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	2022-12-08: How Are Quasiparticles Different From Particles? 05:47: In fact sound waves in solids do propagate exactly like this. 13:28: ... appear in lattices of quantum spin, like are magnons - quanta of waves in that lattice, or skyrmions, which are localized, stable topological ...
	2022-11-23: How To See Black Holes By Catching Neutrinos 00:30: There’s the James Webb Space Telescope and its infrared supervision and of course LIGO with its ability to see gravitational waves. 04:32: ... expanding EM waves created by the charged particle expand slower than the particle itself, ...
	2022-11-09: What If Humanity Is Among The First Spacefaring Civilizations? 18:34: They imagined waves traveling from both cause to effect and from effect to cause. 18:50: ... with the time-reversed signals corresponding to negative frequency waves. ... 18:34: They imagined waves traveling from both cause to effect and from effect to cause.
	2022-07-27: How Many States Of Matter Are There? 10:24: The frequent interactions between people cause liquid-like phenomena like currents and waves as individuals lose their autonomy of motion.
	2022-05-25: The Evolution of the Modern Milky Way Galaxy 03:22: ... disks, and their violent convulsions settled into  the density waves that we see as spiral arms. The   new spiral galaxies ... 12:11: ... formation in about  2 billion years. The accompanying supernova waves   may not be the best thing for life on Earth, but  we do have 2 ...
	2022-05-18: What If the Galactic Habitable Zone LIMITS Intelligent Life? 08:01: ... bulge. As the galactic bulge grew,   it was wracked by further waves of supernovae. As  Moiya mentioned, having excessive exploding ...
	2022-03-08: Is the Proxima System Our Best Hope For Another Earth? 18:33: When those cosmic strings radiate gravitational waves, how is the Higgs field supposed to smooth itself out?
	2022-02-23: Are Cosmic Strings Cracks in the Universe? 10:09: ... in the kinks causes them to radiate   gravitational waves. In this way cosmic strings  shed energy, and so they slowly decay ... 12:19: ... “regular” cosmic strings in many ways -  like the gravitational waves and the lensing.   But there are differences. While cosmic ...
	2022-02-16: Is The Wave Function The Building Block of Reality? 14:52: ... BuzzBen asks what happens when gravitational waves pass through black holes. Is there gravitational lensing? Well that’s ...
	2022-01-27: How Does Gravity Escape A Black Hole? 02:02: For example we have gravitational waves - ripples in spacetime caused by certain types of motion. 02:08: ... at the speed of light, and that’s been confirmed when gravitational waves from colliding neutron stars reach us at about the same time the ... 02:46: It would take 8 minutes for the Sun’s deep indentation in the fabric of space to smooth itself - in the wake of some pretty crazy gravitational waves. 02:02: For example we have gravitational waves - ripples in spacetime caused by certain types of motion.
	2022-01-19: How To Build The Universe in a Computer 00:30: ... spiral structure will be obliterated, gas will be compacted to produce waves of supernovae, and the giant Milkdromeda galaxy will have been ... 10:02: ... watch as galaxies form, with gas and dark matter interacting to produce waves of star formation and supernovae, settling into spiral structures - just ...
	2021-12-20: What Happens If A Black Hole Hits Earth? 09:03: ... seismic waves would reach all points on the Earth’s surface. Even at the lowest mass ... 17:55: ... string theory. There are simulations that suggest that the gravitational waves created when fuzzball merge should look almost exactly the same as those ... 18:16: ... may be that the so-called ring-down - the waves produced as the merged object settles back into a spheroid - lasts ... 17:55: ... string theory. There are simulations that suggest that the gravitational waves created when fuzzball merge should look almost exactly the same as those ... 18:16: ... may be that the so-called ring-down - the waves produced as the merged object settles back into a spheroid - lasts longer for ...
	2021-11-10: What If Our Understanding of Gravity Is Wrong? 09:15: AQuaL also had the unfortunate prediction of faster-than-light waves in this added scalar field, which broke causality.
	2021-09-15: Neutron Stars: The Most Extreme Objects in the Universe 10:06: ... making a very weak gravitational wave  signal. These gravitational waves are   much weaker than the signals we’ve detected when ...
	2021-09-07: First Detection of Light from Behind a Black Hole 05:29: ... we’ve all experienced this Doppler shift when the sound waves of an ambulance siren shift between higher and lower pitch as it passes ...
	2021-08-10: How to Communicate Across the Quantum Multiverse 00:23: ... your skull, that sound is nothing but an expanding series of density waves - air molecules mindlessly bumping and shoving each other, oblivious to ... 00:53: ... traffic. Each sound is its own configuration of overlapping sinusoidal waves. All these waves overlap to produce a fantastically complex bath of ... 01:46: ... brain filtered out all the others. The presence of those other sound waves has no impact on how my voice ... 02:29: ... pilot wave theory, which says that particles are particles and waves are waves - and the wavefunction’s job is to shuttle actual real ... 04:30: ... understand all of this, let’s first go back to sound waves. As we discussed in that previous episode, this ability for waves to pass ... 06:09: ... by too much. Non-linearities creep in which can do things like damp the waves - cause them to lose ... 00:23: ... your skull, that sound is nothing but an expanding series of density waves - air molecules mindlessly bumping and shoving each other, oblivious to ... 02:29: ... pilot wave theory, which says that particles are particles and waves are waves - and the wavefunction’s job is to shuttle actual real particles around - ... 06:09: ... by too much. Non-linearities creep in which can do things like damp the waves - cause them to lose ... 00:23: ... your skull, that sound is nothing but an expanding series of density waves - air molecules mindlessly bumping and shoving each other, oblivious to the ... 00:53: ... is its own configuration of overlapping sinusoidal waves. All these waves overlap to produce a fantastically complex bath of density fluctuations. A ...
