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	2022-12-14: How Can Matter Be BOTH Liquid AND Gas? 17:05: Amorphant points out that we didn’t mention magnetic monopoles as an example of quasiparticles. 17:18: Actual magnetic monopoles, if they really exist, would be elementary particles, and we’ve done an episode on these before. 17:24: ... be created as quasiparticles by separating the poles of a regular dipole magnetic field, for example by careful manipulation of spins in a crystal ... 17:05: Amorphant points out that we didn’t mention magnetic monopoles as an example of quasiparticles. 17:18: Actual magnetic monopoles, if they really exist, would be elementary particles, and we’ve done an episode on these before.
	2022-11-23: How To See Black Holes By Catching Neutrinos 01:03: They report seeing neutrinos produced in the colossal magnetic fields surrounding a black hole with the mass of 10 million Suns. 09:26: ... know that AGNs have powerful magnetic fields because in many of them we see jets of high energy particles ... 01:03: They report seeing neutrinos produced in the colossal magnetic fields surrounding a black hole with the mass of 10 million Suns. 09:26: ... know that AGNs have powerful magnetic fields because in many of them we see jets of high energy particles blasted out ... 01:03: They report seeing neutrinos produced in the colossal magnetic fields surrounding a black hole with the mass of 10 million Suns. 10:10: Now a blazar is an AGN where a magnetically-channeled jet happens to be pointing more or less directly at us. 09:47: And collisions of magnetic-field-accelerated particles is exactly how we make neutrinos in our experiments.
	2022-09-28: Why Is 1/137 One of the Greatest Unsolved Problems In Physics? 02:36: ... spins are separated slightly by their interaction with their own orbital magnetic ...
	2022-09-14: Could the Higgs Boson Lead Us to Dark Matter? 04:06: ... gamma ray photons, which could be picked up by telescopes like the Alpha Magnetic ...
	2022-08-24: What Makes The Strong Force Strong? 11:32: That means photons can interact with objects without affecting their electric charge, and thus neutral objects can interact with magnetic fields.
	2022-06-30: Could We Decode Alien Physics? 07:38: ... define this rule. Say you have an electron moving   through a magnetic field. That field is going to apply a force in some direction to ... 16:39: ... light  sails that decelerate in the light and wind   and magnetic field of the destination star,  or Bussard ramjets - vast scoops ... 07:38: ... define this rule. Say you have an electron moving   through a magnetic field. That field is going to apply a force in some direction to that ... 16:39: ... light  sails that decelerate in the light and wind   and magnetic field of the destination star,  or Bussard ramjets - vast scoops that ... 07:38: ... the cross product. Force equals   charge times velocity cross magnetic field.  This is a type of vector multiplication where   the direction ... 16:39: ... your magnetic shield,   or for generating a hot plasma in that magnetic field to vaporize particles. There are lots of   novel shielding ... 07:38: ... using the left-hand rule by placing a minus sign in front of your magnetic force equation.   Well that minus sign can equally be ... 16:39: ... an electromagnetic shield would be sufficient. Well actually a magnetic shield may be   enough to block many charged particles, but  ...
	2022-06-22: Is Interstellar Travel Impossible? 10:38: There are more advanced options for the latter - for example, deflection of grains by magnetic fields or a shielding mass moving in front of the ship. 12:29: These things are accelerated in the monstrous magnetic fields of black holes and supernovae and of the galaxy itself. 10:38: There are more advanced options for the latter - for example, deflection of grains by magnetic fields or a shielding mass moving in front of the ship. 12:29: These things are accelerated in the monstrous magnetic fields of black holes and supernovae and of the galaxy itself.
	2022-06-01: What If Physics IS NOT Describing Reality? 04:56: ... ask this question with a Stern   Gerlach apparatus, where the magnetic moment  of the particles interact with a magnetic field   ...
	2022-05-04: Space DOES NOT Expand Everywhere 13:50: ... is created in a particle collider it travels through the powerful magnetic fields of the detector. The amount by which its path is deflected by ...
	2022-04-27: How the Higgs Mechanism Give Things Mass 05:38: ... this random thermal motion gets overpowered by the   magnetic interaction and they end up all aligning.  The equations of ...
	2022-03-08: Is the Proxima System Our Best Hope For Another Earth? 11:22: ... convection through the star’s body generates crazy magnetic storms, which can cause the star to have powerful outbursts - flares - ... 11:43: ... sufficiently thick atmosphere and strong planetary magnetic field could in principle protect any surface dwellers, who would then ... 11:22: ... convection through the star’s body generates crazy magnetic storms, which can cause the star to have powerful outbursts - flares - that ...
	2022-02-23: Are Cosmic Strings Cracks in the Universe? 04:51: ... pulling them towards the same value, just   like how the magnetic dipoles in a ferromagnet  drag each other into alignment. So, when ... 07:33: ... a zero-dimensional, point-like  topological defect would be a magnetic monopoles,   which we talked about recently. There are ... 04:51: ... pulling them towards the same value, just   like how the magnetic dipoles in a ferromagnet  drag each other into alignment. So, when ... 07:33: ... a zero-dimensional, point-like  topological defect would be a magnetic monopoles,   which we talked about recently. There are also  ways to produce 2-D ...
	2022-01-19: How To Build The Universe in a Computer 09:34: ... don’t get me started about the complexity  of including magnetic fields, or of Einstein’s general relativity when the gravitational field ...
	2021-10-13: New Results in Quantum Tunneling vs. The Speed of Light 10:48: ... phenomenon is called Larmor precession, in which a particle’s dipole magnetic field, which is defined by its spin axis, precesses like a top in an ... 11:20: ... those ones, their spins were altered by the magnetic field of the laser, and the longer they spent inside the barrier, the ... 14:15: In the last episode we talked about why physicists believe magnetic monopoles. 14:19: ... - the radiating knots in the Higgs field that might lead to magnetic ... 15:23: Erik says that if magnetic monopoles are massive enough to collapse the early univeres, wouldn’t we only find them inside black holes? 15:36: ... certainly possible that magnetic monopoles to end up inside black holes, in fact some recent work ... 15:48: ... would still behave like a monopole in that the black hole would radiate magnetic field ... 16:08: As it is, the magnetic fields we observe around black holes seem more consistent with regular dipole fields, with both north and south poles. 16:23: ... Magnetic monopoles aside, why did Moody arrange for the whole Goblet of Fire ... 10:48: ... phenomenon is called Larmor precession, in which a particle’s dipole magnetic field, which is defined by its spin axis, precesses like a top in an external ... 11:20: ... those ones, their spins were altered by the magnetic field of the laser, and the longer they spent inside the barrier, the more ... 15:48: ... would still behave like a monopole in that the black hole would radiate magnetic field ... 16:08: As it is, the magnetic fields we observe around black holes seem more consistent with regular dipole fields, with both north and south poles. 15:36: ... inside black holes, in fact some recent work suggests that an individual magnetic monopole would manifest as a black hole - in that it would have an event ... 14:15: In the last episode we talked about why physicists believe magnetic monopoles. 14:19: ... - the radiating knots in the Higgs field that might lead to magnetic monopoles. ... 15:23: Erik says that if magnetic monopoles are massive enough to collapse the early univeres, wouldn’t we only find them inside black holes? 15:36: ... certainly possible that magnetic monopoles to end up inside black holes, in fact some recent work suggests that an ... 16:23: ... Magnetic monopoles aside, why did Moody arrange for the whole Goblet of Fire thing when he ...
	2021-10-05: Why Magnetic Monopoles SHOULD Exist 00:08: It’s the magnetic monopole - and of all the fantastical beasts of particle physics, this is perhaps the most likely to actually exist. 00:50: You get a dipole magnetic field that’s very similar to the dipole electric field. 00:55: So if we cut this bar in half surely we get a pair of magnetic charges similar to our electric charges, right? 01:11: ... doesn’t matter how many times you slice it - you’ll never get isolated magnetic charges - what we call magnetic ... 01:51: ... other popular way to make a dipole magnetic field is the electromagnet - where were push electrons around in a ... 02:06: And according to classical electrodynamics, moving electric charge is the source of the magnetic field. 02:12: If that’s true then, why should we even expect there to be isolated magnetic charges - magnetic monopoles? 02:22: The non-existence of magnetic monopoles is codified in the mathematics of electrodynamics. 02:32: It states that the divergence of a magnetic field is zero. 02:51: Magnetic field lines can form loops or head out toward infinity, but they never end. 02:57: According to this law there are no magnetic monopoles. 03:23: This is them without any charges - electric or magnetic. 03:26: E is the electric field and B is the magnetic field. 03:40: You could also have symmetry between these equations if there was such a thing as magnetic charge. 03:46: If you add magnetic charges to these equations then you get a magnetic force that looks exactly like the electrostatic force. 04:05: ... nothing in Maxwell’s equations that really says magnetic monopoles can’t exist except for the fact that James Clark Maxwell set ... 04:18: But in principle it could exist, and so could magnetic monopoles. 04:54: ... require this - but in that version of electromagnetism, the electric and magnetic fields are VERY different from each other, and not at all ... 05:09: ... particular, the magnetic field emerging from the quantum theory must have zero divergence - its ... 05:22: So perhaps here we have our reason for the apparent non-existence of magnetic monopoles. 05:49: But then in 1931, just before his antimatter thing was verified, Dirac made another prediction - of the existence of magnetic monopoles. 06:00: ... you start with a dipole magnetic field, you can approximate a monopole by moving the ends far enough ... 06:23: So make the width of the coil much smaller than the length, and it looks like two isolated magnetic charges. 06:30: ... the string part of the Dirac string is fundamentally undetectable, then magnetic monopoles can ... 06:49: So magnetic fields affect charged particles. 07:09: ... presence of the string, with its magnetic fields, should introduce different phase shifts depending on which side ... 08:13: ... charge - electric charge has to be discrete if there’s even a single magnetic monopole in the entire ... 08:34: ... this as a prediction of charge quantization, you can also flip it: magnetic monopoles are possible if electric charge is ... 09:19: Well it turns out that magnetic monopoles are inevitable in all “GUTs”. 10:55: And it turns out these knots in the Higgs field in GUT theories behave as massive particles with magnetic charge - magnetic monopoles. 11:12: ... turns out that GUT theories generically predict these magnetic monopoles, and that they should be A) very massive, and B) should form ... 11:29: The fact that magnetic monopoles should exist in these theories was both exciting and problematic. 12:16: ... should have happened after the production of magnetic monopoles, and so should have thrown these things far apart that there ... 12:36: ... you have one of these magnetic monopoles in your lab it wouldn’t be too hard to spot - for example a ... 13:24: ... also look for magnetic monopoles coming from space - typically using cosmic ray observatories - ... 13:37: We have been hunting for magnetic monopoles for longer than just about any particle. 14:18: Kyle, we are taught by Paul Dirac that if there's even a single magnetic monopole in the entire universe then electric charge must be quantized. 14:28: We don't know where that single magnetic monopole would be, but it's rare and special and so we decided to name it after you. 14:36: ... now Kyle, the magnetic monopole Kyle - is doubly important - sure, it ensures the quantization ... 