Merged Relativity+ / Farsight

[steenkh]

Geddoutofit, ben m said the electron is a point-particle. You can't diffract a point-particle. Asking for me to point out an error in an equation is specious, and you know it.

Is this a semantic analysis of ben m's statements? The wave-particle duality has been well established in conventional physics for a long time. If you think that conventional physics cannot handle diffractions, you will have to show it, not merely claim it. This is not a specious demand; it is time for you to put your cards on the table and prove that you have the winning hand.

On this forum you give a strong impression that you are bluffing: when you are asked to show the errors of conventional physics, or make predictions about your own physics, you resort to dismissal ("Bah!"), graphs, or claims that Einstein is on your side. You never actually produce the equations. What would you yourself think if your opponents used these kinds of evasion all the time?

 

[Farsight]

Is this a semantic analysis of ben m's statements? The wave-particle duality has been well established in conventional physics for a long time. If you think that conventional physics cannot handle diffractions, you will have to show it, not merely claim it. This is not a specious demand; it is time for you to put your cards on the table and prove that you have the winning hand.

I've done it already. I've shown the evidence for the wave nature of the electron. It is overwhelming. And yet ben m tried to dismiss it as "evidence".

On this forum you give a strong impression that you are bluffing: when you are asked to show the errors of conventional physics, or make predictions about your own physics, you resort to dismissal ("Bah!"), graphs, or claims that Einstein is on your side. You never actually produce the equations. What would you yourself think if your opponents used these kinds of evasion all the time?

Bah. More specious fluff. Let's have a look at diffraction on Wikipedia. It says "Diffraction refers to various phenomena which occur when a wave encounters an obstacle or a slit". Nothing wrong with that. And since you can diffract an electron, it's a wave. There are no equations that change that. If I said black isn't white what would you do? Duck and dive, then try to make out I'm bluffing and ask me for an equation? As if that's going to save you.

 

[W.D.Clinger]

Don't blame me for the confusion between force and field.

If we don't blame you for the confusion you have repeatedly expressed in your own posts, then whom should we blame?

This started when you wrote:

I'm sorry edd, but this doesn't parse. It isn't a vector, it's the electromagnetic field, it isn't new, E and B are the forces that result from field interactions, and I've been trying to explain it.

edd corrected you:

E and B are not forces, they are fields.

Instead of accepting that mild correction, you responded with this non-sequitur:

Look at the Minkowski quote.

To which edd replied:

When Minkowski spoke of the electric and magnetic forces, he meant that in the sense that someone might say 'there are four fundamental forces'. When you refer to E and B you are referring to specific more precisely defined quantities that allow you to calculate the force (as in mass times acceleration) on a charged particle.

When you said

It isn't a vector, it's the electromagnetic field, it isn't new, E and B are the forces that result from field interactions

that's just flat wrong. By definition E and B are the fields, not 'the forces that result from field interactions'.

edd is right, and Farsight wrong.

The confusion is Farsight's, and Farsight's alone.

Believing the E and B fields to be forces is a typical mistake made by people who hope to understand electromagnetism without coming to grips with the mathematics of Maxwell's equations. No one should be surprised that Farsight made this mistake and, when corrected, continued to insist he was right.

When Farsight says he understands electromagnetism better than the physicists, he is (as steenkh observed) bluffing. When his bluff is called, he bluffs more loudly:

If I said black isn't white what would you do? Duck and dive, then try to make out I'm bluffing and ask me for an equation? As if that's going to save you.

 

[Farsight]

I'm not confused at all. But you are utterly unconvincing. Again see Minkowski’s Space and Time:

"In the description of the field caused by the electron itself, then it will appear that the division of the field into electric and magnetic forces is a relative one with respect to the time-axis assumed; the two forces considered together can most vividly be described by a certain analogy to the force-screw in mechanics; the analogy is, however, imperfect."

It's the field. The electromagnetic field. It results in electric and magnetic forces. Edd is not right. When Minkowski spoke of the electric and magnetic forces, he did not mean it in the sense that someone might say 'there are four fundamental forces'.

...Believing the E and B fields to be forces...