	2021-08-03: How An Extreme New Star Could Change All Cosmology 09:18: ... with black holes and neutron stars when LIGO detected the gravitational waves from the last moment of those inspirals. But it should happen with white ...
	2021-07-21: How Magnetism Shapes The Universe 07:15: When radio waves interact with those electrons, their polarizations are also affected.
	2021-07-13: Where Are The Worlds In Many Worlds? 01:47: ... wave mechanics, this principle tells us that when two waves overlap, their amplitude - in this case the height of the ripple - is ... 02:25: The weirdness of this is clearer if we watch two waves cross each other in one dimension. 02:30: ... at their collision seems to hold no record of the shapes of the incoming waves, and yet its motion perfectly regenerates those waves, which travel on as ... 02:46: If the amplitude of the waves is is too high, the principle can break down. 03:06: The main point is that this holds approximately for familiar waves, up to some amplitude. 03:13: But the superposition principle seems to always hold for the waves that drive quantum mechanics. 03:39: Quantum mechanics is a theory about waves. 02:25: The weirdness of this is clearer if we watch two waves cross each other in one dimension. 01:47: ... wave mechanics, this principle tells us that when two waves overlap, their amplitude - in this case the height of the ripple - is the sum of ...
	2021-06-09: Are We Running Out of Space Above Earth? 00:00: ... of the Chinese Long March 5 rocket burning up on re-entry has made waves through the world- in some cases, quite literally, as the debris from ...
	2021-05-25: What If (Tiny) Black Holes Are Everywhere? 03:08: ... such black holes the Hawking radiation is just photons - electromagnetic waves with kilometers-long wavelengths, so really, really low energy radio ... 11:17: ... with the limits of the uncertainty principle in detecting gravitational waves. ...
	2021-05-19: Breaking The Heisenberg Uncertainty Principle 00:25: ... And also pretty recently we have the measurement of gravitational waves by ... 02:13: ... you can watch our episode on how it comes about from thinking about waves. ... 05:19: For fainter gravitational waves we quickly run up against the Heisenberg limit. 05:36: ... paths and then later recombined in such a way that the electromagnetic waves of these laser beams destructively ... 06:05: This measurement is incredibly sensitive to the path lengths - but that means it’s also sensitive to the phase of the light waves. 06:11: Phase refers to the relative positions of the peaks and troughs of the waves. 07:07: To improve our ability to detect faint gravitational waves we need to reduce the uncertainty in the phase of the laser beams. 07:15: That would enable us to line up those waves more perfectly to reduce quantum fluctuations. 09:05: Less flickering due to random phase shifts means that we can see real signals due to much weaker gravitational waves. 09:43: But that noise is less of a problem than the phase uncertainty, at least for the higher frequency gravitational waves.
	2021-04-21: The NEW Warp Drive Possibilities 12:47: And possibly also building a starship, to propel humanity into the galaxy on waves of warped space time.
	2021-03-23: Zeno's Paradox & The Quantum Zeno Effect 14:45: Max Graham asks how gravitational waves encode the distance that they've traveled. 15:08: But it's different with gravitational waves from merging black holes. 15:11: The intensity or amplitude of those waves drops off with distance, not distance squared. 15:32: But that chirp mass also determines the power that was radiated in gravitational waves during the inspiral. 15:11: The intensity or amplitude of those waves drops off with distance, not distance squared. 14:45: Max Graham asks how gravitational waves encode the distance that they've traveled.
	2021-03-16: The NEW Crisis in Cosmology 11:57: ... before too long we may even be able to use gravitational waves from merging black holes   to measure the Hubble constant. ... 15:19: ... the professor says that you just add   up the ripples of three waves. The student trolls the teacher with "what about four slits" which ... 11:57: ... merging black holes   to measure the Hubble constant. These waves get stretched by the expanding universe, just like   light does. But unlike ... 15:19: ... slits" which they reply with "obviously you add up the ripples of four waves" And then "what about 5 slits" etc.. until finally   "what about ... 10:08: ... “baryon acoustic oscillations”  are the fossils of ancient sound waves   that reverberated through the hot, dense plasma of the early ... 15:19: ... you can figure out the interference pattern by thinking of circular waves   originating from the slits, and calculating how these ripples add ...
	2021-03-09: How Does Gravity Affect Light? 07:40: The idea is that any wave can be described as an infinite number of point-like oscillations, each of which produces new waves. 07:49: The sum of all those waves perfectly describes the future evolution of the original wave.
	2021-02-24: Does Time Cause Gravity? 08:39: Last time we talked about the gravitational wave background - the ambient buzz of gravitational waves from the distant and ancient universe. 10:04: ... the big bang, and gravitational Kinkusnacht asks whether gravitational waves can be used to test ideas in quantum ... 10:21: The most well known prospect is by detecting the signatures of primordial gravitational waves - waves from the inflationary epoch. 10:35: ... of those waves with matter right after inflation may have caused characteristic ... 10:21: The most well known prospect is by detecting the signatures of primordial gravitational waves - waves from the inflationary epoch.
	2021-02-17: Gravitational Wave Background Discovered? 00:00: ... impressive when we built this giant machine that spotted gravitational waves from colliding black holes well we've just taken it to the next level ...
	2021-01-19: Can We Break the Universe? 00:02: Black holes, gravitational waves, he was even the first to realize that friggin lasers could be a thing.
	2021-01-12: What Happens During a Quantum Jump? 04:45: He believed it all came down to waves—and that nothing was particularly special about these waves compared to any other kind of classical wave.
