How Magnetism Shapes The Universe

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How far can you follow a compass needle? As far as the north magnetic pole, where the needle starts spinning wildly? Compass needles align with magnetic field lines, and on the precise spot of magnetic north, those field lines are vertical. So just tilt your compass 90 degrees and you can continue your journey - either down to the molten iron dynamo surrounding the Earth’s core, or up. But up to where? The answer - to everywhere - and today, that’s where we’re going to go.
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Hosted by Matt O'Dowd
Written by Matt O'Dowd
Graphics by Leonardo Scholzer, Yago Ballarini, & Pedro Osinski
Directed by Andrew Kornhaber
Assistant Producer: Setare Gholipour
Executive Producers: Eric Brown & Andrew Kornhaber
End Credits Music by J.R.S. Schattenberg: / @jrsschattenberg
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[@stkyriakoulisdr]

I am a computer scientist but I did my masters in an astronomy department. I got to be involved in a project where they would map part of the galactic magnetic field with great precision by measuring the polarization of starlight as it travels through interstellar dust. My task was to implement AI/machine learning methods that could learn to automatically detect stars that were polarized due to other reasons (e.g. having strong magnetic fields, pulsating, spitting out material or being galaxies instead) so that they would be excluded from their results. I don't know how helpful I was in the end. Anyway, this video addresses a lot of stuff that I learned during that year, so I thought I'd share my story.

[@davruck1]

Magnetism is ignored by many astrophysicists which is a huge mistake

[@barefootalien]

Neat! Thanks for sharing! I've often wondered how much and how often machine learning is used in scientific analysis. I've heard of some uses over the years, of course. Obviously, CERN uses it to help prune the less interesting results from the LHC's detectors. And I've heard that some new data analysis techniques using machine learning were in use in astrophysics, but it's cool to know for sure that it's helping!

[@kennarajora6532]

I had no idea machine learning was involved in this stuff. Anyhow, this was very informative, thanks.

[@esecallum]

its banned. and anyone who mentions it is considered a crank. the BBT is like a religion. anything that mentions electric fields or magnetic fields is hearsay. they have even resorted to renaming things. for example giant light years across plasma filaments have be renamed as structures!

[@davruck1]

@@esecallum they even have paid trolls who will harass you on social media if you don’t toe the line. It’s very clear that galaxies are not randomly distributed, yet they can only talk about conveniently distributed dark matter.

[@ivanelrino]

Shoutout to the digital artists. Eye-popping work in this episode. Van Gogh is ok too.

[@MaryAnnNytowl]

"Okay?" Just "okay?" Hmphh... 😤

[@CoryAboud]

Agreed, visuals that good really help

[@Si-Al-Ti]

Ear-popping visuals

[@Billy-xl4sv]

Very true

[@rogerjohnson2562]

Van Gogh is as good now as he was then... not!

[@onebylandtwoifbysearunifby5475]

At astrophysics conferences, if you can't think of a good question: "Have you considered magnetic fields" usually comes up... Because no one understands them.

[@EnglishMike]

@nate0 Or maybe it's simply not possible.

[@ripvanwando]

@nate0 Reminds me of 3 blue 1 brown mapping fluid dynamics of a cross section of air with lasers. The fractal structure of swirls and interference of different flow types - only this is with extra charged particle chaos and it scales like gravity with across different massive bodies. I suppose the fluid dynamics cross section implies space is completely filled at various densities. However, I also suppose I have 0 idea about any of this and fluid style chaos probably doesn't reflect the reality of magnetism even remotely haha.

[@vampyricon7026]

@@ripvanwando Relativistic magnetohydrodynamics (stellar physics for big stars) is just what happens when someone asks "How can we toss as many nonlinear systems together?"

[@danieljensen2626]

@@luddite31 Yeah, pretty much. Too complicated and too many variables to really make useful theories. The other popular question is "What about binaries?" for the same reason. If the system you're observing is actually a binary it pretty much ruins your attempt to explain what is going on.

[@friendlyone2706]

Only proves more astronomers should be talking to radio astronomers for whom -- for over 50 years -- the question has been "Have you considered THIS magnetic field."

[@leovalenzuela8368]

7:01 Van Gogh was like “wait, you guys AREN’T seeing this?”

[@TheActionBastard]

"...you mean it *doesn't* look like this to the rest of you?" *all shake heads slowly*

[@TheMarshmellowLife]

I just got to that point in the video and I came looking for this comment 😮❤️

[@mal2ksc]

I went to a rave held during a meteor shower, and with the assistance of some trendy chemical amusement, the sky looked a whole lot like "Starry Night". So I'm guessing the simple answer is that Van Gogh used psychedelics, or his internal chemistry was messed up enough to do it for him.

[@MaryAnnNytowl]

@@mal2ksc we know that he dealt with mental illness, so I have always thought that whatever chemical imbalance might have caused that illness may very well have caused him to see things much differently than regular folks. And every time I see a mention of his _Starry Night,_ I remember the Doctor Who episode about him... and that episode makes me ugly-cry at the end, every single time.

