The screw nature of electromagnetism

[CptBork]

Looking at his pictures, he doesn't even get the direction of the changing electric field correct in relation to the magnetic field. It's not even apparent from the diagram that he understands that the electric flux has to be changing in order to have magnetic curl. Argument by fingerpainting, how lame. 250 years ago Gauss at age 10 knew more stuff than Farsight does (i.e. calculus), how sad is that?

 

[PhysBang]

But you said the coordinate transform of E and B fields. They aren't fields, they're forces.

What is a field?

What is a force that has a value and/or vector at every location?

I'm guessing that Farsight still has me on ignore for asking him simple and direct questions.

 

[Farsight]

You're making a completely pointless distinction. In common parlance in physics, a "field" is just the attribution of any value or quantity to every point in space or space and time. The electric and magnetic fields attribute vector (and pseudovector) values to every point in space and time and are thus fields. Likewise, the local temperature and density of a block of matter, the local velocity of a fluid, and the population density and internal migration of residents of Great Britain are all (or could be described as) fields.

The distinction isn't pointless przyk. Instead it's absolutely crucial. In this article you can see Einstein referring to a field as "a state of space". Space has a particular state where an electron is, and "the" field Minkowski referred to is the electromagnetic field. So how do you depict it? Not with radial lines or concentric lines, but with something that communicates the greater whole.

The magnitude of an electromagnetic field at a given location is fully specified or 'measured' by six real numbers, which can be collected together into a single asymmetric tensor-valued field ($$F_{\mu\nu}$$), two vector-valued fields ($$\bar{E}$$ and $$\bar{B}$$), or just six real-valued fields ($$E_{x}$$, $$E_{y}$$, $$E_{z}$$, $$B_{x}$$, $$B_{y}$$, and $$B_{z}$$). These are different notations with different uses and advantages, but the information content in each case is exactly the same. They're different notations for exactly the same physics.

Fine. So draw tensor field Fμv. Find a way to depict it.

The electric and magnetic fields also aren't forces in the Newtonian sense of the word. They aren't the mass x acceleration of anything and they don't have the SI units of force. You can talk about the electric and magnetic forces on a charge (given by the respective terms in the Lorentz force law), but it's strictly a misnomer to call the electric and magnetic fields themselves "forces".

Tell that to Minkowski. I will reiterate that "the" field is the electromagnetic field and that electromagnetic field interactions between charged particles result in linear "electric" force and rotational "magnetic" force.

No you don't. In a vacuum (i.e. in the absence of electric charges and currents)...

...there is no electromagnetic field! An electromagnetic field "is a dual entity always having an electric and a magnetic component simultaneously created by their common sources: time-variable electric charges and currents". But let's press on:

...the two relevant Maxwell equations are

$$\begin{eqnarray}
\bar{\nabla} \,\times\, \bar{E} &=& -\, \frac{\partial \bar{B}}{\partial t} \,, \\
\bar{\nabla} \,\times\, \bar{B} &=& \frac{1}{c} \, \frac{\partial \bar{E}}{\partial t} \,.
\end{eqnarray}$$​

These relate the curl of the electric and magnetic fields, respectively, to the time-variance of the magnetic and electric fields.

There you go talking about fields again. Plural.

The first equation implies that if the magnetic field is changing in magnitude over time, then the electric field must have nonzero curl, and vice-versa. The second equation similarly implies that if the electric field is changing in magnitude over time (in the absence of electric currents)

Does not parse. Displacement current is a time-varying electric field.

then the magnetic field must have nonzero curl, and vice-versa.

Yes, but you are still exhibiting non-unified thinking. Let's say that you are small, that you are holding a test particle in your hand, and you are initially motional with respect to a nearby electron. Your test particle is subject to linear force only, and you say you are in an electric field. Then you move closer to the electron, but not directly at it, noting that the electric field is increasing in magnitude, and noticing that the test particle you are holding is also being subjected to rotational force as well as linear force. But you haven't changed or created any fields merely by moving. Because the electron has its electromagnetic field, as does your test particle.

Be aware this means it is perfectly possible for the electric field to be completely concentric, i.e. you can't simply recover the electric and magnetic fields as the "radial" and "concentric" parts of a combined field, as you seem to suggest in a diagram in your opening post, because an electric field need not always be radial.

The diagram depicts the electron's electromagnetic field. Like I said I could have combined radial electric lines with torus-like magnetic dipole lines, but that's perhaps a bit too confusing for the average reader and it takes us into Williamson / van der Mark territory.

