The screw nature of electromagnetism

[Farsight]

Yes. Are you sure you've understood what that means? Because you've got a lot of bizarre ideas about how to go about trying to convince a physicist of something.

Like showing them the references and the evidence and putting up a robust argument that nobody can counter?

That's a myth.

It's no myth. If you think you understand something but you cannot elucidate that understanding, then you are fooling yourself. And as you know: "The first principle is that you must not fool yourself, and you are the easiest person to fool".

Insisting on adherence to what famous physicists said is ideology.

I'm not insisting on it, I'm pointing it out, and guys like lpetrich dismiss it out of ideology.

Except that $$\bar{E}$$ and $$\bar{B}$$ don't have the SI units of force and they aren't the time rate of change of momentum of anything, which is what the word "force" is normally taken to mean in physics, as I already explained to you. You've given no explanation whatsoever as to why $$\bar{E}$$ and $$\bar{B}$$ should be called "forces" and why it would be wrong to call them "fields". You just copied something Minkowski said.

I gave the explanation in the OP. It isn't just "what Minkowski said". it's also things like this:

"The electric field is a vector field. The field vector at a given point is defined as the force vector per unit charge that would be exerted on a stationary test charge at that point".

If you only have one charged particle with its electromagnetic field, there's no force upon it. Only when you add another charged particle do you see any force. When that force is linear you say an electric field is present. But what's actually present are two electromagnetic fields, interacting.

Who says they do? Google turns up only a handful of hits for an exact phrase search for "hydrogen atoms twinkle", all of them to posts written by you.

CERN. I can't find it right now, but there was a CERN video showing "messenger particles". The electron and the proton both emitted a outward spherical stream of photons.

You've got no evidence or supporting theoretical analysis showing that the electromagnetic field can even be interpreted as a state of curved space, let alone any basis for presenting it as if it were an established fact.

I can't present it as an established fact, but I can point out Maxwell referring to displacement current and "transverse undulations" when he's talking about light. When a seismic wave moves through the ground, the ground waves. When a swell wave moves through the ocean, the ocean waves. When an electromagnetic wave moves through space, space waves. You might want to look at LIGO by the way.

 

[Farsight]

On the face of it the idea doesn't seem workable. A small body affected just by spatial curvature should normally just follow a geodesic trajectory...

You aren't seeing the big picture. Let me try to get it across via an analogy. Imagine you're standing on a headland, looking out over the sea. It's flat calm, glassy like a mirror. On your left is an estuary, on your right is the open ocean. So there's a salinity gradient from right to left. After a while you notice something out to sea, coming towards you. At first you wonder if it's a small body such as a boat. But then you realise it isn't a "body" at all. Instead it's a wave, just one, all on its own. You plot its course, and you come to appreciate that its path is slightly curved. It's curving slightly towards the right because of the salinity gradient. This wave is standing in for a photon. Its path is curved because the water density isn't uniform. The water is standing in for space. The path of the wave through space over time is curved, so we say spacetime is curved. Now look back to that wave moving across the ocean. Look closely at the surface of the sea where that wave is. See it?

It's curved.

But what experiments keep confirming is that a charged body in the presence of an electromagnetic field is deflected according to the Lorentz force law, meaning that the equation of motion (for velocities much less than c) is

$$\frac{\mathrm{d}^{2} \bar{x}}{\mathrm{d}t^{2}} \,=\, \frac{q}{m} \, \bigl( \, \bar{E} \,+\, \bar{v} \,\times\, \bar{B} \, \bigr) \,.$$​

The motion is different for +ve and -ve charged particles, and for neutral particles. So you know that something about the particle governs its motion. You ought to be able to spot the similarity between the motion of "spinors" and the motion of vortices.

The geodesic equation predicts coordinate acceleration that depends quadratically on the coordinate velocity and independently of a body's properties such as its charge and mass.

Quite. Gravity isn't the same as electromagnetism.