03:40: You could also have symmetry between these equations if there was such a thing as magnetic charge. 04:05: ... can’t exist except for the fact that James Clark Maxwell set the magnetic charge to zero because he didn’t believe it ... 10:55: And it turns out these knots in the Higgs field in GUT theories behave as massive particles with magnetic charge - magnetic monopoles. 00:55: So if we cut this bar in half surely we get a pair of magnetic charges similar to our electric charges, right? 01:11: ... doesn’t matter how many times you slice it - you’ll never get isolated magnetic charges - what we call magnetic ... 02:12: If that’s true then, why should we even expect there to be isolated magnetic charges - magnetic monopoles? 03:46: If you add magnetic charges to these equations then you get a magnetic force that looks exactly like the electrostatic force. 06:23: So make the width of the coil much smaller than the length, and it looks like two isolated magnetic charges. 01:11: ... doesn’t matter how many times you slice it - you’ll never get isolated magnetic charges - what we call magnetic ... 02:12: If that’s true then, why should we even expect there to be isolated magnetic charges - magnetic monopoles? 00:50: You get a dipole magnetic field that’s very similar to the dipole electric field. 01:51: ... other popular way to make a dipole magnetic field is the electromagnet - where were push electrons around in a circle In ... 02:06: And according to classical electrodynamics, moving electric charge is the source of the magnetic field. 02:32: It states that the divergence of a magnetic field is zero. 02:51: Magnetic field lines can form loops or head out toward infinity, but they never end. 03:26: E is the electric field and B is the magnetic field. 05:09: ... particular, the magnetic field emerging from the quantum theory must have zero divergence - its field ... 06:00: ... you start with a dipole magnetic field, you can approximate a monopole by moving the ends far enough apart and ... 13:24: ... using cosmic ray observatories - or contributing to the Earth’s magnetic field - and in a number of other ... 05:09: ... particular, the magnetic field emerging from the quantum theory must have zero divergence - its field lines can ... 02:51: Magnetic field lines can form loops or head out toward infinity, but they never end. 04:54: ... require this - but in that version of electromagnetism, the electric and magnetic fields are VERY different from each other, and not at all interchangeable as ... 06:49: So magnetic fields affect charged particles. 07:09: ... presence of the string, with its magnetic fields, should introduce different phase shifts depending on which side of the ... 06:49: So magnetic fields affect charged particles. 03:46: If you add magnetic charges to these equations then you get a magnetic force that looks exactly like the electrostatic force. 00:08: It’s the magnetic monopole - and of all the fantastical beasts of particle physics, this is perhaps the most likely to actually exist. 08:13: ... charge - electric charge has to be discrete if there’s even a single magnetic monopole in the entire ... 14:18: Kyle, we are taught by Paul Dirac that if there's even a single magnetic monopole in the entire universe then electric charge must be quantized. 14:28: We don't know where that single magnetic monopole would be, but it's rare and special and so we decided to name it after you. 14:36: ... now Kyle, the magnetic monopole Kyle - is doubly important - sure, it ensures the quantization of all ... 00:08: It’s the magnetic monopole - and of all the fantastical beasts of particle physics, this is perhaps the most likely to actually exist. 14:36: ... now Kyle, the magnetic monopole Kyle - is doubly important - sure, it ensures the quantization of all charge, ... 01:11: ... you slice it - you’ll never get isolated magnetic charges - what we call magnetic monopoles. ... 02:12: If that’s true then, why should we even expect there to be isolated magnetic charges - magnetic monopoles? 02:22: The non-existence of magnetic monopoles is codified in the mathematics of electrodynamics. 02:57: According to this law there are no magnetic monopoles. 04:05: ... nothing in Maxwell’s equations that really says magnetic monopoles can’t exist except for the fact that James Clark Maxwell set the ... 04:18: But in principle it could exist, and so could magnetic monopoles. 05:22: So perhaps here we have our reason for the apparent non-existence of magnetic monopoles. 05:49: But then in 1931, just before his antimatter thing was verified, Dirac made another prediction - of the existence of magnetic monopoles. 06:30: ... the string part of the Dirac string is fundamentally undetectable, then magnetic monopoles can ... 08:34: ... this as a prediction of charge quantization, you can also flip it: magnetic monopoles are possible if electric charge is ... 09:19: Well it turns out that magnetic monopoles are inevitable in all “GUTs”. 10:55: And it turns out these knots in the Higgs field in GUT theories behave as massive particles with magnetic charge - magnetic monopoles. 11:12: ... turns out that GUT theories generically predict these magnetic monopoles, and that they should be A) very massive, and B) should form ... 11:29: The fact that magnetic monopoles should exist in these theories was both exciting and problematic. 12:16: ... should have happened after the production of magnetic monopoles, and so should have thrown these things far apart that there may be very ... 12:36: ... you have one of these magnetic monopoles in your lab it wouldn’t be too hard to spot - for example a monopole ... 13:24: ... also look for magnetic monopoles coming from space - typically using cosmic ray observatories - or ... 13:37: We have been hunting for magnetic monopoles for longer than just about any particle. 13:24: ... also look for magnetic monopoles coming from space - typically using cosmic ray observatories - or contributing ...
	2021-09-15: Neutron Stars: The Most Extreme Objects in the Universe 01:42: ... we encounter is its magnetosphere. This is the strongest magnetic field in the universe. Even   the weakest neutron star fields ... 02:00: ... pairs are created out of the extreme  energy photons in the magnetic field.   That field then becomes a particle ... 11:29: ... an essential part of maintaining the neutron star’s enormous magnetic ... 01:42: ... we encounter is its magnetosphere. This is the strongest magnetic field in the universe. Even   the weakest neutron star fields are a ... 11:29: ... an essential part of maintaining the neutron star’s enormous magnetic field. ... 02:00: ... pairs are created out of the extreme  energy photons in the magnetic field.   That field then becomes a particle accelerator, with electron ...
	2021-09-07: First Detection of Light from Behind a Black Hole 01:21: And the more recent version of this in polarized light shows the grain of the magnetic field right near the black hole’s edge. 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. 01:21: And the more recent version of this in polarized light shows the grain of the magnetic field right near the black hole’s edge. 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.
	2021-08-18: How Vacuum Decay Would Destroy The Universe 02:52: ... example, for an electromagnetic wave  - a photon - the electric and magnetic   fields rise and fall between positive and  negative values, but the ...
	2021-08-10: How to Communicate Across the Quantum Multiverse 16:27: ... Persona asks what happens to the star’s magnetic fields after it goes supernova. And then guesses the correct answer - it ... 16:58: ... by watching the radio light emitted by electrons spiraling in that magnetic field - what we call synchrotron radiation. Galactic magnetic fields ... 16:27: ... reach the earth. The magnetic fields then go on to add to the galaxy’s magnetic field. ... 16:58: ... by watching the radio light emitted by electrons spiraling in that magnetic field - what we call synchrotron radiation. Galactic magnetic fields have very ... 16:27: ... Persona asks what happens to the star’s magnetic fields after it goes supernova. And then guesses the correct answer - it ... 16:58: ... in that magnetic field - what we call synchrotron radiation. Galactic magnetic fields have very clear bubble-like structures that come from past ...
	2021-08-03: How An Extreme New Star Could Change All Cosmology 03:19: ... all over the place in a way that suggests the presence of gigantic magnetic fields. Fields around a billion times stronger than the earth or sun’s ... 08:48: ... part is that it’s rotating extremely quickly and has a crazy strong magnetic field. We just don’t see these extreme properties in the white dwarfs ... 09:51: ... the orbits of the parent stars. This process also explains the intense magnetic fields. Magnetic fields in stars and planets are generated by dynamos - ... 14:52: ... your praises, Charlie, and extend their white dwarf blessings: may your magnetic fields stay untangled, your electrons be ever degenerate, and may your ... 15:05: ... last time we took a magnetic tour of the universe, exploring how magnetism shapes our cosmos from the ... 15:55: ... asks whether magnetic fields have any measurable effect on the orbits of stars around the ... 16:19: So the locations that stars formed may be influenced by magnetic fields, which in turn affects their orbits. So the answer is yes, sort of. 16:29: ... Charlton and Brandon Munshaw ask whether magnetic field lines are really “lines” versus some sort of continuous thing. ... 17:08: ... number of you ask questions about the potential role of magnetic fields in the universe that all have the answer I just gave - can ... 15:05: ... shapes our cosmos from the scale of planets up to entire galaxies. That magnetic episode .. attracted many ... 03:19: ... fields. Fields around a billion times stronger than the earth or sun’s magnetic field. That’s at the top tier of the most magnetic white ... 08:48: ... part is that it’s rotating extremely quickly and has a crazy strong magnetic field. We just don’t see these extreme properties in the white dwarfs produced ... 09:51: ... motion to jump start a dynamo powerful enough to produce the observed magnetic field. ... 15:55: ... on the orbits of stars around the galaxy. Not directly. The galactic magnetic field is very weak compared to the magnetic fields of stars, or even planets. ... 16:29: ... Charlton and Brandon Munshaw ask whether magnetic field lines are really “lines” versus some sort of continuous thing. Well it's ... 15:55: ... respond to that field directly. However gas does respond to the galactic magnetic field - it can definitely move gas around and even trigger gas to collapse into ... 16:29: ... Charlton and Brandon Munshaw ask whether magnetic field lines are really “lines” versus some sort of continuous thing. Well it's ... 03:19: ... all over the place in a way that suggests the presence of gigantic magnetic fields. Fields around a billion times stronger than the earth or sun’s magnetic ... 09:51: ... the orbits of the parent stars. This process also explains the intense magnetic fields. Magnetic fields in stars and planets are generated by dynamos - ... 14:52: ... your praises, Charlie, and extend their white dwarf blessings: may your magnetic fields stay untangled, your electrons be ever degenerate, and may your mass ... 15:55: ... asks whether magnetic fields have any measurable effect on the orbits of stars around the galaxy. Not ... 16:19: So the locations that stars formed may be influenced by magnetic fields, which in turn affects their orbits. So the answer is yes, sort of. 17:08: ... number of you ask questions about the potential role of magnetic fields in the universe that all have the answer I just gave - can magnetic ... 03:19: ... all over the place in a way that suggests the presence of gigantic magnetic fields. Fields around a billion times stronger than the earth or sun’s magnetic field. ... 09:51: ... the orbits of the parent stars. This process also explains the intense magnetic fields. Magnetic fields in stars and planets are generated by dynamos - self-sustaining ... 14:52: ... your praises, Charlie, and extend their white dwarf blessings: may your magnetic fields stay untangled, your electrons be ever degenerate, and may your mass remain ... 15:05: ... last time we took a magnetic tour of the universe, exploring how magnetism shapes our cosmos from the ... 03:19: ... the earth or sun’s magnetic field. That’s at the top tier of the most magnetic white ...