 

[Farsight]

View attachment 7075

What is a field?

A state of space. The electron has its electromagnetic field. There aren't two states of space where that electron is.

What is a force that has a value and/or vector at every location?

The result of the interaction of two (or more) fields. If that electron is all on its lonesome, there ain't no force upon it. It takes two to tango.

I'm guessing that Farsight still has me on ignore for asking him simple and direct questions.

You're on ignore because you are abusive, and you do not contribute to the physics discussion. I peeked at this one.

 

[PhysBang]

A state of space. The electron has its electromagnetic field. There aren't two states of space where that electron is.

The result of the interaction of two (or more) fields. If that electron is all on its lonesome, there ain't no force upon it. It takes two to tango.

Do you know that your definition of field and forces are different from those used by practicing physicists? If your use of the terms is different, why should we adopt your use? Why should we re-interpret the words of physicists to your use rather than theirs?

You're on ignore because you are abusive, and you do not contribute to the physics discussion. I peeked at this one.

All I do is ask you to give us a demonstration of your theories using an actual physics example, even if only using a toy model. This is the core of physics.

If you feel that this is abuse, then you need to seek help.

 

[OnlyMe]

NOTE, I have not been following this thread.., and have not read through it in any depth... Someone may have already addressed the following. Farsight, may even have clarified himself, though I doubt it... I may have just failed to spend the time to dig it out of the remaining posts...

You're just playing the ignorant naysayer, lpetrich. It really does say space is twisted in the gravitomagnetism article, and electromagnetism really is like gravitomagnetism. Curved spacetime isn't curved space. But Percy Hammond does refer to curvature in The Role of the Potentials in Electromagnetism. He's co author of Geometry of Electromagnetic Systems. What curvature, what geometry? You're like the theologian here Loren. Actually, you're very much like a Young Earth Creationist. I show you the evidence, and you say nay nay nay.

I did check the only earlier link/reference to a gravitomagnetism, I could find in your earlier post. It referenced the GP-B experiment...

I found no reference in that article, nor do I remember any reference in any of the publicly available documentation of the GP-B experiment where there was any reference to space being twisted. There is reference, used as analogy.., to spacetime being twisted.

Even though neither is defined in a manner that is completely satisfying, there is a big difference between the definition of space and spacetime! One of the most significant being that spacetime, through its association with relativity, implies a dynamic component, where space alone does not. Any twisting, as analogy explaining experimental results or in some real context, is a dynamic characteristic.

Perhaps you should provide a clear and complete definition of what you mean when you use the word space, that includes some dynamic characteristic.

Aside from that, on the surface it appears to me, that your statement quoted in bold above.., is false.

 

[przyk]

The distinction isn't pointless przyk. Instead it's absolutely crucial. In this article you can see Einstein referring to a field as "a state of space". Space has a particular state where an electron is, and "the" field Minkowski referred to is the electromagnetic field.

This doesn't address anything I said. Speaking of "the electric field", "the magnetic field", and "the electromagnetic field" are not mutually contradictory. All are consistent with how the technical term "field" is commonly used in physics. You can hardly claim the vast majority of physicists misunderstand electromagnetism just because they use standard terminology correctly.

Fine. So draw tensor field Fμv. Find a way to depict it.

Why are you presuming there even is a simple and useful way to depict it? An idea doesn't have to come in the form of a pretty picture to be useful or worthwhile. There's no standard diagram for the Faraday tensor because easy visualisation isn't and never was the point of introducing it into electromagnetism.

Tell that to Minkowski.

How? He died more than a hundred years ago.

The diagram depicts the electron's electromagnetic field. Like I said I could have combined radial electric lines with torus-like magnetic dipole lines, but that's perhaps a bit too confusing for the average reader

I think you routinely seriously underestimate average readers.

You seem to have some bizarre idea that electromagnetism is an advanced and arcane topic that only a few geniuses understand well. It isn't. Much of modern technology is dependent electromagnetism, and it only works because many engineers (never mind the physicists) understand it perfectly well. In fact, just to put this into perspective: at my local university, the business students learn some basic electromagnetism as part of a general physics course in their first year, including the integral forms of Maxwell's equations, and they're expected to understand what they learn well enough to solve simple problems with it.

 

[lpetrich]

In this article you can see Einstein referring to a field as "a state of space".

