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	2022-09-21: Science of the James Webb Telescope Explained! 04:03: The very first galaxies shone with intense ultraviolet light as the dense, young gas of the early universe collapsed into the first stars.
	2022-06-22: Is Interstellar Travel Impossible? 08:02: Interstellar space is quite a bit less dense than the upper atmosphere - by a factor of around 10^16.
	2022-05-25: The Evolution of the Modern Milky Way Galaxy 02:19: ... thing   is sprinkled with wayward stars and ancient,  dense mini-galaxies called globular clusters.   But mostly the halo ...
	2022-05-04: Space DOES NOT Expand Everywhere 08:34: ... apart objects and the spacetime grids they trace. But in sufficiently dense regions gravity won and there the only evidence of the greater expansion ...
	2022-03-30: Could The Universe Be Inside A Black Hole? 08:53: They get denser towards the center and have plenty of pressure.
	2022-01-12: How To Simulate The Universe With DFT 00:18: That’s how insanely information dense the quantum wavefunction really is.
	2021-12-20: What Happens If A Black Hole Hits Earth? 01:49: ... There would have been some regions that just happened to be especially dense. Countless black holes might have formed at the earliest of times, while ...
	2021-11-17: Are Black Holes Actually Fuzzballs? 08:55: In fact, if you have a bunch of strings dense enough to form a black hole in general relativity, it wouldn’t actually collapse.
	2021-09-21: How Electron Spin Makes Matter Possible 17:29: ... own particle, moving around the lattice. But this pseudoparticle is less dense that its surroundings, so it eventually rises to the surface and so gets ...
	2021-09-15: Neutron Stars: The Most Extreme Objects in the Universe 09:34: ... form sheets. That’s right - nuclear lasagna.  And because it’s so dense, it’s really  hard to bend and move this stuff. Nuclear ... 02:35: ... out  very tenuous - almost a vacuum,   and then gets denser as we drop.  But the similarities end there.   Earth’s ...
	2021-09-07: First Detection of Light from Behind a Black Hole 03:48: They sputter and flare with violent events, for example as dense clumps of gas hitting the center, or magnetic instabilities shaking things up.
	2021-08-03: How An Extreme New Star Could Change All Cosmology 12:16: ... may get its explosive finale after all. A typical white dwarf is pretty dense, at around a metric ton per cubic ... 12:50: ... is a 1000 times denser still. That means it can support incredibly energetic electrons in its ...
	2021-07-21: How Magnetism Shapes The Universe 08:30: These are the densest regions of those galactic disks - places where magnetic fields have confined the charged particles of the interstellar plasma.
	2021-07-07: Electrons DO NOT Spin 15:31: ... t=0, the universe was extremely compact - which meant hot and  dense, and it was also extremely smooth. The compact part is where the low ...
	2021-06-09: Are We Running Out of Space Above Earth? 15:32: ... asked whether a region dense in Planck relics would emit high-energy radiation as the relics merged ... 09:18: But these lowest orbits are the most useful and cheapest to launch to - and so are the most densely populated.
	2021-04-13: What If Dark Matter Is Just Black Holes? 06:53: ... white dwarf, but it would deposit enough heat to allow the stars' ultra dense carbon and oxygen to undergo nuclear ... 07:14: They're so dense, that they would stop a microscopic black hole in its tracks. 10:01: ... galaxies are so small and dense that even black holes with tens of solar masses should have trickled to ... 06:53: ... white dwarf, but it would deposit enough heat to allow the stars' ultra dense carbon and oxygen to undergo nuclear ...
	2021-03-16: The NEW Crisis in Cosmology 10:08: ... of ancient sound waves   that reverberated through the hot, dense plasma of the early universe. Now those ripples are ...
	2020-11-18: The Arrow of Time and How to Reverse It 07:17: ... galaxies and the particles that comprise them back and calculate a much denser, more “special” arrangement - in fact an incredibly low entropy ...
	2020-10-27: How The Penrose Singularity Theorem Predicts The End of Space Time 01:17: ... after Einstein published them,   revealing that a sufficiently dense ball of matter would be surrounded by a surface where time ... 01:58: ... enough to produce an event horizon - nor   even whether such dense matter would  really contract into a single point.   It ... 10:15: ... could, for example, miss and weave past each other in an insanely dense but not   infinitely dense knot. This might be the ... 01:17: ... after Einstein published them,   revealing that a sufficiently dense ball of matter would be surrounded by a surface where time ... 10:15: ... past each other in an insanely dense but not   infinitely dense knot. This might be the case if the universe underwent cyclic big ... 01:58: ... enough to produce an event horizon - nor   even whether such dense matter would  really contract into a single point.   It only ... 09:31: ... that the universe is expanding, and probably started in a much denser state. In fact the latter   had been verified by the detection ...