[@DialecticRed]

@@MaryAnnNytowl Hmm, it's an interesting notion, but I am a bit skeptical about it. I do not know if some people are capable of seeing light in other wavelengths, I've certainly never heard of such a thing, but I would imagine that this is not possible. Still cool to think about.

[@brianmessemer2973]

"Let's hitch a ride on a field line, and see how far it takes us." Great line.

[@CaedmonOS]

I would hope it would be a great line I want it to take me somewhere fun 🤣

[@PeterFerenczy]

Someone get the Rick and Morty staff in here!

[@jugrajbatth62]

Make sure u have ur beer and snacks on u while riding

[@greggorman5537]

It would work for a wormhole

[@tezzeret2000]

Talk about a field trip, am I right? :P

[@Hakasedess]

"[The surface of the sun] is a violent place, magnetically speaking." I can think of very few ways in which the surface of the sun isn't a violent place, really

[@yendorelrae5476]

Dr Manhattan walked the surface of the sun while on vacation!

[@Hakasedess]

@@yendorelrae5476 True, but he's also omnipotent.

[@niks660097]

@@Hakasedess True, but he is also fake and not real, and copyrighted by DC..

[@lancerben4551]

The sun is incredibly stable for the amount of energy potential it contains. That said I believe we greatly underestimate the dangers of solar flares. A strong flare directed straight at us could wreck havoc. The sun is clearly capable of producing strong storms and they are hard to predict.

[@milferdjones2573]

Considering all of man's atomic bombs all detonated at once is insignificant to a second of solar activity violent not close to describing it.

[@isaacnarrett3085]

I’ve been watching this channel for years, even before I was a fan of science or anything. Then as I watched and started my university degree, I became more fascinated and decided to study physics. This channel always gave great explanations and intros to topics I was learning in class, so I was always happy to share videos with friends. Now, I will be starting graduate school working on planetary magnetism, so it feels full circle seeing a video on my topic. Thanks for all you do, for all of us who are curious about the inner workings of 🤷🏻‍♂️ spacetime 🤷🏻‍♂️

[@OutsideTheBoxEngineering]

That’s cool

[@liquerinfrnt]

That footage of the CME was one of the most beautiful things I've ever seen. So much power, to just blast off more mass than the entire earth like that

[@tomkerruish2982]

It's not more than Earth's mass; it's "only" about a billion tons. It is, however, larger in size than Earth.

[@mozkitolife5437]

Matt continually impresses me. These recent episodes have been out of this world. The graphics and productions from references are astounding. To possess an understanding of the heliopause and beyond makes me feel very privileged indeed. I wish everyone on Earth experienced this level of knowledge.

[@dustman96]

Perhaps the most awesome part of the astronomy community is how they come up with ingenious workarounds to solve problems.

[@ikkeheltvanlig]

the sentence "the aligned electron spins in a ferromagnet" taught me more in one second than several "how do magnets work" videos have. thank you.

[@wayfarerzen3393]

Finally. FINALLY this is being covered. I've always thought of the magnetic field lines and other magnetic properties of the solar system as forming, vaguely speaking, some sort of circuit, where field lines of the sun significantly affect that of its planets. Also wondered if this relationship has any inductive properties. Also, with the galactic magnetic fields, I read somewhere that they may be shaped like a torus or double-torus, lines travelling far outside the galaxy eventually wrapping back around to the core. I haven't seen the science on that but it would make a lot of sense if it was true.

[@kreechrr]

So what I'm getting is that Magneto is secretly the strongest Marvel character. He could alter being's perception of reality by changing the very polarity of light seen.

[@metalcake2288]

Modulation would be more effective. High skill ceiling with this ability

[@crackedemerald4930]

He would also have the power to send lightning because magnetism is only one side of electromagnetism

[@soulblade9142]

except most humans can't detect polarity of light so.... not that you needed debunking but.... unless he can reach into the sun and conjure up a solar storm, i'd say Magneto aint that OP imo

[@soulblade9142]

i'm also drunk in case that was just complete nothingburger

[@kreechrr]

@@soulblade9142 sure but with the right writer he could just meditate and start to feel the miniscule fields around individual particles and exercise his influence on them. Or something. Maybe he's given cosmic abilities for a single story and there's a lingering amplification.

[@benmcreynolds8581]

I just had to take a moment and realize how amazing it is that when I was born, black holes were theoretically proven but now we have ACTUAL visual evidence and proof of black holes. That's absolutely amazing!

[@brianmessemer2973]

Matt, you just perfectly explained polarized light in the most nonchalant way. 🤯👍

[@Novastar.SaberCombat]

IKR?! Actually, I thought the entire thing was bloody perfect.

