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

  • 04:36: ... cluster. If the alignment is close enough, we can see an Einstein Ring, like this   galaxy being lensed by an intervening galaxy. The ...
  • 10:07: ... units,   and extending indefinitely, with the Einstein ring getting wider and more diffuse the further you go.   The column for an ...

2022-06-30: Could We Decode Alien Physics?

  • 16:39: ... didn’t get to it 60 years earlier, Tony  - the Tee Jet has a nice ring to it.    Regarding shielding against interstellar ...

2022-06-01: What If Physics IS NOT Describing Reality?

  • 14:22: ... The  galactic habitable zone is defined to be a   ring around the disk, not too close to the core  and not too far out. It ...

2022-05-04: Space DOES NOT Expand Everywhere

  • 07:12: ... Lose another dimension of space so the universe becomes an expanding ring instead of a ,sphere, with grid points instead of gridlines. But then we ...
  • 07:58: ... galaxy causes gridlines to be pulled together on a sphere, then on the ring it causes points to be pulled together, and they maintain that ...
  • 09:38: ... the present and define a grid of space - or a grid of points on our 1-D ring universe. Then we rewind the universe and every single one of those ...

2022-02-23: Are Cosmic Strings Cracks in the Universe?

  • 00:58: ... - a pair of field strengths, and so   the new minimum formed a ring around the old minimum,  resembling an item of festive Mexican ...
  • 10:09: ... them  towards us. We can see multiple images or even a   ring surrounding that lens. A cosmic string would also deflect light ...

2021-12-29: How to Find ALIEN Dyson Spheres

  • 06:03: Partial Dyson spheres could take the form of equatorial rings of collectors, or swarms that don’t fill the entire spherical surface.

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

  • 18:16: ... may be that the so-called ring-down - the waves produced as the merged object settles back into a spheroid - ...

2021-11-17: Are Black Holes Actually Fuzzballs?

  • 06:01: ... a black hole’s mass into a single point, it gets distributed around the ring structure of these ...

2021-08-18: How Vacuum Decay Would Destroy The Universe

  • 01:31: ... at every point. As a   simplistic example, imagine a rubber ring at each point. If you compress the ring in one ...
  • 02:18: ... like the deformed ring, a quantum field  wants to return to its equilibrium ...

2021-07-21: How Magnetism Shapes The Universe

  • 10:59: If you thought the 27 km ring of the large hadron collider was big, try the 300,000 light year ring around the Milky Way.

2021-06-09: Are We Running Out of Space Above Earth?

  • 08:08: They quickly smear out in a ring around the Earth, making tracking and avoidance that much more difficult.

2021-04-21: The NEW Warp Drive Possibilities

  • 09:45: ... is in front and behind the spaceship, while the exotic matter is in a ring around the direction of ...

2021-03-16: The NEW Crisis in Cosmology

  • 10:08: ... already talked about one of these options. It’s to look for vast ring-like patterns in the   way galaxies are scattered across the ...

2021-02-17: Gravitational Wave Background Discovered?

  • 00:00: ... in what is known as a quadrupole wave if the wave passes through a ring of points those points would move in and out like this okay so imagine ...

2021-02-10: How Does Gravity Warp the Flow of Time?

  • 06:05: But first, let’s try this - build our lab into a giant, ring-shaped space station.

2020-12-15: The Supernova At The End of Time

  • 14:35: John Ring correctly summarizes that observers in a reverse-time universe wouldn't know the difference.

2020-10-27: How The Penrose Singularity Theorem Predicts The End of Space Time

  • 03:18: ... central point of infinite gravity is spun out into a   ring - but it was a singularity nonetheless. The Kerr solution was still ...
  • 08:49: ... central singularity, while in Kerr  black holes space ends at the ring ...

