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	2022-08-03: What Happens Inside a Proton? 11:28: ... dimension of space.   This operation is called the Wick rotation and it eliminates the complex nature of the phase ...
	2022-04-27: How the Higgs Mechanism Give Things Mass 03:09: ... can be represented with just   “one” number in this case rotation of  phase angle vector of “unit” ... 09:34: ... We need the laws of physics  to still make sense if there are rotations from   one point in space to the next. That means  adding ... 11:02: ... The new state of the field  would not be symmetric to the same rotations,   because different points around this valley  correspond to ...
	2022-03-08: Is the Proxima System Our Best Hope For Another Earth? 09:17: ... the star means strong tidal forces, which will have forced the planet’s rotation period to be in resonance with its orbital ...
	2022-02-23: Are Cosmic Strings Cracks in the Universe? 05:59: ... is for them to vary smoothly around a loop - a   2-pi rotation of the phase angle around the  intersection. And that left a knot ...
	2021-11-10: What If Our Understanding of Gravity Is Wrong? 01:22: The expected rotation rates of galaxies come  from applying our laws of gravity based on the observed mass. 02:25: The so-called rotation curve should drop - orbital  speed should diminish with distance from center. 02:32: ... the gravitational field in the outskirts to explain the high rotation ... 02:43: Dark matter flattens rotation curves. 04:08: If you tune the modification right you recover  the observed rotation curves for spiral galaxies very nicely without the need for extra mass. 04:17: ... which is effectively the minimum acceleration - to get the correct rotation curves for nearly all ... 06:35: ... galaxies all follow this tight relationship  between their speed of rotation and their luminosity - the brighter they are the faster they ... 06:47: ... that the Tully-Fisher Law  is such a tight relationship because the rotation velocity depends on the dark matter halo  while the luminosity ... 07:05: ... the other hand, if you tune MOND to get the flat rotation curves of spiral galaxies, you automatically get the correct ... 13:10: ... the phenomena that MOND  predicts naturally - like the flatness of rotation curves and the Tully-Fisher ...
	2021-10-13: New Results in Quantum Tunneling vs. The Speed of Light 10:59: The rate of rotation can be used as an internal clock.
	2021-10-05: Why Magnetic Monopoles SHOULD Exist 17:28: USB plugs have spin 2/3s - a 360 degree rotation gets you 2/3 of the way around. 17:40: ... remember that you can undo fermion rotations by translation of the ends - for USB cables its the opposite- twists ...
	2021-09-21: How Electron Spin Makes Matter Possible 00:26: ... to its starting position. They are, we say, spin-½ - because one normal rotation only gets you halfway around. That particular weirdness is not just ... 01:13: ... for example is the much more sensible case of a single 360 degrees rotation back to the starting point. Integer-spin particles are bosons, and they ... 02:18: ... behavior of groups of particles that have two properties: 1) this weird rotational symmetry, and 2) indistinguishability - which is just the fact that all ... 02:59: ... this property that it returns to its starting state with a 720 degree rotation, not ... 03:19: ... Crazily the bands disentangle every 720 degrees. So a spinor’s rotational weirdness is not necessarily all that “quantum” - it’s a natural ... 03:46: ... there you go, the twists are gone. So the system under these sorts of rotations is a spinor because a 720 twist is topologically equivalent to no twist ... 04:43: ... the belt ends up with a single twist in it - equivalent to a 360 degree rotation of one end. So it seems that for spinors, a 360 degree rotation is ... 05:33: ... what we’ve learned. There are objects that require a 720 degree rotation to return to their original configuration in terms of their relationship ... 05:44: ... these things spinors. For these same objects - spinors - a 360 degree rotation is the same thing as swapping places with a second spinor, at least in ... 06:49: ... can “wave” through space, but it includes another wavy part. It has its rotational degree of freedom in which a full wave cycle is a 720 degree rotation. ... 07:22: ... so summarizing again: Electrons are spinors and so require a 720 degree rotation to be returned to their initial state. But a 360 degree rotation shifts ... 14:26: ... because electrons are indistinguishable and they obey a simple, if odd, rotational symmetry. Ironically, to prove the structural integrity of matter I had ...
	2021-09-15: Neutron Stars: The Most Extreme Objects in the Universe 10:06: ... exactly one frequency- twice the  frequency of the neutron star’s rotation-   and gravitational wave astronomers are searching for these signals ...
	2021-09-07: First Detection of Light from Behind a Black Hole 11:18: We have other reasons to think that this iron-laced wind also has a powerful rotational component.