	2021-07-21: How Magnetism Shapes The Universe 00:02: As far as the north magnetic pole, where the needle starts spinning wildly? 00:07: Compass needles align with magnetic field lines, and on the precise spot of magnetic north, those field lines are vertical. 01:12: Personally, I’d rather be able to see magnetic fields. 01:43: Even if the substance is electrically neutral you’ll still get a magnetic field as long as the charges are moving in opposite directions. 01:51: That means magnetic fields can add up - and magnetism adds up to having enormous influence on the development of structure in our universe. 02:01: Understanding magnetic fields is of fundamental importance to astrophysicists. 02:12: Magnetic field lines form in concentric circles around moving charges. 02:26: So those are magnetic field lines - but what do they do? 02:30: ... the net result of that is that charged particles tend to spiral around magnetic field ... 02:43: ... spins in a ferromagnet, then that current will want to loop around the magnetic ... 03:17: As with the gravitational field, in a sense there’s only one universal magnetic field. 03:23: ... field loops back - but some of those field lines connect to this greater magnetic field of the solar system - and even of the ... 03:38: Now I don’t want to spend too much time in the solar system - greater magnetic wonders lie beyond. 04:16: Magnetic field lines cross each other, and enormous magnetic energy densities pile up. 04:29: ... these field lines snap and then reconnect, and in the process spray that magnetic field out into the solar system - carrying high energy particles with ... 04:43: Follow one of these magnetic blasts and you’ll spiral through the solar system on a giangantic magnetic tornado. 04:49: This is still the Sun’s magnetic field, which connects here and there to the piddling little fields of the planets. 04:55: About 4x the distance to Pluto, the Sun’s magnetic field connects to the field of the galaxy itself. 05:46: Beyond the heliosphere, seeing magnetic fields gets trickier. 06:08: These specks tend to align with the local magnetic field of the Galaxy in exactly the same way as our iron filings align around a bar magnet. 06:29: The light gets polarized - which means the direction of its electric and magnetic fields pick up a preferred direction rather than being random. 06:37: By measuring this polarization we can map the direction of these tiny compass needles, and so map the magnetic field of the Milky Way. 07:01: KInda makes me wonder if van Gogh could see magnetic fields. 07:05: Actually there’s a more traditional way to map the magnetic fields of galaxies. 07:35: If the electric and magnetic fields of a collection of photons all tend to point in the same direction, we say the light is linearly polarized. 07:55: The electrons in their magnetic fields tend to slow one circular polarization direction more than the other. 08:12: So by measuring the Faraday rotation of distant radio sources we can also map magnetic fields. 08:21: We even have clear views of magnetic fields in many distant spiral galaxies. 08:30: These are the densest regions of those galactic disks - places where magnetic fields have confined the charged particles of the interstellar plasma. 08:39: And that plasma in turn drags the magnetic fields in orbit around the galaxy. 08:44: OK, so galaxies have magnetic fields. 08:47: But where do those magnetic fields come from? 08:51: Large-scale magnetic fields can grow and reinforce themselves in very particular configurations called dynamos. 09:38: Those supernovae may also give us the seeds of magnetic fields that can then be amplified by the galactic dynamo. 09:45: However it got there, the Milky Way has built itself a substantial magnetic field. 09:53: Magnetic fields generated by collapsing gas clouds help to slow the rotation of those clouds - expel angular momentum. 10:05: And magnetic fields also facilitate star formation after stars die. 10:09: ... Magnetic blasts accompany every supernova explosion, and these help to compress ... 10:27: But the galactic magnetic field constrains that flow, funneling some of it into vast galactic fountains erupting from the poles. 10:34: That’s right - if you follow a magnetic field line too far, you may accidentally leave the galaxy. 10:53: The other cool thing that galactic magnetic fields do is that they act as colossal particle accelerators. 11:08: Electrons and atomic nuclei can be accelerated in this magnetic field to high energies - into what we call cosmic rays. 11:15: These can also be accelerated in the magnetic shock-fronts of supernova explosions. 11:20: But the most energetic cosmic rays are accelerated by the strongest magnetic fields. 11:40: Intense magnetic fields live just above the event horizon of some of thses black hole, and thread the infalling disk. 11:54: ... even taken our first picture of the such a magnetic field - in the polarized light surrounding the M81 supermassive black ... 12:05: But there’s an even more spectacular result of these magnetic fields. 12:23: ... jets carry magnetic fields out into the cosmos, and we see them through the radio light ... 12:32: OK, we’ve ridden our magnetic field lines pretty far and into some strange places. 12:38: To summarize what we’ve learned: magnetic fields are ubiquitous, powerful, and extremely complicated. 12:53: But it turns out that without cosmic-scale magnetic fields we probably wouldn’t be here today. 12:59: ... are spending more and more time learning how to map and to model magnetic fields, to better understand the mysteries of this magnetic space ... 04:43: Follow one of these magnetic blasts and you’ll spiral through the solar system on a giangantic magnetic tornado. 10:09: ... Magnetic blasts accompany every supernova explosion, and these help to compress gas in ... 04:16: Magnetic field lines cross each other, and enormous magnetic energy densities pile up. 00:07: Compass needles align with magnetic field lines, and on the precise spot of magnetic north, those field lines are vertical. 01:43: Even if the substance is electrically neutral you’ll still get a magnetic field as long as the charges are moving in opposite directions. 02:12: Magnetic field lines form in concentric circles around moving charges. 02:26: So those are magnetic field lines - but what do they do? 02:30: ... the net result of that is that charged particles tend to spiral around magnetic field ... 02:43: ... spins in a ferromagnet, then that current will want to loop around the magnetic field. ... 03:17: As with the gravitational field, in a sense there’s only one universal magnetic field. 03:23: ... field loops back - but some of those field lines connect to this greater magnetic field of the solar system - and even of the ... 04:16: Magnetic field lines cross each other, and enormous magnetic energy densities pile up. 04:29: ... these field lines snap and then reconnect, and in the process spray that magnetic field out into the solar system - carrying high energy particles with ... 04:49: This is still the Sun’s magnetic field, which connects here and there to the piddling little fields of the planets. 04:55: About 4x the distance to Pluto, the Sun’s magnetic field connects to the field of the galaxy itself. 06:08: These specks tend to align with the local magnetic field of the Galaxy in exactly the same way as our iron filings align around a bar magnet. 06:37: By measuring this polarization we can map the direction of these tiny compass needles, and so map the magnetic field of the Milky Way. 09:45: However it got there, the Milky Way has built itself a substantial magnetic field. 10:27: But the galactic magnetic field constrains that flow, funneling some of it into vast galactic fountains erupting from the poles. 10:34: That’s right - if you follow a magnetic field line too far, you may accidentally leave the galaxy. 11:08: Electrons and atomic nuclei can be accelerated in this magnetic field to high energies - into what we call cosmic rays. 11:54: ... even taken our first picture of the such a magnetic field - in the polarized light surrounding the M81 supermassive black hole ... 12:32: OK, we’ve ridden our magnetic field lines pretty far and into some strange places. 11:54: ... even taken our first picture of the such a magnetic field - in the polarized light surrounding the M81 supermassive black hole ... 04:55: About 4x the distance to Pluto, the Sun’s magnetic field connects to the field of the galaxy itself. 10:27: But the galactic magnetic field constrains that flow, funneling some of it into vast galactic fountains erupting from the poles. 00:07: Compass needles align with magnetic field lines, and on the precise spot of magnetic north, those field lines are vertical. 02:12: Magnetic field lines form in concentric circles around moving charges. 02:26: So those are magnetic field lines - but what do they do? 02:30: ... the net result of that is that charged particles tend to spiral around magnetic field lines. ... 04:16: Magnetic field lines cross each other, and enormous magnetic energy densities pile up. 12:32: OK, we’ve ridden our magnetic field lines pretty far and into some strange places. 01:12: Personally, I’d rather be able to see magnetic fields. 01:51: That means magnetic fields can add up - and magnetism adds up to having enormous influence on the development of structure in our universe. 02:01: Understanding magnetic fields is of fundamental importance to astrophysicists. 05:46: Beyond the heliosphere, seeing magnetic fields gets trickier. 06:29: The light gets polarized - which means the direction of its electric and magnetic fields pick up a preferred direction rather than being random. 07:01: KInda makes me wonder if van Gogh could see magnetic fields. 07:05: Actually there’s a more traditional way to map the magnetic fields of galaxies. 07:35: If the electric and magnetic fields of a collection of photons all tend to point in the same direction, we say the light is linearly polarized. 07:55: The electrons in their magnetic fields tend to slow one circular polarization direction more than the other. 08:12: So by measuring the Faraday rotation of distant radio sources we can also map magnetic fields. 08:21: We even have clear views of magnetic fields in many distant spiral galaxies. 08:30: These are the densest regions of those galactic disks - places where magnetic fields have confined the charged particles of the interstellar plasma. 08:39: And that plasma in turn drags the magnetic fields in orbit around the galaxy. 08:44: OK, so galaxies have magnetic fields. 08:47: But where do those magnetic fields come from? 08:51: Large-scale magnetic fields can grow and reinforce themselves in very particular configurations called dynamos. 09:38: Those supernovae may also give us the seeds of magnetic fields that can then be amplified by the galactic dynamo. 09:53: Magnetic fields generated by collapsing gas clouds help to slow the rotation of those clouds - expel angular momentum. 10:05: And magnetic fields also facilitate star formation after stars die. 10:53: The other cool thing that galactic magnetic fields do is that they act as colossal particle accelerators. 11:20: But the most energetic cosmic rays are accelerated by the strongest magnetic fields. 11:40: Intense magnetic fields live just above the event horizon of some of thses black hole, and thread the infalling disk. 12:05: But there’s an even more spectacular result of these magnetic fields. 12:23: ... jets carry magnetic fields out into the cosmos, and we see them through the radio light emitted by ... 12:38: To summarize what we’ve learned: magnetic fields are ubiquitous, powerful, and extremely complicated. 12:53: But it turns out that without cosmic-scale magnetic fields we probably wouldn’t be here today. 12:59: ... are spending more and more time learning how to map and to model magnetic fields, to better understand the mysteries of this magnetic space ... 09:53: Magnetic fields generated by collapsing gas clouds help to slow the rotation of those clouds - expel angular momentum. 11:40: Intense magnetic fields live just above the event horizon of some of thses black hole, and thread the infalling disk. 06:29: The light gets polarized - which means the direction of its electric and magnetic fields pick up a preferred direction rather than being random. 07:55: The electrons in their magnetic fields tend to slow one circular polarization direction more than the other. 00:07: Compass needles align with magnetic field lines, and on the precise spot of magnetic north, those field lines are vertical. 00:02: As far as the north magnetic pole, where the needle starts spinning wildly? 11:15: These can also be accelerated in the magnetic shock-fronts of supernova explosions. 12:59: ... and to model magnetic fields, to better understand the mysteries of this magnetic space ... 04:43: Follow one of these magnetic blasts and you’ll spiral through the solar system on a giangantic magnetic tornado. 03:38: Now I don’t want to spend too much time in the solar system - greater magnetic wonders lie beyond. 03:50: This is a violent place, magnetically speaking.