	2020-11-04: Electroweak Theory and the Origin of the Fundamental Forces 05:07: Like all waves, the wavefunction has a phase - the current position of the peaks and troughs.
	2020-09-21: Could Life Evolve Inside Stars? 14:01: ... any continuous, periodic function can be represented as a sum of sine waves of different ... 14:11: But then motion in a circle can be represented by 2 separate sine waves for displacement in the x-y directions.
	2020-09-08: The Truth About Beauty in Physics 09:30: And Maxwell’s equations, which parsimoniously unite electricity and magnetism but also predict the existence of electromagnetic waves - of light. 09:42: ... mirrors - but the resulting theory predicts black holes, gravitational waves, and even the big ... 09:30: And Maxwell’s equations, which parsimoniously unite electricity and magnetism but also predict the existence of electromagnetic waves - of light.
	2020-08-17: How Stars Destroy Each Other 10:43: ... to our episode on this strange new observation by LIGO: gravitational waves from the merger of a black hole with ... something ... 13:15: That's an easy one - in order to generate detectible gravitational waves, both objects need to be extremely compact. 13:22: The waves get generated when extreme masses spiral together at very small distances. 13:32: They are ripped apart before getting close enough to generate gravitational waves.
	2020-08-10: Theory of Everything Controversies: Livestream 00:00: ... between being at the beach and not being exactly sure where the waves are versus being at the beach and not being sure where the pacific ...
	2020-07-28: What is a Theory of Everything: Livestream 00:00: ... of this theory from 100 years ago was this notion of gravitational waves and these were only verified experimentally just a few years ago so ...
	2020-06-30: Dissolving an Event Horizon 08:55: ... any rate, our observations of gravitational waves from colliding black holes and various other methods for estimate black ... 15:14: ... mentioned that in conformal cyclic cosmology, photons and gravitational waves can pass the boundary from universe end to new big bang, and so there ...
	2020-06-22: Building Black Holes in a Lab 00:16: ... into tiny spaces in quasars or X-ray binary systems. Gravitational waves that perfectly match our theoretical prediction for black hole mergers. ... 02:12: ... So what happens if another fish goes over the waterfall? Since sound waves are just vibrations propagating through a medium, if the medium is ... 04:45: ... of water decreases, the current accelerates while the speed of surface waves slows ... 04:55: At some point the flow is faster than the waves - and that’s your analog event horizon. 05:01: ... the flow is in the opposite direction to the waves this is actually an analog white hole. Other experiments use a ... 08:04: ... black holes can donate some of their rotational energy to particles or waves that pass close by. This is the Penrose process, and when the particle ... 08:58: ... to great precision. On one side of the tank, a wave generator propagates waves across the surface where they pass across the ... 09:09: These waves are analogous to incoming particles. The waves are only 1 millimeter high, but superradiance can increase their height by as much as 10%. 04:55: At some point the flow is faster than the waves - and that’s your analog event horizon. 04:45: ... of water decreases, the current accelerates while the speed of surface waves slows ...
	2020-06-15: What Happens After the Universe Ends? 14:02: It turns out that, as well as photons, gravitational waves should be able to pass between aeons.
	2020-05-11: How Luminiferous Aether Led to Relativity 03:25: ... while the segments themselves just oscillate in place. In sound waves, air molecules oscillate back and forth to propagate a pattern in the ... 04:06: ... own corpuscular theory of light - light as tiny particles rather than waves. ... 05:08: ... an interference pattern passing between a pair of slits, like water waves do. These bright bands are points on the screen where the waveforms of ... 05:53: ... that in the 1860s, Maxwell’s equations predicted that electromagnetic waves should travel at exactly the speed of … wait for it, light. It was ... 06:48: ... classical waves travel at a constant speed relative to their medium. For example, sound ... 07:00: But hop in a jet plane and you can chase your own sound waves so they appear to stand still. 09:02: ... And this is exactly the method that LIGO uses to detect gravitational waves. ... 03:25: ... and forth to propagate a pattern in the density of the air. All familiar waves - what we’ll call classical waves - are a chain reaction that propagates ... 06:48: ... classical waves travel at a constant speed relative to their medium. For example, sound waves ...
	2020-04-28: Space Time Livestream: Ask Matt Anything 00:00: ... of photons that are redshifted okay and the restrict of gravitational waves what happens to their energy well so the answer is there are a couple ...
	2020-04-14: Was the Milky Way a Quasar? 07:25: ... shock waves created by the supernovae from a starburst in the Milky Way could ...
	2020-03-24: How Black Holes Spin Space Time 01:01: ... told us that black holes are very real. We’ve seen the gravitational waves caused by their mergers, we’ve witnessed the havoc they wreak on their ...
	2020-02-24: How Decoherence Splits The Quantum Multiverse 03:11: ... general wave mechanics, we say that a set of waves are coherent if they match in frequency and if the shape of the waves ... 04:36: In this case that mostly means these two paths - these wavefunction slices, which we can represent with simple sine waves. 04:44: ... the peaks of one wave line up with the peaks of the other - the two waves are perfectly in phase with each ...
	2020-01-27: Hacking the Nature of Reality 14:57: Well, the answer is that those waves would be affected - but not by much. 15:01: ... to merge faster, so that should increase the frequency of the those waves and to a lesser extend the actual shape of the ...
