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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 ...
  • 03:09: ... can be represented with just   “one” number in this case rotation of  phase angle vector of “unit” ...
  • 09:34: ... gauge field in the Lagrangian   that allows the angle of this rotational degree  of freedom to vary. Call that angle ...
  • 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 ...
  • 02:25: The so-called rotation curve should drop - orbital  speed should diminish with distance from center.
  • 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 ...
  • 07:05: ... the other hand, if you tune MOND to get the flat rotation curves of spiral galaxies, you automatically get the correct relationship  ...
  • 13:10: ... the phenomena that MOND  predicts naturally - like the flatness of rotation curves and the Tully-Fisher ...
  • 01:22: The expected rotation rates of galaxies come  from applying our laws of gravity based on the observed mass.
  • 07:05: ... galaxies, you automatically get the correct relationship  between rotation speed and ...
  • 02:32: ... the gravitational field in the outskirts to explain the high rotation speeds. ...
  • 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 depends on ...

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 ...
  • 02:59: ... this property that it returns to its starting state with a 720 degree rotation, not ...
  • 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: ... rotational degree of freedom in which a full wave cycle is a 720 degree rotation. In that case a 360 degree rotation puts a spinor perfectly out of phase ...
  • 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 ...
  • 06:49: ... a spinor perfectly out of phase compared to its starting point. So a 360 rotation introduces a negative sign to the spinor ...
  • 07:22: ... degree rotation to be returned to their initial state. But a 360 degree rotation shifts their phase by a half cycle and adds a -1 to the wavefunction. But we ...
  • 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 ...
  • 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 ...
  • 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. ...
  • 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 ...
  • 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. In that ...
  • 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 electrons, ...
  • 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 to ...
  • 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 function of how ...
  • 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 ...

2021-09-15: Neutron Stars: The Most Extreme Objects in the Universe

  • 10:06: ... right now, targeting   pulsars in our galaxy using their known rotation frequencies. They haven’t found anything yet,   but they might soon, giving ...

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.
  • 04:05: But the Sun is entirely fluid, and its rate of rotation speeds up towards the equator.

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 ...
  • 12:13: ... but instead by vectors, and behave  more intuitively - a 360 degree rotation brings them back to their original ...
  • 01:26: ... In fact the spin of an electron is far more fundamental than simple rotation - it’s a quantum property of particles, like mass or the various charges. ...
  • 07:02: ... two-valuedness manifesting as something like the direction  of a rotation axis, or the north-south pole of the magnetic ...
  • 12:13: ... but instead by vectors, and behave  more intuitively - a 360 degree rotation brings them back to their original ...
  • 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 it back to ...
  • 09:59: ... has  a phase that changes with orientation angle - and a 360 rotation pulls it out of  phase compared to its starting ...
  • 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.
  • 11:09: ... rotation,   but rather from the fact that they  have a rotational degree of freedom which leads to a conserved  quantity associated ...
  • 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 ...
  • 11:09: ... rotation,   but rather from the fact that they  have a rotational degree of freedom which leads to a conserved  quantity associated with ...
  • 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 of what ...
  • 12:44: ... difference in the rotational  properties of fermions and bosons   results in profound ...
  • 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 ...

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.
  • 03:43: For a rotating charge, that depends on the objects rate of rotation, or angular momentum, it's charge and it's mass.
  • 03:37: The strength of that rotational pool or the talk, is defined by the objects dipole moment.

2021-02-17: Gravitational Wave Background Discovered?

  • 00:00: ... rotating 1.4 times per second and this is the crab pulsar with its 30 rotations per second and this is a true millisecond pulsar at 174 rotations per ...

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.
  • 03:40: At a certain very high rotation rate, the inner and outer horizons merge - which means they both vanish.

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

  • 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 ...
  • 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 ...

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.
  • 13:26: That resists the inward flow just like rotation does in a Kerr black hole.
  • 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.

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 ...
  • 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 ...
  • 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 ...
  • 03:54: ... But if nothing can escape the event horizon, how can that internal rotation influence the ...
  • 09:37: ... energy is extracted from the rotational energy in the ergosphere, slowing the black hole’s spin. To get a little ...
  • 10:11: ... through the ergosphere in the direction of rotation will also extract rotational energy and emerge amplified in a process called ...
  • 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 ...
  • 09:37: ... energy is extracted from the rotational energy in the ergosphere, slowing the black hole’s spin. To get a little more ...
  • 10:11: ... through the ergosphere in the direction of rotation will also extract rotational energy and emerge amplified in a process called ...
  • 10:27: ... way the rotational energy can be extracted with, in principle, 100% efficiency. Oh, and you can ...
  • 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 ...

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 ...
  • 07:52: And the amount of rotation encodes information about the changes in geometry along the path.
  • 15:35: ... hole which comes from the fact that the outward centrifugal force of rotation partially counters the gravitatinally attraction - if you'll forgive my crude ...
  • 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 I'll ...

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.
  • 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.
  • 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 surface, but it ...
  • 06:47: Those loops form magnetic tubes around Earth’s rotational axis.

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: ... 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: ... so combine that with the axis direction from the jet and we have the rotation direction of the black hole – roughly clockwise from our perspective, ...
  • 09:19: ... 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: ... so combine that with the axis direction from the jet and we have the rotation direction of the black hole – roughly clockwise from our perspective, with an axis ...
  • 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 ...
  • 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 the jet and ...

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.
  • 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.
  • 04:07: ... example, if the factors driving the laws of motion are symmetric under rotation-- for example, the spherically-symmetric gravitational field experienced ...
  • 02:23: Snowflakes are symmetric under 60-degree rotation-- playing cards under a 180-degree rotation.
  • 02:53: A perfect sphere is continuously symmetric under rotational translations.

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.
  • 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.
  • 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.

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.
  • 00:27: But Earth's rotation slows, so that's a bad definition.

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.
  • 04:28: The rotation axis wobbles.

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?
  • 02:38: ... you adjust the radius and rotation rate of the room, you can make that force from the wall on your feet ...
  • 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.
  • 06:38: And apparently, a halo at that size and rotation could actually stay mechanically intact.
  • 02:38: ... you adjust the radius and rotation rate of the room, you can make that force from the wall on your feet just as ...
  • 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.
  • 04:57: ... concept of artificial gravity correct, given its small radius and high rotation rate, it ends up sweeping major Coriolis effect under the rug, especially the ...
  • 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.
  • 05:31: ... achieve 1 g, Ringworld's rotational velocity would be small enough that, just like on Earth, Coriolis ...
  • 08:10: ... is I can't actually find anything that the game gets wrong per se in its rotational artificial ...
  • 02:33: It's just the radius of the rotating structure multiplied by the square of its rotational speed in radians per second.
  • 05:31: ... achieve 1 g, Ringworld's rotational velocity would be small enough that, just like on Earth, Coriolis effects would ...
  • 02:49: ... examples-- "2001," "Ringworld," "Halo," and "Babylon 5"-- all which use rotation-induced artificial ...
  • 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 ...
  • 02:49: ... examples-- "2001," "Ringworld," "Halo," and "Babylon 5"-- all which use rotation-induced artificial ...
  • 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 ...
  • 02:49: ... examples-- "2001," "Ringworld," "Halo," and "Babylon 5"-- all which use rotation-induced artificial ...
  • 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 by ...

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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