This is fantastic I'm so glad you pointed it out

too bad anions aren't called dogions

WHY DID HE NOT TELL US HIS GLORIOUS PUN????

Because everyone has already heard it before. Or at least, anyone with a half-way decent high school chemistry teacher . . . .

Or because they aren't living in an English-speaking world

+Martin Verrisin lol so true

+Martin Verrisin it is now

+Martin Verrisin XD XD i think you just made it a quote

xD

What about when someone tells me "You are looking fat"? What should I say?

Agree fully.

This is why magnets blow my emf reader off the charts!!!

Unfortunately the video is wrong. As is shown In "Is magnetic field due to an electric current a relativistic effect?" by Oleg D Jefimenko available to download on Internet, if one assumes that the interaction between moving electric charges is entirely due to the magnetic field, then the same relativistic force transformation equations make it imperative that a second f ield-this time the electric field-is also present. Therefore, since it is impossible to interpret both the electric and the magnetic field as relativistic effects, one must conclude that neither field is a relativistic effect. It is a very spread missconception. Several authors have asserted that the magnetic f ield due to an electric current is a relativistic effect. This assertion is based on the fact that if one assumes that the interaction between electric charges is entirely due to the electric field, then the relativistic force transformation equations make it imperative that a second field-the magnetic field-is present when the charges are moving

​@@drslump9314 I just read through that paper. Not being a mathematician, I doubt my ability to explain the concept clearly to anybody. (The acid test for understanding a thing). However.., if pressed.., at 1:30 in the video, the fact that the electrons are moving ought to invoke the same relative principle. But it doesn't. You can't have it both ways. -That is, you can't have a relativistic effect only when the cat is moving, but not when the electrons are moving. Which means the theory doesn't work.

@@MarkOakleyComics it is an interesting reading. it shows that what he said in 2:44 is completely wrong. Neither field is a relativistic effect. Some animations are missleseading. I.e. Electrons drift velocity is slower than a tortoise. Some topics are not even mentioned as the role of surface charges

someone like me.

its true though magnetic field is just electric field in a diff. frame of reference, and solves a lot of issues with force fields in general in 19th century, Lorentz found that before Einstein...

This is a very good educational video, but it is just a special case. For example, a single charge also produces a magnetic field. That can not be explained by applying relativity in this fashion. Advanced maths and Lorentz transformations come in there.

@@_BerKill_ someone like me as well

me too i haven't got any answers until i watched this 😮 8 years wow this is amazing

It represent cat-ions

Even scientist are obsessed with pussies

He was making fun of the stupid people who used re-equalization to basically screw up quantum theory, which they did and hence why it makes no sense now.

So hows your single life going now

Trust me, after 20 years in wifey prison, single life feels friggin' awesome! xD

@ki kus Is that supposed to be sarcasm or what? What led you to believe i got offended, I implied that his wife got offended and divorced him. Sorry Im confus

@ki kus idiot

Destro Metro I didn’t understand your joke can you please explain it again ASAP??

But it is not... "Is magnetic field due to an electric current a relativistic effect?" by Oleg D Jefimenko available to download. It shows it is impossible to interpret both the electric and the magnetic field as relativistic effects.

I'll admit I'm also convinced that it's not true. When you do a simple thought experiment of imagining only moving electrons inside the wire (no protons or neutrons) and then an outside electron, one case where the outside electron isn't moving, and then another case where the outside electron is moving in the same direction and speed as the electrons inside the wire. When we do this thought experiment, classic electromagnetism contradicts what you would predict happening when comparing it to the theory where the magnetic force is only a result of the electric force combined with relativity.

What happened to electric field and magnetic field are perpendicular to each other and interchange their energy in electromagnetic wave??

@@drslump9314 You got wrong what bit though. There is no real world difference between magnetic fields and electric fields, they are one and the same. We use these terms because they make "more sense" in a Newtonian worldview. But the universe is not Newtonian.