Let's have a little look at electromagnetic field on good old Wikipedia. What does it say? Let's see now:

"In the past, electrically charged objects were thought to produce two different, unrelated types of field associated with their charge property. An electric field is produced when the charge is stationary with respect to an observer measuring the properties of the charge, and a magnetic field (as well as an electric field) is produced when the charge moves (creating an electric current) with respect to this observer. Over time, it was realized that the electric and magnetic fields are better thought of as two parts of a greater whole — the electromagnetic field."

Did you get that Clinger? The electric and magnetic fields are better thought of as two parts of a greater whole — the electromagnetic field. Looks like you're stuck in the past mate. About a hundred and fifty years in the past.

 

[steenkh]

I've done it already. I've shown the evidence for the wave nature of the electron. It is overwhelming. And yet ben m tried to dismiss it as "evidence".

I am sure you have shown the evidence for the wave nature of the electron, but I do not see you show that electrons are not also point-like. The relevant Wikipedia article is this one: Wave-particle duality. What is wrong with that?

Bah. More specious fluff. Let's have a look at diffraction on Wikipedia. It says "Diffraction refers to various phenomena which occur when a wave encounters an obstacle or a slit". Nothing wrong with that. And since you can diffract an electron, it's a wave. There are no equations that change that. If I said black isn't white what would you do? Duck and dive, then try to make out I'm bluffing and ask me for an equation? As if that's going to save you.

Evasion noted. You reacted but you did actually not respond to what I said.

 

[W.D.Clinger]

I'm not confused at all.

Bare assertion, contradicted by abundant evidence.

It's the field. The electromagnetic field. It results in electric and magnetic forces.

The electromagnetic field F_μν is a tensor field. The electric field E and the magnetic field B are vector fields. E and B are not forces.

(Farsight has a long history of saying the electric and magnetic fields aren't even fields, even though his quote-mined sources are chock-full of references to the electric and magnetic fields. As we now know, Farsight's personal and highly idiosyncratic definition of a field is quite different from what physicists mean by the word. When he quotes Wikipedia, for example, he skips right over Wikipedia's own references to the electric and magnetic fields. Farsight has a bad habit of not reading his own quotations.)​

In Minkowski space with the Minkowski metric, the relationship between the electromagnetic tensor field F_μν and the electric and magnetic vector fields E and B is expressed by these equations:

• F₀₁ = E_x
• F₀₂ = E_y
• F₀₃ = E_z
• F₃₂ = B_x
• F₁₃ = B_y
• F₂₁ = B_z

The other ten components of F_μν are determined by those six and by the antisymmetry F_μν = - F_νμ.

The chief advantage of using the electromagnetic tensor field F_μν instead of the separate vector fields E and B is that the vector fields depend upon the coordinate system you choose to use. Although the components of the tensor field depend upon the coordinate system, the tensor itself (considered as a higher-order geometric object) does not.

(Farsight, of course, has no idea of what that means. It is, after all, mathematics.)

(Farsight also has a long and undistinguished history of denying the admissibility of coordinate transformations (e.g. between Schwarzschild, Lemaître, Eddington-Finkelstein, Painlevé-Gullstrand, and Kruskal-Szekeres coordinates), so the chief advantage of using the electromagnetic tensor field F_μν instead of the separate vector fields E and B is wasted on Farsight.)​

For most everyday applications of electromagnetism, the standard decomposition of Minkowski spacetime into Euclidean space and time is adequate. For those applications, engineers and scientists generally use the familiar vector forms of Maxwell's equations instead of the tensor formulations. Both formulations give exactly the same results, so it's a matter of convenience and personal choice.

Only a crackpot would argue otherwise.

It's the field. The electromagnetic field. It results in electric and magnetic forces.

The electric and magnetic fields also result in electric and magnetic forces. After all, the E and B vector fields are just another way of writing the F_μν tensor field. That's a consequence of the unification of electric and magnetic fields into a single electromagnetic field.

Edd is not right.

Wrong.

When Minkowski spoke of the electric and magnetic forces, he did not mean it in the sense that someone might say 'there are four fundamental forces'.

He was talking about the forces that result from the electric and magnetic fields. To distinguish between electric and magnetic forces, as Minkowski did, you must first divide the electromagnetic field into electric and magnetic fields. Minkowski's statement therefore refutes any crackpot who would deny the legitimacy of separating the electromagnetic field into electric and magnetic fields E and B.