	2020-01-13: How To Capture Black Holes 00:24: ... new way we discover new things. When we figured out how to see in radio waves quasars and supernova remnants lit up the sky, When we learned to see in ... 00:59: ... not so surprising. Einstein’s general relativity predicted gravitational waves and astrophysics predicted black hole mergers. When two very massive ... 08:50: ... could lead to a bright burst of light to accompany the gravitational waves. ... 09:53: ... the release of gravitational waves delivers a kick to the final black hole - a bit like the recoil of a ... 00:59: ... holes whip the fabric of space into expanding ripples - gravitational waves - which saps orbital energy from the system. The black holes spiral closer ... 09:53: ... may be visible to telescopes on Earth right after the gravitational waves arrive. ... 00:59: ... they coalesce into a single black hole, and the powerful gravitational waves produced in the last fraction of a second are what LIGO detects - sometimes from ... 00:24: ... new way we discover new things. When we figured out how to see in radio waves quasars and supernova remnants lit up the sky, When we learned to see in ...
	2019-12-02: Is The Universe Finite? 01:25: ... episode how that speckled pattern is the frozen imprint of sound waves that reverberated through the first few hundred thousand years after the ...
	2019-10-15: Loop Quantum Gravity Explained 12:41: ... high-energy gamma rays travelling a wee bit slower than low energy radio waves due to the way they propagate through the graininess of a loop quantum ... 14:15: David Bennack likes the idea of gravitational lensing of gravitational waves. Well so do I, David. 15:03: Gravitational waves should be lensed in the same way as light, so it's a plausible explanation. 16:16: ... if the fabric of space and time can be stretched and if can have waves, that means it must have a sort of elasticity and resistance to ...
	2019-10-07: Black Hole Harmonics 00:14: And the rich harmonics of those vibrations, seen through gravitational waves, could hold the secrets to the nature of the fabric of spacetime itself. 02:14: ... inspiralling black holes make powerful spacetime ripples – gravitational waves – which intensify as the black holes approach merger, only becoming ... 02:48: As those vibrations give up their energy – in this case to sound waves – the vibrations fade. The bell rings down. 03:12: In the latter cases we can describe a vibrating string as a series of standing sine waves of different frequencies, all happening at the same time. 03:56: In the case of the event horizon, or any spherical-ish surface, we break down the oscillations not into sine waves but into spherical harmonics. 04:24: For a black hole, another way to think of its quasinormal modes is as a set of gravitational waves trapped in orbit around the black hole. 07:41: So this sort of frequency analysis of gravitational waves is being called gravitational wave spectroscopy. 12:41: So, long story short – the initial promise of LIGO and the first detection of gravitational waves really seems to be panning out. 04:24: For a black hole, another way to think of its quasinormal modes is as a set of gravitational waves trapped in orbit around the black hole.
	2019-06-20: The Quasar from The Beginning of Time 07:43: Look out for Physics Girl's exploration of gravitational waves at LIGO.
	2019-05-01: The Real Science of the EHT Black Hole 01:53: We can think of light from a very distant point as coming in a series or plane waves.
	2019-02-20: Secrets of the Cosmic Microwave Background 01:34: ... of matter right after the big bang which evolved as colossal sound waves reverberated through the first few hundred thousand years of the ... 02:05: ... single expanding shell of plasma is simplistic In reality these acoustic waves pulse in and out of their over-dense regions They oscillated And the ... 01:34: ... of matter right after the big bang which evolved as colossal sound waves reverberated through the first few hundred thousand years of the Universe's ...
	2019-02-07: Sound Waves from the Beginning of Time 01:22: They are the fossils of the first sound waves in the universe, imprinted on the distribution of galaxies on the sky. 02:54: Second: Light was able to exert an enormous pressure on this plasma, as we'll see that it'd lead to the production of colossal sound waves. 03:04: And third: Those sound waves travelled fast. 07:40: In reality, the density waves sloshed inwards and outwards. 12:39: I mean think about it. There are rings in the sky inscribed in galaxies, frozen echoes of the very first sound waves to reverberate across space-time. 07:40: In reality, the density waves sloshed inwards and outwards. 03:04: And third: Those sound waves travelled fast.
	2019-01-24: The Crisis in Cosmology 08:16: ...really vast sound waves that rippled across the universe. 12:37: Independent methods, like using gravitational lensing, or gravitational waves,...
	2018-12-20: Why String Theory is Wrong 08:17: These strings are vibrating with standing waves like guitar strings, and their energy also depends on the frequency of that vibration.
	2018-11-14: Supersymmetric Particle Found? 14:54: Some of you recalled a recent episode in which we talked about a study of gravitational waves that appears to refute the idea of extra dimensions.
	2018-11-07: Why String Theory is Right 00:59: ... string theory are literal strands and loops that vibrate with standing waves simply by changing the vibrational mode and you get different particles ...
	2018-10-18: What are the Strings in String Theory? 05:35: The key is that strings can carry waves. 05:48: Roughly speaking, when these traveling waves overlap each other, they can either stack up or cancel out, constructive or destructive interference. 06:48: Niels Bohr came up with the first quantum model for electron orbits by thinking of them as ring-like standing waves around the hydrogen atom. 08:00: By the way, those vibrations, the standing waves, are not some abstract internal wave. 08:05: The strings are real physical strands, and the waves are wiggles in actual space. 05:48: Roughly speaking, when these traveling waves overlap each other, they can either stack up or cancel out, constructive or destructive interference.
	2018-10-10: Computing a Universe Simulation 12:07: ... week, we looked at an amazing new result in which gravitational waves were used to search for and rule out the existence of an extra spatial ... 12:21: Glenn Stern asks about the fact that the gravitational waves from this neutron star merger arrived two seconds before the light from the merger. 12:31: How then can we say that the gravitational waves and the light traveled at the same speed? 12:40: Those gravitational waves and that light traveled a crazy long distance, 40 megaparsecs or around 150 million light years. 13:10: That led to the radio emission arriving hours after the gravitational waves. 13:41: The gravitational waves start to get strong before the neutron stars even make contact.