@@drslump9314 jefimenkos eq are illuminatin, but a current is just a charge viewed from a moving frame

Hey buddy.. I too teach physics in India would love to learn from your experience. If I can get any of ur contact

Would be very grateful if you teach whatever you learn to your students as well😊 Marks are not everything These amazing concepts will make physics both easy and fascinating for them

I know you meant it well, but tbh that's a bit sad (nothing against you!!). How aren't physics teachers required to know this, what kind of joke is uni degree for a highschool (that means right until university right?) teacher to not know this.. So confusing how bad "our" education is before uni and then you go to uni and everything is over 9000 and all profs are angry because you didn't learn it in highschool.. wtf:D

@@ibonitog , if understanding relativity were required then there wouldn't be any high school physics teachers!

@@HR-yd5ib yeah and that is sad.. in my high school, special relativity e.g. was part of the final year curriculum.

Ur lucky to have a professor lime him.

According to Schrodinger it will be both on the exam and not on the exam.

And the answer is - Doesn't matter!

@@SumNutOnU2b I literally just watched a video on Schrodinger lol.

@Max....you saw @Donks comment and watched that video for the sole purpose of leaving that comment. Also does this have anything to do with the confounding fact that some people are rubber and some people are glue?? Unfortunately I’m glue and I’d like to change that if possible.

The length contraction happened in 1D but density is 3D. This is a contraction without necessarily density increase. The density should be determined such that the total charge is zero relative to positive particles reference frame, happens to be the same as the observer or anything "at rest".

Alex Yang please explain it more deeply. I didn't get what you said about 1D and 3D density

Emergy Man you are absolutely right. There is a flaw in this videos explanation.

Electromagnets might offer a simpler case for illustration. In the loops of wire of an electromagnet, the current is flowing so the electrons in each successive loop are all in the same frame of reference and so are the (to us) stationary nuclei. But to the electrons the nuclei are moving and seem slightly closer together(making the next wire-loop over seem positively charged) and to the nuclei the electrons seem a bit closer together (making the next wire-loop seem negatively charged), so the loops all attract one another, because there is a slight curvature of the spacetime-like manifold that constitutes the force applied by the electric field.

Ya ur right but only if the wire is thick enough to carry so many free electrons and even if it is thick charge wouldn't interact as due to resistance in wire the current decreases

This is a very clear view of why the stationary electron stills sees the cable as neutral, while the moving electron does not. Thanks for sharing,

Omg thanks. I thought it was infuriating no one noticed that this was not explained by the video

This should be the top comment. This was my biggest question coming out of the video.

i also think the fact that the positive ions are contracted plus the egative ones spread out means that the forces stack up wich is why it's negligable from the lab point of reference

I have been struggling with this for long and this explanation seems to solve it very clearly. Thanks.

The contraction is not comparable to compression of air for example

I agree and I think the wire should have electric field from rest frame like the way you mentioned, which cause the magnetic needle to deflects

Why does the electrons get less dense when the cat moves in frame with them then? Shouldn't their mutual repulsiveness space them out evenly again?

Love it!!!

richard meagher oh goood noooo. Why. Why???????

richard meagher if he wanted you be a idiot, he say, "all know it all's comment Bellow"

Pawsitively charged

@@fgvcosmic6752 Oh this went way fur ther than I thought it wood. Joy!

isnt that like an insult?? that one should move at high speeds to perceive you as slim ,i.e you hella fat XD

From our point of view there is a magnetic field due to the current which is why the cat is also repelled

@@Blegie he means, when the cat is not moving. In the Video he says, that there is no force on the cat, but the electrons are moving and should be contracted out of both perspectives.

i was looking for this comment

@Fabian Wittmann yes exactly. And also, he says that the flow of electrons is ever so slightly spread out from the point of view of the moving positively charged cat. Is that right though? There’s no such thing as reversed lenght contraction right?