Did you get that Clinger? The electric and magnetic fields are better thought of as two parts of a greater whole — the electromagnetic field. Looks like you're stuck in the past mate. About a hundred and fifty years in the past.

My third edition of Jackson's Classical Electrodynamics was published in 1999. It contains hundreds (probably thousands) of equations that mention E and/or B. It also contains dozens (probably hundreds) of equations that mention the electromagnetic tensor field F_μν.

The modern view recognizes the importance of unifying the electric and magnetic vector fields into an electromagnetic tensor field, but does not deny the legitimacy or usefulness of the vector fields E and B, nor does the modern view deny that E and B are vector fields. Only a crackpot would do that.

 

[Ziggurat]

Yes. You google on magnetic lines of force, and up come images of magnetic field lines. Don't blame me for the confusion between force and field.

I will blame you for confusion that you perpetuate.

Aaargh! The confusion is too bad with electric field because the field is the electromagnetic field. Two particles, each with an electromagnetic field, if they have no initial relative motion, move towards one another linearly, or away from one another linearly. Two electrons behave exactly like two positrons, which is why I omitted the arrowheads on my depiction, unlike this typical depiction:

You're still wrong. First off, if you want to talk about the full electromagnetic field as a single entity, it's a 4-dimensional rank-2 antisymmetric tensor, so you can't draw it with lines on paper anyways. Second, since you're insistent on talking about the full electromagnetic field, your claim that motion will be completely radial is also wrong. If the two particles have magnetic dipole moments, then not only the magnitudes but even the direction of force between them depends on the orientation of those dipole moments, and need not be completely radial. You can see that from this equation:
http://upload.wikimedia.org/math/8/d/c/8dc26e5c5b147a3d9735b73092db7e2f.png

Sigh. I suppose somebody will now tell us that when a charged particle moves through an electric field, it creates a magnetic field.

FTFY.

Or, if you want to talk in the language of relativity, when you Lorentz transform an electromagnetic field tensor with only electric field components, you get a tensor with both electric and magnetic field components.

Did you get that Clinger? The electric and magnetic fields are better thought of as two parts of a greater whole — the electromagnetic field. Looks like you're stuck in the past mate. About a hundred and fifty years in the past.

Yes, Farsight, the electric and magnetic fields are really components of a 4-dimensional symmetric rank-2 tensor, and I'm sure W.D. knows that.

But you can't just add different components of a tensor together and expect to get a meaningful result. But that's what you've tried to do, and it makes not one lick of sense.

 

[DeiRenDopa]

I'm not confused at all.

<snip>

Odd, then, that despite many years of trying, in many different forums, you have failed to 'unconfuse' anyone else (Senex doesn't count; he's from Marketing, a.k.a. the Department of Creative Lying ).

Given this unambiguous track record of complete failure, don't you think it might be a good idea to try something different? For example, learn enough of the mathematics used by Maxwell, Einstein, etc to be able explain your 'unconfusion' using the same (mathematical) tools and techniques they used?

 

[Farsight]

First off, if you want to talk about the full electromagnetic field as a single entity, it's a 4-dimensional rank-2 antisymmetric tensor

Whoa! Stop right there. See Einstein talking about field theory in 1929. See Expanding the theory where Einstein is talking about electromagnetic and gravitational fields. Note this:

"The two types of field are causally linked in this theory, but still not fused to an identity. It can, however, scarcely be imagined that empty space has conditions or states of two essentially different kinds, and it is natural to suspect that this only appears to be so because the structure of the physical continuum is not completely described by the Riemannian metric".

Einstein thought of a field as "a state of space". I'm with Einstein on that. Now, what's a tensor? It's a "geometric object". A mathematical object. See where the wiki article says "For example, a linear map can be represented by a matrix, a 2-dimensional array, and therefore is a 2nd-order tensor". A tensor is a matrix. The electromagnetic field is described by a tensor, but that's not what it is. The map is not the territory. What it is, is a state of space.

so you can't draw it with lines on paper anyways.

The drawing isn't ideal. Curl is more than curvature on a flat plane. The lines should be curve towards/away from you as well. But you still can depict the electromagnetic field just as you can depict the gravitational field and the gravitomagnetic field.