[@szamszatan]

exactly my thought...! i watched an entire episode on this n a 'rival' channel, but should have just watched this

[@goldenwarrior1186]

@@szamszatan out of curiosity, what channel are you talking about

[@szamszatan]

@@goldenwarrior1186 kzbin.info/www/bejne/borOl3icqZmjY9k Eugene Khutoryansky

[@ShubhamShubhra]

Great to see Faraday’s name appear in Cosmology long after he is gone, showing just how remarkable his contribution to physics is. Long Live Faraday.

[@CamEron-nj5qy]

"Astronomers are also tricky and so have tricks" 😂

[@Invalid571]

Not the finest moment of PBS spacetime. 😅

[@GreasyBirb]

silly astronomers, tricks are for kids.

[@MuscarV2]

"austromers" what?

[@IHateUniqueUsernames]

@@Invalid571 Au contraire, it made me breathe a little harder. A nice play on using the work as, I believe, a verb, adverb, and noun.

[@holden_tld]

you can tell by the way they are

[@MrDbrennen]

Posted 24 seconds ago, just the way I like it

[@Ph0_Q]

3 minutes ago not bad

[@Nillowo]

15 minutes. Still decent

[@realzachfluke1]

Ahhh, posted _26,316,641 seconds ago,_ just the way I like it 😏🫴 (assuming the video was uploaded at noon that day lol)

[@LifeofBlog]

Seeing your comment a year later... lol

[@gorenewable]

This is still the most relevant comment

[@thomasgoodwin2648]

As we seem to keep finding larger and larger physical structures in the universe one has to wonder what the magnetic field of the entire universe itself is like, and how it affects it's overall internal structure.

[@esecallum]

It is a taboo subject

[@thomasgoodwin2648]

@@esecallum There are no taboo thoughts, only taboo deeds.

[@xarmanhsh2981]

he is talking about the magnetic universe conspiracy @@thomasgoodwin2648

[@CSpottsGaming]

11:59 I believe you meant the M87 supermassive black hole, M81 is in a different galaxy altogether!

[@Xeridanus]

M81 isn't IN a different galaxy, it IS a different galaxy. The Messier series (M##) are all galaxies iirc.

[@CSpottsGaming]

@@Xeridanus I was referring to the black hole specifically, as was Matt.

[@justineelzak4285]

@@Xeridanus messier objects are various things from supernova remnants to galaxies.

[@halweilbrenner9926]

81 87 all the same me

[@Xeridanus]

@@CSpottsGaming M81 supermassive blackhole is in M81, saying M81 is in another galaxy is technically incorrect as a galaxy can't be inside itself. Just saying 'The M81 blackhole" would be enough clarification.

[@jflannery11JohnnyTru]

This might be my favorite episode. Bravo. Never knew magnetism was so cool.

[@itmaybeokay]

Magnets: How do they work? According to seminal work by Insane, Posse, Et. Al - the answer is "miracles".

[@revenevan11]

😆 love that citation!

[@MGmirkin]

To anyone else, who knows what they're talking about, magnetic fields are driven by electric currents, either bound electrons in orbit around atomic nuclei, in the case of permanent magnets, or at the scale of the electrical circuit in macroscopic objects / processes. Pretty much physics 101 level stuff.

[@itmaybeokay]

@@MGmirkin in the case of permanent magnets it has to do with the spin of electrons, not their orbits. There are videos about it in this channel. It’s discussed briefly in this video. That said, the fundamental forces of nature existing at all, let alone existing in such a way to create all this “stuff” in the universe, rather than just an ever expanding cloud of dust after the Big Bang - some might argue it’s fair to call that “miraculous”. Perhaps the juggalos were on to something with that song… No. No they were not.

[@faaip0de0oaid]

the seriousness when he said that was hilarious

[@cmacmenow]

As always, these deep dives and beautifully constructed talks take my mind and imagination to another level! Since a child,magnets and magnetism have always intrigued and mystified. Now, even more so.Totally brilliant and deeply magnetic!

[@steelmagnum]

The scales and structures that can be found in our universe really are absolutely mind-boggling. Really brings to mind Einstein's posit of universal bigness and universal smallness. The same structures repeating just at different size and time scales

[@unvergebeneid]

The field line pointing straight up from the north pole would make the compass point _south_ in that direction though, not north. So if you followed the needle all the way to the magnetic north pole, at that point down you go, not up.

[@szopad7832]

I don't know why am I so addicted to this, but for the past two days I hit the refresh button way too many times. Finally it happened, on the 3rd day, at 22:25, the last refresh before going to sleep. Thanks :)

[@sandybarnes887]

I suppose you could start watching the back catalog

[@cdvamp]

the animations and graphics were on a different level this episode. kudos to the editing team

[@UnionYes1021]

Thank you again for another well thought out episode! Miss seeing you in a shirt. You are a good teacher. Thank you for sharing your skill and work.

[@cheknauss9867]

Well this channel is just simply the best on KZbin, obviously.

[@garypalmer997]

Who would've known the universe had such a magnetic personality

[@Desirion83]

Gary you the + to my -! Sorry I ended up dating Gravity instead, less complicated....