So like a theologian. Treating Einstein as a prophet of revealed truth.

Space has a particular state where an electron is, and "the" field Minkowski referred to is the electromagnetic field.

More theologian-like argument. Treating Minkowski likewise.

So how do you depict it? Not with radial lines or concentric lines, but with something that communicates the greater whole.

Why is it necessary to draw pictures of it?

Fine. So draw tensor field Fμv. Find a way to depict it.

Again, why is it necessary to draw pictures of it?

Tell that to Minkowski. I will reiterate that "the" field is the electromagnetic field and that electromagnetic field interactions between charged particles result in linear "electric" force and rotational "magnetic" force.

I can't speak for him, but he would have said that electric and magnetic fields are parts of of the electromagnetic tensor. That is evident from The Fundamental Equations for Electromagnetic Processes in Moving Bodies - Wikisource, the free online library at Hermann Minkowski - Wikisource, the free online library Also there is Space and Time (Prasad) - Wikisource, the free online library about space-time unification.

 

[Farsight]

... I found no reference in that article, nor do I remember any reference in any of the publicly available documentation of the GP-B experiment where there was any reference to space being twisted...

You didn't look too hard:

 

[Farsight]

This doesn't address anything I said. Speaking of "the electric field", "the magnetic field", and "the electromagnetic field" are not mutually contradictory. All are consistent with how the technical term "field" is commonly used in physics. You can hardly claim the vast majority of physicists misunderstand electromagnetism just because they use standard terminology correctly.

I guess I do, pryzk. I guess that's the size of it. The vast majority of physicists have a cargo-cult misunderstanding of electromagnetism that conflates field with force as if unification never happened.

Why are you presuming there even is a simple and useful way to depict it? An idea doesn't have to come in the form of a pretty picture to be useful or worthwhile. There's no standard diagram for the Faraday tensor because easy visualisation isn't and never was the point of introducing it into electromagnetism.

Because it's a state of space, and you've heard of bispinor and frame-dragging. How hard can it be?

How? He died more than a hundred years ago.

Before his time. If he hadn't died, where would we be? He understood the screw nature of electromagnetism, that we had one field and two forces. Maybe given time he would have understood space and motion as opposed to space and time. But that's one for another day.

I think you routinely seriously underestimate average readers.

Maybe. But so far you seem to be one of few readers who have offered a sensible sincere response. Some other readers merely whine or spit feathers of outrage at the very thought that somebody knows more than they do.

You seem to have some bizarre idea that electromagnetism is an advanced and arcane topic that only a few geniuses understand well. It isn't. Much of modern technology is dependent [ON] electromagnetism, and it only works because many engineers (never mind the physicists) understand it perfectly well. In fact, just to put this into perspective: at my local university, the business students learn some basic electromagnetism as part of a general physics course in their first year, including the integral forms of Maxwell's equations, and they're expected to understand what they learn well enough to solve simple problems with it.

I don't think electromagnetism is some advanced arcane topic that only a few geniuses understand well. Instead I think it's badly misunderstood by most physicists. In post #3 you can see me referring to Geometry of Electromagnetic Systems (Monographs in Electrical and Electronic Engineering and saying What geometry? What curvature? The physicists don't know, and it would seem, don't want to admit it.

 

[PhysBang]

I guess I do, pryzk. I guess that's the size of it. The vast majority of physicists have a cargo-cult misunderstanding of electromagnetism that conflates field with force as if unification never happened.

So you admit that when physicists use these terms, they do not mean what you say they mean?

So why should we accept your cherry-picked quotations that you now admit do not mean what you say they mean?

Before his time. If he hadn't died, where would we be? He understood the screw nature of electromagnetism, that we had one field and two forces.

You mean a tensor field like to one described above?

 

[Russ_Watters]

Farsight, you're back to the 'everyone else in the world is crazy idiots, but me' crazy paranoia. That isnt going to help you convince anyone of anything you want to convince them of. So before you go any further off Crackpot Cliff, maybe you should try actually describing what your pinwheel diagram shows. What numbers/vectors/concepts are represented on the curves of the pinwheel?

Also, could you put a point on all of this: what actual problem in physics does your graph solve? Ie, what are scientists/engineers doing that isn't working that using your diagram would fix?

 

[OnlyMe]

You didn't look too hard:

OK I missed that, but your reference was out of context and the error was corrected in the next sentence, as emphasized in bold below.