I Completely AGREE. In fact we should start demanding the link to the papers or demonstrations, otherwise these animations are just misleading or incomplete

electromagnetism is analogous to you moving a spoon in a cup of coffee. if you move it, fluid from all sides rushes into the lower pressure density area right after the displaced fluid. the whole universe is a fluid, charges are a measurement of fluid (or its pressure) density around matter , which in itself is just stacked fluid waves locked in a standing wave motion by having just the correct wavelengths to perpetually push each other, and whos perpetual movement creates a perpetually lower fluid pressure density around the standing wave, which is called gravity on the subatomic, incoherent scale, and magnetic field when only looking at the stacked force of coherent pull from all the tiny mass units which are aligned to pull together in magnets. there is no need for any kind of relativistic nothing. the amount of charge density might be the same in the entire wire, but the moving charges create an area with lower charge density right behind the displaced charges, which compels the charged behind them and in front of them to move, causing a chain reacting in the wire. the non zero local charge density comes from the transmitted pressure impulse creates by the battery, or more specifically the induced movement. You could use relativistic language to describe this, but it is just semantic confusion for something very simple. you dont stir your coffee with the speed of light, but it still makes the coffee in your cup implode into the center of the lower pressure created by you moving the spoon. you would not use relativistic language in that case, yet the same implosive field is created, just in another medium. the faster you move the more implosive the coffee becomes, and if you were fast enough and pushed only in one direction, a vortex would form that would approach a phi golden vortex spiral more and more with increasing speed. a magnetic field made visible in 3 dimensions looks like a double phi golden ratio vortex, cause it is an implosive field . In text books, the spiral shape is not shown, and the field lines are instead depicted as straight, but thats not true and comes from only doing visual experiments on a 2 dimensional plane, which doesnt show the golden ratio vortices. my point is that its all just changing pressure and fluid dynamics. the entire universe is just a single unified superfluid with its waves forming standing waves, and all fields are just pressure differencials ultimately caused by perpetual standing waves creating perpetual areas of lower pressure, and them stacking on top to appear particle like on a larger scale. in reality, the electrons moving in the wire do not exist as countable units, they are actually an amount of fluid literally flowing through the wire after getting pushed out of their pressure neutralizing areas around the standing waves which form the copper atoms, and that movement creates an implosive force around the wire just like in the cup.

xD

exactly!

even adult cant understand

I never understood too... And now I do

@@JanKowalski-wb2fv i still dont haha. here he has a moving charge. but what happens when i put a magnet here? does it have moving charges and thats why its gonna have a “magnetic field”?

+djscurge that's why you should study physics and not just EE

+djscurge, I came across this in an intro EM textbook at Uni and it blew me away. It was like a "holy crap, of course" moment. But Maxwell's Eqns were like a beautiful derivation based on laws found from experiment, whereas the Relativity argument was more like a logical derivation from first principles.

+UteChewb Wow. Can I know which EM textbook you is it?

loo xavier This was a long time ago but I kept the book because it was so amazing. It is "Electromagnetic Fields and Waves" by Lorrain and Corson. It not only has a solid treatment of EM but it has plenty of examples with detailed explanations. Googling, it appears there is a pdf of the 3rd edition available on the internet. The text gives an in-depth (intermediate level) intro to electrostatics and then before getting into magnetism it covers special relativity. :) I'm sure there are more up to date texts available but I don't know them.

+djscurge Don't feel bad about your university curriculum. This is not something that you can teach freshman or even juniors right away. It takes some time to be able to recieve and understand it. This is honestly not something that would be relevant for most EE programs - we teach it to Physics students in their third year.

If the electrons contract but the space around them doesn't follow-up, what is there between the end of space and the electron? And does it occupy no space to not create distance? wtffffff Ok, it's late here now, am I confusing things?

Ropbastos I'm researching this right now. If you want to PM me (if that's possible on KZfaq), I could show you what I've found and we could discuss it.

Ropbastos It's the protons that contract, and it's space itself that is contracting. You've got to remember it's not just the time that is relative, it's space AND time that are relative. That's what the illustration of the squished car was all about. From one relative framework (stationary observer watching moving car), the car is squished. From another framework (moving car watching stationary observer), it isn't. In fact, it's the outside observer who is squished! It's not a perception thing, either. Any means of measurement the stationary observer uses to measure the car comes up with a shorter length than the driver of that car would find if measured from his own frame of reference. The car is literally shorter for the stationary observer. So for the cat and the wire, the protons in the wire really are closer together than the electrons when the cat is moving, causing the positive cat to be repelled by the now slightly positive wire. From a stationary observer's perspective, however, the wire remains neutral.