[@SplendidFellow]

This is the best most educational and fascinating show that has ever been released on anything by PBS

[@franciscoturri3717]

Im a physics student at the Cordoba University in Argentina, every time i watch one of yours videos i remember why im studying physics. Thank you for all your content, keep up the good work!

[@frankdaze2353]

So many amazing new visuals. You lot never fail to deliver on the quality ⭐️⭐️⭐️⭐️⭐️

[@The_Tauri]

This is the best channel in my spacetime.

[@mal9369]

Man, that magnetic field of the galaxy is incredible. It's almost like an ecosystem. The stars are formed, consume matter, then die and eject their guts, which are then picked up by the galactic magnetic field and funneled back into the center to fuel more start formation. Maybe that's why we see so many galaxies with super massive blackholes at their center. They didnt run around gobbling up stars but rather formed through the same process of start formation where the growing galactic magnetic field funnels particles into the center more and more, creating the black hole at the center from the wash of matter.

[@EddyA1337]

Thanks for keeping this content going Stephen. Sounds like you were very generous.

[@jordanvermeer4567]

Amazing reference to *bleeping* magnets, how do they work. Thank you.

[@petertriller8343]

Question: If I run into a wall, the force that stops me is ultimately electromagnetic, right ?

[@TysonJensen]

Actually it’s the Pauli exclusion principle, your electrons can’t occupy the same space as the wall. Not to say that the EM forces aren’t important, how your tissues jiggle as a result of the collision is a result of these forces. These forces also determine at what momentum the wall will decide to break.

[@davidhand9721]

@@TysonJensen I've heard this before but I can't buy it. The Pauli exclusion principle isn't a continuous force and therefore does not lead to a potential that can reflect particles. When things collide, they don't get anywhere near as close as atoms in a white dwarf; there's no moment at which the pressures are comparable, and since it doesn't result in a potential, there should be no effect until the particles are nearly right on top of each other. The electrostatic force, though, _does_ create a potential everywhere and it does hit infinity at the position of a charged particle, which means that any amount of momentum can be reversed for an incoming particle _before_ it gets that close. I mean, the exclusion principle only works if particles are less than a Planck length apart _and_ they have the same momentum; how can two particles with the exact same momentum even collide? They would be at rest relative to each other. It doesn't make sense for those conditions to be met at room conditions. Please explain how the principle can affect particle momentum without relying on electrostatic potential outside of a white dwarf or neutron star!

[@TysonJensen]

@@davidhand9721 The exclusion principle works over the entirety of the orbital, it extends many, many orders of magnitude farther than the Planck length, I don’t know who told you that it has anything to do with the Planck length. The exclusion principle and electron quantization are really the same thing. Two electrons, being fermions, cannot share the same quantum numbers. The electrons feel no force, they simply cannot coexist with the same quantum numbers. The forces happen over larger distances, the electrons at the contact surface are hard stopped by their inability to interpenetrate each other, and the molecules stacking up behind adjust accordingly.

[@furqanshariff]

@@TysonJensen It is said that bosons do not obey exclusion principle, so they should perfectly go through one another but in many laser experiments light seems to bounce or refract a bit due to collision, why

[@TysonJensen]

@@furqanshariff I am not sure. But fermions can pop into existence, then disappear due to the uncertainty principle interacting with the vacuum. I would anticipate that bosons interacting with bosons would have something to do with the local energy level making it easier for fermions to pop up. A pure boson-boson interaction should not permanently change either boson, but purity is not something our Universe appears to value.

[@Haplo-san]

Thank you for amazing episode with the beautiful visuals.

[@mouseDown83]

Another great production! Thank you for making this.

[@12jalbrandao]

I've been waiting my entire life to hear this!

[@EnglishMike]

Phil Collins? Is that you? Something in the air...

[@12jalbrandao]

@@EnglishMike Yeah! But can you feel it?

[@chance_in_the_chat]

"Magnets how the f××× do they work?" Did i just hear Matt quote a line from an ICP song?? I think I've switched timelines again :-X

[@hhaavvvvii]

It's pretty common for physicists to quote that line.

[@danieljensen2626]

I think every physicist knows that line just because it's funny, even though most of us have ever heard the song or actually know where it's from.

[@Ni999]

Recent studies show that the seed electrons for the Earth's geodynamo comes from electron scattering resulting from convection cycles in the molten core. Planetary spin provides the momentum to maintain the dynamo configuration but not enough to seed it. I was immediately reminded of the hot electron model common to electronics.

[@timvb2]

Now you seem to be getting to understand the nature of magnetism..Well done great video !!!

[@daytonduck]

I loved the Van Gogh inspired imagery at about 3:35!

[@benhammett1189]

Great episode ! After watching the episode I wonder how much distant galaxies effect each other in their movement through their magnetic fields and wether these could slow down them drifting away from each other since there wouldn't be any field lines pointing from one galaxy into absolute nothingness.