	2020-09-01: How Do We Know What Stars Are Made Of? 04:22: Once it gets close to the surface, material is much less dense, so there are fewer free electrons to do the scattering.
	2020-08-17: How Stars Destroy Each Other 12:12: ... black holes may have formed from the extremely dense matter of the early universe, and these would have different mass ... 03:30: They result when denser streams of matter hit the white dwarf and flare due to heat, but do not produce the storm of fusion of the classical nova. 06:03: ... binaries, that fluctuation includes powerful flares, resulting from denser clumps of material hitting the rapidly rotating surface of the neutron ... 03:30: They result when denser streams of matter hit the white dwarf and flare due to heat, but do not produce the storm of fusion of the classical nova.
	2020-06-30: Dissolving an Event Horizon 01:12: Without it, the infinitely dense singularity and its surrounding madness is exposed to the outside universe.
	2020-06-22: Building Black Holes in a Lab 03:26: ... - right down to the emission of Hawking radiation. The details are a bit dense for YouTube, but I’ll link a lovely paper by Matt Visser for those who ...
	2020-05-04: How We Know The Universe is Ancient 03:24: ... no alternative - the universe must have once been in an extremely hot, dense state, and expanded from there. Astronomers call this the big bang model ... 09:39: ... For a while we thought we’d found globular clusters - ancient, dense groups of stars - that were 15 billion years old. As bad as finding ... 03:24: ... no alternative - the universe must have once been in an extremely hot, dense state, and expanded from there. Astronomers call this the big bang model of the ...
	2020-01-20: Solving the Three Body Problem 11:21: ... This looks to be incredibly useful for understanding the evolution of dense regions of the universe, where three-body systems of stars or black ...
	2020-01-13: How To Capture Black Holes 00:59: ... may end their lives to leave a pair of binary black holes. And in very dense environments like the cores of galaxies, lone black holes may find each ... 03:34: ... falling together. Now binary black hole pairs surely do exist in the dense galactic center, but they may have trouble merging in such a dense ... 00:59: ... may end their lives to leave a pair of binary black holes. And in very dense environments like the cores of galaxies, lone black holes may find each other and ... 03:34: ... falling together. Now binary black hole pairs surely do exist in the dense galactic center, but they may have trouble merging in such a dense environment. ...
	2019-12-17: Do Black Holes Create New Universes? 03:26: ... collapses, its mass doesn’t all end up stuck in the central, infinitely dense ... 09:09: ... mostly produce neutron stars - planet sized balls of neutrons so dense that they teeter on the edge of collapsing into a black ... 03:26: ... collapses, its mass doesn’t all end up stuck in the central, infinitely dense singularity. ... 09:34: The resulting material is even denser than the original neutron star, and so brings the star closer to collapse.
	2019-08-19: What Happened Before the Big Bang? 00:04: That is as long as you define 'The Big Bang' as the universe's early hot dense expanding state that's well described by Einstein's equations. 05:26: This gives us the expanding hot dense universe that we know and love in our Big Bang model. 00:04: That is as long as you define 'The Big Bang' as the universe's early hot dense expanding state that's well described by Einstein's equations. 05:26: This gives us the expanding hot dense universe that we know and love in our Big Bang model.
	2019-08-06: What Caused the Big Bang? 10:59: ... evolve as the rest of the Big Bang story predicts: An extremely hot dense ocean of matter and radiation that slowly cools and disperses and forms ...
	2019-07-18: Did Time Start at the Big Bang? 01:22: ... Theory is just a theory" Let me be very clear, the evidence for a hot dense early universe is practically ... 01:56: ... Whose ratio is exactly what we expect if the entire universe was a dense billions of degrees nuclear furnace for the first several minutes of its ... 04:38: ... it enough times and the universe could end up as hot and dense as you like But it'll still be infinite, spatially, the scale factor is ... 01:56: ... Whose ratio is exactly what we expect if the entire universe was a dense billions of degrees nuclear furnace for the first several minutes of its ... 01:22: ... Theory is just a theory" Let me be very clear, the evidence for a hot dense early universe is practically ...
