do the particles ever collide in QED

[Farsight]

You're bluffing again. You didn't understand the maths. That's why you had to ask me. Then you didn't understand my explanation of the maths because you didn't understand some of the concepts I used in the explanation.

Phooey. Quarkhead was bluffing with a mathsdump that nobody explained. Where did you explain any maths? Link to the post. You can't, because you're bluffing.

Actually, that equation is the explanation. Why? Because it defines what is meant by "electric field". The observable is the force. The field is a construct.

No, the field is the electromagnetic field and it's no construct, instead it's a state of space, just like Einstein said. The electron is field. Electromagnetic field. When two such fields interact with no initial motion the result is linear force. That's real too. But it isn't a field in that it isn't a state of space. It's a mathematical field in that you could assign a value and direction at every point in space, but the only physical physics fields there are electromagnetic fields.

In other words, nature is such that like charges repel and unlike charges attract. That gives us $$F$$ and the above equation then defines $$E$$ for us. See?

No. You tell me why like charges repel and unlike charges attract. I've told you my version. Now you tell me yours. And don't just try to palm me off with some it-just-is equation that says like charges repel unlilke charges attract.

You can't either. If you think you can, give me an experimental test using only the force observable that will tell the difference.

No I can't. But I'm the guy who removed the arrowheads. It was me who said that neither the force nor the field point outwards or inwards.

I already agreed it has an electromagnetic field. That electromagnetic field is simply the electric field for a stationary charge.

The electron doesn't have an electric field, it has an electromagnetic field. So electric charge is a misnomer. It's electromagnetic charge. So the notion of magnetic charge is junk. As are magnetic monopoles, because there are no roller bearings of space in space.

You keep repeating yourself. Assertion without proof meets assertion without proof. Stalemate. See how this works?

This works via you denying the bleedin' obvious. Something over there doesn't change because you decided to move. You do not create a magnetic field for an electron by moving. It's got an electromagnetic field. It always had, regardless of how you perceived it.

You've linked to some guy who produced a theory of gravity (gravitomagnetism) that is demonstrably incorrect. And regarding his electromagnetic equations, perhaps you can explain why the potentials at time $$t$$ depend on an arbitrary past time $$t_r$$.

No. You're in denial again. You are denying the whole ethos of electromagnetism, which is that the field is the electromagnetic field. Here, see this: "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."

Maxwell's equations are consistent with electromagnetic waves. In fact, Maxwell himself discovered such waves as a result of formulating his equations.

Yes, and they're electromagnetic waves. Not electric waves and magnetic waves.

You really had no idea where to pitch your explanations when you talk to me, do you? You have no way of judging my level of knowledge. I throw mathematics at you, but since it's all a mystery to you, you think I'm lost in a world of mathematics and don't know the basic physics that precedes the mathematics. So one minute you try to bluff like you have a graduate-level understanding of things like relativity, and the next you think you need to explain school-level basics because I won't know them. The only explanation for such behaviour is that you're not sure what is school-level material and what is graduate level stuff. Because on wikipedia, your main source, it's all mixed in together. You can only cut and paste the pictures and some quotes. You have to skip over the maths because you don't understand it.

I understand quite enough of the maths thanks.

Anyway, back to the topic. When a charged particle goes around the magnetic field lines, the magnetic force on it at each point in its trajectory points radially inward. The force isn't a "twirly" force, or a "twisty" force or a "turn force" or a "screw force". It's just the usual kind of linear force. However, the force varies with position in such a way as to produce circular (or helical) motion.

Yeah, we know that. It makes the electron go round a magnetic field line.

I thought as much. In future , don't use terms you don't understand, Farsight. You'll get caught out again.

LOL, you haven't caught me out. You said Define "chirality" for me, please. I said no, I'm still saying no. Now go and look it up.

My question was a simple one: at a single point in space at which there is (part of) an electromagnetic wave, the electric field is at right-angles to the magnetic field. In such a case, which way does the "electromagnetic field" point?

The electric field isn't at right angles to the magnetic field. There aren't two sinusoidal waves at right angles to one another playing dozy-doh. What we say is the electric field variation is the spatial derivative of potential, whilst the magnetic field variation is the time-derivative of potential. As for which way it "points", that's a bit like asking which way an ocean wave points. It depends where along the wave we are, because it points like this ↖↑↗→↘↓↙←.

You have no idea about the maths I'm used to, not being able to do maths yourself. If you can't even get the dimensions of E and B correct, you're a lost cause I'm afraid, Farsight. I shouldn't have to explain such a basic thing to you twice.

You've explained nothing.

 

[QuarkHead]

Huh? You're talking about the divergence of the curl being zero.