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

  • 00:28: ... will accelerate particles in a 100 kilometer circumference underground ring encircling ...
  • 02:29: The key to doing this is to store the particle beams in a ring so that they can be collided at your leisure.
  • 02:37: To that end, the particle storage ring was invented by Gerard K. O’Neill in the mid 1950s.
  • 02:53: Its four meter ring collided electrons and positrons.
  • 03:40: Graduating from electrons and positrons, in 1971 physicists started smashing protons together at CERN’s Intersecting Storage Rings facility.
  • 04:29: km circumference ring beneath the Swiss and French countrysides.
  • 14:49: Think of the case of the rotating black hole - the singularity is a ring, and relatively few geodesics - free-falling paths - hit the singularity.
  • 14:57: Most pass through the ring.

2020-08-17: How Stars Destroy Each Other

  • 08:29: That gas forms an enveloping ring around the whole system, which then falls onto the neutron star.

2020-07-08: Does Antimatter Explain Why There's Something Rather Than Nothing?

  • 08:00: ... around the outside of the chamber direct the anti-protons to a storage ring called the Antiproton Decelerator, where they are slowed down by pulses ...

2020-06-30: Dissolving an Event Horizon

  • 02:57: Inside, we found that the rapid rotation has spun the point-like singularity into a ring of infinite density.
  • 03:04: The time machine is on the other side of that ring, by the way.
  • 03:09: The same rotation that f orms the ring also drags the fabric of space into a vortex which counters the inward pull due to the singularity’s mass.
  • 03:51: Instead, there’s a smooth run of normal - albeit rapidly spinning space all the way down to the singularity ring.
  • 04:00: The NAKED singularity ring.
  • 12:20: Each ring you pass as you go down that funnel represents crossing 3-D spherical shell.

2020-06-15: What Happens After the Universe Ends?

  • 13:28: Penroses proposes that the collisions of super massive black holes in the previous universe may leave rings on the sky in the next.

2020-05-18: Mapping the Multiverse

  • 04:54: The singular, central point has been spun out into a ring of infinite density.
  • 05:14: ... through the inner horizon, or you can plunge through the singularity ring. ...
  • 06:24: But within a Kerr black hole, the singularity is a ring, and the trillion balls would fall towards the disk bounded by that ring.
  • 06:33: Only the ones exactly on the equator hit the ring and, those geodesics do end - same infinite squish as in a Schwarzschild black hole.
  • 06:58: Before we take that outward ride, let’s push a little harder and try to get through the ring.
  • 07:04: With a lot of speed - and I mean a LOT - it’s possible to overcome the anti-gravitational field in the middle of the ring and punch through.
  • 07:17: ... ring is like a portal to a new, very different region of spacetime - and ...
  • 07:34: For one thing, the ring singularity becomes entirely repulsive - as though it had negative mass.
  • 07:50: For one thing, the lack of event horizons above you means the ring is a naked singularity, as well as being repulsive.
  • 07:58: Surrounding the ring on this side is a toroidal region in which it’s possible to accelerate to infinite speed.
  • 08:43: We’ll come back to how it can be avoided in the math - for now, let’s whip once around back to our own past and hop back through the ring.
  • 09:39: Extending the Kerr metric from ring singularity into the future leads to something else.
  • 13:35: They just don’t have the ring singularity leading to the bizarro-verse, so Kerr is more fun than Reissner-Nordström.

2020-04-28: Space Time Livestream: Ask Matt Anything

  • 00:00: ... telescope okay so it's a 10 inch Dobsonian you can see the I mean the rings of Saturn are amazing with that telescope it's also a plan holder by ...

2020-04-22: Will Wormholes Allow Fast Interstellar Travel?

  • 03:45: ... time frozen for the moment and add back the 3rd spatial dimension. The ring of the wormhole is actually a sphere the size of the Schwarzschild event ...

2020-01-06: How To Detect a Neutrino

  • 02:47: ... beam line accelerates protons around a two and a half mile circumference ring, using giant electromagnets, ♪ (𝘳𝘩𝘺𝘵𝘩𝘮 𝘣𝘶𝘪𝘭𝘥𝘴) ♪ to around 99.997% the ...

2019-10-15: Loop Quantum Gravity Explained

  • 15:49: ... universe - or in the case of a rotating black hole, an infinite density ring. ...
  • 17:07: Especially given that I kept saying a struck black hole rings like a bell.

