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2022-12-14: How Can Matter Be BOTH Liquid AND Gas?

  • 18:57: SomeRandomGuy asks What would our night sky look like if our galactic centre had a Quasar?
  • 19:09: Quasars or “active galactic nuclei” glow from the heat energy of matter being ripped to shreds as it spirals towards a supermassive black hole.
  • 19:37: ... distance of the center of the Milky Way and you get that a Milky Way quasar shining at the Eddington limit would be about 3 times brighter on our ...

2022-11-23: How To See Black Holes By Catching Neutrinos

  • 08:59: The most powerful AGNs are called quasars, and shine out from across the universe.

2022-11-16: Are there Undiscovered Elements Beyond The Periodic Table?

  • 16:04: Today’s special shoutout goes to Glenn Sugden, who’s supporting us at the quasar level.

2022-10-19: The Equation That Explains (Nearly) Everything!

  • 15:40: ... very special thanks to Vivaan Gupta Vaka, who’s supporting us at the Quasar level. For those you who don’t know, quasars are the most brilliant ...

2022-10-12: The REAL Possibility of Mapping Alien Planets!

  • 15:45: ... and Sujasha Vaka, who are both supporting us at   the quasar level. Guys, we wanted  to show our appreciation by naming ...

2022-07-20: What If We Live in a Superdeterministic Universe?

  • 13:12: The same team followed up with a cosmic Bell test using rather more distant objects - quasars several billion light years away.

2022-01-27: How Does Gravity Escape A Black Hole?

  • 12:20: ... today’s special shoutout goes to Alex Kern who’s supporting us at the Quasar ...

2022-01-19: How To Build The Universe in a Computer

  • 08:45: ... codes are used to simulate  the flows of gas in galaxies and around quasars, used to simulate star and planet formation,   and even star ...
  • 09:28: In your quasar disk   you need to simulate separately how  light travels through the hot plasma.

2021-12-20: What Happens If A Black Hole Hits Earth?

  • 06:02: ... we “see” black holes like Cygnus X-1 or the supermassive black holes in quasars - from the radiation generated by the infalling, or accreting ...

2021-12-10: 2021 End of Year AMA!

  • 00:02: ... the distant objects through two parts through space i like to look at quasars that way quasars being gigantic black holes in the process of ...

2021-11-02: Is ACTION The Most Fundamental Property in Physics?

  • 14:57: ... keeping this show going. But today I want to give a huge shoutout to our Quasar supporter Michael Schneider. Hamilton's principle tells us that action ...

2021-09-21: How Electron Spin Makes Matter Possible

  • 14:58: ... to give a special thank you to Ethan Cohen who's supporting us at the quasar level. Ethan, you're about as far as I can imagine from being ...
  • 16:27: ... says that when they were in school quasars were just discovered and there was speculation that they might be white ...
  • 18:06: ... of the speed of light, regarding how fast gas can be blasted away from a quasar. ...
  • 18:19: ... means I'm not wrong! But also not useful. The broad emission lines of quasars show that the gas is typically moving away from the black hole a few ...

2021-09-07: First Detection of Light from Behind a Black Hole

  • 01:54: We’ve been using the same technique for decades to understand quasars.
  • 02:08: ... and reflects - reverberates - its way through the complex structure of a quasar. ...
  • 02:36: We do this by watching how the spectrum of the quasar changes over time.
  • 02:48: ... basically you watch the quasar, which is just a faint point of light on the sky, and stretch it into an ...
  • 03:41: AKA an accretion disk, and switching on the quasar Quasars are not what you’d call stable.
  • 05:22: But in a quasar, the gas is moving fast, and that motion shifts the wavelengths of the light as we see it.
  • 05:40: In the case of the quasar’s emission lines, gas is moving towards us and away from us at many different speeds.
  • 05:46: ... classic broad emission lines - perhaps the most striking feature of the quasar spectrum, and one that confused the hell out of the astronomers who ...
  • 06:35: ... the same time, the response of the gas on the far side of the quasar is slower than the gas of near side because the far-side’s light has to ...
  • 08:42: It turns out that all three types of motion are seen in different quasars.
  • 09:03: It’s really, really hard to do this stuff because it takes years for big, powerful quasars to finish responding to a flare in the core.
  • 09:18: We’ll be able to watch millions of quasars all do their thing at the same time.