	2021-08-10: How to Communicate Across the Quantum Multiverse 14:02: ... rule out that this white dwarf got its weird properties like its rapid rotation from being the result of a merger, rather than being a more usual white ... 14:53: ... post-common envelope close binary systems - V471 Tauri with its 7 minute rotation being a good example. For those non-white-dwarf-astrophysicists out ...
	2021-07-21: How Magnetism Shapes The Universe 04:05: But the Sun is entirely fluid, and its rate of rotation speeds up towards the equator. 07:43: ... can be left- or right-polarized, meaning clockwise or counterclockwise rotation. ... 08:02: ... of the circular polarizations - gets rotated in an effect called Faraday rotation. ... 08:12: So by measuring the Faraday rotation of distant radio sources we can also map magnetic fields. 09:21: ... but the ingredients for a dynamo are all there: we have differential rotation in the disk which can lead to coriolis-induced helical flows, and those ... 09:53: Magnetic fields generated by collapsing gas clouds help to slow the rotation of those clouds - expel angular momentum.
	2021-07-07: Electrons DO NOT Spin 00:47: ... bicycle wheels, and their shifted angular momenta is compensated by the rotation of the ... 01:26: ... strange type of angular momentum that somehow exists without classical rotation. In fact the spin of an electron is far more fundamental than simple ... 03:48: ... the idea of associating such   a classical property like rotation to the electron, instead insisting on calling it a “classically ... 07:02: ... not only do electrons have this magnetic  moment without rotation, but the direction of the underlying magnetic  momentum is ... 08:50: ... to give you a taste. They describe particles that have very strange rotation properties. For familiar  objects, a rotation of 360 degrees gets ... 09:20: Here’s an example of spinor-like behavior. If I rotate this mug without letting go my arm gets a twist. A second rotation untwists me. 09:59: ... to  all other points in the universe by invisible strands. One rotation causes a twist, two brings it back to normal. To get a little more ... 11:09: ... about the  angular momentum of an electron is not from classical rotation,   but rather from the fact that they  have a rotational degree of ... 12:13: ... but instead by vectors, and behave  more intuitively - a 360 degree rotation brings them back to their original ... 12:44: ... difference in the rotational  properties of fermions and bosons   results in profound ... 13:00: ... you don’t fall through the floor right now. But why should this obscure rotational property lead to such fundamental behavior? Well this  is all part ...
	2021-06-23: How Quantum Entanglement Creates Entropy 16:39: ... space. But we know for sure that this universe has a continuous rotational symmetry - there   is no preferred angle. That’s the basis for ...
	2021-04-07: Why the Muon g-2 Results Are So Exciting! 03:12: This isn't the same thing as simple rotation. 03:37: The strength of that rotational pool or the talk, is defined by the objects dipole moment. 03:43: For a rotating charge, that depends on the objects rate of rotation, or angular momentum, it's charge and it's mass.
	2021-02-17: Gravitational Wave Background Discovered? 00:00: ... due to their intense magnetic fields they also rotate rapidly with the rotational axis offset from the magnetic poles causing those jets to sweep through ...
	2021-01-26: Is Dark Matter Made of Particles? 03:45: ... can map where dark matter is found by how it affects the rotation of galaxies, and how it drives the orbits of galaxies inside galaxy ...
	2020-12-22: Navigating with Quantum Entanglement 04:12: This “declination” points towards the magnetic poles, which are offset from the true poles defined by Earth’s rotational axis.
	2020-11-04: Electroweak Theory and the Origin of the Fundamental Forces 06:20: ... the length of the vector is the magnitude of the wavefunction, and the rotation amount is our local phase ... 06:38: The collection of transformations which are just rotations of 2D vectors are members of something called the Unitary group of size 1, written U(1).
	2020-07-20: The Boundary Between Black Holes & Neutron Stars 12:18: ... we talked about how to dissolve a black hole event horizon by adding rotation or charge to the black hole, and also about experiments at CERN to study ...
	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. 03:09: 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. 03:40: At a certain very high rotation rate, the inner and outer horizons merge - which means they both vanish. 04:02: There’s a similar situation with the charged black hole - which, absent rotation, is described by the Reisner-Nordstrom metric.
	2020-06-22: Building Black Holes in a Lab 08:04: ... thing we saw was that rotating black holes can donate some of their rotational energy to particles or waves that pass close by. This is the Penrose ... 08:42: ... of fluorescent water.. Water pours in from two sides, creating a slow rotation that eventually spins into a carefully shaped funnel, forming a ...