	2021-07-07: Electrons DO NOT Spin 00:47: ... - suspend a cylinder of iron from a thread and switch on a vertical magnetic field. The cylinder immediately starts rotating with a constant speed. ... 02:25: ... that these energy levels tend to split when atoms are put in an external magnetic field.  This Zeeman effect was explained by Lorentz himself with ... 03:20: ... But then came the anomalous  Zeeman effect. In some cases, the magnetic field causes energy levels to split even further  - for reasons ... 03:48: ... that has huge problems. For example, in order to produce the observed magnetic moment they’d need to be spinning  faster than the speed of light. ... 04:40: ... like  in the Einstein de-Haas effect, and it also gives electrons a magnetic field. An electron’s  spin is an entirely quantum mechanical ... 05:15: ... by Walther Gerlach a year later. In it silver atoms are fired through a magnetic field with a gradient - in this example stronger towards the north  ... 05:31: A lone electron in the outer shell of the silver atoms grants the atom a magnetic moment. 05:37: ... means the external magnetic field induces a  force on the atoms that depends on the direction ... 07:02: ... the direction  of a rotation axis, or the north-south pole of the magnetic ... 11:34: ... derive the right values of the  electron spin angular momentum and magnetic moment by looking at the energy and charge  currents in the so ... 07:02: ... the direction  of a rotation axis, or the north-south pole of the magnetic dipole. ... 00:47: ... - suspend a cylinder of iron from a thread and switch on a vertical magnetic field. The cylinder immediately starts rotating with a constant speed. At first ... 02:25: ... around the atom, that motion  leads to a magnetic moment - a dipole magnetic field like a tiny bar magnet. The different alignments of that orbital ... 03:20: ... But then came the anomalous  Zeeman effect. In some cases, the magnetic field causes energy levels to split even further  - for reasons that ... 04:40: ... like  in the Einstein de-Haas effect, and it also gives electrons a magnetic field. An electron’s  spin is an entirely quantum mechanical property, and ... 05:15: ... by Walther Gerlach a year later. In it silver atoms are fired through a magnetic field with a gradient - in this example stronger towards the north  pole ... 05:37: ... means the external magnetic field induces a  force on the atoms that depends on the direction that ... 02:25: ... field like a tiny bar magnet. The different alignments of that orbital magnetic field relative to the external field turns one energy level into ... 00:47: ... with. Except there was - or at least there sort of was. The external magnetic field  magnetized the iron, causing the electrons in the iron’s outer shells to ... 02:25: ... that these energy levels tend to split when atoms are put in an external magnetic field.  This Zeeman effect was explained by Lorentz himself with the ideas of ... 00:47: ... with. Except there was - or at least there sort of was. The external magnetic field  magnetized the iron, causing the electrons in the iron’s outer shells to align ... 02:25: ... charge moving in circles around the atom, that motion  leads to a magnetic moment - a dipole magnetic field like a tiny bar magnet. The different ... 03:20: ... that sort of works is  to say that each electron has its own magnetic moment - by itself it acts like a tiny bar magnet. So you have the alignment of ... 03:48: ... that has huge problems. For example, in order to produce the observed magnetic moment they’d need to be spinning  faster than the speed of light. This ... 05:31: A lone electron in the outer shell of the silver atoms grants the atom a magnetic moment. 11:34: ... derive the right values of the  electron spin angular momentum and magnetic moment by looking at the energy and charge  currents in the so called ... 02:25: ... charge moving in circles around the atom, that motion  leads to a magnetic moment - a dipole magnetic field like a tiny bar magnet. The different alignments ... 03:20: ... that sort of works is  to say that each electron has its own magnetic moment - by itself it acts like a tiny bar magnet. So you have the alignment of ... 05:37: ... force on the atoms that depends on the direction that these little magnetic moments are pointing  relative to that field. Those that are perfectly ... 04:40: ... weirdness, let me give you one more  experiment that reveals the magnetic properties that result from ... 05:37: ... be deflected by less. So a stream of silver atoms with randomly aligned magnetic  moments is sent through the magnetic ... 07:02: ... not only do electrons have this magnetic  moment without rotation, but the direction of the underlying ... 05:37: ... be deflected by less. So a stream of silver atoms with randomly aligned magnetic  moments is sent through the magnetic ... 07:02: ... moment without rotation, but the direction of the underlying magnetic  momentum is fundamentally quantum.   The direction of this "spin" ...
	2021-06-09: Are We Running Out of Space Above Earth? 12:59: ... to fall faster, or even electromagnetic tethers which push on earth’s magnetic field to deorbit a ...
	2021-04-21: The NEW Warp Drive Possibilities 14:41: ... makes it pretty hard to watch tau particles precess in magnetic fields, and so far the g-factor for the tau hasn’t even been measured to ... 17:54: ... If the Quantum Zeno Effect plays a role in birds' ability to see magnetic fields, then according to the Many-Worlds interpretation are there many, ... 14:41: ... makes it pretty hard to watch tau particles precess in magnetic fields, and so far the g-factor for the tau hasn’t even been measured to 1 ... 17:54: ... If the Quantum Zeno Effect plays a role in birds' ability to see magnetic fields, then according to the Many-Worlds interpretation are there many, many ...
	2021-04-07: Why the Muon g-2 Results Are So Exciting! 01:18: And that's the anomalous magnetic dipole moment of the muon. 01:35: What's an anomalous magnetic dipole moment? 01:41: We've actually talked at about the anomalous magnetic dipole moment before in terms of the electron. 02:05: One of the interactions that QED describes is how a charge particle will tend to rotate to align with a magnetic field. 03:15: ... particles with quantum spin do generate a magnetic field, same as if you send an electric charge around a looped wire, or ... 03:25: The result is a dipole magnetic field with a North and a South pole. 03:29: Place an object with such a field inside a second magnetic field, and the object will tend to rotate to align with that field. 04:15: So the electron responds to a magnetic field twice as strongly compared to what you'd expect for an equivalent classical rotating charge. 05:23: We can represent an electron interacting with a magnetic field, with the simplest possible Feynman diagram. 05:48: ... is for the electron to emit a virtual photon just prior to absorbing the magnetic field photon, and then reabsorbing that virtual ... 06:34: By the way, the anomalous in the anomalous magnetic dipole moment, refers to that little bit extra after the two. 09:41: At the Fermilab experiment, physicists send muons flying at nearly the speed of light around a 50 foot diameter magnetic tube. 09:49: The muons interact with the magnetic field and their own magnetic dipole axis, rotate like a top just before it falls. 01:18: And that's the anomalous magnetic dipole moment of the muon. 01:35: What's an anomalous magnetic dipole moment? 01:41: We've actually talked at about the anomalous magnetic dipole moment before in terms of the electron. 06:34: By the way, the anomalous in the anomalous magnetic dipole moment, refers to that little bit extra after the two. 09:49: The muons interact with the magnetic field and their own magnetic dipole axis, rotate like a top just before it falls. 01:18: And that's the anomalous magnetic dipole moment of the muon. 01:35: What's an anomalous magnetic dipole moment? 01:41: We've actually talked at about the anomalous magnetic dipole moment before in terms of the electron. 06:34: By the way, the anomalous in the anomalous magnetic dipole moment, refers to that little bit extra after the two. 02:05: One of the interactions that QED describes is how a charge particle will tend to rotate to align with a magnetic field. 03:15: ... particles with quantum spin do generate a magnetic field, same as if you send an electric charge around a looped wire, or have ... 03:25: The result is a dipole magnetic field with a North and a South pole. 03:29: Place an object with such a field inside a second magnetic field, and the object will tend to rotate to align with that field. 04:15: So the electron responds to a magnetic field twice as strongly compared to what you'd expect for an equivalent classical rotating charge. 05:23: We can represent an electron interacting with a magnetic field, with the simplest possible Feynman diagram. 05:48: ... is for the electron to emit a virtual photon just prior to absorbing the magnetic field photon, and then reabsorbing that virtual ... 09:49: The muons interact with the magnetic field and their own magnetic dipole axis, rotate like a top just before it falls. 05:48: ... is for the electron to emit a virtual photon just prior to absorbing the magnetic field photon, and then reabsorbing that virtual ... 09:41: At the Fermilab experiment, physicists send muons flying at nearly the speed of light around a 50 foot diameter magnetic tube.
	2021-03-23: Zeno's Paradox & The Quantum Zeno Effect 08:02: ... role in the photochemical reactions that give birds their ability to see magnetic fields - something we’ve talked about ...
	2021-02-17: Gravitational Wave Background Discovered? 00:00: ... stars tend to channel jets of high energy particles due to their intense magnetic fields they also rotate rapidly with the rotational axis offset from the ...
	2021-01-19: Can We Break the Universe? 15:23: ... way that changed depending on the direction and strength of a very weak magnetic ...
	2020-12-22: Navigating with Quantum Entanglement 02:22: ... that birds have a “magnetoreception” that they navigate by the Earth’s magnetic field came from the Russian zoologist Alexander von Middendorf back in ... 02:32: ... when German biologists Wolfgang Wiltschko and Friedrich Merkel applied magnetic fields to enclosures with European robins, preventing them from ... 02:48: How exactly birds detect magnetic fields remains an open question. 03:03: ... one: the idea that proposes birds can in a sense see the Earth’s magnetic field due to quantum weirdness happening inside their ... 03:19: Before we get into all the cool quantum stuff, a quick review on Earth’s magnetic field is in order. 04:12: This “declination” points towards the magnetic poles, which are offset from the true poles defined by Earth’s rotational axis. 04:52: In principle it’s easy to come up with ways to sense a magnetic field. 04:56: Magnetic fields exert a force on a moving or rotating charged particle. 05:00: An electron, for example, can be thought of as a spinning charge, and magnetic fields can cause that spin to flip direction. 05:08: ... like the one found in a compass needle aure ferromagnets, and their magnetic fields come from countless electrons with aligned ... 05:17: External magnetic fields tug on those electrons resulting in a force that can swivel the compass needle. 07:10: ... spin tends to stay fixed until disturbed by its environment. And Earth's magnetic field isn't strong enough to influence spin in that ... 07:27: They do that evenly in the absence of a magnetic field - 75% of the time in the triplet state and 25% in the singlet. 07:35: But even a weak magnetic field like the Earth's can affect the amount of time the radical pair spends in these states. 07:53: ... does the entanglement need to last in order to be influenced by Earth's magnetic field, and how does the simple slipping of electron spins go on to give ... 08:43: ... if the bird changes the orientation of its head relative to the Earth’s magnetic ... 08:59: That could lead to a true visual sense of magnetic field orientation. 09:15: ... have shown that it’s possible to affect cryptochromes with a weak magnetic field and get that characteristic change of rate of chemical ... 10:12: ... chemical reactions remember the quantum state, and so remember the magnetic ... 10:33: The team’s calculations showed that only a full quantum description of the process could produce the required sensitivity to magnetic fields. 10:40: ... for example, the valence electrons were just interacting due to their magnetic fields - so-called spin-spin interactions - rather than true entangled ... 02:22: ... that birds have a “magnetoreception” that they navigate by the Earth’s magnetic field came from the Russian zoologist Alexander von Middendorf back in ... 03:03: ... one: the idea that proposes birds can in a sense see the Earth’s magnetic field due to quantum weirdness happening inside their ... 03:19: Before we get into all the cool quantum stuff, a quick review on Earth’s magnetic field is in order. 04:52: In principle it’s easy to come up with ways to sense a magnetic field. 07:10: ... spin tends to stay fixed until disturbed by its environment. And Earth's magnetic field isn't strong enough to influence spin in that ... 07:27: They do that evenly in the absence of a magnetic field - 75% of the time in the triplet state and 25% in the singlet. 07:35: But even a weak magnetic field like the Earth's can affect the amount of time the radical pair spends in these states. 07:53: ... does the entanglement need to last in order to be influenced by Earth's magnetic field, and how does the simple slipping of electron spins go on to give the ... 08:43: ... if the bird changes the orientation of its head relative to the Earth’s magnetic field. ... 08:59: That could lead to a true visual sense of magnetic field orientation. 09:15: ... have shown that it’s possible to affect cryptochromes with a weak magnetic field and get that characteristic change of rate of chemical ... 10:12: ... chemical reactions remember the quantum state, and so remember the magnetic field. ... 07:27: They do that evenly in the absence of a magnetic field - 75% of the time in the triplet state and 25% in the singlet. 07:10: ... spin tends to stay fixed until disturbed by its environment. And Earth's magnetic field isn't strong enough to influence spin in that ... 08:59: That could lead to a true visual sense of magnetic field orientation. 02:32: ... when German biologists Wolfgang Wiltschko and Friedrich Merkel applied magnetic fields to enclosures with European robins, preventing them from navigating ... 02:48: How exactly birds detect magnetic fields remains an open question. 04:56: Magnetic fields exert a force on a moving or rotating charged particle. 05:00: An electron, for example, can be thought of as a spinning charge, and magnetic fields can cause that spin to flip direction. 05:08: ... like the one found in a compass needle aure ferromagnets, and their magnetic fields come from countless electrons with aligned ... 05:17: External magnetic fields tug on those electrons resulting in a force that can swivel the compass needle. 10:33: The team’s calculations showed that only a full quantum description of the process could produce the required sensitivity to magnetic fields. 10:40: ... for example, the valence electrons were just interacting due to their magnetic fields - so-called spin-spin interactions - rather than true entangled states - ... 04:56: Magnetic fields exert a force on a moving or rotating charged particle. 02:48: How exactly birds detect magnetic fields remains an open question. 05:17: External magnetic fields tug on those electrons resulting in a force that can swivel the compass needle. 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 09:35: Consider a magnetic material, made up of many little magnetic dipoles, like little bar magnets that can point in different directions. 09:56: But the individual magnetic particles interact with each other, they want to align with their neighbours. 10:13: However, if we cool the material down, the interactions between magnetic particles can start to come into play. 11:06: Spinning vectors and magnetic materials. 09:35: Consider a magnetic material, made up of many little magnetic dipoles, like little bar magnets that can point in different directions. 11:06: Spinning vectors and magnetic materials. 09:56: But the individual magnetic particles interact with each other, they want to align with their neighbours. 10:13: However, if we cool the material down, the interactions between magnetic particles can start to come into play. 09:56: But the individual magnetic particles interact with each other, they want to align with their neighbours.