By contrast, the Lorentz force law predicts a constant contribution to the acceleration and a contribution that depends linearly on the velocity, but no quadratic term, with the magnitude of the deflection depending on the body's charge-to-mass ratio.

Because the body is comprised of a collection of +ve and -ve and neutral particles.

So if you are going to claim that the electromagnetic field can be thought of as curved space, it would fall on you to explain in detail exactly how that idea is made to work (or point to where that analysis has already been done by someone else), including how it correctly predicts the trajectories of macroscopic charges in a way consistent with the Lorentz force law.

I've gone some of the way in the OP. But maybe I need another thread for this, where I talk about four-potential and displacement current, and how potential is more fundamental than field, see Wikipedia re Feynman. And how the messenger particle is more fundamental than the force it is said to mediate. Meanwhile note that it's the Lorentz force law.

 

[origin]

Farsight you really need to learn the words, "I guess I was wrong". Then you could move on, not to mention you could learn more.

 

[PhysBang]

I have [studied the math of electromagnetism].

Great!

Can you please show us how to use your pictures to derive the specific equation of motion for a charged particle in a simple system?

 

[CptBork]

I referred to it earlier in the thread in response to CptBork's challenge, but he backed down.

No, I'm still waiting for you to actually do something with it. You wrote down Faraday's law and said "tada!" Now I'm asking you to derive it for us using your ingenious fingerpainting model. Or how about you show us why the static Ampere's law can't be true in general without the addition of a changing electric flux, demonstrate that it's worth spending more than 10 seconds talking about Maxwell's equations with you?

 

[przyk]

Like showing them the references and the evidence and putting up a robust argument that nobody can counter?

You gave a rapid-fire succession of links and references in your OP without explaining the relevance of or connections between any of them. There is nothing in your OP that anyone could make a prediction from, so it is trivial to counter it: you simply haven't met the most basic requirement of a scientific hypothesis.

It's no myth. If you think you understand something but you cannot elucidate that understanding, then you are fooling yourself.

Why should that be true? That's the thing about myths: they're things that people just accept as true without really thinking about them. So why should one's ability to explain a technical subject like physics be a useful test of understanding of that subject?

And as you know: "The first principle is that you must not fool yourself, and you are the easiest person to fool".

That's from Feynman's cargo cult science essay, in which he discusses a lot of ways scientists and the general public can fool themselves, none of which have anything to do with explaining things to grandmothers.

I gave the explanation in the OP. It isn't just "what Minkowski said". it's also things like this:

"The electric field is a vector field. The field vector at a given point is defined as the force vector per unit charge that would be exerted on a stationary test charge at that point".

So the electric field isn't a force then. The electric field vector multiplied by a particle's charge is a force.

Similarly, in Minkowski notation, a particle's charge multiplied by the Faraday tensor and its four-velocity gives the four-force acting on it, but the Faraday tensor itself is not a force.

 

[Farsight]

No, I'm still waiting for you to actually do something with it. You wrote down Faraday's law and said "tada!" Now I'm asking you to derive it for us using your ingenious fingerpainting model. Or how about you show us why the static Ampere's law can't be true in general without the addition of a changing electric flux, demonstrate that it's worth spending more than 10 seconds talking about Maxwell's equations with you?

The static Ampere's law is $$\nabla \times \bar{H} = \bar{J}$$. What do you want me to say? That the "equals" is an "is" rather than a "creates"? That the curl or rot short for rotor is there because of the screw nature of electromagnetism? Or how about if we get down deep and fundamental, and I tell you we're dealing with dynamical spinors and nothing is really static? That the electron is said to have a magnetic field because it's a photon configuration and the photon is alternating displacement current? That a motionless electron is static current that isn't really static?

 

[przyk]

You aren't seeing the big picture.