	2019-06-17: How Black Holes Kill Galaxies 07:21: ... across the Universe slowly rose it became concentrated in the most denser region of the Universe where giant ellipticals assembled the rising ... 02:54: ... we look out into the Universe so galaxies first grew in clusters in the densest parts of the Universe Places where enormous worlds of Dark Matter pulled ... 07:21: ... to do so this is mainly due to star formation shutting down in the densest parts of the Universe which as I mentioned is strange given i should ... 02:54: ... we look out into the Universe so galaxies first grew in clusters in the densest parts of the Universe Places where enormous worlds of Dark Matter pulled in ... 07:21: ... to do so this is mainly due to star formation shutting down in the densest parts of the Universe which as I mentioned is strange given i should still ...
	2019-06-06: The Alchemy of Neutron Star Collisions 13:02: ... 300 Kelvin. And Spluff5 asks us another related question, "how dense was the gas just after recombination?" - well let's figure it out the ...
	2019-05-09: Why Quantum Computing Requires Quantum Cryptography 15:35: But dark matter alone could never clump together densely enough to produce a black hole by itself.
	2019-03-06: The Impossibility of Perpetual Motion Machines 14:50: More dense regions were a little hotter, so recombination started later in those.
	2019-02-20: Secrets of the Cosmic Microwave Background 00:08: ... Background radiation The remnants of the heat glow released when the hot dense early Universe became transparent for the first time It sounds like ...
	2019-01-24: The Crisis in Cosmology 07:07: The Cosmic Microwave Background is the remnant heat glow of the universe's initial hot dense state. 07:46: ...and also slightly more dense These over-densities... 07:07: The Cosmic Microwave Background is the remnant heat glow of the universe's initial hot dense state.
	2018-08-23: How Will the Universe End? 08:38: ... annihilate themselves as they collide with each other or be captured by dense stellar remnants during the Degenerate Age and, ultimately, end up in ... 10:11: Black dwarfs decay into iron stars-- still degenerate and insanely dense, but now perfect balls of iron. 08:38: ... annihilate themselves as they collide with each other or be captured by dense stellar remnants during the Degenerate Age and, ultimately, end up in black ... 04:15: It's so densely packed that all possible quantum states are completely filled and no further collapse is possible, short of becoming a black hole.
	2018-05-02: The Star at the End of Time 09:24: Joshua Hillerup asks whether dynamical friction leads to less dark matter near the centers of galaxies since dark matter's not very dense. 09:54: ... that the supermassive black hole in our galaxy center is in itself a dense swarm of smaller black holes in a shared orbit amounting to the same ... 09:41: ... light years of the Milky Way stellar disk and the much smaller and denser stellar ...
	2018-04-25: Black Hole Swarms 01:38: Well, the simple answer is straightforward-- dense things sink. 01:49: Dense elements, like iron, sink to the centers of forming planetary bodies in a process called differentiation. 03:50: They're like ancient, extremely dense mini-galaxies, containing millions of stars. 01:49: Dense elements, like iron, sink to the centers of forming planetary bodies in a process called differentiation. 03:50: They're like ancient, extremely dense mini-galaxies, containing millions of stars. 01:38: Well, the simple answer is straightforward-- dense things sink. 00:24: The stars are so densely packed that the night sky would be 500 times brighter than our own. 08:05: ... black holes are so densely packed in the centers of galaxies, then we should probably know that, if ... 00:24: The stars are so densely packed that the night sky would be 500 times brighter than our own. 08:05: ... black holes are so densely packed in the centers of galaxies, then we should probably know that, if we ... 01:43: Colder and hence denser water or air, sinks to the bottom of the ocean or the atmosphere. 01:56: And the densest, stellar objects, like black holes, sink to the centers of galaxies or star clusters.
	2018-04-18: Using Stars to See Gravitational Waves 07:52: ... it may be possible to observe this effect in the dense star fields of galactic cores if those galaxies also contain binary ...
	2018-04-11: The Physics of Life (ft. It's Okay to be Smart & PBS Eons!) 00:56: A hot cup of coffee will tend towards the same temperature as the room, and the hot, dense of our universe must expand. 01:24: ... the matter in the observable universe being crunched into an infinitely dense point are low ...
	2018-01-24: The End of the Habitable Zone 01:28: ... collapse from a giant gas cloud was halted as soon as the core became dense enough, dense enough for fusion to produce exactly the energy to balance ...
	2017-11-08: Zero-Point Energy Demystified 03:10: But try to drive your car in a dense 1,500 Kelvin atmosphere, and the piston has no reason to rise.