	2020-05-27: Does Gravity Require Extra Dimensions? 08:55: ... the torsion pendulum ever so slightly, and by reading off the amount of rotation Cavendish made the first measurement of the gravitational ...
	2020-05-18: Mapping the Multiverse 01:59: Let’s think about what that rotation does in familiar terms. 02:16: Well, in a Kerr black hole that rotation results in an outward pressure that partially counteracts the inward flow due to gravity. 04:06: But now as we fall the outward pressure due to the black hole’s rotation starts to win against that inward flow. 05:00: It’s surrounded by a second ergosphere, where again the rotational flow of space exceeds light speed. 13:26: That resists the inward flow just like rotation does in a Kerr black hole.
	2020-04-28: Space Time Livestream: Ask Matt Anything 00:00: ... the interpretations of quantum mechanics and the the Vigna von Neumann rotation requires an observer you know of course the both the Dubrow Bohm and ...
	2020-03-31: What’s On The Other Side Of A Black Hole? 13:31: ... better animations. But how big is the bomb? Well the limit is as much rotational energy as the black hole contains. for a maximally rotating black hole ...
	2020-03-24: How Black Holes Spin Space Time 01:01: ... solution. That’s because the Schwarzschild black hole has no rotation. But all real, astrophysical black holes are ... 01:44: ... momentum of everything that went into forming it. That includes the rotation of the star’s core that collapsed into the black hole in the first ... 02:26: ... fall in with different spins or in different directions. But some rotation is always ... 02:36: ... the Kerr metric and describing the Kerr black hole, which has mass and rotation but no ... 03:54: ... But if nothing can escape the event horizon, how can that internal rotation influence the ... 04:11: ... fact it sort of doesn’t actually. Both the gravitational field and its rotation can be thought of as properties of the spacetime ... 09:37: ... energy is extracted from the rotational energy in the ergosphere, slowing the black hole’s spin. To get a little ... 10:11: ... light. Light that is directed through the ergosphere in the direction of rotation will also extract rotational energy and emerge amplified in a process ... 10:27: ... way the rotational energy can be extracted with, in principle, 100% efficiency. Oh, and you ... 10:51: ... light. Ultimately, the energy of that light is extracted from the rotational energy of the black hole. It’s hypothesized that some jets observed from ... 11:31: ... and spit it back out in powerful jets, again powered by the black hole’s rotation. If we happen to be along the paths of one of these jets, relativistic ...
	2019-11-04: Why We Might Be Alone in the Universe 07:43: That impact likely gave Earth its rapid rotation rate - with short nights essential for photosynthesis, and also its axial tilt.
	2019-10-15: Loop Quantum Gravity Explained 07:52: And the amount of rotation encodes information about the changes in geometry along the path. 15:35: ... there's a limit to the rotation of a black hole which comes from the fact that the outward centrifugal ... 16:02: ... singularities are expected to be impossible, and so we expect a maximum rotation rate for black holes. The details of all this need their own episode, so ...
	2019-09-03: Is Earth's Magnetic Field Reversing? 04:33: ... day is a few seconds shorter than a surface day. The outer core has a rotation gradient – the outer layer actually rotates a bit slower than the ... 06:16: But remember that the rotation of the outer core gets faster towards the center. 06:21: As a result, the starting magnetic field gets wound up into rings around the axis of rotation – into a torus shape. 06:47: Those loops form magnetic tubes around Earth’s rotational axis. 07:54: The north and south gomagnetic poles are close to the geographic poles – so, close to Earth’s rotation axis, but are not quite exactly aligned.
	2019-07-01: Thorium and the Future of Nuclear Energy 17:49: ... objects orbit in the same direction as a black hole's rotation that can be stable much closer in but if they orbit in the opposite ...
	2019-05-01: The Real Science of the EHT Black Hole 09:19: ... black hole mass and spin rate, while they were able to nail down the rotational axis rotation based on the jet that we see leaving the ... 10:01: ... asymmetry in the ring tells us the rotational direction of the vortex, so combine that with the axis direction from ...
	2019-04-24: No Dark Matter = Proof of Dark Matter? 00:03: ... began in earnest after the early 70s when Vera Rubin discovered that the rotation rates of spiral galaxies were too fast given the mass of their visible ...