[@soulblade9142]

obviously not that much since they apparently are drifting away from each other into complete nothingburger

[@jaybingham3711]

It won't be too surprising that we will later determine magnetic fields play a role in our new observation of cosmic filament rotation/spin: www.sciencenews.org/article/dark-matter-cosmic-filaments-biggest-spinning-objects-space

[@livedadyt10]

Well explained. The graphics were phenomenal. Thanks.

[@shawnmckernan2277]

Yay! Finally some coverage about the magnetic influences and interconnectedness of cosmic bodies. We're starting the 6000 year galactic field wave events here in the solar system. The sun's going to get very active and there could even be a micronova. The earths geomagnetic excursion is happening. The field is weakening and the North pole is moving fast. Some of the weather events we are seeing are due to this (new type of lightning identified in the mountains for instance. The earthquakes happening globally are due to these changes. Love this show. ALWAYS learn so much.

[@elishmuel1976]

I can't thank enough the PBS Space Time team for creating this amazing content for all these years! From the bottom of a scientist's heart, you make the world sane and logical again. 1:39 Is it the Left or Right hand rule? I'm fairly certain you'll cover that aspect in the video :)

[@gx_no]

I love how Matt travels to space every time to teach us.

[@CC-iq2pe]

I am totally amazed by your deep explanations about galactic physics

[@olejakobaune8033]

This is the best and most thought inducing video ive seen in a long time.

[@only1kingz]

I still have trouble making the connection between WHY moving charges create a magnetic field. Like, I just don't understand the mechanism besides just the observation that it does in fact happen.

[@dumbasgenius7227]

Yeah me too. I have never found anything on it.

[@NovaWarrior77]

Special relativity bro. kzbin.info/www/bejne/f5qao5p_hsaqodE kzbin.info/www/bejne/Z4WuhJl3oLyKhJI

[@abidanjam1234]

kzbin.info/www/bejne/Z4WuhJl3oLyKhJI I think this video might help you , I have also suffered from the same question

[@lornelee1891]

@@drdca8263 the only issue I see with this is thinking about how a capacitor doesn't create flux lines

[@tomkerruish2982]

It's special relativity. Suppose you have two charges at rest with respect to each other and you. You'll see them exert an electrostatic force on each other with accompanying accelerations. Now transform to a frame in which they're in motion perpendicular to their separation. You'll see the same charges and separation, but the accelerations will be reduced due to time dilation. This change is attributed to the presence of magnetic fields. This is why magnetic fields are only generated by moving charges and only affect moving charges. (Okay, electrons aren't really spinning yet they have a magnetic dipole moment, but that's all quantum and therefore magic.😁)

[@brandonmunshaw2854]

Magnetic fields are continuous right? Are magnetic field lines just a way to visualise the shape and strength of a magnetic field, like isotherms on a weather map?

[@tomkerruish2982]

Yes.

[@brandonmunshaw2854]

Awesome! Related question: when magnetic filings trace magnetic field lines on paper, why do they clump together to form lines?

[@tomkerruish2982]

@@brandonmunshaw2854 At a guess, I'd say that the filings themselves become (slightly) magnetized and so clump to each other. Field lines are a mental picture to help visualize the invisible, like the rubber-sheet picture of curved space for general relativity.

[@brandonmunshaw2854]

Yeah, now that you mention it, the filings are usually tubular, so it makes a lot of sense that they would want to align end to end as best they can against friction, making lines appear

[@massimookissed1023]

@@brandonmunshaw2854 , yeah, the filings become slightly magnetized themselves, so they line up end-to-end but not side-by-side, so the lines of filings keep some distance between each other. Similar to static electricity making your hair stand up. The hairs are aligning to the field gradient, but also repelling each other, because they are similarly charged.

[@BackassWordsWeirdworld]

I'm really glad you are on the job. I think you have an excellent understanding of our ever changing "current" reality situation. Keep them wheels turning. You got this. Thank you. God bless.

[@anthonygonzalez2897]

Something so satisfying about the moment when he drops the final, signatory "Spacetime". Like Ron Burgundy, my man has his signature. And it is no less than Spacetime itself.

[@sjzara]

When I was a youngster learning about electricity and magnetism I was intrigued by what magnetic field lines were. What were they made of? It was a surprise to discover that they didn't exist. Fields lines are only used to illustrate a combination of the direction of the magnetic field and its strength. Perhaps the use of the term "magnetic field lines" should be reduced to avoid confusion?