Jeffery Wells "From the stationary point of view, however, only the electrons themselves are moving. This only means that the electrons are squished down a bit and get flatter, but the space between them (again, the conducting wire) is stationary." I'm referring to this part of the main comment. From "Derek's" pov it would be the electrons contracting, no?

By the analogy in the video, when the camera is stationary, the car squishes while the space (background) remains unchanged. But when the camera moves, the whole space is moving backward in it's frame, so the whole space (background) squishes, hence making its content (positive ions in case of wire) less dense. I feel so happy right now as well. Thanks for helping, Volbla. :)

Bro he is not Feynman but einstein

Nah it was Feynman.. check it

"We stumbled on this archival BBC interview with American theoretical physicist Richard Feynman over the weekend, and just couldn't stop watching. Filmed as part of the 1983 TV program Fun to Imagine, the interview takes a rather tense turn when the interviewer poses what I'm sure seemed like a very simple question in his head: If you hold two magnets with the same poles close, you'll feel a force pushing them away, and if they have opposite poles, they will snap together. "What I want to know is, what's going on between these two bits of metal?" he says, as Feynman does little to mask his annoyance. "Why are they doing that, or how are they doing that?" For those who haven't seen this clip before, Feynman's response to what anyone would consider a perfectly reasonable question is somewhat off-putting. To be perfectly honest, Feynman initially comes off as a bit of a jerk whose "delicate genius" has been needlessly disturbed. But through his obstinance, Feynman admits that it's actually an excellent question, but one he simply cannot answer in terms that a layperson can understand. "How does a person answer why something happens?" Feynman responds, before launching into an analogy about "why" Aunt Minny slipped on some ice and ended up in hospital. Just as you can't fully explain that scenario without discussing the fundamentals of fluid dynamics, and why you can't properly answer "Why is the sky blue?" without also explaining the concept of Rayleigh scattering, he says you can't explain why magnets behave the way they do to a layperson without first explaining the concept of electromagnetic forces to them. And who knows if they'll even understand that? Feynman tells his interviewer: "I can't explain that attraction in terms of anything else that's familiar to you. For example, if I said the magnets attract like as if they were connected by rubber bands, I would be cheating you. Because they're not connected by rubber bands ... and if you were curious enough, you'd ask me why rubber bands tend to pull back together again, and I would end up explaining that in terms of electrical forces, which are the very things that I'm trying to use the rubber bands to explain, so I have cheated very badly, you see." www.sciencealert.com/watch-richard-feynman-on-why-he-can-t-tell-you-how-magnets-work

@@Chicken_Little_Syndrome he couldn't explain it to an average person and washes hands saying that they're so average and uneducated that they have to understand principles behind it that they're also too much for their little mind? He's not wrong, but it's no excuse for someone on the "TOP" of historical scientists and idolatred icon and for anyone "educated".

It was *Einstein!!*

Eczacly!

bonjour

Which language do you prefer???

Which language do you speak?!

In India, Juli is a Dog's Name.....😆😂🤣🤧😅

@@gopalkrishna3803 I think it's a very disrespectful comment. Don't downgrade India's name please

+Michael Englo It is a mistake in the video. With the cat not moving with respect to the atoms in the wire, the positively charged ions (atoms) appear to the cat at the expected distance, whereas the electrons moving past appear to the cat foreshortened and closer together, and therefore a net negative charge from the cat's point of view. So yes, you are correct, the stationary cat feels attraction to the stationary wire with negative electron current flow.

+Steve Greenfield Someone else in the comments explained that that's not correct. According to special relativity, the electrons themselves would experience length contraction in the stationary cat's frame, but the space between them would not since it's not the space that's moving relative to the cat. Electrons are essentially point charges, so the length contraction of an electron itself has no effect, and the wire remains neutral in the stationary cat's frame.