	2017-10-25: The Missing Mass Mystery 05:37: In the nexuses between filaments matter is dense enough for galaxies to form. 06:15: We typically see that stuff inside galaxy clusters where the plasma is relatively dense and is energized by the light of the galaxies themselves. 07:08: But it can't be so hot or dense as to emit detectable X-rays. 10:35: As those baryons fall into the dense nexuses of the cosmic web, they'll feed galaxies with material to form new stars.
	2017-10-04: When Quasars Collide STJC 06:21: ... the black hole where the jet begins, we think the matter should be so dense that the lowest energy radio waves have trouble escaping the ... 05:27: ... can splatter as their fuel supply changes or as the jets smash into denser regions of the surrounding ...
	2017-09-20: The Future of Space Telescopes 01:22: But these planets are extremely difficult to directly image because they are dense and small.
	2017-09-13: Neutron Stars Collide in New LIGO Signal? 01:54: When a massive star ends its life in a supernova explosion, it leaves behind an ultra dense core.
	2017-08-16: Extraterrestrial Superstorms 05:21: All of this happens in the troposphere, the densest and innermost layer of the atmosphere.
	2017-08-02: Dark Flow 01:44: The CMB is the leftover heat glow from the hot dense early universe.
	2017-05-31: The Fate of the First Stars 02:18: Today, they're found in the galactic bulge or in globular clusters, which are ancient, dense islands of stars that orbit far out in the galactic halo.
	2017-04-26: Are You a Boltzmann Brain? 01:04: For example, the hot, dense gas in a recently fired engine piston only expands because it's surrounded by a colder, less dense environment. 01:18: But if you put the compressed piston in an environment that's full of equally hot, dense gas, nothing happens. 04:26: ... will occasionally converge into a dense environment like a black hole or a galaxy, or into a complex arrangement ... 01:04: For example, the hot, dense gas in a recently fired engine piston only expands because it's surrounded by a colder, less dense environment. 04:26: ... will occasionally converge into a dense environment like a black hole or a galaxy, or into a complex arrangement like a ... 01:04: For example, the hot, dense gas in a recently fired engine piston only expands because it's surrounded by a colder, less dense environment. 01:18: But if you put the compressed piston in an environment that's full of equally hot, dense gas, nothing happens.
	2017-03-01: The Treasures of Trappist-1 03:23: But in that densely packed system, it covers three of the planets.
	2017-02-22: The Eye of Sauron Reveals a Forming Solar System! 02:14: Start with a dense core in a giant molecular cloud. 02:38: The protostar continues to collapse more slowly until eventually the core gets hot and dense enough to ignite in fusion. 02:14: Start with a dense core in a giant molecular cloud.
	2017-02-02: The Geometry of Causality 14:02: Well, although quasar accretion disks can reach some pretty crazy temperatures, they aren't particularly dense.
	2017-01-19: The Phantom Singularity 01:43: ... often use the word singularity to describe the hypothetically infinitely dense core of a black hole, but in math the meaning of this word is much more ...
	2016-12-14: Escape The Kugelblitz Challenge 03:51: OK, in the case of the collapsing start, that's still a core, is going to be an insanely hot, dense place and not great for observers.
	2016-11-30: Pilot Wave Theory and Quantum Realism 13:45: And the problem is that the universe at this time wasn't dense enough and was expanding too quickly for strange matter to form in any great abundance. 15:45: Also, it's dense but not necessarily strong.
	2016-11-16: Strange Stars 04:50: In that state, it forms a superfluid rather than a plasma, a superfluid even denser than neutronium. 02:49: ... quickly gives way to a fluid of almost pure neutrons, neutronium, the densest known substance in the ...
	2016-10-19: The First Humans on Mars 03:35: That means either living underground or building dense shelters from local material. 08:56: ... possibility that primordial black holes formed in the insanely dense conditions right after the Big Bang and that these might still be around ... 03:35: That means either living underground or building dense shelters from local material.
	2016-09-29: Life on Europa? 06:11: That surface is by far the most densely populated region in the oceans beneath the Antarctic Sea ice.
	2016-04-27: What Does Dark Energy Really Do? 04:40: Now, that actually points to a more dense universe.
	2016-04-20: Why the Universe Needs Dark Energy 10:38: Even with dark matter, the universe is just not dense enough to recollapse. 09:43: Within these regions, the shape of spacetime is dominated by the gravitational field of the densely packed matter.
	2016-04-06: We Are Star Stuff 03:28: ... about 20 minutes after the Big Bang, the entire universe was hot and dense enough for nuclear fusion, for protons to slam together hard enough to ...
	2016-03-16: Why is the Earth Round and the Milky Way Flat? 11:12: Felix Ironfist asks, "why didn't the universe collapse into a black hole, if it was so dense and massive?" This is a classic question.