	2019-03-20: Is Dark Energy Getting Stronger? 02:32: We see its effect in the rotation and movement of galaxies and in the bending of light due its space-warping gravity.
	2019-03-13: Will You Travel to Space? 14:38: ... Even in a vacuum, that internal vibration is enough to randomize its rotational ...
	2019-03-06: The Impossibility of Perpetual Motion Machines 04:05: When one hits the wheel in one direction the cog turns, but in the other direction the rotation is blocked.
	2019-01-09: Are Dark Matter And Dark Energy The Same? 12:41: Those galaxy rotation simulations are fascinating.
	2018-12-20: Why String Theory is Wrong 04:07: Momentum in that loop dimension has the exact behavior of electric charge, with the direction of rotation determining the sign of the charge.
	2018-12-12: Quantum Physics in a Mirror Universe 00:02: ... stays the same this is exactly the same as a z-axis reflection plus a rotation in fact a reflection on any single axis can be reproduced by a ...
	2018-11-21: 'Oumuamua Is Not Aliens 08:16: ... paper, adding that perhaps it broke itself apart due to its rapid rotation before ...
	2018-09-20: Quantum Gravity and the Hardest Problem in Physics 14:12: And the incoming object absorbs some of that rotational energy and get flung out at a higher speed. 14:18: The loss of rotational energy by the black hole also means a loss of mass.
	2018-09-05: The Black Hole Entropy Enigma 06:29: There's also the Penrose process in which you can extract rotational energy of a spinning black hole.
	2018-08-30: Is There Life on Mars? 02:06: ... a dark patch on the Martian surface, and so measure Mars's 24-hour rotation rate, as well as a white spot on its south ...
	2018-08-15: Quantum Theory's Most Incredible Prediction 04:12: Despite not being the same as classical rotation, this quantum spin does grant electrons a dipole magnetic field.
	2018-07-04: Will A New Neutrino Change The Standard Model? 03:50: Helicity can be right-handed, which means clockwise rotation, or left-handed or anticlockwise. 04:04: It's related to the direction in which the particle's phase shifts under rotations.
	2018-06-13: What Survives Inside A Black Hole? 08:46: In a similar way, you can see a black hole's rotation in its gravitational field. 09:00: ... incredibly subtle frame dragging due to Earth's rotation has been detected, but it required the incredible precision and ...
	2018-05-16: Noether's Theorem and The Symmetries of Reality 02:23: Snowflakes are symmetric under 60-degree rotation-- playing cards under a 180-degree rotation. 02:29: But these are what we call discrete symmetries-- single flips around one axis or rotation by specific amounts. 02:53: A perfect sphere is continuously symmetric under rotational translations. 04:07: ... example, if the factors driving the laws of motion are symmetric under rotation-- for example, the spherically-symmetric gravitational field experienced ...
	2018-05-09: How Gaia Changed Astronomy Forever 05:22: We can see the rotation of the Milky Way through the red and blue Doppler shift of the stars.
	2018-03-28: The Andromeda-Milky Way Collision 04:40: Then they averaged the observed motion of all of those stars and removed the effects due to the rotation of Andromeda and the motion of the sun.
	2018-01-10: What Do Stars Sound Like? 05:48: The internal rotation of the star is also a key factor. 06:11: This differential rotation powers the sun's magnetic field and is also responsible for twisting that magnetic field to drive the sunspot cycle.
	2017-12-20: Extinction by Gamma-Ray Burst 07:48: The rotational axis of the star will define the direction of the jet in the event that this Wolf-Rayet star does produce a gamma-ray burst. 08:26: It's the star's rotational axis that defines the direction of the jet. 08:30: But the orbital axis of a binary system and the rotational axis of its stars are often correlated, so we may have dodged a bullet in this case.
	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.
	2017-08-16: Extraterrestrial Superstorms 02:34: The result is a raging vortex in the same direction as the Earth's rotation, clockwise in the southern hemisphere and counterclockwise in the north. 09:54: Turbulent flow acts like friction, sapping energy away from the bulk rotation.
	2017-05-17: Martian Evolution 14:08: venkata asks why the eclipse shadow moves from east to west rather than west to east as you might expect due to the rotation of the Earth.
	2017-05-10: The Great American Eclipse 04:40: Every year, the moon steals a little bit of Earth's rotational kinetic energy and drifts about 3.8 centimeters away from us.
	2017-04-05: Telescopes on the Moon 07:11: Pointing options are still limited, but by taking advantage of Earth or the moon's rotation, it's possible to scan a narrow arc across the sky.