The length contraction affects the electrons as a group, because they are moving as a group. The spacing appears the same from the electron's frame of reference, but the group has shrunk in length from the cat's point of view.

Actually, someone else had a better explanation. In reality, both the nuclei and the electrons are moving. In the stationary cat's frame, the nuclei move back and forth but the electrons move around in a way that almost immediately neutralizes any charge imbalance caused by the movement of nuclei, even when a current is flowing, so that the wire remains electrically neutral. When the cat is moving, however, there is no way for the electrons to neutralize the charge imbalance since the electrons appear less dense than the nuclei.

There is no difference. Imagine this: Reverse charges in the wire, with a stationary cat. Stationary negative charges, positive charges moving to the right, stationary positive cat. From the cat's reference frame, negative charges appear normal. Positive charges appear to be closer together and so the cat is repelled. This is exactly the same as the cat moving to the right with the negative charges moving to the right at the same speed. When speaking of something as stationary, this is misleading. Because you can only speak of motion in relation to some other frame of reference. So a stationary cat is a cat stationary with respect to -you-, but you aren't part of the picture. The cat is either stationary with respect to the wire, or stationary with respect to the electrons. In each case, everything that is moving relative to the cat appears to the cat as subject to Lorentz contraction. That includes the entire universe. www.mtholyoke.edu/courses/tdray/phys310/electromag.pdf

Alan Jay Its called an youtube loop.You are stuck for eternity.

Arghya Sen Awh Naaaaawwwwwwwwh!!

+Alan Jay LOL omg

+Alan Jay Want to know how to keep an inquisitive KZfaqr busy?

+Alan Jay, That's what you get when two great persons collaborate.

Break the loop check out Quantum Atom Theory!!!

> Click here < to escape the loop. There you go. You're welcome.

Do not worry my suggestion-abiding friend! CTRL+F4 will break the cycle!

Destroy the power plug and incinerate your computer. Problem solved.

Because the animation in the video is misleading. In reality, you should visualize the positive charges as holes that move opposite to electrons. So they both have equal and opposite velocities so the net effect will make the wire neutral in charge

You need to go to back to Maxwell and ether and magnetism separated from electricity. Read Robert Sungenis.

The electrons all move on separate trajectories such that their spacing is unchanged . They do not constitute a solid object subject to relativistic stresses

​@@DrDeuteronif that would need true it would be unaffected by the moving cat as out would not change. Motion is relative. From the cat perspective it is never moving. The electrons in the wire only change speed and it direction

I think that special relativity is also applicable to the space time fabric as a whole along with subatomic particles like the proton and electrons and also the members of the elementary particles.

Thanks very much.. I have been very confused about this from a long time

Thanks for the explanation. I immediately looked into the comment section expecting that someone must have addressed this issue.

@@shashankknp smart bro

that is, when a rocket flies at a sublight speed, shrinks not the length of the rocket (from nose to tail) visible by us, but the atoms of which it consists?

Déjà vu

it's just that narrator's frame of reference doesn't matter to the cat and the wire.

Indeed. The explanation is ridiculous.

Thank you so much for the explanation, man!

Just one problem with that: in a metal, we don't explain conduction using holes. Not that it's relevant to your explanation but it's just an FYI.

YiFan Tey there are no "holes". The positive charges are the positive ions in the metallic lattice.

Guillaume Lemaigre No - that confused me too at first. If electrons are moving right, protons are moving left. There's a sea of ions, positiv and negative, and electron drift also results in positive charges drifting in the opposite direction. From a still point of view, both contract in the same magnitude, and so there's no net charge.

Steven Wang No. That's wrong. In the stationary cat's frame of reference the protons are not moving!

ricomajestic Well, not necessarily the protons are moving. But with electrons moving to the right, essentially positive charges are moving left. Take a neutral charge and a positive charge: ± + Suppose the electron jumps to the right: + ± The electron has jumped to the right, but essentially, the positive charge is moving left. So you're right - no, the protons don't move, but yes, the positive charges are moving left as the electrons move right.