2021-07-21: How Magnetism Shapes The Universe

  • 11:30: ... as an active galactic nucleus - the most powerful of which are called quasars. ...
  • 13:22: And today, our extra extra special shoutout goes to Stephen Wilcox who’s supporting us at the quasar level.

2021-03-16: The NEW Crisis in Cosmology

  • 10:40: ... of spacetime.   One manifestation of this is when a distant quasar - a giant, gas-guzzling black hole - happens to be   closely ...

2020-12-22: Navigating with Quantum Entanglement

  • 12:01: And today I want to give an extra extra special thank you to Hank S, who supports us at the quasar level.

2020-08-24: Can Future Colliders Break the Standard Model?

  • 07:25: ... using natural particle accelerators like the sun or supernovae or quasars or galactic magnetic fields, which continuously spray the earth with ...
  • 13:42: And today a special thankyou to Alec S-L, who’s supporting us at the quasar level.

2020-06-30: Dissolving an Event Horizon

  • 07:31: ... example, if there’s a disk of gas surrounding the black hole like in a quasar, then the gas only spirals inwards because angular momentum is carried ...

2020-06-22: Building Black Holes in a Lab

  • 00:16: ... of our galaxy, superheated disks of gas pouring into tiny spaces in quasars or X-ray binary systems. Gravitational waves that perfectly match our ...

2020-05-27: Does Gravity Require Extra Dimensions?

  • 13:04: ... and most especially to Christina Oegren, who’s supporting us at the quasar ...

2020-04-14: Was the Milky Way a Quasar?

  • 01:36: The most powerful AGNs are called quasars, and they can shine a thousand times brighter than their surrounding galaxy.
  • 01:44: We’ve talked quasars — and what makes them so awesome — in a previous episode.
  • 08:16: Now A full quasar might devour many millions of times the mass of the Sun over one active period, which could last for several million years.
  • 08:25: ... energy in the form of light before it hits the black hole, which is why quasars shine so ...
  • 09:00: Definitely not enough to turn Sag A* into a quasar.

2020-03-24: How Black Holes Spin Space Time

  • 01:01: ... we’ve witnessed the havoc they wreak on their surroundings in distant quasars and in our own galaxy, and we’ve even taken an image of a black hole ...
  • 06:48: ... feeding - perhaps devouring a companion star or, in the case of quasars, a bunch of its host galaxy’s gas - the ISCO is expected to eventually be ...

2020-02-11: Are Axions Dark Matter?

  • 09:45: ... other spacey tests for axions. Magnetars - highly magnetic pulsars - and quasars may convert some of their own gamma ray output into axions - and that ...

2020-01-27: Hacking the Nature of Reality

  • 13:58: ... captured and then brought together in the searing hot accretion disks of quasars. ...
  • 15:37: ... suggests that it's oxymoronic to say that “All you need is a little quasar" to catch black holes. Suggesting that there's no such thing as a little ...
  • 15:47: ... galactic nuclei come in many sizes - quasar is the name we use for the largest and most powerful, where you can ...
  • 15:56: ... quasars our powered by supermassive black holes a few tens of millions to 10 ...
  • 16:10: And below the quasar range we have weaker active nuclei.

2020-01-13: How To Capture Black Holes

  • 00:00: ... but how about black holes being captured by the screaming vortex of a quasar, where they merge and grow like some monstrous version of a solar system. ...
  • 00:24: ... 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 ...
  • 04:08: ... accelerate the mergers of these black holes: all you need is a little quasar. For the most part the supermassive black holes at galactic centers are, ...

2020-01-06: How To Detect a Neutrino

  • 09:42: ... so comments will return after we find him." "Thanks to our Quasar Supporters: Mark Heising Vinnie Falco" (text): "Matt is currently lost ...

2019-10-15: Loop Quantum Gravity Explained

  • 14:59: We do see this effect in the light from gravitationally lensed quasars and supernovae.

2019-08-26: How To Become an Astrophysicist + Challenge Question!

  • 00:00: ... using the Hubble Space Telescope to help unravel the connection between quasars and galaxies As many others also found the two evolved hand-in-hand Each ...