[@Novastar.SaberCombat]

It's as good point as any other regarding semantics and labels. Relevant to the concept, naming 'Depression' with a capital 'D' did NOT help the world understand it very well ('Anxiety' as well--dumb label for the concern). But anyhow, perhaps 'gravitational web waves'? 😁

[@annoloki]

It's not just field lines, the 'field' itself is a mathematical term, used to express variance in predicted behaviour between two or more interacting "things" through the use of field equations... see, it's not about what the universe IS, it's about what the universe DOES, the whole of physics is a model. Take the standard model of particle physics, for example... so important was it that you don't take this description as a literal description of what the universe is, that they put it as the second word, right up there in the title... it's the standard MODEL. An electron is a set of behaviours, that follow a pattern, that we can recognise, and call other instances where we see the same behaviours "an electron". Particle or wave? "She's a sister, a mother, a wife and a friend", well which one is she? None! Those are names of relationships, ways of behaving when interacting with others... we simply can't talk about these things in a way that doesn't involve interactions, because without interacting with something, we don't even know it's there, let alone what it is. So basically, all of physics is a way of mapping the ratios between measurable behaviours in interactions. But yeah, it does seem like this bit of information is much harder to come across for how fundamental it is.

[@DataumCats]

Magnetic field lines absolutely exist, except in the most trite and pedantic sense. The magnetic field is a velocity field, and at any point in the magnetic field there is a well defined stream line you can follow. The fact we're limited to visualizations that describe a continuous phenomenon using a discrete approximation doesn't make the concept invalid, and to say it should be avoided means we should be avoiding all imperfect visualizations. Which is to say we should avoid essentially all visualizations.

[@sjzara]

@@DataumCats I’m definitely pedantic - it’s fuelled my approach to science since childhood. Magnetic field lines are an abstraction. You can’t see them, and they have no effect on reality. They are the equivalent of the curving rubber sheet used to illustrate curvature of space. There is no sheet, and there is no rubber.

[@UteChewb]

Coincidentally, yesterday I heard, via Anton Petrov, of a paper that argues that the size / density of the cores of the inner planets is a consequence of the strong magnetic field of the young solar system acting on ferrous particles in the accretion disk.

[@Novastar.SaberCombat]

I saw this one as well! Someone needs to help get Matt & Anton involved in a collaboration video, hehehehe! 🐲✨🐲✨🐲✨ Thumbs up if you agree! 💪😎🤟

[@EnglishMike]

@@Novastar.SaberCombat Disagree. Anton does sterling work, but he's not a professional scientist and doesn't really have the necessary depth of knowledge or relevant experience to do any meaningful collaboration with Matt. (That's not a knock on Anton. He'd probably agree with me.) Now, a collaboration with a scientist like Sean Carroll or Becky Smethurst would definitely be worth seeing.

[@MaryAnnNytowl]

@@EnglishMike there are several other KZbinrs that Anton would pair well with, but I think you're correct. He does break down new scientific papers into concepts that the layman can understand, but even though was a teacher, before becoming a KZbinr, I think he would also agree that he would be in a bit over his head here. Though I really would love to see him collaborate with some of the other science-based KZbinrs! Maybe ResearchFlatMoon, FTFE, Mr. Sensible, or Sciman Dan?

[@Novastar.SaberCombat]

@@hyperduality2838 On and off. One and zero. Heat/energy and the lack thereof ('cold'). Light and Darkness. 🐲✨🐲✨🐲✨

[@matthewdaw6485]

I don't think you have to be at all remotely interested in the science behind what Matt is saying to enjoy this. Watching this is honestly one of the best visual experiences I've had in a KZbin video.

[@alwaysdisputin9930]

i liked the field lines

[@KutWrite]

Nicely done. I appreciate your humo(u)r such as the Aurora Alert given when Mr. Wilcox travels. This information will be useful for the drive mechanism my characters will use in my in-progress science fiction novel.

[@thomashenderson3901]

When a magnet is pushing away from another magnet, this seeming invisible force is actually carried by what? Is that electrons pushing, or photons or what?

[@DarkMage2k]

Exchange of virtual photons as magnetism is basically electrical force with relativity. Might be wrong. My intuition is this though

[@Samu2010lolcats]

It's carried by the magnetic field itself.

[@ThatCrazyKid0007]

Exhange of momentum between the particles carried via virtual particles.

[@fnamelname9077]

The magic of the druids!

[@JustinLe]

it's really the same force that pushed your fingers away from a table when you push down on it. the same force that keeps a book on a desk so it doesn't fall through. this doesn't quite answer your question, but hopefully it makes magnetism seem a little less mysterious. it's that same force you experience intuitively every day, just over a slightly larger distance than you are used to seeing.

[@Odin029]

What I learned from this video is that astrophysicists are tricky and therefore have tricks

[@dritemolawzbks8574]

As long as they're not turning tricks, they won't have to hire a pimp or madam.

[@ScienceDiscussed]

Great video. So much information in such a short time.

[@acepierceson4430]

I'm impressed by how calm he remains while talking about such exciting stuff.

[@aclearlight]

Incredible show, thank you! The quality of your work and the level of the posted comments and questions all lead me to think of your channel as one of the very most luminous parts of the cyberverse!

[@dakrontu]

Do magnetic fields have any measurable effect on the orbits of stars around the galaxy?

[@halweilbrenner9926]

Who knows? Still working on it.Lots of interaction amongst Fields & different particles & mysterious cosmic forces.