	2018-10-03: How to Detect Extra Dimensions 00:10: Fortunately, with the discovery of gravitational waves, we're now living in a science fiction future. 01:29: The resulting kilonova is first observed in gravitational waves and then as a gamma ray burst. 01:35: In GW170817, the flash of gamma radiation arrived 1.7 seconds after the gravitational waves. 01:50: Among other things, this optical identification gave a completely independent measurement of the distance traveled by the gravitational waves. 08:37: Well, here's where we finally get back to our gravitational waves. 08:41: ... into this hypothetical extra spatial dimension, then gravitational waves should lose energy to that extra dimension as they travel through ... 09:02: In regular 3D space, gravitational waves drop in intensity proportional to just distance, not distance squared. 09:11: If space has four or more dimensions, then gravitational waves should drop off in intensity faster than you'd expect in three dimensions. 10:20: ... super convenient property of gravitational waves is that you can figure this out by looking at other properties of the ... 09:02: In regular 3D space, gravitational waves drop in intensity proportional to just distance, not distance squared.
	2018-09-20: Quantum Gravity and the Hardest Problem in Physics 02:25: It describes particles as waves of infinite possibility whose observed properties are intrinsically uncertain. 02:41: That math started with the Schrodinger equation, which tracks these probability waves through space and time. 13:30: When two black holes merge, a lot of energy is pumped into gravitational waves.
	2018-09-05: The Black Hole Entropy Enigma 00:53: Also, we've seen them in their gravitational effects on their surrounding space and in the gravitational waves caused when they merge. 06:22: If you merge two black holes, some of their mass gets converted to the energy radiated away in gravitational waves. 00:53: Also, we've seen them in their gravitational effects on their surrounding space and in the gravitational waves caused when they merge.
	2018-08-30: Is There Life on Mars? 11:51: This is the same way we map the ocean, by analyzing radio waves reflected from layers below the surface.
	2018-08-15: Quantum Theory's Most Incredible Prediction 15:13: Another possible mechanism is through turbulence in waves generated by the rapid motion of magnetic fields.
	2018-08-01: How Close To The Sun Can Humanity Get? 04:08: Finally, it will detect radio waves from processes responsible for the acceleration of particles in the solar wind.
	2018-07-11: Quantum Invariance & The Origin of The Standard Model 04:03: Phase is just the wave's current state in its up-down oscillation. 04:07: When we apply the Born rule, what we're doing is squaring these two waves and adding them together. 04:03: Phase is just the wave's current state in its up-down oscillation.
	2018-04-25: Black Hole Swarms 08:05: ... know that, if we want to understand the source of these gravitational waves. ... 09:17: Last week, we talked about some of the incredible ways for detecting gravitational waves beyond LIGO. 09:26: Majestic potato asked, whether a supernova can produce gravitational waves detectable from Earth? 09:40: Gravitational waves are produced when the quadrupole moment of a mass distribution changes. 09:52: So if the explosion of a supernova is concentrated, say, more on one side, then LIGO could potentially see the resulting gravitational waves. 10:00: Juxtaposed stars asks whether, theoretically, you could build an engine to extract power from gravitational waves via the sticky bead method? 10:29: A couple of you asked whether the gravitational waves interfere with each other? 10:38: Two gravitational waves crossing paths will add together at any one point in space and time. 10:55: You'd need a material capable of blocking gravitational waves. 10:38: Two gravitational waves crossing paths will add together at any one point in space and time. 09:26: Majestic potato asked, whether a supernova can produce gravitational waves detectable from Earth? 10:29: A couple of you asked whether the gravitational waves interfere with each other?
	2018-04-18: Using Stars to See Gravitational Waves 00:07: Now that gravitational waves are definitely a thing, it's time to think about some of the crazy things we can figure out with them. 00:31: We've already talked about the Laser Interferometer Gravitational-Wave Observatory, LIGO, and the first discovery of gravitational waves here. 02:09: Perhaps these gravitational waves signals were amplified by another phenomenon predicted by Einstein's general relativity, gravitational lensing. 02:19: ... paths of gravitational waves should also be warped by intervening gravitational fields which can ... 03:49: ... that live in the centers of galaxies, we need to observe gravitational waves in the 0.1 million hertz to 0.1 hertz ... 06:17: ... pulsar array volume due to the passage of impossibly vast gravitational waves. ... 06:44: Some scientists are even trying to see how gravitational waves should interact with stars. 07:21: ... but it demonstrates that in the right circumstances gravitational waves should be able to dump some of their energy into matter, for example, ... 07:52: ... binary supermassive black holes that are generating gravitational waves. ... 08:40: ... theory of relativity, which predicted the existence of gravitational waves, he had to master it precursor, Newtonian ... 02:09: Perhaps these gravitational waves signals were amplified by another phenomenon predicted by Einstein's general relativity, gravitational lensing.
	2018-04-11: The Physics of Life (ft. It's Okay to be Smart & PBS Eons!) 09:32: Waves and vortices have their own complex and regular structures, but they ultimately serve to dissipate the flow.
	2018-04-04: The Unruh Effect 09:46: ... even in classical systems, like this really cool study with water waves. ...
	2018-03-28: The Andromeda-Milky Way Collision 06:20: When those black holes are around a light year apart, they'll start losing orbital energy to gravitational waves.
	2018-03-21: Scientists Have Detected the First Stars 00:23: Not everything wows, like gravitational waves or space-faring sports cars.
	2018-01-17: Horizon Radiation 05:28: Sound waves can be described in terms of variation over time or variation over frequency.