2019-07-25: Deciphering The Vast Scale of the Universe

  • 07:54: Those smaller dots at the edge of our surveys are quasars.
  • 08:16: ... see these most distant quasars, as well as the earliest galaxies or even black holes or worlds around ...

2019-07-01: Thorium and the Future of Nuclear Energy

  • 15:29: ... put, Steve! That's exactly what it is Chuck Ritter's Dorf asks, whether quasar jets and a preferred direction Relative to the galaxy as a whole and how ...
  • 16:45: ... full blown quasars the most luminous of accreting black holes or active galactic nuclei are ...

2019-06-20: The Quasar from The Beginning of Time

  • 01:50: ... one of our great surveys of the sky. Astronomers guessed the speck was a quasar - a vortex of radiant matter falling into a giant black ...
  • 02:06: ... quasars are the most luminous objects in the universe. What was strange about ...
  • 04:46: This is the instrument used to analyze the most distant quasar.
  • 05:05: When the light analyzed by this machine left its quasar, it was ultraviolet.
  • 05:12: ... how long that light has been traveling – 13.1 billion years, meaning the quasar lived when the universe was only 5% its current ...
  • 05:35: There's a broad blank patch in the quasar's spectrum – it's a stretch of nothing that tells us a ton.
  • 06:07: But this quasar shines out from the era of those first stars before they'd finished the job of reionization.
  • 06:15: Much of the quasars once ultraviolet light was sucked up before it escaped the early universe.
  • 06:21: And what about the supermassive black hole at the center of the quasar?

2019-06-17: How Black Holes Kill Galaxies

  • 00:08: ... as a bit of a shock they were discovered as the driving force behind Quasars where matter is heated to extreme Incandescence before it plunges into ...
  • 04:05: ... to catch up like a puppy growing into its giant feet in fact we've seen quasars shining out from less than a Billion years after the Big bang with ...
  • 06:33: ... different ways it can happen via Black Hole but all of them involve a Quasar switching on and blasting the crap out of the galaxy's gas rewinding a ...
  • 07:21: ... Quasars's intense brightness and its powerful winds and jets can dump an enormous ...
  • 10:49: ... the modern universe Giant Dead galaxies harbor fossil quasars supermassive Black Holes whose close connection to their surrounding ...

2019-06-06: The Alchemy of Neutron Star Collisions

  • 02:47: ... to use the lyman-alpha forest to map where along the line of sight to a quasar there are clouds of hydrogen gas and learn about their size and density ...
  • 12:15: ... so little in this case from a single point of light that is that distant quasar." - Jan Pieter Cornet asks something that I hoped one of you would: "if ...

2019-05-16: The Cosmic Dark Ages

  • 06:39: ... But before we get to that, I want to take a moment to talk about quasars. It’s relevant, trust ...
  • 06:51: Not that I should need a reason to talk about quasars.
  • 07:19: ... by vortices of superheated plasma, these black holes powered the first quasars. They shone with the brightness of hundreds of trillions of Suns, yet ...
  • 08:36: ... here’s the scenario – a quasar shines out from the epoch of reionization. Lyman-alpha photons from that ...
  • 09:21: ... rest of the quasar’s light continues on its way towards us, but the universe keeps expanding. ...
  • 10:10: ... is the spectrum of a quasar from the epoch of reionization. All of this light comes from the ...
  • 10:47: ... reach us. The jagged region is the Lyman-alpha forest, where the quasar light passed through individual clouds of neutral gas, each of which cut ...
  • 11:06: Oh, and right next to the Lyman-alpha cutoff we see a little light that made it through due to the ionized bubble around the quasar itself.
  • 11:17: ... ionized. And the scant Lyman-alpha light that made it through due to the quasar’s ionization bubble can tell us how much neutral hydrogen was left at the ...
  • 11:49: ... tells us when the dark ages ended, and light absorbed from the first quasars tracks the last phases of the subsequent ...

2019-05-09: Why Quantum Computing Requires Quantum Cryptography

  • 16:16: That's probably around 5 times larger than the event horizon, in the case of this quasar.

2019-04-24: No Dark Matter = Proof of Dark Matter?