	2017-02-22: The Eye of Sauron Reveals a Forming Solar System! 02:58: And that rotation allows it to resist falling towards the central axis.
	2016-12-14: Escape The Kugelblitz Challenge 01:11: The Penrose diagram we looked at represents a Schwarchild black hole-- so no electric charge and no rotation, but also an eternal black hole.
	2016-12-08: What Happens at the Event Horizon? 01:07: ... ignoring the complications of Hawking radiation or black hole rotational growth, the simplest black hole of Einstein's general theory of ...
	2016-11-30: Pilot Wave Theory and Quantum Realism 15:06: With their extreme rotation rates, neutron stars support electric currents sufficient for magnetic fields of up to 100 million tesla.
	2016-07-27: The Quantum Experiment that Broke Reality 11:58: It's called "the Jeans mass." It depends on cloud size, temperature, rotation rate, and composition.
	2016-03-30: Pulsar Starquakes Make Fast Radio Bursts? + Challenge Winners! 01:56: ... insane rates and occasionally give off extremely intense bursts as their rotation glitches and starquakes rock these intensely energetic ...
	2016-03-16: Why is the Earth Round and the Milky Way Flat? 07:55: ... the Equator the upward acceleration we feel due to the Earth's rotation is 0.03 meters per second squared, compared to 9.8 meters per second ... 09:10: This global rotation makes it even harder for the cloud to collapse. 09:14: The gas can't fall any closer to the axis of rotation because it's orbiting that axis.
	2015-08-19: Do Events Inside Black Holes Happen? 01:44: ... he tumbles on, I see his rotation rate become more slow motion, but I also see him pick up translational ...
	2015-08-05: What Physics Teachers Get Wrong About Tides! 08:36: So are other things that I haven't mentioned, like how the rate of Earth's rotation and the ocean tides affect each other.
	2015-07-08: The Leap Second Explained 00:00: [MUSIC PLAYING] In an earlier episode, we mentioned the Earth's rotation is slowing down. 00:10: Supposedly, leap seconds are related to this slowing rotation, but the math seems to be way off. 00:27: But Earth's rotation slows, so that's a bad definition. 01:47: Of course, Earth's rotation has irregularities due to earthquakes and other effects. 01:54: Now, over time, Earth's rotation will keep slowing and leap seconds will become more frequent.
	2015-07-02: Can a Circle Be a Straight Line? 09:40: ... or for instance, when you measure the rate at which the Earth slows its rotation. ...
	2015-06-24: The Calendar, Australia & White Christmas 04:28: The rotation axis wobbles. 05:58: Also, if you'd like to see an episode on what Earth's orbit and rotation really look like in space and why, let us know that, too.
	2015-06-03: Is Gravity An Illusion? 02:23: ... the tracks pretty much is inertial-- at least if you disregard Earth's rotation, because relative to that frame, you don't accelerate at ...
	2015-04-29: What's the Most Realistic Artificial Gravity in Sci-Fi? 01:29: All right, so how exactly does rotation simulate gravity? 02:33: It's just the radius of the rotating structure multiplied by the square of its rotational speed in radians per second. 02:38: ... you adjust the radius and rotation rate of the room, you can make that force from the wall on your feet ... 02:49: ... examples-- "2001," "Ringworld," "Halo," and "Babylon 5"-- all which use rotation-induced artificial ... 04:01: An object's Coriolis acceleration will be proportional to its speed, relative to the rotating frame and the rotation rate of the frame itself. 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. 04:57: ... concept of artificial gravity correct, given its small radius and high rotation rate, it ends up sweeping major Coriolis effect under the rug, ... 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. 05:31: ... achieve 1 g, Ringworld's rotational velocity would be small enough that, just like on Earth, Coriolis ... 06:38: And apparently, a halo at that size and rotation could actually stay mechanically intact. 07:46: ... 5" actually gets a lot of other qualitative things right about rotation-induced gravity, like the way that its fighter ships, the Starfurys, launch just ... 08:10: ... is I can't actually find anything that the game gets wrong per se in its rotational artificial ...
	2015-03-18: Can A Starfox Barrel Roll Work In Space? 01:14: ... of the forces on the wings and torquing the ship back to a state of zero rotation. ... 02:09: ... speaking, that narrow points along the axis of rotation, in the same direction that the thumb of your right hand would point if ... 05:29: I don't have any numbers on the mass and rotational inertia of a "Star Fox" Arwing.

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