Steven, it depends on the frame of reference. From a stationary cat frame of reference (i.e.- a cat that is not moving relative to the wire), the protons are not moving but the electrons are moving to the right. However, from the electron's frame of reference the protons (and cat) are moving to the left.

Steven Wang Ok that's much more clear. But still... Just explain me why an electromagnet atract then a piece of metal (like iron). Because the iron is not moving but is still attracted... it just feels like it contradict itself somewhere. (i know for sure that magnetism is really well explained by relativity in term of moving electric charges, but on the concept side, it's not clear to me.)

I thinks, bcz of drift velocity are very very small w.r.t to normal movement...

This is because the wire tries to remain neutral under a current so the "real" density of electrons has to decrease slightly to keep the zero charge with the moving electrons. The protons are not moving so they determine the new density of electrons, which has to be the correct one to keep the wire neutral. That's the reason that the proton outside the wire sees no charge when it's not moving relative to the protons. (Sorry for my english)

Lot of confusion here stems from a little oversimplification in this video. The positive charges--or rather, the distribution of positive charge--is in reality not actually static but moves in the *opposite* direction as that of the negative charges. Basically, you can loosely think of it as if an electron migrates away from a nucleus in some direction towards some other positive charge then it's former location because more positive, while the latter becomes more neutral. So, you have like a net negative charge movement or stream in one direction, together with a positive-like charge movement or stream in the opposite direction. So, from a rest charge perspective these opposing streams merely cancel one another out and the so-called "current-carrying" wire overall actually appears simply neutral. But, if that external charge happens to *just so ever budge* into the direction of one of these streams, then it will experience that whole associated effect (magnetic repulsion or attraction) due to the length contraction phenomenon presented in this video.

@@MikeSmith-vb8ul Thank you. Your clarification really helped me out.

@@MikeSmith-vb8ul By that logic, if the cat-ion moved in the same direction as the protons, it would "see" the electrons moving in the opposite direction and thus become more densely packed. And so it would be attracted to them... But that's not what actually happens, is it?

Thanks! I was really confused and the comment sections of those questions were filled with hate comments (unlike most science vidoes)

You're welcome.

not convincing. Good for the try though. This question needs addressing

The actual nature of conduction only obscures this thought experiment. Here, electrons move on trajectories such that their spacing is unchanged, by definition.

A not moving metal object has metal atoms with electrons circulating around them. This creates a "magnetic field" for every atom (called magnetic moment, not literally) which lines up with other such magnetic fields of other atoms to temporarily create a magnet with two poles (given if the metal shows paramagnetism)

A circulating electron is like current across a circular loop, so like a ultra small version of a solenoid

@@mukherjee.p exactly, magnets. But in the video he presents a charged particle not an magnet.. and isn't this only a phenomena with AC current? I'm also confused

@@ivarnyman3417 Well Yeah but not only for AC. Any moving charged particle produces a magnetic field (on top of the electric field it already had). You move an electron (somehow) (doesn't even have to be in a circuit or anything. Simply moving it through space) and it'll create a very small magnetic field. That's the theory

magnetic field lines want to be in the (permeable) metal, it lowers the field energy the closer the metal gets to the magnetic. Energy changing with position is a force.