Second, since you're insistent on talking about the full electromagnetic field, your claim that motion will be completely radial is also wrong. If the two particles have magnetic dipole moments, then not only the magnitudes but even the direction of force between them depends on the orientation of those dipole moments, and need not be completely radial. You can see that from this equation: http://upload.wikimedia.org/math/8/d/c/8dc26e5c5b147a3d9735b73092db7e2f.png

No problem. That's a detail I didn't go into. But note that pictures of charged particles with radial electric field lines is in plenty of textbooks.

FTFY.

I said I suppose somebody will now tell us that when a charged particle moves through an electric field, it creates a magnetic field. And you "fixed that for me" by saying I suppose somebody will now tell us that when a charged particle moves through an electric field, it creates a magnetic field. You didn't fix it. You forgot your relativity. You don't create a magnetic field by moving a charged particle. Just as you don't create a magnetic field by moving past a charged particle. Because that particle has its electromagnetic field. You just see a different aspect of the greater whole.

Or, if you want to talk in the language of relativity, when you Lorentz transform an electromagnetic field tensor with only electric field components, you get a tensor with both electric and magnetic field components.

See above. Just move through the space around a charged particle. You don't change that space merely by moving.

Yes, Farsight, the electric and magnetic fields are really components of a 4-dimensional symmetric rank-2 tensor, and I'm sure W.D. knows that. But you can't just add different components of a tensor together and expect to get a meaningful result. But that's what you've tried to do, and it makes not one lick of sense.

It makes no sense to you because you think the field is the mathematical object rather than a state of space.

 

[Farsight]

The electromagnetic field F_μν is a tensor field. The electric field E and the magnetic field B are vector fields. E and B are not forces.

Sigh. Let's look that up shall we:

"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."

(Farsight has a long history of saying the electric and magnetic fields aren't even fields, even though his quote-mined sources are chock-full of references to the electric and magnetic fields. As we now know, Farsight's personal and highly idiosyncratic definition of a field is quite different from what physicists mean by the word. When he quotes Wikipedia, for example, he skips right over Wikipedia's own references to the electric and magnetic fields. Farsight has a bad habit of not reading his own quotations.)​

Cringe! The excerpt I gave above is from the Wikipedia electric field article! The electric field describes the force on a charged particle. It doesn't describe the state of space around a charged particle.

In Minkowski space with the Minkowski metric, the relationship between the electromagnetic tensor field F_μν and the electric and magnetic vector fields E and B is expressed by...

Yeah yeah. And like I said to Zig, the tensor describes the field, and the map is not the territory.

Only a crackpot would argue otherwise.

Can we have some moderation here?

The electric and magnetic fields also result in electric and magnetic forces...

See above, the electric field vector field describes the force on a charged particle.

He was talking about the forces that result from the electric and magnetic fields. To distinguish between electric and magnetic forces, as Minkowski did, you must first divide the electromagnetic field into electric and magnetic fields.

Only Minkowski said forces. Here we go:

"In the description of the field caused by the electron itself, then it will appear that the division of the field into electric and magnetic forces..."

Minkowski's statement therefore refutes any crackpot who would deny the legitimacy of separating the electromagnetic field into electric and magnetic fields E and B.

He said forces, so I'm not some crackpot, now am I?

My third edition of Jackson's Classical Electrodynamics was published in 1999. It contains hundreds (probably thousands) of equations that mention E and/or B. It also contains dozens (probably hundreds) of equations that mention the electromagnetic tensor field F_μν.

And it also says one should properly speak of the electromagnetic field Fuv rather than E or B separately. Doesn't it Clinger?

The modern view recognizes the importance of unifying the electric and magnetic vector fields into an electromagnetic tensor field, but does not deny the legitimacy or usefulness of the vector fields E and B, nor does the modern view deny that E and B are vector fields. Only a crackpot would do that.

And again:

"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."

 

[edd]

per unit charge

 

[ben m]

I've done it already. I've shown the evidence for the wave nature of the electron. It is overwhelming. And yet ben m tried to dismiss it as "evidence".

It's like: imagine you (mistakenly) believed all mammals are terrestrial.
Me: "But the whale, for example, is aquatic,"
You: "Get off it. I've shown TONs of evidence that the whale is a mammal---lungs, mammary glands for crying out loud."
Me: "That is evidence that the whale is a mammal. The whale is both a mammal and aquatic. Do you have any evidence that the whale is not aquatic?"
You: "Stop ignoring the evidence. You're denying that the whale has mammary glands?"