	2020-09-28: Solving Quantum Cryptography 14:24: Last week we talked about a highly speculative idea - lifeforms inside stars, formed from cosmic strings and magnetic monopoles. 14:52: ... inside a star than outside - cosmic necklaces can be locked into the magnetic fields within the solar plasma so they don’t fall apart ... 15:28: John Momberg asks if this could all happen with electric monopoles, given that magnetic monopoles don’t exist. 15:35: Well, first let me say that magnetic monopoles may well exist - in fact mainstream grand unified theory candidates routinely predict them. 14:52: ... inside a star than outside - cosmic necklaces can be locked into the magnetic fields within the solar plasma so they don’t fall apart ... 14:24: Last week we talked about a highly speculative idea - lifeforms inside stars, formed from cosmic strings and magnetic monopoles. 15:28: John Momberg asks if this could all happen with electric monopoles, given that magnetic monopoles don’t exist. 15:35: Well, first let me say that magnetic monopoles may well exist - in fact mainstream grand unified theory candidates routinely predict them. 15:28: John Momberg asks if this could all happen with electric monopoles, given that magnetic monopoles don’t exist.
	2020-09-21: Could Life Evolve Inside Stars? 00:16: Oh, and here’s an extra crazy one - life composed of cosmic strings and magnetic monopoles, evolving in the hearts of stars. 01:03: ... and defects in the fabric of the universe - cosmic strings beaded with magnetic monopoles - may evolve into complex structures, and even life, within ... 01:28: What exactly are cosmic strings and magnetic monopoles? 01:38: Cosmic strings and magnetic monopoles are what we call topological defects. 02:31: ... can have exactly the same thing in magnetic materials, where the direction of the poles of the little magnetic ... 03:44: ... go through the possibilities: a 0-dimensional topological defect is a magnetic monopole - like the north or south pole of a bar magnet that somehow ... 05:44: With simple magnetic monopoles, the only possible necklace is an alternating series of north and south poles - or poles and anti-poles. 07:18: ... plasma and magnetic fields may stretch and break necklaces, which could reconfigure them ... 02:31: ... can have exactly the same thing in magnetic materials, where the direction of the poles of the little magnetic particles ... 03:44: ... go through the possibilities: a 0-dimensional topological defect is a magnetic monopole - like the north or south pole of a bar magnet that somehow lost its ... 00:16: Oh, and here’s an extra crazy one - life composed of cosmic strings and magnetic monopoles, evolving in the hearts of stars. 01:03: ... and defects in the fabric of the universe - cosmic strings beaded with magnetic monopoles - may evolve into complex structures, and even life, within ... 01:28: What exactly are cosmic strings and magnetic monopoles? 01:38: Cosmic strings and magnetic monopoles are what we call topological defects. 05:44: With simple magnetic monopoles, the only possible necklace is an alternating series of north and south poles - or poles and anti-poles. 01:03: ... and defects in the fabric of the universe - cosmic strings beaded with magnetic monopoles - may evolve into complex structures, and even life, within ... 00:16: Oh, and here’s an extra crazy one - life composed of cosmic strings and magnetic monopoles, evolving in the hearts of stars. 02:31: ... in magnetic materials, where the direction of the poles of the little magnetic particles changes across the ...
	2020-08-24: Can Future Colliders Break the Standard Model? 01:22: ... charged particles in a straight line, while the beam is focused by magnetic ... 01:32: ... particles are still accelerated by electric fields, but now a constant magnetic field causes the beam to spiral outwards from its central ... 07:03: And there are other anomalies like the muon’s magnetic moment. 07:25: ... particle accelerators like the sun or supernovae or quasars or galactic magnetic fields, which continuously spray the earth with particles at higher ... 01:32: ... particles are still accelerated by electric fields, but now a constant magnetic field causes the beam to spiral outwards from its central ... 01:22: ... charged particles in a straight line, while the beam is focused by magnetic fields. ... 07:25: ... particle accelerators like the sun or supernovae or quasars or galactic magnetic fields, which continuously spray the earth with particles at higher energies ... 07:03: And there are other anomalies like the muon’s magnetic moment.
	2020-08-17: How Stars Destroy Each Other 04:31: If the white dwarf has a strong magnetic field, the flow of gas from its companion is channeled by that field. 04:38: ... charged particles spiral along the magnetic field lines they emit synchrotron radiation, and bright X-ray light is ... 06:16: ... powerful magnetic field channels high energy particles into a jet that traces a circle ... 04:31: If the white dwarf has a strong magnetic field, the flow of gas from its companion is channeled by that field. 04:38: ... charged particles spiral along the magnetic field lines they emit synchrotron radiation, and bright X-ray light is emitted ... 06:16: ... powerful magnetic field channels high energy particles into a jet that traces a circle across ... 04:38: ... charged particles spiral along the magnetic field lines they emit synchrotron radiation, and bright X-ray light is emitted as ...
	2020-07-08: Does Antimatter Explain Why There's Something Rather Than Nothing? 06:00: ... electrically neutral and so are hard to even store using electric and magnetic ... 08:00: ... anti-protons are trapped by a combination of electric and magnetic fields in a so-called Penning ... 08:50: ... anti-hydrogen is electrically neutral, it does have a small magnetic moment - like a tiny bar magnet. ALPHA introduces a new magnetic field ... 09:19: ... mass and charge of the particles, their orbital angular momentum, their magnetic and electric dipole moments, and even the strength of the coupling ... 08:50: ... a small magnetic moment - like a tiny bar magnet. ALPHA introduces a new magnetic field that forces the anti-matter to the center of the chamber. In this way ... 06:00: ... electrically neutral and so are hard to even store using electric and magnetic fields. ... 08:00: ... anti-protons are trapped by a combination of electric and magnetic fields in a so-called Penning ... 08:50: ... anti-hydrogen is electrically neutral, it does have a small magnetic moment - like a tiny bar magnet. ALPHA introduces a new magnetic field that ...
	2020-06-08: Can Viruses Travel Between Planets? 07:26: ... lifted to the very edge of an atmosphere with the help of the planet’s magnetic field and then swept into interplanetary or even interstellar space by ...
	2020-05-27: Does Gravity Require Extra Dimensions? 10:08: The experiment is now typically done in a vacuum, with precise temperature control and electrostatic and magnetic shielding.
	2020-04-28: Space Time Livestream: Ask Matt Anything 00:00: ... on the edge where your giant streamers of plasma are channeled by magnetic fields it's a cool cool toy now but what have I actually been doing ...
	2020-04-14: Was the Milky Way a Quasar? 11:16: ... by electrons, but in this case, the electrons are accelerated by magnetic fields and are emitting what’s known as synchrotron ...
	2020-03-24: How Black Holes Spin Space Time 10:51: ... universe. It’s the Blandford-Znajek process. In this case you have a magnetic field produced by the flow of material around the black hole in an ...
	2020-03-16: How Do Quantum States Manifest In The Classical World? 08:44: ... hasn't collapsed. Here’s more evidence, even with the vertically-aligned magnetic fields, which only affect the vertical component of the electron’s spin, ... 11:48: ... some extent the way you set up the experiment - whether you align your magnetic field vertically or horizontally. But ultimately they are states that ... 08:44: ... hasn't collapsed. Here’s more evidence, even with the vertically-aligned magnetic fields, which only affect the vertical component of the electron’s spin, we ...
	2020-02-11: Are Axions Dark Matter? 08:05: ... an axion turning into a photon - typically in the presence of a strong magnetic field. And photons can turn into axions in a similar ... 08:23: ... opaque wall. It goes like this: a light is passed through a strong magnetic field and then blocked by a metal wall. But some photons get converted ... 08:53: One issue may be that we just can’t make sufficiently strong artificial magnetic fields. 08:58: ... axions. CAST forms the detector part of the apparatus and uses strong magnetic fields of its own to try to turn those axions back into detectable ... 09:45: ... are other spacey tests for axions. Magnetars - highly magnetic pulsars - and quasars may convert some of their own gamma ray output ... 08:05: ... an axion turning into a photon - typically in the presence of a strong magnetic field. And photons can turn into axions in a similar ... 08:23: ... opaque wall. It goes like this: a light is passed through a strong magnetic field and then blocked by a metal wall. But some photons get converted to ... 08:53: One issue may be that we just can’t make sufficiently strong artificial magnetic fields. 08:58: ... axions. CAST forms the detector part of the apparatus and uses strong magnetic fields of its own to try to turn those axions back into detectable photons. No ... 09:45: ... rays get converted back and forth between axions and photons by the magnetic fields of entire galaxies. That makes them invisible for part of their journey, ...
	2020-01-06: How To Detect a Neutrino 03:09: ♪ ♪ More magnetic fields are used to sort the positively charged pion particles from the debris ♪ ♪ and focus *them* into a beam.
	2019-11-11: Does Life Need a Multiverse to Exist? 13:28: ... in Earth's core, which may help explain the strength of our protective magnetic ... 13:56: The result: more iron, less rock, more magnetic field. 13:28: ... in Earth's core, which may help explain the strength of our protective magnetic field. ... 13:56: The result: more iron, less rock, more magnetic field.
	2019-11-04: Why We Might Be Alone in the Universe 05:59: ... in a molten metal outer core, and this motion generates a powerful magnetic field that protects Earth from dangerous space radiation and solar ...
	2019-09-23: Is Pluto a Planet? 16:47: The magnetic field that it does have comes from the interaction of the solar wind with its super thick atmosphere.