I'm gonna just copy and paste a response from another person answering virtually the same question. He explained it really nicely. From "Bob Badeer" a couple of months ago: "In Derek's reference frame, yes electrons are moving and the distance between them is effectively 'slimmer' in his reference frame. But consider this, overall the wire is also neutral. It has to be since applying an electrical current doesn't make a conductor ionized (non neutral) overall. So what's going on? Each time an electron moves from atom A to atom B, atom A has lost 1 electron (it is now positively charged) while B has gained one more electron (it is now negatively charged). It's as if atom B gave a positive charge to A instead of A giving an electron to B. That positive charge is an electron hole. Think of it as money. You have a 100$ bill and I have none. I give a -100$ bill to you : it cancels out your 100$ bill making your net worth 0 while I have lost a -100$ making me richer by a 100$ (2 negatives make a positive). Wealth hasn't been created nor destroyed, only transferred. When an electron moves from A to B, an electron hole moves from B to A at the same time. So in Derek's frame, electrons are moving but holes are also moving at the same speed (thus having the same relativistic effects) making it neutral. In the cat's frame, electrons aren't moving anymore but holes are moving in the opposite direction twice as fast making the wire clearly positively charged thanks to relativistic effects. If you reverse the current, you'd reverse the direction in which holes and electrons are moving. In this scenario, electrons are moving in the opposite direction while holes are stationary in the cat's frame. That is why inverting polarity inverts the magnetic field. Now clearly, the absence of an electron isn't a real particle : it's just a region of space with no electron in it. So where does this positive charge-like effect comes from? From the atom's protons. Remember, we are talking about atoms here and atoms are made up of negative charges (electrons) and positive charges (protons). So when an atom has less electrons than protons, it is ionized (cation or positively charged)."

That explanation 8sn't satisfactory either. If the positive charges come from the protons, then the positive charges are relatively stationary in the wire....thus no relativistic effects for things in the wires inertial frame. The explanation is insufficient to explain any number of real world phenomena: -even without protons, for example electrons shot down an evacuated tube, the magnetic field is created and will alter the path of moving charged particles. -nothing in the original explanation of follow up attempts explains why a charged particle moving directly toward or away from a current carrying conductor experiences a force that turns it away from directly into or away from the wire. If it were correctly modeled by electrostatic attraction/repulsion, the path would not experience this turning.

Ben Griffin I agree, I don't think that happens, because it's like watching a screen, even if you see a jet dash away in a movie, nothing's really moving, the led lights just turn on in sequential order so the positive charges aren't really being length contracted.

Dont worry. Most stuff makes no sense in Einstein theories. If you start to consider them seriously and not as an abstract you will get to paradoxes, division by zero, infinite densities or zero volume and negative radius etc. No wonder Nobel committee did not gave him Nobel for that.

oldi184, says the guy who has "100 Reasons Why Evolution is So Stupid" in his playlist.

exactly Ben; no preferred inertial frame of reference; they can't even memorize the things they were supposed to memorize, let alone question those things

I agree, this explanation makes no sense. When the cat is stationary, the moving negative charges shall contract and attract the cat.

@@TheMyrkiriad I'm just going to point out that he did say we should assume that at a "stationary" perspective the positive and negative ions had identical density... ( 1:15 and 1:32 ) So, no It shouldn't be attracted.

I was going to type something similar but you've got it covered. These people spewing this pseudo intellectual nonsense are really starting to do my head in.

@@mysty0 I notice how nobody in this two year old comment thread actually linked a better explanation or did anything except go "nuh uh!" Also, Jimeny Christmas, people. It's a 4 minute video, not a semester long lecture on quantum effects and fundamental forces. If any of you putzes have a better explanation, I'm all ears, and I'm sure the creators are, too.

This is the fun part. Mathematically, quantum electrodynamics is by far the best model we've got, but it's cutting edge. I mean, we know fields occupy space, possess energy and momentum, and interact with each other, but we just don't know yet whether they're made of anything more fundamental than themselves, nor if "field" even gives an ideal picture of what's going on. But assuming it does, a particle is a sustained oscillation propagating through spacetime. Each particular type of particle has a corresponding field. Electrons are oscillations of the electron field, and they continually cause momentary fluctuations/disturbances in the electromagnetic field (the field for photons). These disturbances can't be detected directly as they don't have all the right traits to become particles, so we call them a virtual particle and debate whether or not they exist. One way to imagine it is that all the possible positions in spacetime have a state, and each field is like a huge spreadsheet woven throughout, applying formulas to every position. Due to the uncertainty principle, we can't pinpoint an exact position, there are fluctuations everywhere, and the smaller the region we try to observe, the bigger those fluctuations get. With a normal object, the momentary disturbances aren't aligned in any special way so their effects are cancelled out. However, a magnet's unpaired electrons have been aligned so that they have the same 'spin', the effect being that they disturb the electromagnetic field in a consistent way. Electrons of certain other objects then acquire momentum in a common direction when they absorb the disturbances (which are otherwise reabsorbed by the magnet). The arrowed lines drawn coming out of the material and back in show the direction that the acquired momentum goes. But the disturbances themselves reach outwards in straight lines from the magnet in all directions.