  • 00:03: ... elliptical galaxies while perhaps that elliptical galaxy once harbored a quasar its central black hole underwent a feeding frenzy that blasted enough ...

2019-03-28: Could the Universe End by Tearing Apart Every Atom?

  • 12:40: ... acceleration rate measured using distant quasars hints at an equation of state parameter slightly less than negative 1 ...
  • 13:18: ... energy may be increasing in strength based on measurements of distant quasars. ...

2019-03-20: Is Dark Energy Getting Stronger?

  • 00:45: ... Nature Astronomy, “Cosmological constraints from the Hubble diagram of quasars at high redshifts” by Risaliti and ...
  • 06:31: Enter the quasar.
  • 06:41: Quasars are a black hole feeding frenzy.
  • 07:00: We call such objects quasars.
  • 07:03: Quasars are, at first glance, pretty crappy standard candles.
  • 07:13: It’s very hard to distinguish between a brighter quasar that’s further away or a fainter quasar that’s closer to us.
  • 07:20: In general quasars are a hot mess.
  • 07:51: The new study uses the brightness X-ray corona to figure out the true energy output of quasars.
  • 08:17: ... quasars shine in X-rays due to this process, and as you might expect, the ...
  • 09:12: See, the ratio between the amounts of X-ray versus ultraviolet light depends on true ultraviolet energy output of the quasar.
  • 09:40: But if you make the measurement with enough quasars then this scatter can be averaged away.
  • 09:46: Fortunately there are a LOT of quasars out there – far more than known supernovae.
  • 09:52: Risaliti and Lusso cobbled together around 1,600 quasars with both ultraviolent and X-ray observations.
  • 10:25: ... basically shows the distance of the quasar that we get from the UV-to-X-ray ratio, versus the redshift, which is ...
  • 10:42: The yellow and blue dots are our quasars – 1600 of them.
  • 11:07: ... means the light from these quasars appears more stretched out – more redshifted on average – than it should ...
  • 11:35: ... that could explain the extra stretching of the light from these distant quasars. ...
  • 12:59: In fact there are alternative ideas that try to resolve the conflict between the CMB, supernova, and now the quasar results.
  • 13:27: ... a systematic problem with the way supernova and/or quasar distances are determined, or even an issue with the cosmic microwave ...
  • 13:36: ... there are still relatively few very distant quasars with good X-ray measurements, so maybe the random variations in the ...

2018-09-20: Quantum Gravity and the Hardest Problem in Physics

  • 12:46: ... a special huge thank you to Justin Lloyd, who's contributing at the Quasar level-- Justin, as a special thanks, we're sending you a box of ...

2018-05-16: Noether's Theorem and The Symmetries of Reality

  • 11:05: ... galaxies, and see more distant supernovae, monitoring more distant quasars for their ...

2018-05-09: How Gaia Changed Astronomy Forever

  • 07:51: Gaia has also mapped the position and brightnesses of over half a million quasars-- the cause of distant active galaxies.

2018-04-18: Using Stars to See Gravitational Waves

  • 01:53: Or perhaps they grew after being swept up in a quasar accretion disk.

2018-03-28: The Andromeda-Milky Way Collision

  • 06:29: The resulting super supermassive black hole may briefly power a new quasar as it consumes any gas that also ended up in the core.

2018-03-07: Should Space be Privatized?

  • 10:13: And today's extra huge thanks goes to Roman Pinchuk, who contributes at the Quasar Level.

2017-12-06: Understanding the Uncertainty Principle with Quantum Fourier Series

  • 13:58: ... hypothesized to be the light echo from a dead quasar that was once in that galaxy, so the cloud of gas ionized by the last ...

2017-10-25: The Missing Mass Mystery

  • 06:39: Absorption features in the light of distant quasars reveal this gas lurking between clusters of galaxies.

2017-10-11: Absolute Cold

  • 09:47: There it might trigger some quasar activity until it all gets gobbled up by the black hole.

2017-10-04: When Quasars Collide STJC

  • 02:19: This is what causes the quasar phenomenon.
  • 02:39: Actually, let me say a bit more about quasars.
  • 02:55: Quasar is the term for the most powerful AGNs, and they contain SMBHs with up to billions of Suns in mass.
  • 06:54: The only way this is possible is with two separate black holes, each one powering its own mini quasar.
  • 10:31: Justin, your contributions at the quasar level have been an amazing help.
  • 10:44: We will spend it exclusively on animating black holes and quasars, and also pizza.