2019-10-07: Black Hole Harmonics

  • 02:37: This final phase is called the ring-down – an expression comes from the analogy with a bell.
  • 02:48: As those vibrations give up their energy – in this case to sound waves – the vibrations fade. The bell rings down.
  • 04:39: OK, so a black hole can ring like a bell when struck – in that case a black hole merger is the biggest hammer strike of all.
  • 04:46: But what does the ring-down of a black hole really look like?
  • 04:57: ... in order to see the overtones you’d need to look at the tail end of the ring-down, when the black hole was approaching a more spherical ...
  • 05:20: The problem is, at the tail-end of the ring-down the LIGO signals are probably too weak to detect the overtones.
  • 05:37: They looked for overtones in the ring-down from right at the point of black hole merger.
  • 06:45: ... when the ringdown begins some of the overtones are actually stronger than the fundamental ...
  • 07:12: Similarly, the overtone structure of a black hole ringdown can identify the fundamental properties of that black hole – namely its mass and spin.
  • 08:04: looked at the merger and ring-down signal from the largest black hole merger we’ve seen.
  • 08:22: ... team analyzed the harmonics in the gravitational wave ring-down from this event and claim a likely detection of at least one overtone – ...
  • 09:13: ... the mass and spin derived from the ringdown are consistent with the estimate that was previously obtained by ...
  • 09:24: ... is important, because the overtone analysis ONLY looked at the ringdown, so this tells us that all information on the nature of the final black ...
  • 10:08: ... define everything – including the nature of the oscillations during ring-down. ...
  • 12:59: ... gravitational wave spectroscopy, we can now listen to the harmonics of ringing black holes, and through them better understand the fundamental nature ...

2019-09-03: Is Earth's Magnetic Field Reversing?

  • 06:21: As a result, the starting magnetic field gets wound up into rings around the axis of rotation – into a torus shape.
  • 06:56: Now we have exactly the conditions of an electromagnet – organized rings of current, which produce our giant dipole field.

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

  • 16:21: ... can't actually see the event horizon telescope" doesn't have such a nice ring to ...
  • 16:53: Belodri writes from Austria to inform us that their phone ring is now me saying Zwicky.

2019-05-01: The Real Science of the EHT Black Hole

  • 06:17: What we’re seeing here is the black hole shadow inside the bright ring of the photon sphere.
  • 06:36: We only see light that escapes directly towards us, so the photon sphere looks like a photon ring.
  • 08:14: The ring is the photon sphere, blurred due to the fact that this observation is incredibly difficult and the EHT is “only” the size of the Earth.
  • 08:24: In principle this could be a very narrow ring.
  • 10:01: ... asymmetry in the ring tells us the rotational direction of the vortex, so combine that with ...

2019-03-06: The Impossibility of Perpetual Motion Machines

  • 15:07: ... the baryon acoustic oscillations frozen into both the CMB and in galaxy rings were blurred out quite a bit because the universe took a moment to ...

2019-02-20: Secrets of the Cosmic Microwave Background

  • 02:05: ... collapsed into galaxies We still see them today Interwoven patterns of rings drawn in galaxies on the sky but those rings are not the whole story ...
  • 14:23: ... oscillations should have produced bubbles, spheres rather than rings on the sky That's right, they definitely would have produced 3D ...

2019-02-07: Sound Waves from the Beginning of Time

  • 07:09: So those rings should be 150 mega parsecs across, 500 million light years.
  • 07:22: Well, crazily, we can still see those rings, not made of plasma or gas, but made of galaxies.
  • 08:27: Those rings were further smeared out over the thousands of years it took for the universe to fully transition from plasma to gas.
  • 09:46: Corresponding to the acoustic rings, everything is so hopelessly overlapping.
  • 10:21: These are the galaxy pairs where one is at the center of the dark matter peak, and one is on the surrounding ring.
  • 11:26: See, we know exactly how big those acoustic rings should be.
  • 11:47: ... means we know how big those rings were when they formed, and we can see how big they are at different ...
  • 11:57: These rings give us a standard ruler on the sky, spanning all of cosmic time.
  • 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.

2018-10-18: What are the Strings in String Theory?

  • 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.