[@friendlyone2706]

Yes

[@The.See3]

Yea

[@guytheincognito4186]

Most likely not since the stars magnetic field is stronger than the magnetic fields around it. It would be a negligible effect if any at all, unless something with a powerful field exists nearby. So it's likely that the stars magnetic field affects the flow of the weaker fields around it.

[@3zdayz]

on 'How An Extreme New Star Could Change All Cosmology' he responds... but massively underesitmates the magnetic field present - yes it does, stars have high iron content, which 1) induces a magnetic field in them (not their own dynamo) and 2) causes them to be attracted; it's the same amount of force as so-called dark matter would provide (only then it's not darkmatter, but magnetism)

[@stephanieparker1250]

A topic I rarely heard about, thank you Matt! 🥰🙌🙌🙌🙌

[@fraktaalimuoto]

Nice video in the subject! I am an astrophysicist who is an expert in cosmic magnetism, and the content looks solid to me. First time I see a presentation of a galactic dynamo in KZbin!

[@roelwijgers]

Great episode! Has there been some study already comparing the missing mass in the spiral arms against these wide scale electromagnetic effects? Since that is a crucial piece of evidence for dark matter

[@eskuriad]

That would debunk Einstein and force astrophysicist to start accepting the electric universe might not be quackery.

[@dritemolawzbks8574]

It's kind of hard telling if this is a genuine question or not, but why are you calling it missing mass isn't of dark matter?

[@giovanniguarino9152]

Finally, a video in which the importance of the magnetic fields (and then, electricity that creates it) is expressed in some way, even if it's still too much underrated by astrophysicists because of their ignorance in the matter. Magnetic fields in the plasma can explain many of the problems that the new observations put to the fans of the universe dominated only by the gravity. My compliments for the job.

[@brettsutherland8390]

Absolutely amazing, thank you!

[@jogandsp]

Thanks so much for making this video! I had no idea!

[@Pratanjali64]

Wait, I thought we were getting Many Worlds Part 2? Edit: just got to the Q&A. I still hope he does the full episode.

[@TheGokki]

This episode was likely in production during that time, Part 2 is probably already done or very close to it.

[@tomkerruish2982]

We did, in my universe.

[@duetwithme766]

Would you do an episode on Earth's Aurorae?

[@bizzehdee]

When trying to explain infinate worlds, the best way i have ever heard it explained is "just because there are infinate possibilities, it doesnt mean that all possibilities can happen... there are an infinate amount of numbers between 1 and 2, but none of them are '3'"

[@ahamzah12]

I love this episode. My favorite one so far!

[@dreammfyre]

Me before this video: Magnets how do they work? Me after this video: Magnets how do they work?

[@sahelanthropusbrensis]

*Oh boy, grabbing my popcorn and waiting for the "eLEctRic unIVersE" lunatics.*

[@JRichardson711]

Why are they lunatics? They said electromagnetism has effects on larger scales of the universe that were previously overlooked. Seems like Matt just confirmed they were right.

[@pronounjow]

Well, one thing they haven't been able to provide a meaningful explanation for is gravity. The "electric gravity" proposal from the chief advisor for EU is total bonkers (you have to see it to truly believe me), and the same dude thinks Earth is hollow due to Earth primarily consisting of positive charge IIRC, but that seems to contradict his "electric gravity" proposal. *groans*

[@byrnemeister2008]

@@JRichardson711 Because they think stars are powered by electricity generated at the center of the galaxy. That stars are little more than light bulbs powered by invisible electric currents that must be millions of amps that somehow conduct through the vacuum. Yep they are bonkers.

[@drewmandan]

Attack the argument, not the person. Otherwise you risk throwing out interesting insights by making the category error of lumping them in with the nonsense.

[@NuclearCraftMod]

@@JRichardson711 The electric universe proposes complete nonsense such as electromagnetic "polar gravity", that relativity is mathematically flawed and other complete tosh.

[@lukainteressado.3202]

this video is so beautiful I've watched it 5 times and counting

[@AnRodz]

This is one of the most interesting episodes I've seen. It took me 2.5 years to get here, but here I am at last : )

[@geraldw.8118]

Sometimes I get completely drunk and watch these and learn nothing so I don't feel like I'm wasting my time

[@jaredhamon3411]

Thank goodness for Differential equations.

[@day3455]

Wow! I simply loved this episode of space time!

[@johncao6516]

I learned "circular polarization" in molecular biology/biochemistry. Never thought of it in other fields but I guess it make sense to hear it in a astrophysics context.

[@DrZedDrZedDrZed]

Sugars be wild like that...

[@qzbnyv]

This video is going to be perfect bait for those crazies. You know the ones I’m talking about. Scroll down far enough on any astrophysics video and you’l find them commenting.

[@KnightspaceORG]

Just wait for videos about how PBS agrees with EU. I can bet at least two will show up in a week.