	2018-01-10: What Do Stars Sound Like? 00:14: Believe it or not, we can now map the interiors of stars by listening to their harmonies as they vibrate with seismic waves. 01:21: I'm talking about seismic waves. 01:33: ... waves reflect around the stellar interior, setting up global oscillations, ... 02:34: ... earth, seismic waves are generated by earthquakes and can travel around the planet as ... 02:49: And these are true sound waves that echo around their interiors. 02:53: Because stars are fluid rather than solid, they don't support shear waves. 02:57: However, they do support two types of gravity waves. 03:01: Now, these are not gravitational waves. 03:04: Gravity waves result from the restoration of gravitational equilibrium. 03:14: In stars, these waves occur below the surface, g-waves, and on the surface, f-waves. 03:20: The latter are closely analogous to ocean surface waves on the earth. 03:24: However, it's the pressure waves-- the p-waves-- that really dominate in stars like the sun. 03:30: ... acoustic waves are generated by turbulence just below the surface of a star, just as ... 03:41: They start as traveling waves that can move throughout the stars in a structure. 03:45: ... ringing, a single traveling wave feeds its energy into standing pressure waves that cause the entire star to ... 08:12: ... surface of the sun-- is used to infer the current state of the standing waves throughout the ... 03:14: In stars, these waves occur below the surface, g-waves, and on the surface, f-waves. 01:33: ... waves reflect around the stellar interior, setting up global oscillations, natural ... 03:04: Gravity waves result from the restoration of gravitational equilibrium.
	2017-12-06: Understanding the Uncertainty Principle with Quantum Fourier Series 02:35: So let's choose a type of wave that's a little more intuitive, sound waves. 03:03: ... it can always be broken down into a combination of many simple sine waves of different ... 03:23: ... that any complex sound wave can be decomposed into a number of sine waves of different frequencies, each with a different strength, stacked on top ... 04:18: So we can make any shape sound wave with a series of sine waves of different frequencies. 05:01: Is it even possible to make an instantaneous spike at one point in time out of a bunch of sine waves that themselves extend infinitely through time? 05:12: ... point in time, you need to use infinitely many different frequency sine waves, each of which exists at all points in ... 05:41: That sounds an awful lot like a frequency-time uncertainty principle for sound waves. 07:08: ... now call matter waves wave functions, and we can describe them in terms of position or ... 07:50: But what does it even mean for a particle to be comprised of waves of many different positions or momenta? 08:48: ... now constrained in position, can only be described as a superposition of waves with a very large range of different momenta via a Fourier ... 09:50: It's an unavoidable outcome of describing particles as the superposition of waves. 09:55: Waves that can be represented in terms of either position or momentum. 07:08: ... now call matter waves wave functions, and we can describe them in terms of position or momentum, ...
	2017-10-25: The Missing Mass Mystery 04:28: ... like sound waves rippling outwards from high density regions, these baryonic acoustic ... 12:37: TS1336 was expecting last week's episode to be about the discovery of gravitational waves from merging neutron stars. 04:28: ... like sound waves rippling outwards from high density regions, these baryonic acoustic oscillations ...
	2017-10-19: The Nature of Nothing 08:51: ... organ pipe or a guitar string of a particular length only resonates with waves of certain frequencies, any non-resonant virtual photon would be ...
	2017-10-11: Absolute Cold 08:38: ... binary to spiral together from losing angular momentum to gravitational waves. ...
	2017-10-04: When Quasars Collide STJC 03:59: ... sides of the planet, and phase differences in the incoming radio waves are used to find the origin of each wave with incredible ... 06:14: Spiraling electrons produce radio waves a lots of frequencies all the way down to very low energies. 06:21: ... we think the matter should be so dense that the lowest energy radio waves have trouble escaping the ... 08:32: A lot of you are probably thinking, what about gravitational waves? 08:45: And can LIGO see those waves? 08:52: ... this system is definitely producing gravitational waves, but it's going to take many billions of years to lose enough angular ... 09:01: And while those waves may be powerful, they have an incredibly low frequency-- something like 1 ten trillionth of a hertz. 09:10: LIGO is sensitive to gravitational waves from 10 to 10,000 hertz.
	2017-09-20: The Future of Space Telescopes 11:00: ... tantalizing rumor that the LIGO Observatory had detected gravitational waves from the merger of a pair of neutron ... 11:33: Nicholas Martino asks whether gravitational waves are redshifted by the expansion of the universe. 11:40: They have to travel along the same space-time fabric as light waves, after all. 11:45: I mean, there are waves in that fabric. 11:48: So stretch out the fabric and you stretch out its waves.
	2017-09-13: Neutron Stars Collide in New LIGO Signal? 00:06: Last year, LIGO announced the detection of gravitational waves from the merger of two black holes. 00:15: ... rumor emerged, that LIGO had for the first time spotted gravitational waves from the collision of a pair of neutron ... 00:37: ... Gravitational Wave Observatory, LIGO, detected gravitational waves from a pair of merging black holes, an entirely new realm of the ... 02:55: In fact, the first real evidence of the existence of gravitational waves came from a pulsar. 03:09: This binary pair stirs up spacetime in its vicinity, creating ripples that travel outwards as gravitational waves. 04:46: Smaller mass means weaker gravitational waves. 09:59: Black hole mergers are dark, so we have to infer almost everything from the gravitational waves alone. 11:42: As it happens, Curiosity Stream has a really excellent overview of LIGO and gravitational waves. 11:49: "Gravitational Waves-- Rewinding Time" includes some fascinating behind-the-scenes footage at the observatories.
	2017-08-10: The One-Electron Universe 08:23: We now think of electrons as oscillations, as waves, in the more fundamental electron field.