	2019-09-16: Could We Terraform Mars? 03:39: ... than Earth’s core, solidifying long ago and shutting down its global magnetic ... 03:49: Earth’s magnetic field protects us from the solar wind, as we saw in a recent episode. 13:10: We canNOT restart Mars’ magnetic field – to do that we’d have to re-melt the entire core. 13:16: But we can try to build an external magnetic shield. 16:05: ... well as the episode on the exciting possibility that the North and South magnetic poles may be about to ... 17:59: For now, let's move on to the possible flipping of Earth's North and South magnetic poles. 18:06: ... points out that while Venus lacks an Earth-type intrinsic magnetic field, the solar wind striking its atmosphere creates an induced ... 18:23: Electrical currents are induced and these produce a magnetic field that pushes back against the Sun's magnetic field. 18:29: ... magnetic force-shield isn't nearly as strong as Earth's, however, so our Venusian ... 18:38: ... many viewers noted, what we currently call the north magnetic pole is technically a south magnetic pole - as in, what we would call ... 18:50: You know how the magnetic north pole of a bar magnet is attracted to the south pole of a second bar magnet? 18:56: Well, your compass's north pole is attracted to geographic north - which means geographic north must correspond to a magnetic south pole. 19:06: Nolan Westrich, while laughing in Australian, notes that with the flipping of the magnetic poles it will be America's turn to be upside down. 19:15: ... given that the northern hemisphere is currently the magnetic south, I think that means that North America, Europe, and most of Asia ... 18:38: ... a south magnetic pole - as in, what we would call the south pole of a magnetic dipole or a bar ... 03:39: ... than Earth’s core, solidifying long ago and shutting down its global magnetic field. ... 03:49: Earth’s magnetic field protects us from the solar wind, as we saw in a recent episode. 13:10: We canNOT restart Mars’ magnetic field – to do that we’d have to re-melt the entire core. 18:06: ... points out that while Venus lacks an Earth-type intrinsic magnetic field, the solar wind striking its atmosphere creates an induced magnetic field ... 18:23: Electrical currents are induced and these produce a magnetic field that pushes back against the Sun's magnetic field. 03:49: Earth’s magnetic field protects us from the solar wind, as we saw in a recent episode. 18:29: ... magnetic force-shield isn't nearly as strong as Earth's, however, so our Venusian floating ... 18:50: You know how the magnetic north pole of a bar magnet is attracted to the south pole of a second bar magnet? 18:38: ... many viewers noted, what we currently call the north magnetic pole is technically a south magnetic pole - as in, what we would call the ... 16:05: ... well as the episode on the exciting possibility that the North and South magnetic poles may be about to ... 17:59: For now, let's move on to the possible flipping of Earth's North and South magnetic poles. 19:06: Nolan Westrich, while laughing in Australian, notes that with the flipping of the magnetic poles it will be America's turn to be upside down. 13:16: But we can try to build an external magnetic shield. 18:56: Well, your compass's north pole is attracted to geographic north - which means geographic north must correspond to a magnetic south pole. 19:15: ... given that the northern hemisphere is currently the magnetic south, I think that means that North America, Europe, and most of Asia have ... 18:56: Well, your compass's north pole is attracted to geographic north - which means geographic north must correspond to a magnetic south pole.
	2019-09-03: Is Earth's Magnetic Field Reversing? 00:00: Earth’s magnetic field protects us from deadly space radiation. 00:24: ... of magnetic force, forged by currents in the planet’s molten core, erupt from the ... 00:38: Magnetic fields exert a force on moving charged particles, causing them to spiral around those force lines. 00:55: Our magnetic field deflects the worst of these. 01:21: The magnetic field is currently undergoing rapid changes, possibly signaling the imminent flipping of its polarity. 01:56: Magnetic materials like iron often form with their natural fields aligned with Earth’s field. 02:02: We can track the direction of Earth’s magnetic field in sedimentary layers and in old volcanic flows. 02:42: Except for the fact that the magnetic field DOES seem to be acting strangely lately. 02:54: And for that we need to understand the Earth’s magnetic field. 02:58: ... we think of magnetic fields being generated in two way: In magnetic materials like iron, the ... 03:15: Alternatively, flows of many charged particles like electrons – so electrical currents - can produce magnetic fields. 03:26: But Earth’s interior is not intrinsically magnetic – its too hot for the iron atoms in the core to spontaneously align. 03:41: How, then, does the Earth generate such a gigantic and well-organized dipole magnetic field? 05:10: ... all of this motion that together produces Earth’s magnetic field through a process called the dynamo effect – or so most scientists ... 05:42: ... key is that the dynamo effect doesn’t really create a magnetic field from scratch – instead it amplifies, organizes, and sustains an ... 05:52: I’ll come back to where that initial magnetic field comes from. 06:05: Conductors have this cool property that they drag magnetic fields with them. 06:10: So if the entire core is rotating with the Earth then the magnetic field will also rotate. 06:21: As a result, the starting magnetic field gets wound up into rings around the axis of rotation – into a torus shape. 06:40: Those flows grab hold of our toroidal magnetic field and twist it up further - into many little loops. 06:47: Those loops form magnetic tubes around Earth’s rotational axis. 07:09: But where does that initial magnetic field come from in the first place. 07:50: In fact Earth’s magnetic field is a highly dynamic beast. 08:06: ... magnetic north pole is currently moving at around 60 km per year around 5 degrees ... 08:27: OK, so what’s all this about the magnetic field flipping over? 08:30: In fact, HOW can it flip? – surely the direction of the magnetic field depends on the direction Earth is spinning. 08:37: ... electrical currents, which in turn depend on the direction of small magnetic loops generated by these helical convection ... 08:50: ... fact, we expect that if the magnetic field were switched off entirely, it would reestablish itself randomly, ... 09:12: Earth’s magnetic field isn’t necessarily switched off, but it’s scrambled in some way. 09:51: ... in which the chaotic motion of outer-core fluid causes a tangling of magnetic field lines and a global drop in field ... 10:57: ... international World Magnetic Model is a global maps of Earth’s magnetic field updated every 5 years – ... 11:10: ... WMM scientists found the north magnetic pole was moving so quickly that they updated nearly a year early – at ... 12:06: The field also becomes very messy – with mini north and south magnetic poles popping up across the surface of the planet. 12:24: ... scientists have a pretty good idea, and think that Earth’s magnetic field is likely to hold out for our lifetimes – and those of some ... 13:04: ... made of millions of refrigerator magnets to protect us once the Earth’s magnetic field ... 00:00: Earth’s magnetic field protects us from deadly space radiation. 00:55: Our magnetic field deflects the worst of these. 01:21: The magnetic field is currently undergoing rapid changes, possibly signaling the imminent flipping of its polarity. 02:02: We can track the direction of Earth’s magnetic field in sedimentary layers and in old volcanic flows. 02:42: Except for the fact that the magnetic field DOES seem to be acting strangely lately. 02:54: And for that we need to understand the Earth’s magnetic field. 03:41: How, then, does the Earth generate such a gigantic and well-organized dipole magnetic field? 05:10: ... all of this motion that together produces Earth’s magnetic field through a process called the dynamo effect – or so most scientists ... 05:42: ... key is that the dynamo effect doesn’t really create a magnetic field from scratch – instead it amplifies, organizes, and sustains an existing ... 05:52: I’ll come back to where that initial magnetic field comes from. 06:10: So if the entire core is rotating with the Earth then the magnetic field will also rotate. 06:21: As a result, the starting magnetic field gets wound up into rings around the axis of rotation – into a torus shape. 06:40: Those flows grab hold of our toroidal magnetic field and twist it up further - into many little loops. 07:09: But where does that initial magnetic field come from in the first place. 07:50: In fact Earth’s magnetic field is a highly dynamic beast. 08:27: OK, so what’s all this about the magnetic field flipping over? 08:30: In fact, HOW can it flip? – surely the direction of the magnetic field depends on the direction Earth is spinning. 08:50: ... fact, we expect that if the magnetic field were switched off entirely, it would reestablish itself randomly, with ... 09:12: Earth’s magnetic field isn’t necessarily switched off, but it’s scrambled in some way. 09:51: ... in which the chaotic motion of outer-core fluid causes a tangling of magnetic field lines and a global drop in field ... 10:57: ... international World Magnetic Model is a global maps of Earth’s magnetic field updated every 5 years – in the past that’s been frequent enough to ... 12:24: ... scientists have a pretty good idea, and think that Earth’s magnetic field is likely to hold out for our lifetimes – and those of some generations ... 13:04: ... made of millions of refrigerator magnets to protect us once the Earth’s magnetic field ... 00:55: Our magnetic field deflects the worst of these. 08:30: In fact, HOW can it flip? – surely the direction of the magnetic field depends on the direction Earth is spinning. 13:04: ... made of millions of refrigerator magnets to protect us once the Earth’s magnetic field fails. ... 08:27: OK, so what’s all this about the magnetic field flipping over? 09:12: Earth’s magnetic field isn’t necessarily switched off, but it’s scrambled in some way. 09:51: ... in which the chaotic motion of outer-core fluid causes a tangling of magnetic field lines and a global drop in field ... 00:00: Earth’s magnetic field protects us from deadly space radiation. 10:57: ... international World Magnetic Model is a global maps of Earth’s magnetic field updated every 5 years – in the past that’s been frequent enough to account for ... 00:38: Magnetic fields exert a force on moving charged particles, causing them to spiral around those force lines. 02:58: ... we think of magnetic fields being generated in two way: In magnetic materials like iron, the sum ... 03:15: Alternatively, flows of many charged particles like electrons – so electrical currents - can produce magnetic fields. 06:05: Conductors have this cool property that they drag magnetic fields with them. 00:38: Magnetic fields exert a force on moving charged particles, causing them to spiral around those force lines. 00:24: ... of magnetic force, forged by currents in the planet’s molten core, erupt from the surface ... 08:37: ... electrical currents, which in turn depend on the direction of small magnetic loops generated by these helical convection ... 01:56: Magnetic materials like iron often form with their natural fields aligned with Earth’s field. 02:58: ... we think of magnetic fields being generated in two way: In magnetic materials like iron, the sum total of the tiny magnetic fields of their ... 10:57: ... international World Magnetic Model is a global maps of Earth’s magnetic field updated every 5 years – in ... 08:06: ... magnetic north pole is currently moving at around 60 km per year around 5 degrees south ... 11:10: ... WMM scientists found the north magnetic pole was moving so quickly that they updated nearly a year early – at the ... 08:50: ... entirely, it would reestablish itself randomly, with the north and south magnetic poles aligned either one way or the ... 12:06: The field also becomes very messy – with mini north and south magnetic poles popping up across the surface of the planet. 08:50: ... entirely, it would reestablish itself randomly, with the north and south magnetic poles aligned either one way or the ... 12:06: The field also becomes very messy – with mini north and south magnetic poles popping up across the surface of the planet. 06:47: Those loops form magnetic tubes around Earth’s rotational axis.
	2019-08-06: What Caused the Big Bang? 01:04: Another problem fixed by inflation is the absence of magnetic monopoles. 05:16: A familiar example is the magnetic field. The stronger the field, the more it pulls or pushes. 05:45: ... all energy besides whatever is bound up in particles. For example, a magnetic field will quickly fade away if we take away the electric currents that ... 05:16: A familiar example is the magnetic field. The stronger the field, the more it pulls or pushes. 05:45: ... all energy besides whatever is bound up in particles. For example, a magnetic field will quickly fade away if we take away the electric currents that ... 01:04: Another problem fixed by inflation is the absence of magnetic monopoles.