I am. Do you want me to show you the proof? div(curl F) = 0 for any field F

What do you want me to tell you about the curl of the divergence?

Since you've thrown in the towel, let me explain

For any vector field F, then div F is a scalar field. But the curl operator takes only vector fields as "input", so curl(div F) is without meaning

 

[PhysBang]

And you've just admitted you've never followed up on any of my references to Einstein or Minkowski or Maxwell or anybody or anything else. Ye Gods. No wonder it's so difficult to teach you anything.

Farsight, many of us have already read the legitimate sources you cite. You link to so many crank sources that it is conceivable that your links might lead to spam or virus laden websites, so I can understand QuarkHead's trepidation. But regardless of your sources, you have yet to produce evidence. Whenever someone asks you for the details of your position, you dodge the question.

Compare with my picture:

Maxwell produces a picture to help explain his equations. You have no equations. Where are your details?

This works via you denying the bleedin' obvious. Something over there doesn't change because you decided to move. You do not create a magnetic field for an electron by moving. It's got an electromagnetic field. It always had, regardless of how you perceived it.

Here you are, as usual, denying Einstein's Special Relativity. It is somewhat sad.

LOL, you haven't caught me out. You said Define "chirality" for me, please. I said no, I'm still saying no. Now go and look it up.

The real question here is how you use "chirality", Farsight. You have yet to show us how to use the idea to do any physics. You have been asked several times to do so. You could even pick the application to describe. Yet you seem unable to do the most basic physics with your ideas.

 

[krash661]

And don't just try to palm me off with some it-just-is equation [...]You've explained nothing.

did you, of all people, just say this ?
hilarious.

 

[Farsight]

I am. Do you want me to show you the proof? div(curl F) = 0 for any field F

Yes. Go for it. For any field.

Since you've thrown in the towel, let me explain

For any vector field F, then div F is a scalar field. But the curl operator takes only vector fields as "input", so curl(div F) is without meaning

I haven't thrown in any towel. And you haven't explained anything. The electromagnetic field is a tensor field. The "electric field" is a vector field, only it isn't really a field because the electron has its electromagnetic field. Those radial lines aren't field lines, they're lines of force. They depict the force between two electrons etc which have no initial passing motion. The concentric magnetic field lines are somewhat similar but the particle goes around 'em not along 'em. And when you chuck a positron past an electron you see both the linear and rotational motion. They do their little death dance because that's what happens when electromagnetic fields interact. It takes two to tango. Have you got this yet?

...because it points like this ↖↑↗→↘↓↙←.

I don't suppose you remember Feynman's little rotating arrows?

 

[PhysBang]

So much for asking Farsight for details.

 

[QuarkHead]

Yes. Go for it. (prove div(curl) = 0}For any field.

Are you sure? Well here goes...

I suppose a field $$F$$ in 3-space whose components I write as $$F_x,\,F_y,\,F_z$$.

I define the divergence div of this field as $$\frac{\partial F_x}{\partial x}+\frac{\partial F_y}{\partial z}+\frac{\partial F_z}{\partial z}$$

I define the curl of this field as $$(\frac{\partial F_z}{\partial y}- \frac {\partial F_y}{\partial z})+ (\frac{\partial F_x}{\partial z}- \frac{\partial F_z}{\partial x}) + (\frac{\partial F_y}{\partial x}-\frac{\partial F_x}{\partial y})$$

So that, div(grad) after gathering terms and simplifying is $$\frac{\partial^2 F_x}{\partial z \partial y} -\frac{\partial^2 F_x.}{\partial y \partial z}$$ and so on,and since these partial derivatives commute, then this sum is zero

So div(grad) = 0 for any $$C^2$$ vector field

 

[Farsight]

For any C² vector field? But you said any field. And you said div(curl) not div(grad). You know Quarkhead, I think you have this concept in your head that fields are all to do with flow, like all that stuff about sources and sinks, and this. The latter is pretty good, but to further your education I need to shift you onto a different concept of what a field is. It's a "state of space", and space is like this ghostly gin-clear elastic. I tell you what, let's drop down to two dimensions and use that old favourite, the rubber sheet. This represents space. OK, you know one of those rotational floor polishers? Imagine I'm holding one firmly against the rubber sheet. It twists the rubber sheet around, like frame dragging. Like this:



It's like Maxwell's little picture showing divergence and curl. But there's no arrowheads, because the rubber sheet isn't flowing or rotating in any sense. OK it moved when I applied the floor polisher, but forget that. Forget the floor polisher too. Focus on the rubber sheet. It's now static, and it's stressed in a spiral fashion. Now try describing its state in terms of div and curl. And note that it's neither flowing nor rotating.