	2017-07-07: Feynman's Infinite Quantum Paths 02:10: The professor replied, obviously, you have to add together the amplitudes of waves passing through all three slits. 13:12: ... in the late 19th century as the medium for the propagation of light waves. ... 13:22: It was imagined to be very closely analogous to air as the medium for propagation of sound waves. 02:10: The professor replied, obviously, you have to add together the amplitudes of waves passing through all three slits.
	2017-06-28: The First Quantum Field Theory 03:09: For example, in a 3D room full of air, sound waves are oscillations in air density.
	2017-06-21: Anti-Matter and Quantum Relativity 01:21: ... describes how these matter waves, represented as wave functions, change over time, and allowed physicists ...
	2017-05-31: The Fate of the First Stars 08:03: ... environment of the old universe, we expect that there were violent waves of star formation followed by cascades of supernova explosions, ripping ...
	2017-03-15: Time Crystals! 00:18: [MUSIC PLAYING] In "Space Time Journal Club," we review new scientific papers that are making waves.
	2017-02-02: The Geometry of Causality 10:50: Janna Levin's "Black Hole Blues" is a wonderful take on the new window that gravitational waves are opening on our universe.
	2017-01-25: Why Quasars are so Awesome 07:54: Waves of star formation, followed by waves of supernovae.
	2017-01-11: The EM Drive: Fact or Fantasy? 00:59: Most often, they turn out to be in error, like Opera's faster than light neutrinos and the BICEP2 primordial gravitational waves. 01:44: A resonant radiation field is induced inside, so microwave standing waves reflecting between the ends. 12:28: Speaking of not using radio, Richy Rich and Gareth Dean had a nice discussion on whether aliens would use radio waves. 01:44: A resonant radiation field is induced inside, so microwave standing waves reflecting between the ends.
	2017-01-04: How to See Black Holes + Kugelblitz Challenge Answer 02:33: ... recent observations of gravitational waves from a pair of merging black holes by LIGO could be considered our first ... 04:28: ... and microlensing studies, and of course, more LIGO gravitational waves observations, over the next few years, we'll have mapped the space ...
	2016-12-21: Have They Seen Us? 07:49: But if such radio waves travel to us from the earliest of times, then they become stretched out as they travel through an expanding universe.
	2016-11-30: Pilot Wave Theory and Quantum Realism 00:55: ... explanations claim stuff like things are both waves and particles at the same time, the act of observation defines reality, ... 03:25: ... guy who originally proposed the idea that matter could be described as waves right at the beginning of the quantum ... 03:36: De Broglie's theory reasoned that there was no need for quantum objects to transition in a mystical way between non-real waves and real particles. 03:46: Why not just have real waves that push around real particles?
	2016-10-12: Black Holes from the Dawn of Time 00:25: LIGO's recent observation of gravitational waves from merging black holes is a stunning confirmation of this fact.
	2016-08-10: How the Quantum Eraser Rewrites the Past 03:31: ... interference pattern happens because the waves emerging from each slit are what we call coherent, which is a fancy way ... 03:41: So the locations of peaks and valleys is predictable and stays consistent as the waves move forward. 03:49: This coherence is what allows the waves to produce the interference pattern in the first place. 03:31: ... interference pattern happens because the waves emerging from each slit are what we call coherent, which is a fancy way of saying ...
	2016-07-27: The Quantum Experiment that Broke Reality 00:45: Some distance away, those waves encounter a barrier with two gaps cut in it. 01:34: Any type of wave should make an interference pattern like this, for example, water waves and sound waves but also light waves. 02:33: So each photon is a little bundle of waves, waves of electromagnetic field, and each bundle can't be broken into smaller parts. 06:14: What are these waves of or waves in? 09:54: ... and quantum field theory tells us that all fundamental particles are waves in their own ... 10:06: This may give us a more physical medium that drives these waves of possibility. 00:45: Some distance away, those waves encounter a barrier with two gaps cut in it. 02:33: So each photon is a little bundle of waves, waves of electromagnetic field, and each bundle can't be broken into smaller parts.
	2016-07-20: The Future of Gravitational Waves 00:14: ... Gravitational Wave Observatory, LIGO, detected the gravitational waves from the merger of two black ... 04:07: Beyond the detection of gravitational waves, this is another awesome validation of the theory. 05:25: When European Virgo comes online later this year, we expect a massive improvement in our ability to locate the source of the waves.
	2016-06-29: Nuclear Physics Challenge 00:24: These matter waves don't have perfectly-defined positions, but rather, occupy a range of possible positions.
	2016-06-22: Planck's Constant and The Origin of Quantum Mechanics 14:34: That's exactly the same type of swirliness that primordial gravitational waves should produce. 14:45: Ed Eggermont wonders if gravitational waves are also subject to gravitational lensing. 14:52: Gravitational waves are ripples in the fabric of space time, so they have to go where the space time goes.
	2016-06-01: Is Quantum Tunneling Faster than Light? 05:38: Remember the LEGO interferometer that discovered gravitational waves?
	2016-04-27: What Does Dark Energy Really Do? 01:33: During that expansion, it increases the wavelength of these electromagnetic waves, resulting in what we see as redshift, cosmological redshift.
	2016-04-06: We Are Star Stuff 09:27: ... spiral in as they radiate away their orbital energy in gravitational waves. ...
	2016-03-23: How Cosmic Inflation Flattened the Universe 02:26: They're defined by how fast sound waves could have traveled by the time the CMB was created.
	2016-03-09: Cosmic Microwave Background Challenge 04:18: This coming Monday, March, 14th, I'll be participating in a public seminar on the new LIGO discovery of gravitational waves. 04:29: If you're in the area and would like to attend, please RSVP to pbsspacetime@gmail.com with the subject line NYC Gravitational Waves. 04:42: You'll learn way more about gravitational waves than on any YouTube show.