Huh? I'm drawing attention to the first thing one normally learns about electromagnetism: that an electromagnetic field, whatever it might be, pushes and deflects macroscopic charged particles around in a very specific way described by the Lorentz force law. If you can't recover that -- and it's literally highschool physics we're talking about here -- then you haven't established any connection between your "big picture" and reality.

The path of the wave through space over time is curved, so we say spacetime is curved.

No we don't. We say "spacetime is curved" because someone developed a detailed theory about what things would be like if spacetime were curved, and that theory was found to be in quantitative accord with a number of experimental observations including all of Newtonian gravity.

If it were just for the qualitative observation that light bends, there could be any number of reasons for that and there would be no particular reason to settle on spacetime curvature as the best explanation. Light bending alone is very little to go on.

I don't think you appreciate just how much quantitative evidence and detailed analysis goes into supporting a typical mainstream theory. Because it's vastly more both in quantity and in level of detail and rigour than what's in your OP.

Because the body is comprised of a collection of +ve and -ve and neutral particles.

So how are these modelled, how is spatial curvature modelled, and how do you recover the behaviour predicted by the Lorentz force law from that model?

These are things you should have been able to explain in your OP right from the beginning, if you were expecting it to be taken seriously by physicists.

 

[Farsight]

You gave a rapid-fire succession of links and references in your OP without explaining the relevance of or connections between any of them. There is nothing in your OP that anyone could make a prediction from, so it is trivial to counter it: you simply haven't met the most basic requirement of a scientific hypothesis.

It isn't a hypothesis. It isn't some new theory. It's an explanation, that's all. And this is just a discussion forum, not Nature Physics.

Why should that be true? That's the thing about myths: they're things that people just accept as true without really thinking about them. So why should one's ability to explain a technical subject like physics be a useful test of understanding of that subject?

Allow me to demonstrate: explain the linear attraction and rotational motion of charged particles in mutual proximity.

That's from Feynman's cargo cult science essay, in which he discusses a lot of ways scientists and the general public can fool themselves, none of which have anything to do with explaining things to grandmothers.

You can't explain something, and you're dismissing my explanation. Now, go and find a mirror, look at yourself in it, and say this: "Both the Einstein quote and the Feynman quote are relevant to me".

So the electric field isn't a force then. The electric field vector multiplied by a particle's charge is a force.

Huh? There is no electric field. You have two (or more) electromagnetic fields. Each charged particle "is" field. Field interactions result in force. The more field, the more force.

Similarly, in Minkowski notation, a particle's charge multiplied by the Faraday tensor and its four-velocity gives the four-force acting on it, but the Faraday tensor itself is not a force.

No. It's "a mathematical object that describes the electromagnetic field of a physical system". A tensor is a matrix. An electromagnetic field is a state of space. The map is not the territory.

Time for tea przyk.

 

[Farsight]

Huh? I'm drawing attention to the first thing one normally learns about electromagnetism: that an electromagnetic field, whatever it might be, pushes and deflects macroscopic charged particles around

Aaaaargh! It takes two to tango! There is no magical mysterious action-at-a-distance. A charged particle moves the way it does because it's a dynamical spinor. And it is field, it isn't some little billiard-ball thing. It isn't a point particle. You can diffract electrons. And a boomerang doesn't go round in a circle because there's something pushing it round.

...in a very specific way described by the Lorentz force law. If you can't recover that -- and it's literally highschool physics we're talking about here -- then you haven't established any connection between your "big picture" and reality.

The Lorentz force law is just that. It's not the Lorentz field law. Look at the opening sentence on Wikipedia and permit me to change point charge to charged particle: the Lorentz force is the combination of electric and magnetic force on a charged particle due to electromagnetic fields. Yes it goes on to say electric field E and a magnetic field B, but you know from Jackson that one should talk of the electromagnetic field Fuv. And see lower down: "A positively charged particle will be accelerated in the same linear orientation as the E field, but will curve perpendicularly to both the instantaneous velocity vector v and the B field according to the right-hand rule". Why? Because they're throwing photons around? That's cargo-cult science przyk. You can't give that explanation to your grandmother. She'd laugh you out of court. She'd tell you you were fooling yourself.