But if space is twisted, the direction of the gyroscope's axis should drift over time. By noting this change in direction relative to the star, the twists of space-time could be measured.

And then again later in the same article...

... the frame dragging effect is the amount of wobble caused by the spin of the Earth (the twist in spacetime)....

You see those kinds of errors often in lay oriented articles and press releases. Not so often in the scientific papers and reports.

Farsight, I don't always agree with the accepted definition and interpretation of spacetime, but before you go claiming that space itself can be twisted, warped or curved, come up with a dynamic definition, that allows for it.

 

[przyk]

I guess I do, pryzk. I guess that's the size of it. The vast majority of physicists have a cargo-cult misunderstanding of electromagnetism that conflates field with force as if unification never happened.

But you don't have any evidence for that. First off you would need to survey and understand what the vast majority of physicists actually think about electromagnetism before you could establish they were wrong, otherwise you'd inevitably just waste a lot of effort refuting the wrong things. I don't see any evidence you've done even that. You just seem generally disinterested in what the majority of physicists think about physics, and from my experience knowing physicists (working at a large, highly international, research-oriented university) and of course my own views, it's very often not what you say it is.

Because it's a state of space

You don't have any evidence for that either. Even if Maxwell or Heaviside or Minkowski or some other famous historical physicist tried to promote such an idea, that alone doesn't establish it's a good idea. A perfectly normal part of the advancement of physics is that ideas that aren't useful eventually get discarded, and famous physicists aren't exempt from that. So if Maxwell or others said said certain things that didn't work their way into modern textbooks, why should I believe they were omitted for any reason other than that they didn't pan out?

He understood the screw nature of electromagnetism

Speaking of that, what is that even supposed to mean? On the face of it, saying the electromagnetic field has "screw nature" isn't usefully precise. It's such a vague statement it could mean just about anything.

In post #3 you can see me referring to Geometry of Electromagnetic Systems (Monographs in Electrical and Electronic Engineering and saying What geometry? What curvature? The physicists don't know, and it would seem, don't want to admit it.

Your post #3 links to an article discussing the electromagnetic potential vector. The reference to curvature comes from the fact that quantum electrodynamics and general relativity are both what we would nowadays call "gauge field" theories. Without going into details, the Faraday tensor ($$F_{\mu\nu}$$) plays an analogous role in QED (it measures the presence of a nontrivial electromagnetic potential) as the Riemann curvature tensor does in general relativity (it measures the presence of a nontrivial spacetime geometry). Emphasis on analogous: QED is not a theory about the electromagnetic field actually being curved space.

This is, by the way, routinely taught in university physics courses, and most physics graduates who studied both general relativity and QED or the Standard Model should be familiar with the similarity between them as gauge field theories.

 

[exchemist]

But you don't have any evidence for that. First off you would need to survey and understand what the vast majority of physicists actually think about electromagnetism before you could establish they were wrong, otherwise you'd inevitably just waste a lot of effort refuting the wrong things. I don't see any evidence you've done even that. You just seem generally disinterested in what the majority of physicists think about physics, and from my experience knowing physicists (working at a large, highly international, research-oriented university) and of course my own views, it's very often not what you say it is.




You don't have any evidence for that either. Even if Maxwell or Heaviside or Minkowski or some other famous historical physicist tried to promote such an idea, that alone doesn't establish it's a good idea. A perfectly normal part of the advancement of physics is that ideas that aren't useful eventually get discarded, and famous physicists aren't exempt from that. So if Maxwell or others said said certain things that didn't work their way into modern textbooks, why should I believe they were omitted for any reason other than that they didn't pan out?




Speaking of that, what is that even supposed to mean? On the face of it, saying the electromagnetic field has "screw nature" isn't usefully precise. It's such a vague statement it could mean just about anything.




Your post #3 links to an article discussing the electromagnetic potential vector. The reference to curvature comes from the fact that quantum electrodynamics and general relativity are both what we would nowadays call "gauge field" theories. Without going into details, the Faraday tensor ($$F_{\mu\nu}$$) plays an analogous role in QED (it measures the presence of a nontrivial electromagnetic potential) as the Riemann curvature tensor does in general relativity (it measures the presence of a nontrivial spacetime geometry). Emphasis on analogous: QED is not a theory about the electromagnetic field actually being curved space.

This is, by the way, routinely taught in university physics courses, and most physics graduates who studied both general relativity and QED or the Standard Model should be familiar with the similarity between them as gauge field theories.