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

  • 12:45: You could also check Appendix F in Lord of the Rings.

2018-01-17: Horizon Radiation

  • 12:56: Extremely large quakes can set the entire star ringing, which is observable in its effect on the extremely regular flashes of its pulsar jet.

2018-01-10: What Do Stars Sound Like?

  • 01:44: Stars ring like bells.
  • 03:45: ... just as a single tap can set an entire bell ringing, a single traveling wave feeds its energy into standing pressure waves ...

2017-11-22: Suicide Space Robots

  • 04:47: This orbiter studied Saturn and its moons and rings for 13 years.

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

  • 05:22: They have magnetic fields, just like a little bar magnet, or electric currents rotating in a ring even though there is no actual rotation.
  • 13:41: ... to build something like an aragoscope with infinitely many concentric rings by using some sort of advanced diffracting ...
  • 14:02: To do something similar with visible light, you'd need a nanofabricated structure with actual concentric rings.
  • 14:09: ... problem then is that the focal length of the rings depends on their size, with smaller rings creating a focus closer to the ...
  • 14:18: So this material would have to be cone-shaped so the smaller rings are closer to the detector.

2017-09-20: The Future of Space Telescopes

  • 07:00: All you get is the thin ring of light diffracted around the edge.
  • 07:20: It's also possible to break the disk into a set of concentric rings so that you get many diffraction edges.
  • 07:27: There are challenges to bring the light from each ring to the same focus, but fortunately humans are pretty smart and there are ways to do this.
  • 13:14: [INAUDIBLE] wants to confirm that the gold in their ring may have been created in the collision of two neutron stars.
  • 13:29: So yeah, your ring was forged in the death of a star or the birth of a black hole.

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

  • 05:37: ... hit that range in the final second before merger, while neutron stars ring at audible gravitational wave frequencies for at least several ...

2017-05-10: The Great American Eclipse

  • 04:23: Such eclipses are called annular eclipses, because they leave a ring of bright sunlight around the moon's disk.
  • 05:43: The sun's final crescent contracts to a last spark on one side of the moon, like a diamond ring.
  • 07:40: Bailey's beads and the red chromosphere flash along the edge of the moon, the diamond ring emerging on the Western side.

2017-04-19: The Oh My God Particle

  • 06:00: We build artificial ones on Earth using giant rings and powerful magnetic fields.

2017-03-15: Time Crystals!

  • 02:01: Wilczek came up with a simple model in which charged particles in a superconducting ring break what we call continuous time translational symmetry.

2017-02-22: The Eye of Sauron Reveals a Forming Solar System!

  • 01:26: But the surrounding ring is very real.
  • 01:35: But the ring is brightest in the infrared.
  • 01:46: We're seeing the heat glow of a giant ring of ice and dust 40 billion kilometers in diameter.
  • 04:38: The Herschel and Alma images show very clearly that the ring has sharp edges, particularly that inner edge.
  • 04:45: The leading idea is that newly formed planets carved out that ring with their gravity.
  • 04:50: Check out Saturn's F ring.
  • 05:22: So a planet passing along the inside of the dust ring overtakes each grain of dust and tugs them gently forward.
  • 05:37: A planet passing along the outside of the dust ring pulls back on the dust.
  • 05:47: Pushed outwards and inwards by the Shepherd planets, the dust ring boundaries sharpen between them.
  • 06:07: In fact, it is very possible that we've actually found the planet that carves out the inner edge of that ring.
  • 06:37: Or even cooler, it may be a planet with a giant reflective ring system.
  • 06:42: If so, Fomalhaut really does seem to have a thing for rings.
  • 09:10: The fiery eye of Sauron, wielding rings within rings.

2017-01-25: Why Quasars are so Awesome

  • 05:23: But viewed side on, that disk is obscured by a thick ring of dusty gas.

2016-11-09: Did Dark Energy Just Disappear?

  • 14:03: My point is that there are plausible options, and a giant rotating maglev ring city in a sealed taurus is actually plausible.