	2016-02-24: Why the Big Bang Definitely Happened 06:16: We see ripples of sound waves in the pattern of those fluctuations. 08:40: ... ago, the LIGO team announced the very first detection of gravitational waves. ... 09:41: ... that Advanced LIGO was turned on just in time to catch the gravitational waves from the merger of black ... 11:39: ... quote Lawrence Stanley, "OK, but until the discovery of gravitational waves can lower my mortgage and reduce the price of gas at the pump, it ...
	2016-02-11: LIGO's First Detection of Gravitational Waves! 00:05: Gravitational waves have been directly detected for the very first time. 00:17: ... existence of these waves is the last major prediction of Einstein's theory of general relativity ... 00:49: ... predicted that it should certainly detect the passage of gravitational waves, of ripples in the fabric of spacetime caused by extreme gravitational ... 01:19: ... the detection, we put together a video explaining what gravitational waves are, how they're formed, and exactly how advanced LIGO detects ... 01:53: Any orbiting pair of massive objects generates gravitational waves. 01:57: ... through orbiting extremely close together, produce gravitational waves strong enough for us to detect, at the ... 02:30: But gravitational waves carry energy, which is sapped from the orbital energy of the system. 02:51: And so this was a very convincing but indirect verification of gravitational waves. 02:57: ... the waves produced when these stellar cores are still distant from each other are ... 04:57: See, gravitational waves are inevitable if the theory is correct. 06:13: ... LIGO is sensitive to gravitational waves at frequencies produced by merging black holes and neutron stars, as ... 02:30: But gravitational waves carry energy, which is sapped from the orbital energy of the system. 02:57: ... the waves produced when these stellar cores are still distant from each other are far too ... 01:57: ... through orbiting extremely close together, produce gravitational waves strong enough for us to detect, at the ...
	2015-12-16: The Higgs Mechanism Explained 08:49: Gareth Dean asks about this whole thing about using gravitational waves to turn up the core temperature of a star. 08:55: ... so gravitational waves carry a lot of energy, and some of it can get dumped into a star by ...
	2015-12-09: How to Build a Black Hole 01:20: If you get impatient, you can turn up the core temperature by bombarding it with gravitational waves.
	2015-10-28: Is The Alcubierre Warp Drive Possible? 06:23: ... like a mini version of the one being used to detect gravitational waves, To measure the tiny changes in path length created by a warp ... 07:09: ... next episode of "Space Time." Last week, we talked about gravitational waves, and whether the advanced LIGO Observatory has maybe seen ... 07:31: It'll be an orbiting gravitational wave observatory designed to detect much higher frequency gravitational waves than advanced LIGO. 08:12: So now, the money is on the signal actually being due to dust, not G waves. 08:24: Now, MrSh1pman wants to know, if we find these G waves, will it change anything?
	2015-10-22: Have Gravitational Waves Been Discovered?!? 00:03: Gravitational waves are the last prediction of Einstein's Theory of General Relativity. 01:03: However, there's one last, incredible prediction that has never been directly observed-- gravitational waves. 01:37: Same deal with gravitational waves. 02:00: So a rotating sphere or a cylinder doesn't make waves. 02:08: ... a certain speed determined by the stiffness of the rubber, gravitational waves-- and indeed, gravity itself-- propagate according to the stiffness of ... 02:49: ... ripples on a pond or even electromagnetic waves-- which are all simple, up-down, longitudinal waves-- gravitational waves ... 03:11: Well, let's first think about all the sorts of things that might produce detectable gravitational waves. 03:42: And this change is for the most powerful waves that have likely ever passed through you. 04:07: And so it's no wonder that gravitational waves remain the only major prediction of GR without a direct measurement. 04:20: Gravitational waves carry energy. 05:21: ... paths just right, we can make the peaks of one of those electromagnetic waves line up with the valleys of the other, causing them to completely cancel ... 06:37: So how many g-m waves did LIGO find? 06:40: Well, between 2002 and 2010 when it ran, it found zero-- no gravitational waves at all. 04:20: Gravitational waves carry energy. 02:49: ... even electromagnetic waves-- which are all simple, up-down, longitudinal waves-- gravitational waves are what we call quadrupole ... 04:07: And so it's no wonder that gravitational waves remain the only major prediction of GR without a direct measurement.
	2015-10-15: 5 REAL Possibilities for Interstellar Travel 12:26: Ed Stephan asks why we're even talking about gravitational waves when none have ever been observed. 12:32: ... in the meantime, in pointing out the indirect detection of gravitational waves, Garreth Dean delivers the amazing quote, "So we haven't seen a duck, but ...
	2015-10-07: The Speed of Light is NOT About Light 08:29: ... limit also happens to define the speed of propagation of electromagnetic waves-- the speed of ... 08:57: So lights or photons, also gravitational waves and gluons all have no mass.
	2015-08-05: What Physics Teachers Get Wrong About Tides! 08:47: ... how Miller's planet in the movie "Interstellar" could've had such a huge waves without the astronauts themselves being stretched or ...
	2015-06-24: The Calendar, Australia & White Christmas 06:16: ... McLean asked, "if aliens can't pick up our radio waves, then why are we trying to listen for alien radio waves with SETI?" Well, ...
	2015-03-25: Cosmic Microwave Background Explained 01:46: It's emitting electromagnetic waves of all wavelengths. 03:16: And just like toasters, people and tacos, it was emitting a thermal distribution of electromagnetic waves.
	2015-02-25: How Do You Measure the Size of the Universe? 00:55: That's the part that we, in principle, can see with light or gravitational waves. 03:22: In more extreme cases, the wavelength can be stretched out of the visible spectrum altogether, into microwaves or radio waves.

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