2017-09-28: Are the Fundamental Constants Changing?

  • 06:34: The key to this measurement is quasars.
  • 06:37: Remember quasars, insanely luminous maelstrom drums of superheated matter surrounding the most massive black holes in the universe?
  • 06:48: When a quasar's light passes through giant clouds of gas on its way to us, elements in those clouds absorb photons to produce spectral lines.
  • 06:58: By looking at many quasars, we can find absorbing clouds that existed in different past epochs of the universe.
  • 07:18: They used the Keck telescope in Hawaii to study iron and magnesium absorption lines from clouds along the lines of sight of 143 quasars.
  • 08:26: ... is really, really difficult. Photons from these extremely distant quasars and gas clouds are massively redshifted-- their wavelengths stretched ...

2017-09-20: The Future of Space Telescopes

  • 04:30: Besides Earth-like exoplanets, the starshade would also be an enormous help in studying quasars and other high-contrast phenomena.
  • 10:42: And a very special thanks to Dean Fuqua for supporting us at the Quasar level.

2017-09-13: Neutron Stars Collide in New LIGO Signal?

  • 12:16: And an extra huge thanks to Mark Rosenthal for supporting us at the quasar level.

2017-08-30: White Holes

  • 00:50: ... that black holes are very real with convincing evidence that quasars, x-ray binaries, even the center of our own Milky Way galaxy harbor these ...

2017-08-16: Extraterrestrial Superstorms

  • 11:40: And a very special thanks to quasar supporter Mars Yentur.

2017-07-26: The Secrets of Feynman Diagrams

  • 12:14: And a very special thanks to Mayank Mehrotra for supporting us at the quasar level.

2017-07-07: Feynman's Infinite Quantum Paths

  • 11:45: And a special big thanks to Max Levine for supporting us at the quasar level.

2017-05-31: The Fate of the First Stars

  • 09:26: Such black holes power quasars, which themselves, had a huge influence on the later evolution of our universe.

2017-05-03: Are We Living in an Ancestor Simulation? ft. Neil deGrasse Tyson

  • 12:48: And an extra huge thanks to Avan and Kyan Griggs for supporting us at the Quasar level.

2017-04-19: The Oh My God Particle

  • 06:41: But they may come from magnetic acceleration in quasars, or perhaps they're blasted out in gamma ray bursts.
  • 07:59: But at that distance, sources like quasars and gamma ray bursts should be very obvious.

2017-04-05: Telescopes on the Moon

  • 10:59: Quasars do this all the time to power their insane luminosities.

2017-02-15: Telescopes of Tomorrow

  • 10:57: And a specialty thank you to Jelle Slaets, who's supporting us at the Quasar Level.

2017-02-02: The Geometry of Causality

  • 10:58: ... Scharf's "Gravity's Engines" gets into my favorite space things of all-- quasars, and especially how important they are in the evolution of the ...
  • 11:47: We skipped comments last week because I was at the beach, so today, we're tackling both phantom singularity and quasars.
  • 12:58: Joan Eunice asks whether there's a spot near a quasar where a stable orbit could be created, and what would time dilation be like there?
  • 14:02: Well, although quasar accretion disks can reach some pretty crazy temperatures, they aren't particularly dense.
  • 15:13: "When my dad was in college, he needed one of those easy classes for credit, so he took a class on quasars and black holes in the universe.