No we don't. We say "spacetime is curved" because someone developed a detailed theory...

Quit carping.

If it were just for the qualitative observation that light bends, there could be any number of reasons for that and there would be no particular reason to settle on spacetime curvature as the best explanation. Light bending alone is very little to go on.

Whoa. Light doesn't curve because spacetime is curved. Go and read that gravity thread.

I don't think you appreciate just how much quantitative evidence and detailed analysis goes into supporting a typical mainstream theory. Because it's vastly more both in quantity and in level of detail and rigour than what's in your OP.

I appreciate it. I'm the one who read all the original material by Maxwell and Minkowksi and Einstein etc.

So how are these modelled, how is spatial curvature modelled, and how do you recover the behaviour predicted by the Lorentz force law from that model?

These are things you should have been able to explain in your OP right from the beginning, if you were expecting it to be taken seriously by physicists.

I tell you what, I'll do all the details so that you will take me seriously. Only once I've done that, I won't need you to take me seriously. And more to the point, nobody will need you.

 

[CptBork]

The static Ampere's law is $$\nabla \times \bar{H} = \bar{J}$$. What do you want me to say? That the "equals" is an "is" rather than a "creates"? That the curl or rot short for rotor is there because of the screw nature of electromagnetism? Or how about if we get down deep and fundamental, and I tell you we're dealing with dynamical spinors and nothing is really static? That the electron is said to have a magnetic field because it's a photon configuration and the photon is alternating displacement current? That a motionless electron is static current that isn't really static?

Why get into fancy concepts you don't understand, like spinors and photons, when I'm only asking you to demonstrate something much simpler? First off, $$\vec{\nabla}\times \vec{H}=\mu\vec{J_f}$$ is the static version of Ampere's law in linear diamagnetic materials. The general version which works under all static situations is $$\vec{\nabla}\times\vec{B}=\mu_0\vec{J}$$. But let's take your example, where you work with the Helmholtz field, denote your vectors with bars and choose units in which the magnetic permeability is 1. Show me why the law you wrote down in your notation, $$\nabla \times \bar{H} = \bar{J}$$, in which $$\bar{J}$$ is the unbound free current density, cannot apply to diverging free currents.

Hint: this is a joke for entry-level physics people, so if you're not an arrogant ignorant ninkompoop, you should have no trouble answering it. There is a very simple, straightforward mathematical reason for the answer which has nothing to do with any known experiment, and that's what you should be able to demonstrate (unless as I suspect, you really know dick about Maxwell's equations, vector calculus and electromagnetism).

 

[Farsight]

Because divergence is "outgoingness" and the current is going round and round. Now go and look at electron magnetic dipole moment and pay attention to "an electron indeed behaves like a tiny bar magnet". Then note that I do understand spinors and photons, and displacement current, and electromagnetism. But you don't, and at this rate you never ever will. Just as you never got to understand gravity. So don't talk to me about arrogant ignorant ninkompoops. Go and read the OP, try to understand it. If you don't, ask me about it. If you want to challenge some aspect of it, feel free. But spare me this feather-spitting outraged hubris.

 

[btr]

A charged particle moves the way it does because it's a dynamical spinor.

If this were true, surely charged bosons (which are not described by spinor-valued fields) would not obey the same laws of motion as charged fermions (which are). This contradicts observation pretty dramatically; both categories of particle are seen to move in accordance with the Lorentz force law and act as sources of electromagnetic fields in the same way.

Also, if this claim were true, all fermions (which are all described by spinor-valued fields) would obey the Lorentz force law. Again, this contradicts observation pretty dramatically; nature furnishes us with many, many examples of neutral fermions.