	2019-06-17: How Black Holes Kill Galaxies 06:33: ... through the surrounding galaxy or its channeled into jets by powerful magnetic ...
	2019-05-09: Why Quantum Computing Requires Quantum Cryptography 04:58: Polarization defines the direction that its electric and magnetic fields … wave. 16:09: What was imaged was light escaping from the photon sphere that was produced a the magnetically driven jet.
	2019-05-01: The Real Science of the EHT Black Hole 05:39: It’s also blasting out a jet of energetic particles, channeled by the intense magnetic fields around the black hole. 07:59: Synchrotron results from electrons spiraling in magnetic fields. 08:55: ... simulation that weaves in all of the physics of fluid flow and magnetic fields, in this case with the addition of the warped spacetime of a ... 05:39: It’s also blasting out a jet of energetic particles, channeled by the intense magnetic fields around the black hole. 07:59: Synchrotron results from electrons spiraling in magnetic fields. 08:55: ... simulation that weaves in all of the physics of fluid flow and magnetic fields, in this case with the addition of the warped spacetime of a black hole ...
	2019-03-06: The Impossibility of Perpetual Motion Machines 10:45: Alex Taylor has an especially cool dynamo device in which the masses are contained in a magnetic field. 13:47: ... electrons either bumping into other charged particles or circling in magnetic fields Fortunately we can model that stuff pretty ... 10:45: Alex Taylor has an especially cool dynamo device in which the masses are contained in a magnetic field. 13:47: ... electrons either bumping into other charged particles or circling in magnetic fields Fortunately we can model that stuff pretty ...
	2019-01-16: Our Antimatter, Mirrored, Time-Reversed Universe 01:48: ... an array of cobalt-60 atoms in a magnetic field, the cobalt nuclei have angular momenta that will align with a ... 03:02: ... atoms have negatively charged nuclei which means their nuclear magnetic fields point in the opposite direction to regular matter relative to ... 01:48: ... an array of cobalt-60 atoms in a magnetic field, the cobalt nuclei have angular momenta that will align with a magnetic ... 03:02: ... direction to regular matter relative to their angular momentum the magnetic field in our clock will align antimatter nuclei in the opposite direction to ...
	2018-12-12: Quantum Physics in a Mirror Universe 00:02: ... spin which means it's possible to align the spin of the nucleus using a magnetic field so Wuan team applied a magnetic field to our layer of cobalt-60 ...
	2018-11-14: Supersymmetric Particle Found? 03:52: ... explosions, gamma ray bursts, black hole magnetic fields are all expected to blast high energy particles like electrons ...
	2018-11-07: Why String Theory is Right 14:26: Uri Nation asks about the photons that mediate the magnetic field or the contact force between two bodies.
	2018-08-23: How Will the Universe End? 13:46: OK, onto your comments for last week's episode on the most accurate prediction in all of science, the anomalous magnetic moment of the electron.
	2018-08-15: Quantum Theory's Most Incredible Prediction 01:53: ... measuring the G factor, or in simple English, measuring the anomalous magnetic dipole moment of the ... 02:10: What is the anomalous magnetic dipole moment? 02:14: Well, it's just like the regular magnetic dipole moment but more anomalous. 02:21: Let's break down these magnetic dipole moment thing. 02:25: It has a dipole magnetic field, basically meaning it has a north and south pole. 02:33: If we put a bar magnet in a second external magnetic field, it'll feel a torque, a force causing it to rotate to align with that field. 02:42: The tendency of a dipole magnet to rotate in an external magnetic field is its magnetic dipole moment. 02:50: ... with a dipole magnetic field has a magnetic dipole moment is basically a measure of how much it ... 03:03: Magnetic fields are produced by moving electric charges. 03:16: But in the case of a bar magnet, the source of its magnetic field is a bit weirder. 03:21: It mostly comes from the summed dipole magnetic fields of individual electrons in the outer shells of its atoms. 04:12: Despite not being the same as classical rotation, this quantum spin does grant electrons a dipole magnetic field. 04:20: So electrons have a magnetic dipole moment, meaning they feel magnetic fields and act as little bar magnets. 04:27: Electrons in atoms feel the magnetic fields produced by their own orbits around the atom. 04:57: It also gives you completely the wrong answer if you try to calculate the electron's magnetic moment. 05:09: ... fact, weirdly, if you measure the magnetic dipole moment of an electron, you get almost exactly twice the value ... 05:23: This difference between the quantum versus classical magnetic moments for the electron is called the G factor. 06:45: This messiness messes with the interaction of the electron and the magnetic field to shift the G factor slightly. 07:02: And this is the anomalous magnetic dipole moment. 08:36: An electron encounters a real photon that could represent an external magnetic field. 09:04: ... say, the overall strength of an electron's interaction with the magnetic field when we calculate the electrons magnetic dipole moment and it's G ... 10:45: One way to do it is to watch the way electrons process in the constant magnetic field of a cyclotron, a type of particle accelerator. 10:54: Electron spin axes are always slightly misaligned with an external magnetic field, due to quantum uncertainty in the spin direction. 11:41: So it's really the relationship between the electron magnetic moment and the fine structure constant that we're verifying. 14:23: Andrea Smith asks whether the Suns million Kelvin corona temperature is caused by magnetic reconnection. 14:48: It's pretty firmly established that energy must be pumped into the corona by magnetic fields. 14:59: Magnetic fields can do the job in two ways. 15:02: One is this magnetic reconnection thing. 15:05: ... magnetic loops extending from the surface break and reconnect into different ... 15:13: Another possible mechanism is through turbulence in waves generated by the rapid motion of magnetic fields. 01:53: ... measuring the G factor, or in simple English, measuring the anomalous magnetic dipole moment of the ... 02:10: What is the anomalous magnetic dipole moment? 02:14: Well, it's just like the regular magnetic dipole moment but more anomalous. 02:21: Let's break down these magnetic dipole moment thing. 02:42: The tendency of a dipole magnet to rotate in an external magnetic field is its magnetic dipole moment. 02:50: ... with a dipole magnetic field has a magnetic dipole moment is basically a measure of how much it would interact with an ... 04:20: So electrons have a magnetic dipole moment, meaning they feel magnetic fields and act as little bar magnets. 05:09: ... fact, weirdly, if you measure the magnetic dipole moment of an electron, you get almost exactly twice the value you'd ... 07:02: And this is the anomalous magnetic dipole moment. 09:04: ... interaction with the magnetic field when we calculate the electrons magnetic dipole moment and it's G ... 01:53: ... measuring the G factor, or in simple English, measuring the anomalous magnetic dipole moment of the ... 02:10: What is the anomalous magnetic dipole moment? 02:14: Well, it's just like the regular magnetic dipole moment but more anomalous. 02:21: Let's break down these magnetic dipole moment thing. 02:42: The tendency of a dipole magnet to rotate in an external magnetic field is its magnetic dipole moment. 02:50: ... with a dipole magnetic field has a magnetic dipole moment is basically a measure of how much it would interact with an external ... 04:20: So electrons have a magnetic dipole moment, meaning they feel magnetic fields and act as little bar magnets. 05:09: ... fact, weirdly, if you measure the magnetic dipole moment of an electron, you get almost exactly twice the value you'd expect for ... 07:02: And this is the anomalous magnetic dipole moment. 09:04: ... interaction with the magnetic field when we calculate the electrons magnetic dipole moment and it's G ... 02:25: It has a dipole magnetic field, basically meaning it has a north and south pole. 02:33: If we put a bar magnet in a second external magnetic field, it'll feel a torque, a force causing it to rotate to align with that field. 02:42: The tendency of a dipole magnet to rotate in an external magnetic field is its magnetic dipole moment. 02:50: ... with a dipole magnetic field has a magnetic dipole moment is basically a measure of how much it would ... 03:16: But in the case of a bar magnet, the source of its magnetic field is a bit weirder. 04:12: Despite not being the same as classical rotation, this quantum spin does grant electrons a dipole magnetic field. 06:45: This messiness messes with the interaction of the electron and the magnetic field to shift the G factor slightly. 08:36: An electron encounters a real photon that could represent an external magnetic field. 09:04: ... say, the overall strength of an electron's interaction with the magnetic field when we calculate the electrons magnetic dipole moment and it's G ... 10:45: One way to do it is to watch the way electrons process in the constant magnetic field of a cyclotron, a type of particle accelerator. 10:54: Electron spin axes are always slightly misaligned with an external magnetic field, due to quantum uncertainty in the spin direction. 02:25: It has a dipole magnetic field, basically meaning it has a north and south pole. 02:33: If we put a bar magnet in a second external magnetic field, it'll feel a torque, a force causing it to rotate to align with that field. 03:03: Magnetic fields are produced by moving electric charges. 03:21: It mostly comes from the summed dipole magnetic fields of individual electrons in the outer shells of its atoms. 04:20: So electrons have a magnetic dipole moment, meaning they feel magnetic fields and act as little bar magnets. 04:27: Electrons in atoms feel the magnetic fields produced by their own orbits around the atom. 14:48: It's pretty firmly established that energy must be pumped into the corona by magnetic fields. 14:59: Magnetic fields can do the job in two ways. 15:13: Another possible mechanism is through turbulence in waves generated by the rapid motion of magnetic fields. 04:27: Electrons in atoms feel the magnetic fields produced by their own orbits around the atom. 15:05: ... magnetic loops extending from the surface break and reconnect into different forms, ... 04:57: It also gives you completely the wrong answer if you try to calculate the electron's magnetic moment. 11:41: So it's really the relationship between the electron magnetic moment and the fine structure constant that we're verifying. 05:23: This difference between the quantum versus classical magnetic moments for the electron is called the G factor. 14:23: Andrea Smith asks whether the Suns million Kelvin corona temperature is caused by magnetic reconnection. 15:02: One is this magnetic reconnection thing.
	2018-08-01: How Close To The Sun Can Humanity Get? 01:22: Magnetic storms driving a constant stream of energy and potentially, destructive particles. 02:29: ... received electric shocks from currents induced by Earth's compressed magnetic ... 03:51: It'll directly probe the sun's electromagnetic field and will connect the sun's magnetic activity with the sources of the solar wind. 04:00: It will also measure the outward flow of the magnetic field through the pointing flux, as well as the plasma density and electron temperature. 03:51: It'll directly probe the sun's electromagnetic field and will connect the sun's magnetic activity with the sources of the solar wind. 02:29: ... received electric shocks from currents induced by Earth's compressed magnetic field. ... 04:00: It will also measure the outward flow of the magnetic field through the pointing flux, as well as the plasma density and electron temperature. 01:22: Magnetic storms driving a constant stream of energy and potentially, destructive particles.
	2018-06-27: How Asteroid Mining Will Save Earth 09:15: There are also proposals to scrape regolith, asteroid dust, from the surface, or to magnetically harvest loose surface metals.
	2018-06-13: What Survives Inside A Black Hole? 08:30: But what about the magnetic part of electromagnetism, and what about angular momentum? 08:38: A changing electric field produces a magnetic field. 08:40: And so if the black hole is spinning or racing past you, you'll see that magnetic field. 08:38: A changing electric field produces a magnetic field. 08:40: And so if the black hole is spinning or racing past you, you'll see that magnetic field.