 

[PhysBang]

No, sorry. I don't know how to describe this 3D optical-vortex standing-wave standing-field-structure mathematically.

Since you have admitted that you don't know the mathematics to make these pictures into physics, why bother?

 

[QuarkHead]

For any C² vector field? But you said any field.

Then show me a field that not $$C^2$$

And you said div(curl) not div(grad).

Anyone with half a brain would have realized these are genuine typos. Is this the best you can do?

Incidentally, div(grad) is commonly referred to as the Laplacian, and has some interesting properties

I think you have this concept in your head that fields are all to do with flow,

I have no idea where you get that idea from. I suggest you do not try for a career in mind-reading

a field is..... a "state of space",.

I know of no mathematician, living or dead, who would agree with this. I doubt any physicist, chemist or population biologist would either. Perhaps you could be a bit more precise with this "definition"

I gave you one that is widely accepted and seen as useful. The one I gave is not without its shortcomings - it relies entirely on the somewhat problematic Axiom of Choice, and I know of a better one.

You know, ignorance can be cured, but only if the patient takes the prescription. In such a case one is inclined to call the patient stupid

 

[QuarkHead]

Then show me a field that not $$C^2$$

P.S. Since I am unable edit mine own post, show me the divergence and curl of a scalar field

 

[Arlich Vomalites]

If it isn't rotating, the electron isn't an electron, it's a photon.

No. If the electron is not rotating, it is still an electron. That is what the spin 1/2 means. Spin 1 means that
it is always rotating, for example the magnetic field.

But the quantum of the electric field is a massless femion, having the spin 1/2, meaning that the electric field
does not rotate like the magnetic field.

What is the quantum of the magnetic field?

It isn't fundamental. You can create charged particles in pair production. And you can destroy that charge in annihilation.

Charge is fundamental. You are telling that you can create charge in pair production, but you are actually
telling a chicken and egg paradox. Do you think that the loops in these Feyman diagram go on forever,
that you have endless time to perform your magic of creating charge out of light :
http://www.iue.tuwien.ac.at/phd/pourfath/img560.png

I know.

No, you don't know. Charge does not come from rotation.

Yes. And we create the electron and the positron out of light in pair production. We had something that was moving linearly at c, and then we've got something with spin ½. And a magnetic moment. Which we can diffract. Then after electron-positron annihilation we've got photons again. You don't have to be the brain of Britain to work out that the electron is a wave in a closed path.

You are telling nothing but a chiken and egg paradox. It is not a solution to anything. Light creates a pair
of electron-positron, which annihilate back into light , which creates a pair of electron-position, which
annihilate back into light, and so on for ever.............

A wind.

A wind does not rotate a half of an circle. Unless something is artifically forcing air to move through a path of
half a circle, but then it is not called wind, it is just a flow of air. What you got is a half of a cyclone when
it does only 180 degrees of rotation.

No. But that is the difference between the electron and the positron.

No, rotation is not the difference between a positron and an electron. The difference between them is
negativity and positivity.

What is the difference between warm and cold? Rotation?

 

[Farsight]

Then show me a field that not $$C^2$$ Anyone with half a brain would have realized these are genuine typos. Is this the best you can do? Incidentally, div(grad) is commonly referred to as the Laplacian, and has some interesting properties I have no idea where you get that idea from. I suggest you do not try for a career in mind-reading

Bah. You slipped up more than once.

I know of no mathematician, living or dead, who would agree with this. I doubt any physicist, chemist or population biologist would either. Perhaps you could be a bit more precise with this "definition"

You've led a sheltered life. See Einstein talking about gravitational and electromagnetic fields here:

Expanding the Theory.
This theory having brought together the metric and gravitation would have been completely satisfactory of the world had only gravitational fields and no electro-magnetic fields. Not it is true that the latter can be included within the general theory of relativity by taking over and appropriately modifying Maxwell's equations of the electro-magnetic field, but they do not then appear like the gravitational fields as structural properties of the space - time continuum, but as logically independent constructions. 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.[/I]

I gave you one that is widely accepted and seen as useful. The one I gave is not without its shortcomings - it relies entirely on the somewhat problematic Axiom of Choice, and I know of a better one. You know, ignorance can be cured, but only if the patient takes the prescription. In such a case one is inclined to call the patient stupid

Huh? Don't you call me stupid.

P.S. Since I am unable edit mine own post, show me the divergence and curl of a scalar field

No. I asked you to do something first, and I've given you the Maxwell and Einstein references. Tell me about the divergence and curl of space in this state:

 

[Farsight]

No. If the electron is not rotating, it is still an electron. That is what the spin 1/2 means. Spin 1 means that
it is always rotating, for example the magnetic field.