Classical electromagnetism doesn't reflect physical reality, it's just a (really good) mathematical model. Even quantum field theory seems to fall apart in certain circumstances, so we don't have an absolute picture of reality. This is frustrating, but I think being able to visualize electromagnetic waves and fields is still really useful.

I like the Thunderbolts project. They have hundreds of videos trying to illustrate what electricity and magnetism could be. The best I've heard is that magnetism is an effect of ions interacting linearly, instead of in a waveform, with the "ether" (space-time.) People don't like that word because it's archaic. But, I understand that a fundamental geometry of reality has been "found" and that's what I think they mean, even if they don't realize it. Anyways, it's been illustrated that the magnetic force is similar to tugging a rope and feeling the effect, as apposed to whipping the rope and waiting to feel the wave, on the other end. This is why there is an "instantaneous" effect when compared to something with a "limited" speed such as light.

look up Magnetism - Ken Wheeler: kzfaq.info/sun/PLjz0SgxcrlEbksk1t13CfZt1p6F8wg2ZH

Electricity and magnetism oppositional forces. They are the same differing only by degree and temperature. When what a magnet approaches absolute zero, it's loses electrical potential and becomes heavily magnetized eventually entering a Quantum locking state were you can position the magnet in three dimensional space and it will remain locked in that position like you were holding it with clamps. Inversely the hotter the metal becomes the more charged the electrical potential increases and the less magnetic it becomes until it reaches its Curie temperature at which point loses magnetism. Everything in science can be thought of in this way, everything has a pole and an opposite Force which is exactly the same, but separated by degree. You can think of magnetism/electricity like an ethereal water, it works very similar. Water evaporates off of the surface of the ocean into hot humid air which condenses into water which then falls to Earth where it is absorbed and eventually mkes it was back to the ocean. A magnet exposed to changing or oscillating poles creates a magnetic field which like evaporation fills the air with electrical potential (humid air) which then collects or inducts the electrical out of the air and and eventually returns to ground or earth.

***** It doesn't. mindstormmaster The density of the moving electrons is not higher. The electric field from the voltage source, which causes the electric current, accelerates every electron in the same way, leaving their distance unchanged as measured in the rest frame of the stationary charge. Consequently, due to special relativity the distance of the electrons must be greater in the rest frame of the electrons.

Omg i haughed so hard XD

lmao

nice one

I had a nice laugh at that

LMAO

+Daniel Hale *keep thinking happy thoughts we just might be able to fly away!!*

+Daniel Hale Oh, but that will never happen.

+Daniel Hale PREACH BROTHER!!! RISE AGAINST THE CATS!!!!!!!!!!!

Your positivity would attract negative cats.

actually, (cations) are pawwsitively charged!

but this is a special case, where Derek has F_0j = F_j0 = 0, where F_ij = -F_ji is non zero, and a four current with J_0 = 0 and J_z non-zero, then he transforms it to Henry frame where everything is nonzero, except the electron's 3-current vanishes. The most sensible way to say it is that Henry's electric field is a transform of Derek's magnetic field (because Henry's positive charge density is a transformation of Derek's two canceling J_0's that only cancel in Dereks frame). fwiw.

I have seen this bad generalization in textbooks, now people repeat this everywhere and its difficult to revert the misinformation.

@@DrDeuteron indeed, but then they use this special case to say something general about how electric fields transform. The problem here is that they are trying to explain a relativistic effect with classical ideas.

Ya i have the same question, if you find the answer plz tell me

I was also looking for this same doubt in the comment section and got yours..

We share the same brain

No because the SPACE between electrons in NOT moving and electrons themselves have no size.