	2018-04-25: Black Hole Swarms 06:25: One we expect to be common in the galactic core are magnetic cataclysmic variables, also called polars. 06:32: Polars are a bit like X-ray binaries, except instead of a black hole or a neutron star, you have a white dwarf with a powerful magnetic field. 06:39: ... magnetic fields act like a dam, allowing gas from the companion star to build up ... 06:25: One we expect to be common in the galactic core are magnetic cataclysmic variables, also called polars. 06:32: Polars are a bit like X-ray binaries, except instead of a black hole or a neutron star, you have a white dwarf with a powerful magnetic field. 06:39: ... magnetic fields act like a dam, allowing gas from the companion star to build up and ...
	2018-04-04: The Unruh Effect 09:06: A charged particle accelerating in a magnetic field emits radiation, bremsstrahlung radiation. 09:13: An inertial observer sees the charged particle itself radiating, its energy extracted from the magnetic field. 09:06: A charged particle accelerating in a magnetic field emits radiation, bremsstrahlung radiation. 09:13: An inertial observer sees the charged particle itself radiating, its energy extracted from the magnetic field. 09:06: A charged particle accelerating in a magnetic field emits radiation, bremsstrahlung radiation.
	2018-01-31: Kronos: Devourer Of Worlds 08:08: ... but most ideas involve increasing the rate of the solar wind while also magnetically driving the outflow towards the poles so Earth doesn't get ...
	2018-01-10: What Do Stars Sound Like? 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. 12:26: Felix Schneider asks how electromagnetic radiation can be focused by a magnetic field. 12:39: In fact, the magnetic field of a gamma ray burst focuses charged particles-- electrons and the nuclei of the exploding star. 12:56: The charged particles spiral around the axial magnetic fields and emit photons as they do. 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. 12:26: Felix Schneider asks how electromagnetic radiation can be focused by a magnetic field. 12:39: In fact, the magnetic field of a gamma ray burst focuses charged particles-- electrons and the nuclei of the exploding star. 12:56: The charged particles spiral around the axial magnetic fields and emit photons as they do.
	2017-12-20: Extinction by Gamma-Ray Burst 03:08: In that case, the powerful magnetic fields can channel the explosion into narrow jets that massively focus and amplify the blast.
	2017-11-22: Suicide Space Robots 08:44: ... system in 2012, it passed the heliopause-- the boundary where the sun's magnetic field and solar wind give way to the ambient environment of the Milky ...
	2017-10-11: Absolute Cold 01:00: Using lasers and magnetic fields, we've now managed to cool certain substances to less than a billionth of a Kelvin.
	2017-10-04: When Quasars Collide STJC 04:54: When a black hole feeds, the vortex of infalling plasma-- the accretion disk-- can produce a powerful magnetic field. 05:08: Those jets can blast through the surrounding galaxy and beyond, carrying their magnetic fields with them. 05:15: The radio light seen here is from electrons spiraling in those magnetic fields, so-called synchrotron radiation. 04:54: When a black hole feeds, the vortex of infalling plasma-- the accretion disk-- can produce a powerful magnetic field. 05:08: Those jets can blast through the surrounding galaxy and beyond, carrying their magnetic fields with them. 05:15: The radio light seen here is from electrons spiraling in those magnetic fields, so-called synchrotron radiation.
	2017-09-28: Are the Fundamental Constants Changing? 05:17: Now, quantum spin gives electrons what we call a magnetic moment. 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. 05:31: These same electrons are also orbiting the atomic nucleus, and that motion generates its own magnetic field. 05:38: ... magnetic fields produced by an electron's spin and by its orbital motion actually ... 05:31: These same electrons are also orbiting the atomic nucleus, and that motion generates its own magnetic field. 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. 05:38: ... magnetic fields produced by an electron's spin and by its orbital motion actually ... 05:17: Now, quantum spin gives electrons what we call a magnetic moment.
	2017-09-13: Neutron Stars Collide in New LIGO Signal? 02:39: ... stars can rotate up to thousands of times per second and have enormous magnetic fields that result in jets of near light speed particles that sweep ...
	2017-08-16: Extraterrestrial Superstorms 08:10: ... studying cloud chemistry, a magnetometer for measuring Jupiter's intense magnetic field, and a four-color wide-field ...
	2017-06-28: The First Quantum Field Theory 09:40: ... electron energy levels due to electron spins-- spins interacting with magnetic fields in the so-called hyperfine splitting or spins interacting with ...
	2017-06-21: Anti-Matter and Quantum Relativity 02:47: For example, an electron's spin causes them to align themselves with magnetic fields, just like a rotating electric charge would. 04:26: But when a magnetic field is present, spin direction becomes very important. 02:47: For example, an electron's spin causes them to align themselves with magnetic fields, just like a rotating electric charge would.
	2017-05-17: Martian Evolution 07:20: These bombard the surface due to the sparse atmosphere and the absence of a protective magnetic field.
	2017-04-19: The Oh My God Particle 06:00: We build artificial ones on Earth using giant rings and powerful magnetic fields. 06:18: When a star explodes, the expanding shock wave carries a strong magnetic field. 06:41: But they may come from magnetic acceleration in quasars, or perhaps they're blasted out in gamma ray bursts. 08:29: Part of the challenge in understanding cosmic rays is that our atmosphere and magnetic field shield the surface of the earth so well. 06:41: But they may come from magnetic acceleration in quasars, or perhaps they're blasted out in gamma ray bursts. 06:18: When a star explodes, the expanding shock wave carries a strong magnetic field. 08:29: Part of the challenge in understanding cosmic rays is that our atmosphere and magnetic field shield the surface of the earth so well. 06:00: We build artificial ones on Earth using giant rings and powerful magnetic fields.
	2017-03-15: Time Crystals! 04:13: Spins in nearby atoms like to line up with each other due to interacting magnetic fields. 04:25: This is the same effect that results in magnetic materials. 04:13: Spins in nearby atoms like to line up with each other due to interacting magnetic fields. 04:25: This is the same effect that results in magnetic materials.
	2017-02-22: The Eye of Sauron Reveals a Forming Solar System! 08:54: By the way, the third star in the system is a flare star, violently fluctuating due to magnetic storms on its surface.
	2017-01-25: Why Quasars are so Awesome 05:07: This may be due to the magnetic field of a rapidly rotating black hole, but the jury is still out.
	2017-01-19: The Phantom Singularity 16:22: ... what I'd expect when you generate temperature differentials and large magnetic fields around a very sensitive position measuring ...
	2017-01-04: How to See Black Holes + Kugelblitz Challenge Answer 03:29: This has enabled EHT to map the strange magnetic field structures around the Sag A star black hole.
	2016-11-30: Pilot Wave Theory and Quantum Realism 14:25: Sebastian Lopez asks how are the magnetic fields of neutron stars created. 14:30: Well, to create and sustain a magnetic field, you need some charge that's moving or spinning in some way. 15:06: With their extreme rotation rates, neutron stars support electric currents sufficient for magnetic fields of up to 100 million tesla. 14:30: Well, to create and sustain a magnetic field, you need some charge that's moving or spinning in some way. 14:25: Sebastian Lopez asks how are the magnetic fields of neutron stars created. 15:06: With their extreme rotation rates, neutron stars support electric currents sufficient for magnetic fields of up to 100 million tesla.
	2016-11-16: Strange Stars 02:23: Its immense magnetic field drives jets of material at extreme speeds.
	2016-11-02: Quantum Vortices and Superconductivity + Drake Equation Challenge Answers 02:11: ... how differences in topology were the culprit behind a strange quantized magnetic field observed in the mysterious "quantum hole effect." These findings ...
	2016-10-19: The First Humans on Mars 03:13: Mars's thin atmosphere and lack of magnetic field make shielding critical, especially for a permanent settlement. 06:32: ... we'll will build entire centrifuge cities levitating on superconducting magnetic rails and rotating once every few ... 03:13: Mars's thin atmosphere and lack of magnetic field make shielding critical, especially for a permanent settlement. 06:32: ... we'll will build entire centrifuge cities levitating on superconducting magnetic rails and rotating once every few ...
	2016-09-29: Life on Europa? 01:51: ... that produce those plumes and then discolored by Jupiter's intense magnetic ... 07:50: ... imaging and infrared scans, probe the interior with radar and magnetic mapping, and use a variety of instruments to sniff out the chemical ... 01:51: ... that produce those plumes and then discolored by Jupiter's intense magnetic field. ... 07:50: ... imaging and infrared scans, probe the interior with radar and magnetic mapping, and use a variety of instruments to sniff out the chemical composition ...
	2016-09-21: Quantum Entanglement and the Great Bohr-Einstein Debate 08:05: Polarization is just the alignment of a photon's electric and magnetic fields.
	2016-07-27: The Quantum Experiment that Broke Reality 12:25: Juno will figure that out by carefully mapping Jupiter's gravitational and magnetic fields.
	2016-07-06: Juno to Reveal Jupiter's Violent Past 01:52: The conductivity of metallic hydrogen is thought to result in the enormous electric currents that produce Jupiter's prodigious magnetic field.
	2016-03-23: How Cosmic Inflation Flattened the Universe 13:00: Although the magnetic field of a spinning black hole can also play a part here.
	2016-02-03: Will Mars or Venus Kill You First? 01:23: ... its once spinning iron core to a halt and essentially turning off its magnetic ... 04:35: Both thick atmosphere and strong magnetic field are excellent protection against this stuff. 05:27: This is when a magnetic storm on the sun's surface sends out a blast of extremely high energy particles, most notably protons and electrons. 08:00: Venus does not generate its own magnetic field. 08:03: ... the interaction of the sun's magnetic field with Venus's think atmosphere actually induces something of a ... 01:23: ... its once spinning iron core to a halt and essentially turning off its magnetic field. ... 04:35: Both thick atmosphere and strong magnetic field are excellent protection against this stuff. 08:00: Venus does not generate its own magnetic field. 08:03: ... the interaction of the sun's magnetic field with Venus's think atmosphere actually induces something of a protective ... 05:27: This is when a magnetic storm on the sun's surface sends out a blast of extremely high energy particles, most notably protons and electrons.
	2015-10-22: Have Gravitational Waves Been Discovered?!? 09:55: ... there are a number of ideas for protecting against this, including magnetic shielding and deploying layers of absorbing or deflecting material ahead ... 10:30: ... the idea is, you have this gigantic physical or magnetic funnel ahead of your craft, which scoops up this interstellar hydrogen ... 09:55: ... there are a number of ideas for protecting against this, including magnetic shielding and deploying layers of absorbing or deflecting material ahead of our ...
	2015-10-15: 5 REAL Possibilities for Interstellar Travel 05:34: Channeled with magnetic fields, these pions provide our thrust.
	2015-10-07: The Speed of Light is NOT About Light 03:03: So an electric skater monkey on a rollerblading pony generates a magnetic field, obviously. 03:27: She sees the monkey moving at only monkey skate speed, and so gets a totally different magnetic field. 03:37: We don't measure magnetic field. 03:45: See, there's a velocity-dependent trade-off between the electric and magnetic fields. 03:03: So an electric skater monkey on a rollerblading pony generates a magnetic field, obviously. 03:27: She sees the monkey moving at only monkey skate speed, and so gets a totally different magnetic field. 03:37: We don't measure magnetic field. 03:45: See, there's a velocity-dependent trade-off between the electric and magnetic fields.
	2015-07-02: Can a Circle Be a Straight Line? 09:18: ... don't think the answer is well understood, but since magnetic pole reversal wouldn't affect Earth's orbit or the tilt, any effects on ...

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