You have shown evidence for the wave nature of the electron.

You have not shown evidence against the particle nature of the electron.

The electron is both a wave and a particle. Diffraction (and coherent interactions generally) often involve the wave nature. Scattering (and incoherent interactions generally) often involve the particle nature.

You didn't have a problem with this for atoms, remember? You admitted easily that (a) a hydrogen atom can diffract, with a wave nature extending as far as you like, and also (b) a hydrogen atom has an particle-like radius which experiments find to be 0.5 angstroms.

Same thing for an electron. (a) an electron can diffract, with a wave nature extending as far as you like, and also (b) an electron has an particle-like radius which experiments find to be much, much smaller than 0.5 angstroms, smaller than 1pm, smaller than 1fm, in fact it looks pointlike.

 

[Ziggurat]

The map is not the territory.

That's an awfully small nit to pick, especially since you couldn't actually tie that nit to any logical mistakes that followed from it.

And you're wrong anyways. The matrix representation of a tensor is the map, the tensor itself is the territory.

The drawing isn't ideal.

It's more than "not ideal". It's flat-out wrong.

No problem. That's a detail I didn't go into. But note that pictures of charged particles with radial electric field lines is in plenty of textbooks.

Hey, you're the one who insisted that we deal with electromagnetic fields as single, unified thing, and not simply as separate electric and magnetic fields. It's a bit rich to now appeal to textbooks when those textbooks treat them separately.

I said I suppose somebody will now tell us that when a charged particle moves through an electric field, it creates a magnetic field. And you "fixed that for me" by saying I suppose somebody will now tell us that when a charged particle moves through an electric field, it creates a magnetic field. You didn't fix it. You forgot your relativity. You don't create a magnetic field by moving a charged particle.

Yes, actually, you do.

Just as you don't create a magnetic field by moving past a charged particle. Because that particle has its electromagnetic field. You just see a different aspect of the greater whole.

Wihin a given reference frame, either there is a magnetic field, or there is not. When you specify motion, you are specifying the reference frame. The fact that there's a magnetic field in reference frame A does not mean that there is a magnetic field in reference frame B. Yes, these are all part of the electromagnetic field tensor, but the components of the tensor are not arbitrary, and they DO change when you change reference frames.

It makes no sense to you because you think the field is the mathematical object rather than a state of space.

The math is a description of the field. But the field itself, the actual physical field, is a tensor, because it has all the properties of a tensor.

What you have done by adding the magnetic and electric fields together is analogous to adding the sides of a rectangle together and declaring that you've calculated the length of the diagonal. Well, you haven't.

 

[Farsight]

per unit charge

We all know that, edd.

 

[ctamblyn]

We all know that, edd.

Knowing the E and B fields at a point in space at a particular time allows you to compute the force a charged particle would experience if it moved through that point at that time, but neither E nor B is equal to that force. Except in special circumstances, the force is not even proportional to either E or B separately. The force F the charged particle would experience, as you ought to know, is given by the Lorentz force law:

F = qE + qv×B,
​

with v the velocity and q the charge. Of course, if no particle is at that point then it makes no sense to speak of a force at that point either, but we can still speak of E and B there.

 

[ben m]

The electromagnetic field. A field is a state of space. It's twisted. To say how twisted you need to give the degree of twist and the direction.

This sounds like the sort of sentence that ought to precede a description of how to define the "direction" and "degree of twist" of a state of space.

In this sense it's a vector field

... and indeed it sounds like Farsight is about to tell us which vector field is twisted ...

but it's not the vector field you're used to that gives the strength and direction of some force. If you have two identical electromagnetic fields around two dynamical spinors with no initial relative motion, the force between them is linear and it pushes them apart.

.. but actually he only knows what vector fields are NOT twisted. (And possibly only because we told him so.)

If you don't know what vector you are talking about, how are you so certain it's twisted? How can you pretend make clear statements about the curl of a vector field you can't name, can't plot, and can't describe, and therefore whose curl you've obviously never evaluated? If an actual scientist did this in a paper, it'd be called "scientific fraud". I don't say that idly: Jan Henrik Schön's fraud investigation criticized him for publishing plots that he originally presented as data but later admitted were illustrative cartoons.