Farsight does not seem to have studied university level physics, which may be the problem. On another forum he revealed - before being banned - that he is in fact someone called John Duffield, whose profile appears here: http://www.science20.com/profile/john_duffield

He has self-published a book on Relativity, 2nd hand copies of which may be had on Amazon for £4 or so.

 

[Farsight]

The guys know all that, exchemist.

But you don't have any evidence for that. First off you would need to survey and understand what the vast majority of physicists actually think about electromagnetism before you could establish they were wrong, otherwise you'd inevitably just waste a lot of effort refuting the wrong things. I don't see any evidence you've done even that. You just seem generally disinterested in what the majority of physicists think about physics, and from my experience knowing physicists (working at a large, highly international, research-oriented university) and of course my own views, it's very often not what you say it is.

OK. I don't have any conclusive evidence of what all physicists think about electromagnetism. But I have some evidence of what some physicists think about electromagnetism.

You don't have any evidence for that either. Even if Maxwell or Heaviside or Minkowski or some other famous historical physicist tried to promote such an idea, that alone doesn't establish it's a good idea. A perfectly normal part of the advancement of physics is that ideas that aren't useful eventually get discarded, and famous physicists aren't exempt from that. So if Maxwell or others said said certain things that didn't work their way into modern textbooks, why should I believe they were omitted for any reason other than that they didn't pan out?

Come on przyk, what do you think an electromagnetic field is? A matrix? Something abstract? Something you can take out of space? Or a state of space, like Einstein said?

Speaking of that, what is that even supposed to mean? On the face of it, saying the electromagnetic field has "screw nature" isn't usefully precise. It's such a vague statement it could mean just about anything.

He understood that there was one field and two forces. Not two fields.

Your post #3 links to an article discussing the electromagnetic potential vector. The reference to curvature comes from the fact that quantum electrodynamics and general relativity are both what we would nowadays call "gauge field" theories. Without going into details, the Faraday tensor () plays an analogous role in QED (it measures the presence of a nontrivial electromagnetic potential) as the Riemann curvature tensor does in general relativity (it measures the presence of a nontrivial spacetime geometry). Emphasis on analogous: QED is not a theory about the electromagnetic field actually being curved space.

QED isn't. But Percy Hammond isn't talking about QED. And whatever the theory is, space has a certain state in the place where we say the field is. So come on: What geometry? What curvature?

This is, by the way, routinely taught in university physics courses, and most physics graduates who studied both general relativity and QED or the Standard Model should be familiar with the similarity between them as gauge field theories.

That seems to take us back to your original point.

 

[brucep]

Farsight does not seem to have studied university level physics, which may be the problem. On another forum he revealed - before being banned - that he is in fact someone called John Duffield, whose profile appears here: http://www.science20.com/profile/john_duffield

He has self-published a book on Relativity, 2nd hand copies of which may be had on Amazon for £4 or so.

For somebody with a 'life long' interest in physics he's managed not to learn any over the interval 'life long'.

 

[origin]

He has self-published a book on Relativity, 2nd hand copies of which may be had on Amazon for £4 or so.

Not to get to graphic but a better use of the £4 would be to use it a toilet paper.

 

[Farsight]

Farsight, you're back to the 'everyone else in the world is crazy idiots, but me' crazy paranoia.

Not me mate. I've just read the original material, it doesn't square with the popscience you read, so I've told you about it and now we're discussing it. Don't try telling me I must be wrong because I'm outvoted. Science is not a democracy. Evidence rules.

That isnt going to help you convince anyone of anything you want to convince them of. So before you go any further off Crackpot Cliff, maybe you should try actually describing what your pinwheel diagram shows. What numbers/vectors/concepts are represented on the curves of the pinwheel?

I made that clear in the OP. Didn't you read it? Did you just look at the pictures? It depicts the electromagnetic field, which features frame-dragged space. Space is curved, or curled if you prefer. Or twisted. Oh and spare me the crackpot cliff you ignorant naysayer.

Also, could you put a point on all of this: what actual problem in physics does your graph solve? Ie, what are scientists/engineers doing that isn't working that using your diagram would fix?

Unification of electromagnetism and gravity and spinoff technology.

 

[Farsight]

Not to get to graphic but a better use of the £4 would be to use it a toilet paper.

Hey, some copies are priced at as much as £49. Collectors item!

See Amazon.