[@DaedalusR]

>he’s watching a video about near-invisible supercharged tornados being shot out of a incomprehensibly large space fireball but thinks human conspiracies are fiction makes sense lol

[@gabrielgarcia7554]

@Daedalus That’s because we have evidence that is independently verified versus assertions made by people with circumstantial evidence (if at all) riddled with logical fallacies. Also, we’re willing to change our minds in light of new evidence, whereas most conspiracy theorists just move the goal posts primarily because the logic in which they use assumes the conclusion as their first premise and they cherry pick evidence that supports this conclusion.

[@damonedwards1544]

The "Electric Universe" people. Yeah, I thought the same thing.

[@SuperSmashDolls]

Same as how doctors that talk about coronavirus have comment sections full of vaccine, mask, and disease denialists?

[@elaadt]

Is there any correlation between a galaxy's magnetic field and the amount of dark matter calculated to be in it (from star motion observations)?

[@GeraldM_inNC]

Dark matter doesn't exist. Electrical currents are what holds the galaxies together. The so-called filaments of dark matter are electrical cables.

[@aronworlen1752]

@@GeraldM_inNC bs

[@GeraldM_inNC]

@@aronworlen1752 There is no evidence whatsoever for the existence of dark matter. It's just a wild card invented to account for the fact that the equations based on gravity alone don't work.

[@aronworlen1752]

@@GeraldM_inNC Ghost galaxys

[@frede1905]

Interesting question. I hope that is researched, or will be.

[@JCO2002]

Particularly good episode. Thanks.

[@MrEzystreet]

Very good explanation and visuals. Very complicated subject. 👍

[@zfnQRZJT]

0:00 This is the sort of thing you get when astronomers try to become navigators

[@ulysisxtr]

Matt said "Astrophysicists" but I heard "gastrophysicists".... I think I'm hungry...

[@Theraot]

​@Todd Starbuck Is that the book of all the ancient gods exiled by the giant spaghetti monster?

[@MaryAnnNytowl]

@@Theraot shhhh... we don't speak of these things among nonbelievers.

[@KWifler]

Astronomy or gastronomy? One small letter could change your life forever.

[@troyjacobs8530]

Breathtaking, and rife with the kind of truths monks talk about behind closed doors lol. I like the model of riding a field line a lot, and what you said about Van Gogh. The painting he did of the wheat field with three paths to nowhere before he died is another instance of his magnetoreception. Ask a hospice patient if they see the same thing next time you spend time with one.

[@luisdmarinborgos9497]

Thank you for making this quality content accesible to everyone

[@Tzitzemine]

In the "Many Worlds Theory" where does the energy come from to create every split world with?

[@ayushsharma8804]

I think conservation of energy only applies inside a universe, so it comes out of no where. I don't know how you will apply Noether's theorem in many worlds.

[@boringturtle]

My understanding of it (which could be totally wrong) is that there isn't so much another physical world as a set of particles out of phase with each other.

[@NoConsequenc3]

Why do you assume it takes energy

[@TysonJensen]

There’s an implied gauge invariance. If a particular “World” has a particular energy density, then it splits such that each daughter has half of that density, neither of them notice anything different. That’s because the probability density function is presumed to be relative. This only works if the Schrodinger wave equation is never itself quantized. If it is quantized, then what happens is there’s a fixed number of “Worlds” each with a reasonable fraction of the density function, with the least probable worlds winking out of existence entirely. That last is the only Many Worlds theory that I consider probable - if there is a fixed count of realities but that fixed count is stupendously large, we’d never know, but we could rule out worlds where leprechauns rain out of the sky as being too improbable to be included.

[@viliml2763]

Splitting worlds doesn't use energy

[@blurrrrrr44]

At last, a video that explains the hypothesis's i had as a kid & wondered how magnets worked, and if the sun & even galaxies had a common magnetic field. I was right.

[@magnushorus5670]

These are the best videos on all of KZbin

[@mattman8685]

Fantastic work! You've made the nerd in me very happy! Thanks!

[@arkadryan7484]

My new favorite words ... "Quantum Wiggles".

[@robertbrown5887]

who is the quantum wiggle and what colour are they??

[@timtaler2435]

I thought that dipol fields don't play a role on large scales as the decay with 1/r³?

[@tomkerruish2982]

My thoughts too.

[@frede1905]

My bet is that these fields that he is talking about are typically really small, especially the interstellar ones. But yes, I do wonder how they can be strong enough to have any effect at all.

[@ThatCrazyKid0007]

It seems the fields are boosted from the interactions with other fields allowing them to add up and extend their influence much farther than the initial dipole can. At least from what I could take way from this video.

[@NuclearCraftMod]

Dipoles have an inverse cube law, but the magnetic fields generated by currents can be more like 1/r.

[@jmk1727]

14:18 -- was that a nod to "What The Bleep Do We Know?" that blew me away when I first saw that.

[@rogersledz6793]

Thank you so much for uploading this video. It is helping me get through the pandemic!