2016-10-19: The First Humans on Mars

  • 06:02: This is possible using a centrifuge, a rotating ring that results in the feeling of an outward force, a centrifugal force, with respect to the ring.
  • 06:19: ... would still involve a large rotating ring, but with a sloped, slightly curved outer wall so that the centrifugal ...

2016-09-29: Life on Europa?

  • 02:25: Its geysers actually produce one of Saturn's rings.
  • 02:29: And the Cassini spacecraft found that ring to contain salt.

2016-07-06: Juno to Reveal Jupiter's Violent Past

  • 02:23: In the wake of its intense gravitational field, it drags with it its own mini solar system of at least 67 moons and a faint ring system.

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

  • 11:42: OK, a lot of you wanted to know why it is that the Einstein cross is a cross rather than a full ring.
  • 12:05: We call that an Einstein ring.
  • 13:01: Then you'll see an Einstein ring.
  • 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

  • 03:30: ... they are greatly magnified in brightness and stretched into arcs and rings. ...
  • 08:46: ... light from any surrounding whirlpool of hot plasma to form a bright ring around the black ...

2016-06-08: New Fundamental Particle Discovered?? + Challenge Winners!

  • 01:03: A ring of gigantic magnets accelerates protons to up to 0.99999999 of the speed of light before colliding them from opposite directions.

2016-04-06: We Are Star Stuff

  • 08:27: ... gold in your ring, the nickel in your nickel, and, in fact, a lot of the iron in your ...

2016-02-24: Why the Big Bang Definitely Happened

  • 06:21: The fancy name is baryon acoustic oscillations which cause ring-like clustering of the CMB fluctuations.

2016-02-11: LIGO's First Detection of Gravitational Waves!

  • 06:48: ... see the slow ringing of binary white dwarf stars in our own galaxy, as well as the final ...

2015-12-09: How to Build a Black Hole

  • 12:28: Sam Gilfellan wants know how large an object we'd need to destroy in order to form a ring system around the earth.
  • 12:35: ... if we want a ring system like Sam's, that has the same ratio of planet mass to ring mass-- ...
  • 12:54: A ring system around the earth would be awesome.

2015-10-28: Is The Alcubierre Warp Drive Possible?

  • 03:24: ... try to do this for the warp field, you find that you need to produce a ring of negative energy density in a band around the ship to produce the ...

2015-05-06: Should the First Mars Mission Be All Women?

  • 08:52: ... why we didn't bring up gravity gradient effects, namely that in a small ring-- this is not as a big a problem in large rings-- there would be a gravity ...

2015-04-29: What's the Most Realistic Artificial Gravity in Sci-Fi?

  • 02:49: ... as we gut check the physics of the following sci-fi examples-- "2001," "Ringworld," "Halo," and "Babylon 5"-- all which use rotation-induced artificial ...
  • 03:17: ... surface or 10 meters per second squared, our earlier formula says the ring would need to rotate at 1.1 radians per ...
  • 04:08: In this case, we're talking about the ring.
  • 04:21: If he's actually running against the ring's rotation, he would tend to curve upward and could levitate just by sprinting, instead of jogging.
  • 05:11: You can minimize these problems with a bigger ring, since that'll require less rotation to get the same 1 g of surface gravity.
  • 05:17: ... let's look at an extreme example of a big ring, Larry Niven's "Ringworld." The ring habitat in that novel has the same ...
  • 05:31: ... achieve 1 g, Ringworld's rotational velocity would be small enough that, just like on Earth, ...
  • 05:38: And to Niven's credit, he also correctly had hurricanes on Ringworld rotate vertically because the deflections would go like this.
  • 05:48: But Ringworld has a different problem, namely composition.
  • 05:51: To sustain 1 g, the ring would need to complete the equivalent of one Earth orbit around the sun in only nine days.
  • 05:57: That's slow for Coriolis purposes, but it's really fast in terms of mechanical stresses in the ring.
  • 06:12: But if you go too big, the mechanical stresses will destroy your ring.
  • 06:16: So do any franchises have a ring size that finds a good balance between these two?
  • 07:12: ... space station on "Babylon 5." The key is that "Babylon 5" abandons the ring shape altogether and makes a cylinder instead, one about 8 kilometers ...
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