No it doesn't. But it would seem that you're going to believe whatever you think regardless of anything I say, and regardless of any references I provide. So let's leave it at that.

 

[krash661]

QuarkHead↑
I gave you one that is widely accepted and seen as useful. The one I gave is not without its shortcomings - it relies entirely on the somewhat problematic Axiom of Choice, and I know of a better one. You know, ignorance can be cured, but only if the patient takes the prescription. In such a case one is inclined to call the patient stupid

Huh? Don't you call me stupid.

why not ?
it's the reality.

 

[OnlyMe]

You've led a sheltered life. See Einstein talking about gravitational and electromagnetic fields here:

Expanding the Theory.
This theory having brought together the metric and gravitation would have been completely satisfactory of the world had only gravitational fields and no electro-magnetic fields. Not it is true that the latter can be included within the general theory of relativity by taking over and appropriately modifying Maxwell's equations of the electro-magnetic field, but they do not then appear like the gravitational fields as structural properties of the space - time continuum, but as logically independent constructions. 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.

The link the above quote comes from begins with,

Einstein's Theory of Relativity (February 3, 1929) presented to the general public, in terms that the average person could understand (or so he thought).
​

Who would have thought Einsein knew you would be reading it? Note the portion in bold!

Almost every time I read one of your posts these days I am reminded of one of rpenner's posts in another thread,

The sterility of an argument from authority is probably not obvious to those that have never supported empiricism. You have to have an open mind and an ability to fairly weigh the evidence and arguments for both sides of a proposition before judging it as acceptable, possibly acceptable at some later date, or unacceptable.

A purported quote or other reliance on an authority figure is not the same thing as a well supported argument based on all the evidence. For one, the authority is necessarily rooted in the past and may have not had access to the modern totality of evidence. Secondly, even the best authorities get things wrong in ways small (typos) and large (misguided rejection of well-supported arguments). Thirdly, some authorities speak on a wide range of topics, including those where they have no basis. Fourthly, some authorities write on their subject matter for average audiences in quite a different manner than to their fellow experts, because they know only a dilettante would refuse to look past some popular press explanation or analogy. And finally, distortions intentional and accidental happen when an authority's statement in the past is transcribed, translated, edited, quoted, paraphrased, cited and interpreted.

 

[Arlich Vomalites]

No it doesn't. But it would seem that you're going to believe whatever you think regardless of anything I say, and regardless of any references I provide. So let's leave it at that.

Yes, I am ignoring what you say simply because you are wrong, and it is you who believes whatever you think regardless of anything anyone says.

 

[PhysBang]

Bah. You slipped up more than once.

That is not an answer to the question of C^2 fields. Can you produce one of interest that is of significant interest? Then can you show the relevant mathematical properties for that field and for the C^2 fields?

Tell me about the divergence and curl of space in this state:

That is a crazy question, since you have never provided enough information about your pictures to use them in a mathematical way. I have asked you repeatedly to show us how to do a simple physics problem with your pictures and you have dodged the question every time. You lie and claim that your pictures have something to do with mathematical terms, but your behavior indicates your inability and your lies.

 

[QuarkHead]

Huh? Don't you call me stupid.

Why ever not? I asked you about the divergence and curl of a scalar field, and you couldn't answer, in spite of me explaining the domain and codomain of these differential operators. Diagnosed patient refuses to take medication

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.

And this you present as a "proof" that a field is a state of space. I read it twice, and I still see no such assertion. And even if I did - may the saints preserve me - I would disagree.

You were given a definition of a field, which you ignored, Patient refuses to take medication/

Diagnosis: Stupidity

Prognosis; Terminal

 

[Farsight]

Why ever not? I asked you about the divergence and curl of a scalar field, and you couldn't answer, in spite of me explaining the domain and codomain of these differential operators. Diagnosed patient refuses to take medication

Er, no, you tried to avoid my question by posing one of your own. The divergence of a scalar field doesn't make sense. And now with all this "diagnosed patient" nonsense you're hurling abuse because you're in a corner again.

And this you present as a "proof" that a field is a state of space. I read it twice, and I still see no such assertion. And even if I did - may the saints preserve me - I would disagree.

Einstein said a field was a state of space. You've got a gravitational field in the room you're in because the space in that room is inhomogeneous. If the space didn't have that state, the field wouldn't be there.

You were given a definition of a field, which you ignored, Patient refuses to take medication/

Your definition is an abstract definition that is not in line with Einstein. It's a mathematical definition that allows for such niceties as a "wind field".

Diagnosis: Stupidity

Aw, you're doing a runner again. Duck the question, hurl abuse, and leg it.