what if Albert Einstein was wrong?
21:11I know, sounds crazy, right?
21:12That's like, almost as crazy as me being wrong, right?
21:15But, if Einstein was wrong, that's one thing, but a bigger problem is that we'd have to rethink our physics.
21:23Before we do that, let's take a closer look at the neutron star collision site.
21:31It's surrounded by a shroud of gas and dust.
21:34Light is made of particles called photons, which scatter when they hit obstacles.
21:42But gravitational waves pass through anything.
21:47They pass right through everything like it's not there.
21:51Light, on the other hand, was slowed down by interactions with that matter.
21:56It didn't just escape immediately like the gravitational wave signal did.
21:59The debris gave the gravitational waves a head start by slowing the light.
22:07So, gravitational waves and light do, in fact, travel at the same speed.
22:13Einstein was right.
22:15This one event ruled out the other theories of gravity that are competing with Einstein's theory.
22:22Things that people have been working on all their life, and overnight, it's gone.
22:27Thanks to gravitational waves, dark energy remains our best explanation for why the universe's expansion is accelerating.
22:38Maybe dark energy isn't what we think it is.
22:42And maybe tomorrow, or maybe next year, or maybe next decade, or next century, we will discover that.
22:47Gravitational waves are a huge step forward in our effort to understand the universe.
22:52And I mean everything. Space, time, matter, dark energy.
22:58We have a completely new universe to view now.
23:03Now, astronomers want to use gravitational waves to answer another mystery.
23:08What happens when supermassive black holes collide?
23:15We first detected gravitational waves in 2015.
23:29Since then, they've revealed colliding black holes across the universe.
23:39Prior to LIGO going online, we never witnessed black hole collisions directly.
23:45But now that we can witness them with our observatories, we're finding them pretty regularly.
23:49We're seeing gravitational waves come across the LIGO experiment left and right.
23:57But LIGO has only been listening for gravitational waves from black holes on the smaller end of the cosmic scale.
24:04When we look at the cosmic zoo of black holes out there, we find small ones weighing, you know, ten, maybe thirty times as much as the sun.
24:16And then large all the way up to extra large going from like a million to a billion times as much as the sun.
24:21These supermassive black holes lurk at the hearts of galaxies.
24:28When galaxies merge, supermassive black holes should merge too.
24:37But even though we see galaxies colliding across the universe, we've never seen two supermassive black holes collide.
24:46Because they have too much orbital energy to get close enough to merge.
24:57That orbital energy has to go somewhere.
25:01And what supermassive black holes do is they throw out stars that are around the core of the galaxy.
25:07But when they get sufficiently close, there are just no more stars to throw out.
25:12And so the idea is they can't merge.
25:14So there's a problem. How is it that they manage to bridge that gap and finally spiral in?
25:21The only way to understand if supermassive black holes merge is by looking at their gravitational wave signal.
25:29Two supermassive black holes merging should release a burst of gravitational waves millions of times more powerful than a stellar mass black hole merger.
25:38But LIGO won't hear a thing.
25:42The problem with using LIGO to detect the merger of supermassive black holes is actually a scale of time.
25:51One wave, as these things move around each other very slowly, would take over ten years to go by. Just one wave.
25:56In order to detect a gravitational wave with periods of decades, you also need an experiment that can be extremely stable over that amount of time.
26:10Vibrations from earthquakes, weather, or even nearby traffic prevent LIGO from listening for a decade just to hear one wave.
26:23But there may be another way to detect gravitational waves from supermassive black holes using a strange type of dead star called a pulsar.
26:35A pulsar is a kind of neutron star that is rapidly spinning and has a beam of radiation that makes wide circles across the sky.
26:49And when that flash of circle washes over the planet Earth, we get a little beep, a little beep.
26:56We get pulses of radiation, hence pulsar.
26:58Pulsars are the best time keepers in the universe.
27:04But passing gravitational waves make them miss a beat.
27:09What if we noticed that the frequency of a pulsar was shifting very, very slowly, year to year to year, over ten years or more,
27:18just slightly getting a little bit longer as space itself was changing between us and the pulsar.
27:23By monitoring dozens of pulsars, Chiara Mingarelli and a team of astronomers have created a galaxy-sized gravitational wave detector.
27:36It's called a pulsar timing array.
27:40You can really look for deviations in those arrival times over decades, almost like a tsunami warning system to show you when a gravitational wave is passing by.
27:56After 12 years, the team detected the same change in a number of pulsars.
28:01These pulsars are all thousands of light years apart.
28:07If you think about it, it's difficult to make a signal that's the same in all of these pulsars.