 

[przyk]

It isn't a hypothesis. It isn't some new theory. It's an explanation, that's all. And this is just a discussion forum, not Nature Physics.

It doesn't matter what the venue is. It's a basic and widely agreed and expected standard of rational discourse that the burden of proof lies with the person making a claim. It's not just a quirk specific to high impact physics journals.

That burden of proof, by the way, is meant to be proportional to the claim actually being made. So if you suggest the idea of the electromagnetic field being curved space and promote it honestly as speculation, you can legitimately just post it without having to prove anything and anyone who reads it has the right to decide for themselves whether they find it interesting. But if you're going to claim it's a workable idea and that the entire physics community is stupid for not already using it and including it in textbooks and graduate physics courses, which is effectively what you did in your OP, then you've really got your work cut out for you.

Allow me to demonstrate: explain the linear attraction and rotational motion of charged particles in mutual proximity.

You're begging the question. You haven't established that my ability to answer such a question (and to your satisfaction, of all people) would be a good test of my understanding of physics in the first place.

You can't explain something, and you're dismissing my explanation.

You haven't supported your explanation. You haven't shown that it actually works.

The simple reality is that, going on your OP alone, no physicist or engineer could adopt your explanation even if they wanted to, because it doesn't model or predict anything.

Now, go and find a mirror, look at yourself in it, and say this: "Both the Einstein quote and the Feynman quote are relevant to me".

You have no evidence that Einstein originated that grandmother quote or that either Einstein or Feynman supported it.

 

[Farsight]

If this were true, surely charged bosons (which are not described by spinor-valued fields) would not obey the same laws of motion as charged fermions (which are).

You can't say too much about that. The only charged "elementary" bosons are the W+ and W- vector bosons, and they have a very short lifetime. So short that their existence has only been inferred. But you can say with some confidence that non-charged bosons like the photon don't move like electrons and positrons in an electromagnetic field. So that surely makes it clear that the particular motion is due to the particular properties of the particle. Then when it comes to "non elementary" bosons like mesons, you've still got spin to contend with. A helium-4 atom is a boson, and whilst the total spin is zero, that isn't the same thing as no spin at all.

This contradicts observation pretty dramatically; both categories of particle are seen to move in accordance with the Lorentz force law and act as sources of electromagnetic fields in the same way.

You're forgetting that some bosons are composed of spinors. Google on proton spinor and think about what He4 is composed of.

Also, if this claim were true, all fermions (which are all described by spinor-valued fields) would obey the Lorentz force law. Again, this contradicts observation pretty dramatically; nature furnishes us with many, many examples of neutral fermions.

Take a look at Neutron magnetic moment. Note that "It is of particular interest, as magnetic moments are created by the movement of electric charges". The total charge is zero, but that isn't the same thing as no charge at all.

NB: Gravity is of course rather different, and rather more "catholic". See this thread to understand how that works. Oh, and welcome.

 

[PhysBang]

It isn't a hypothesis. It isn't some new theory. It's an explanation, that's all. And this is just a discussion forum, not Nature Physics.

Yet people, people who have physics degrees (sometimes PhDs), always point out that the explanations you give don't seem to match how the physics is done. So the burden seems to be on you to show how the explanation you supposedly have matches physics as physicists actually do it. This is something that you refuse to do.

You offer various excuses. I fear that this is because of some sort of mental illness on your part, and I would recommend that you seek help.

 

[CptBork]

Because divergence is "outgoingness" and the current is going round and round.

No, forget about the current going round and round. There is no circulating current in the problem I have shown. Imagine a large bunch of charge at a certain location dissipating off a constant current, with uniform current density $$\vec{J}$$. Explain why it's impossible to find or even invent a field $$\vec{B}$$ which satisfies the equation $$\vec{\nabla}\times\vec{B}=\mu_0\vec{J$$.