I repeat my diagnosis. Farsight has a vague mental picture of some twisted lines around a point. Now, of course, he's struggling to find something about electromagnetism he can cite that justifies his spirally drawing.

It's like if a kid draws a picture of an animal---six legs, wings, tentacles, breathes fire---and tells you it's his favorite animal, he knows all the facts about it, and if you haven't heard of it it's because you're dumb. But also that he doesn't know what it's called, it's unfair to ask, he's still trying to find it in the encyclopedia, which is also dumb.

 

[lpetrich]

Senex: the problem is that professional physicists or cosmologists think they know it all, when they don't. They are so convinced of this that they dismiss Einstein and the evidence, and Maxwell and Minkowski, and anything else that doesn't fit with what they know. And woe betide anybody who attempts to tell them something they don't know. It isn't me who is resistant to learning. It's ben m et al.

Nobody's dismissing the claimed evidence, and your invoking of Einstein and Maxwell and Minkowski seems so much like a theologian -- invoking some sacred book that one believes to contain revealed truth.

Science doesn't work that way. About Maxwell and Einstein and Minkowski and the like, we have no trouble pointing out that they had made mistakes when we conclude that they have. We don't consider their writings revealed truth.

 

[Perpetual Student]

Knowing the E and B fields at a point in space at a particular time allows you to compute the force a charged particle would experience if it moved through that point at that time, but neither E nor B is equal to that force. Except in special circumstances, the force is not even proportional to either E or B separately. The force F the charged particle would experience, as you ought to know, is given by the Lorentz force law:

F = qE + qv×B,
​

with v the velocity and q the charge. Of course, if no particle is at that point then it makes no sense to speak of a force at that point either, but we can still speak of E and B there.

Pay attention to the above post, Farsight; you might learn something.
Also:

A field is a physical quantity that has a value for each point in space and time.

and: LINK

A field can be classified as a scalar field, a vector field, a spinor field or a tensor field according to whether the value of the field at each point is a scalar, a vector, a spinor or a tensor, respectively

So, clearly it's a matter of perspective. B fields and E fields are physical quantities that (have) a value for each point in space and time. They are by definition (vector) fields. The unification of these two vector fields into a single electromagnetic (tensor) field is known to all who have studied physics, but that does not prohibit, delegitimize or impoversh the treatment of either E or B as separate fields.
Take, for example two static electric charges. In any analysis of the resultant forces, there is no B field to consider. The E fields of the two charges are all we need. Got that?

 

[Reality Check]

Observations back up electron models proposed by the likes of Williamson and van der Mark. ...

Followed by a list of observations that have nothing to do with the invalid paper of Williamson and van der Mark (or their "likes") !
Reading the models proposed by the likes of Williamson and van der Mark shows that they fail at the first hurdle - they cannot match the observation that the electron has spin 1/2 and photons have spin 1 !

You refer to a paper and still do not understand that it is fatally flawed after 4 years! ctamblyn's post from 25th March 2010 There are two basic mistakes they have made, aside from their semi-classical treatment of the photon...

Every person in the world who can read and understand physics insists that the electron is treated as a point particle in quantum mechanics. They can see for example that the wavefunction involves the position of particles.

Every person in the world who can read and understand physics insists that the electron has the properties of both a particle and a wave. They would think that it is insane to only look at the wave properties and assert that the electron is a wave, which no one in this thread (except Farsight ) is doing. They would think that it is insane to only look at the particle properties and assert that the electron is a particle, which no one in this thread is doing .

 

[Reality Check]

No, but Heaviside understood electromagnetism, and was able to develop gravitomagnetism as a result.

Heaviside and every other scientist in 1893 understood electromagnetism, Farsight!

Heaviside was interested in the analogy between electromagnetism and classical gravitation (GR was a decade away).
O. Heaviside (1893). "A gravitational and electromagnetic analogy". The Electrician 31: 81–82.
He was not even the first person to wonder about the analogue: See the introduction to Gravitoelectromagnetism: A Brief Review.

The extension of the analogue to GR (with the frame dragging that you are going on about incessantly for some reason) obviously came after the development of GR!