28:13This has to be this common signal from something like a gravitational wave event.
28:18The signal the team detected wasn't created by just two supermassive black holes colliding.
28:29It's evidence of gravitational waves from hundreds of pairs of supermassive black holes, all in different stages of merging.
28:38Because it takes so long for one of these individual binary systems to merge, there could be thousands, if not millions, of these signals all being emitted at the same time.
28:54All of them. They all create this gravitational wave background that we're just starting to see the first signs of now.
28:59Astronomers predict this gravitational wave background fills our universe.
29:10If the signal the team detected is confirmed, it's proof that supermassive black holes do merge.
29:18The next step is to observe that as it happens.
29:23It would be a dream to see two supermassive black holes merging, emitting gravitational waves.
29:28And also being able to point a telescope at them and to see the physics of how they merge.
29:34Gravitational waves reveal the hidden workings of the cosmos.
29:39They reach the farthest corners of our universe.
29:44Now, astronomers are using gravitational waves to look back in time.
29:50They'll let us see all the way back to the earliest moments of our Big Bang.
29:55Earth-1.
30:173.8 billion years ago, the universe sparks into life.
30:25The tiny speck of energy expands and cools.
30:29The infant cosmos is a fog of tiny particles of matter.
30:35Over time, the particles form atoms of hydrogen and helium.
30:41The fog clears and the first light races across the universe.
30:46We call that light the cosmic microwave background.
30:51The cosmic microwave background is simply the most distant light we can see.
30:55So looking at it gives us baby pictures of our universe the way it looked 400,000 years
31:00after a big bang.
31:03What happened before these baby pictures remains a mystery.
31:08The leading theory is that in the very first second of the big bang, our infant universe
31:15had a growth spurt.
31:19Scientists call this idea inflation.
31:23In a billionth of a billionth of a billionth of a second, our universe grew a billion billion
31:30billion billion billion billion billion times bigger.
31:34That is the mother of all growth spurts.
31:37It laid the foundations for the entire cosmos that we know today.
31:50Inflation is just a theory.
31:52But there may be a way to prove it happened.
31:56Scientists think that during that brief moment of cosmic expansion, inflation stretched tiny
32:01fluctuations of gravity.
32:04That is such a violent process that it actually causes ripples and distortions in the very
32:08shape and fabric of space itself, which we can see today as gravitational waves.
32:16Scientists call these theoretical ripples through the early universe primordial gravitational waves.
32:21When they were first released, these were deafening.
32:28But in the billions of years since, our universe has grown bigger and colder and these gravitational
32:34waves have diluted so that they barely even exist today.
32:41Scientists searched for signs of these very weak primordial gravitational waves in the cosmic
32:46microwave background.
32:50And in 2014, a team using their purpose-built microwave array in Antarctica called BICEP found
32:58a strange swirling pattern.
33:01When they saw those swirls, they saw those patterns.
33:04They thought they had seen the signature of primordial gravitational waves.
33:09Now, this is really the conclusive evidence that inflation had to have happened.
33:17The results were exciting, but there was a glitch.
33:22This amazement lasted for a few months until the crack started to appear in this, and gradually
33:29it all collapsed.
33:33The signal thought to be proof of primordial gravitational waves and the theory of inflation turned out
33:40to be a case of mistaken identity.
33:46As this light from the ancient universe, from the cosmic microwave background, travels through
33:51the universe, it had to travel through dust before reaching our detectors.
33:55And the dust itself can affect the light and mimic what the primordial gravitational waves can do.
34:06The primordial gravitational wave signal turned out to be mainly clouds of dust floating
34:12through space.
34:16That's how BICEP bit the dust.
34:20Failed to detect primordial gravitational waves.
34:25Can LIGO do any better?
34:29Unfortunately, LIGO can't help us in observing primordial gravitational waves.
34:34It can't even observe supermassive black holes at the centers of galaxies.
34:38It is designed to observe in a particular frequency range.
34:41Primordial gravitational waves are at such a low frequency, in such a low amplitude, that
34:49there is no hope of LIGO being able to detect them.
34:56But scientists hope that an ambitious project called LISA will.
35:03Not on Earth, but from 30 million miles above.
35:08LISA is like LIGO, but bigger and in space.
35:16LISA, or the Laser Interferometer Space Antenna, will be a system of three satellites arranged
35:25in a giant triangular formation, 1.5 million miles apart.
35:29If a gravitational wave passes through them and changes that distance, they can detect that.
35:35Because the satellites are so much farther apart, a very low frequency wave can make
35:40a detectable change.