2017-01-25: Why Quasars are so Awesome

  • 00:06: One of the most enigmatic of all astrophysical phenomena is the mighty quasar.
  • 00:50: Of course, everyone knows that quasars are the most awesome of all.
  • 01:26: Yep, quasars are clearly the most metal of all the space things.
  • 01:36: Quasars helped shape our universe.
  • 03:00: Later, to become quasar.
  • 04:33: The heat glow of the accretion disk is so bright that we can see quasars to the ends of the universe.
  • 04:56: ... up and collimated, channeled into jets that erupt from the poles of the quasar. ...
  • 05:18: Looking down onto a bright accretion disk, we see a quasar in all of its glory.
  • 05:34: ... if such an edge-on quasar has powerful jets, we see them blasting through the galaxy and even ...
  • 06:30: This is a simplified description of our modern understanding of quasars and active galactic nuclei.
  • 06:55: ... for 3C273, the nearest bright quasar, the accretion disk falls into a region less than 100,000 times smaller ...
  • 07:16: Anything as energetic as a quasar must have had an influence on the universe.
  • 07:21: The first quasars turned on in a very young universe that was still thick with the raw hydrogen gas produced in the Big Bang.
  • 08:12: However, the same rich gas supplies that fueled those starbursts also gave rise to the epoch of quasars.
  • 08:30: Accretion disks formed, and many knew quasars were born.
  • 08:35: Each burst of quasar activity in a given galaxy probably only lasts 10 million years or so.
  • 08:52: A few billion years after the Big Bang, when the universe was around a quarter of its current age, both starbursts and quasars started to dwindle.
  • 09:09: We are now well out of the quasar epoch.
  • 09:13: Active galactic nuclei still do fire up in the modern universe, although usually they are at full quasar power.
  • 09:24: But good old 3C273 is a full blown quasar.
  • 09:32: Although it's far away, its light comes to us from a time long after the peak of the quasar epoch.
  • 09:45: ... deliver one last wave of fuel to the combined galactic core, and a new quasar will shine forth, illuminating this little patch of ...
  • 11:13: And a very, very big thank you to Tambe Barsbay, who's supporting us at the quasar level.
  • 11:18: Tambe, your own personal spacetime quasar is in the mail.

2017-01-11: The EM Drive: Fact or Fantasy?

  • 09:29: ... to Joel Brinton for his incredibly generous Patreon sponsorship at the quasar ...

2017-01-04: How to See Black Holes + Kugelblitz Challenge Answer

  • 01:00: This gives us things like quasars, supermassive black holes in galaxy cores that feed on a superheated whirlpool of gas.

2016-12-21: Have They Seen Us?

  • 13:08: I want to give a very special shout-out to Luna IT Solutions, who are sponsoring us at the quasar level.

2016-10-12: Black Holes from the Dawn of Time

  • 05:27: In stars in our galaxy, in distant quasars, even in gamma ray bursts.

2016-06-22: Planck's Constant and The Origin of Quantum Mechanics

  • 12:15: But perfect alignment is almost impossible for something as small as a quasar.
  • 12:19: The quasar is away slightly offset from the optical axis.
  • 13:03: There are some cases where you see four individual quasar images connected by an Einstein ring.
  • 13:10: That Einstein ring is actually the galaxy that hosts the quasar.

2016-06-15: The Strange Universe of Gravitational Lensing

  • 04:51: This is the Einstein Cross, an extremely luminous distant quasar powered by a supermassive black hole feeding on its surroundings.
  • 05:00: In fact, each of these spots is that one quasar viewed via four different paths through the universe.
  • 05:14: To see multiple quasar images, you need a near-perfect alignment between the lensing galaxy and the quasar.
  • 05:22: While we know of a 200,000 quasars, we only know of about 100 that are lensed this way.
  • 05:28: The flickering of the lensed quasar images carries with it many secrets.
  • 05:33: The quasar is a vortex of superheated matter falling into a black hole.
  • 06:08: Also coded in this flickering is information about the heart of the quasar itself.
  • 06:25: As those stars sweep in front of the quasars in a vortex, its different parts change in magnification to different degrees and at different times.

2016-03-16: Why is the Earth Round and the Milky Way Flat?

  • 00:23: It loves building spheres like stars, planets, and moons, and disks like spiral galaxies, solar systems, and some crazy stuff like quasars.
  • 08:20: This is not true of things like spiral galaxies, solar systems, and the whirlpools of gas around quasars.

2016-02-17: Planet X Discovered?? + Challenge Winners!

  • 07:01: Quasar jets, pointing towards us, appear crazily bright.

2015-11-05: Why Haven't We Found Alien Life?

  • 09:48: ... past supernova explosions, but after the violence of the starburst and quasar ...

2015-08-27: Watch THIS! (New Host + Challenge Winners)

  • 03:34: Which quasar is the most distant object ever observed?
  • 03:38: It's not a quasar at all.
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