	2016-03-09: Cosmic Microwave Background Challenge 00:15: It tells us that the universe was once most certainly much smaller, hotter, and denser than it is today.
	2016-03-02: What’s Wrong With the Big Bang Theory? 12:21: The Big Bang describes a series of events that happened to the universe following its existence in an extremely hot, dense state. 00:41: Direct and convincing evidence tells us that the universe was once much smaller, hotter, and denser than it is now.
	2016-02-24: Why the Big Bang Definitely Happened 01:04: ... descriptions detailing the expansion of the universe from a tiny, super dense, super hot speck to the enormous cosmos that we know ... 03:34: One such prediction is that the entire universe was once as hot and dense and opaque as the inside of a star. 01:04: ... descriptions detailing the expansion of the universe from a tiny, super dense, super hot speck to the enormous cosmos that we know ... 04:38: ... to explain without a universe that was once much smaller, hotter, and denser. ...
	2016-02-11: LIGO's First Detection of Gravitational Waves! 02:25: These super dense objects produce serious gravitational radiation.
	2015-12-09: How to Build a Black Hole 02:09: The collapsing outer shells ricochet off this impossibly dense nugget in a supernova explosion, enriching the galaxy with juicy new elements. 06:55: And here's the thing-- the denser the neutron star becomes, the more momentum space you get. 06:23: So a neutron star is comprised of the densest matter in the universe.
	2015-08-27: Watch THIS! (New Host + Challenge Winners) 01:26: This is kind of a coincidence of the specific situation of a uniformly dense planet and Newtonian mechanics. 01:46: You have to do the algebra in this case, because this is very specific to the situation of a uniformly dense planet. 01:26: This is kind of a coincidence of the specific situation of a uniformly dense planet and Newtonian mechanics. 01:46: You have to do the algebra in this case, because this is very specific to the situation of a uniformly dense planet.
	2015-08-19: Do Events Inside Black Holes Happen? 08:37: ... three, that all black holes are super dense-- this kind of depends on what you mean by "density." If you know that ... 08:50: For instance, the 4 million solar mass black hole at the center of the Milky Way is about as dense as water. 09:13: ... mean by "density." Maybe you mean that all black holes are infinitely dense because all the stuff that goes into the black hole collapses to an ...
	2015-08-12: Challenge: Which Particle Wins This Race? 01:26: But I think it's easier to pretend that the planet is a uniformly dense fluid, and that this particle can pass through that fluid without friction.
	2015-06-17: How to Signal Aliens 09:51: Now, how do you reconcile this with the fact that helium is still less dense than air? 10:02: ... get less dense as you rise in the opposite direction of a gravitational field, because ...
	2015-06-03: Is Gravity An Illusion? 04:26: ... denser there, so the balloon is just trying to go toward the less dense air near the ... 04:57: The pendulum hangs down and the balloon aims up because air is denser on the ground and less dense at higher altitudes. 04:26: ... denser there, so the balloon is just trying to go toward the less dense air near the ... 04:57: The pendulum hangs down and the balloon aims up because air is denser on the ground and less dense at higher altitudes.
	2015-04-01: Is the Moon in Majora’s Mask a Black Hole? 02:09: OK, so how dense is Termina's moon? 04:00: ... Termina's moon really were only as dense as Earth's moon, its tidal force when hovering just above the planet's ... 04:57: The only solid macroscopic objects in nature that are that dense are neutron stars. 05:03: Those objects could only get that dense in the first place because of their immense self-gravity. 05:32: So if it's not a neutron star, how can Majora's moon be so dense? 05:50: So to serve as a gravitational seed, we need something incredibly small and incredibly dense, even denser than a neutron star. 04:22: ... moon to be-- wait for it-- between a billion and 100 trillion times denser than Earth's moon, depending on whether you think the tidal force is ... 05:39: ... you could somehow put a much denser mass at the center, the material around it might have enough of a ... 05:50: So to serve as a gravitational seed, we need something incredibly small and incredibly dense, even denser than a neutron star. 05:39: ... you could somehow put a much denser mass at the center, the material around it might have enough of a ...
	2015-03-18: Can A Starfox Barrel Roll Work In Space? 05:33: ... I can't tell you how massive or dense the gyros would need to be, whether you'd flip them mechanics or with ...
	2015-03-04: Should We Colonize Venus Instead of Mars? 04:45: ... at that altitude, the atmosphere is still dense enough for lots of stuff to floae-- like balloons filled with helium or ...

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