 

[btr]

Farsight, I've got some questions about this bit in particular:

E is usually drawn with radial lines of force, and B is usually drawn with concentric lines. There's no problem visualizing them. But there's nothing that lets you visualize the "greater whole". However I think there is a way. A simple way. You just combine the radial and concentric lines. Like this:

<image of "radial lines + concentric circles = spirals" snipped due to restrictions on newbies posting links>

My questions:

1. When you say that the electric field is "usually" depicted with radial lines and the magnetic field is "usually" drawn with concentric circles, I have to point out that the actual shape of the field lines depends strongly on the distribution and motion of the source charges. Notably, for an electron or positron you will not get the type of B-field you depict, you will instead get a dipole field (see reference [1] below). So, for your diagrams, what source distribution did you actually have in mind?

2. How did you arrive at the spiral on the right hand side of your diagrammatic equation? I think it would help me understand what you are trying to do if you explained what exact mathematical procedure lies behind that "addition". Are you literally just plotting the integral lines of E + B?

3. Once you have arrived at your combined spiral picture, which seems to associate a single field value with each point of space, how do you use the values of the new field to compute the force on a moving charge? In other words, if the "addition" process has created a new field C, what type of values does C take (vector, scalar, tensor...) and exactly how do you write the Lorentz force in terms of C and the velocity and charge of a particle?


---

References:

[1] en.wikipedia.org/wiki/Magnetic_dipole

 

[przyk]

Aaaaargh! It takes two to tango! There is no magical mysterious action-at-a-distance. A charged particle moves the way it does because it's a dynamical spinor. And it is field, it isn't some little billiard-ball thing. It isn't a point particle. You can diffract electrons. And a boomerang doesn't go round in a circle because there's something pushing it round.

You've completely misunderstood and failed to address the point of my post: the Lorentz force law is a summary of how macroscopic charges are known, experimentally, to behave in the presence of an electromagnetic field. If you can't recover that mathematically from your idea, you haven't explained even the most basic thing about electromagnetism.

I appreciate it. I'm the one who read all the original material by Maxwell and Minkowksi and Einstein etc.

Reading what famous physicists said doesn't equate to working, functional understanding of the theories they developed.

I tell you what, I'll do all the details so that you will take me seriously.

Just about every physicist who has interacted with you online has -- even if it wasn't always politely -- insisted you should be doing exactly that right from the start. You shouldn't even have had to have been asked for it.

 

[Russ_Watters]

Dig, dig, dig. You should follow origin's advice and just admit you are wrong and bow-out:

It isn't a hypothesis. It isn't some new theory. It's an explanation, that's all.

Ehem:

Theory is a group of ideas meant to explain a certain topic...[emphasis added]

You say it isn't a theory, then you define it to be a theory.
http://en.wikipedia.org/wiki/Theory
And:

A hypothesis (plural hypotheses) is a proposed explanation for a phenomenon.

If you proposed your idea as an hypothesis - a proposed explanation, you'd have been better off. At least calling it an hypothesis, you'd be acknowledging that it is unproven and may be wrong.

It's no myth. Ifyou think you understand something but you cannot elucidate that understanding, then you are fooling yourself.

Well hi there, kettle, how's it going!? Want to apply your standard to yourself? Clearly, you believe that we - not to mention most of the scientific community - don't understand your idea. But if you understand it, then you should have no trouble explaining it to us, right? So do it! Don't keep evading. Or admit that you can't - you'll look less foolish that way.

By the way, I would agree with the sentiment except for the "grandma" part. The idea was meant to imply that you should be able to exlpain it in simple terms, for anyone to understand. But physics is difficult and not all people can understand it. It requires some knowledge/education.

I tell you what, I'll do all the details, so that you will take me seriously. Only once I've done that, I won't need you to take me seriously.

You've got yourself a deal! You've just acknowledged:

1. You haven't done all the details, therefore:
2. You shouldn't be taken seriously.
3. You present your ideas here because you know they are unworthy of being taken seriously.

We are very much in agreement!