35:41LIGO wouldn't be able to see that, but LISA could.
35:46As well as listening for low frequency gravitational wave sources like supermassive black hole mergers,
35:52LISA will listen for primordial gravitational waves from the dawn of time.
35:58If it detects them, we will know that the infant universe inflated.
36:05Inflation has explained almost everything we measure in modern cosmology.
36:11It's an incredibly successful theory.
36:13The icing on the cake would be if we could also discover these gravitational waves that it's
36:19supposed to have created.
36:21From the Big Bang to the most massive black holes, the universe talks to us using gravitational
36:30waves.
36:31LISA just like with telescopes, we're using gravitational waves to look at different types of objects,
36:40neutron star mergers and black hole mergers, and learn more about the universe around us.
36:47They could even reveal the most elusive substance in the universe, dark matter.
36:56If anything is going to help us understand the nature of dark matter, it might just be gravitational
37:01waves.
37:11Across the universe, an invisible substance holds galaxies together.
37:17Without it, they would fly apart.
37:22The Milky Way should have dispersed long ago.
37:24And the Magellanic clouds right in front of us are exactly the same.
37:28These things should be just shedding stars left and right as they fly off this rotating galaxy.
37:32Instead, they're not.
37:33They're holding together.
37:35There are motions in the stars that we just cannot account for unless there's something
37:39holding the whole thing together.
37:43We call this mysterious substance dark matter.
37:47It doesn't interact with light, so we can't see it.
37:51But we cannot ignore it.
37:55From the motions of stars inside of galaxies, to the motions of galaxies inside clusters, to
38:01the very structure of the universe itself, we see evidence for dark matter everywhere we
38:08look.
38:12We think dark matter makes up 85% of the matter in the universe.
38:20But because we can't see dark matter with telescopes, we know very little about it.
38:25While we know that it's there, we haven't actually answered the question of what it is or how
38:33it interacts or why it's there or how it's created.
38:36So you have to be really creative if you want to go after this stuff and really understand
38:41what's it made out of.
38:46One creative theory suggests that black holes make up dark matter.
38:52Not the regular stellar mass black holes that LIGO detects, or the supermassive black holes
38:58that lurk at the center of galaxies, but tiny primordial black holes born during the period
39:05of rapid expansion in the first moments of the Big Bang.
39:12Primordial black holes could be potential explanations for what we call dark matter.
39:17And if there's enough of them, they can hold an entire galaxy together.
39:22We don't know if primordial black holes exist, but gravitational waves could change that.
39:31When you form a primordial black hole, you send out a burst of gravitational waves that
39:36in principle carries on traveling through the universe and you might be able to detect it
39:40still today.
39:41The problem is that these things would have emitted gravitational waves at a frequency
39:46that is not detectable by LIGO.
39:48And so it's very hard to discern whether or not they are plentiful enough to actually serve
39:54as a compelling dark matter candidate.
39:58If primordial black holes do exist, they still might not explain all the dark matter in the
40:04universe.
40:06They might be working with another type of dark matter to hold galaxies together.
40:12The upcoming LISA mission may fill in the blanks.
40:17What we call dark matter could be simple.
40:19It could just be made of one thing that absolutely floods the universe.
40:24Or it could be made of many different things that all work together to combine to make this
40:29effect.
40:30Is dark matter all primordial black holes?
40:33Is it something else that we haven't thought of yet?
40:36Gravitational waves could provide those answers.
40:41The detection of tiny gravitational waves generated by primordial black holes will be
40:46a huge advance in our understanding of dark matter.
40:50With gravitational wave astronomy, we're seeing things that we have never seen before.
40:56So who knows what we're going to see as we continue to look out into space.
41:00We've been able to see dozens of black holes merge, two neutron stars merging, and discovered
41:09from that merger that neutron stars can make platinum and gold.
41:16From thinking that we would never be able to see gravitational waves to seeing gravitational
41:22wave signals happen on the regular.
41:25It's just crazy.
41:27We've already heard epic explosions.
41:31We've identified the brightest lights in the cosmos.
41:35And we have solved some of the biggest mysteries in astronomy.
41:43But that is just the beginning.
41:47Right now is a golden age in astronomy.
41:49Think of the time that you're living in.
41:51The first detection of gravitational waves by LIGO was only a couple of years ago.
41:56You were here at the birth of this entirely new view of the universe.
41:59So how is this all CreateCorp?
42:04You're welcome.
42:08That's true.
42:10Here is the release the solar waves.
42:16You've already described what we've helped us toánh breathe.
42:17From the space to the star having internationally, you can see SLIAM mise, which means a really