Merged Relativity+ / Farsight

[Roboramma]

Farsight: "But nobody will depict electromagnetic field lines or talk sincerely about this subject."

You haven't even addressed the criticisms of your approach: specifically that any 2D diagram of the electromagnetic field that tries to put it all together in to one set of field lines will necessarily lose some of the information about the electromagnetic field. How can a diagram which doesn't contain all the information about the electromagnetic field be said to be diagram of the electromagnetic field, and what would be the purpose of drawing such a diagram?

From where I'm sitting it seems to me that if anyone isn't "talking sincerely about this subject" it's you.

 

[ctamblyn]

Yes. It demonstrates that the forum is a platform for anonymous slander...

You might want to check the definition of slander...

Edd: The current-in-the wire is a different situation.
...
I spoke about this in the opening posts. Obviously you didn't read it.

Isn't that the same edd who wrote post #5?

...
But nobody will depict electromagnetic field lines or talk sincerely about this subject.

A correct description of the electron's field was first given to you in post #3 (the very first reply to you in this thread). We've also given you mathematical descriptions of the field over and over again in various equivalent forms (you know, the stuff we can use to come up with testable predictions and practical applications). Most recently, there's the diagram in post #1694.

But rather than something relating to reality, you apparently want something which reduces 6 pieces of data at each point to 3, without losing any information.

Nobody will step up to the plate about electrons and positrons slinging photons back and forth.
...

I seem to remember ben m explaining this to you.

Ah yes, virtual particles were first mentioned in post #65, to which you never replied.

And again in post #1376 (I'm sure there are more instances in this thread, but I got bored of searching).

And again in this post, this post and this post (all in the "Why is there so much crackpot physics?" thread).

One last thing - should you return, don't forget these questions: http://www.internationalskeptics.com/forums/showthread.php?p=9997976#post9997976

 

[kmortis]

Being challenged is not...no, that will never do.

Being challenged, even if the language of that challenge is not to your liking, is not abuse. Vis:
1) The Dunning-Kruger effect is an example of crack-pot psychology.
2) You are a crackpot if you believe the Dunning-Kruger effect is real.

Under normal circumstances, #1 is acceptable and #2 is not. 1 is attacking the argument; 2 is attacking the person. Whilst is is possible for #1 to stay into the semantic arena of abuse, that has not happened in this thread.

Now, either get back to discussing...um, whatever it is you lot are discussing, or I shall pull this thread over to the side of the forum and the offending parties will really be sorry.

Unnastand?

Replying to this modbox in thread will be off topic  Posted By: kmortis

 

[W.D.Clinger]

Maxwell's screw analogy was just an analogy

Yesterday, writing about Part IV of Maxwell's "On Physical Lines of Force", I made a mistake:

Maxwell had begun that section by stating equations (9), which looks to be a statement of the part of the Lorentz force law that's due to the magnetic field alone.

No, equations (9) was the original form of Ampère's circuital law, without Maxwell's correction.

Maxwell had introduced his correction earlier, in equation (112) of part III. In part IV, Maxwell deliberately restated equations (9) in uncorrected form.

Why? Because he wasn't really talking about the electromagnetic field. He was merely drawing an analogy between the electromagnetic field and other "pairs of phenomena, of which one has a linear and the other a rotatory character." Maxwell enumerated three non-EM examples of such phenomena immediately following his restatement of equations (9).

A more accurate description of the electromagnetic field would have interfered with his analogy.

 

[Perpetual Student]

Being challenged is not...no, that will never do.

Being challenged, even if the language of that challenge is not to your liking, is not abuse. Vis:
1) The Dunning-Kruger effect is an example of crack-pot psychology.
2) You are a crackpot if you believe the Dunning-Kruger effect is real.

Under normal circumstances, #1 is acceptable and #2 is not. 1 is attacking the argument; 2 is attacking the person. Whilst is is possible for #1 to stay into the semantic arena of abuse, that has not happened in this thread.

Now, either get back to discussing...um, whatever it is you lot are discussing, or I shall pull this thread over to the side of the forum and the offending parties will really be sorry.

Unnastand?

Replying to this modbox in thread will be off topic  Posted By: kmortis

Retiring this tread would not be much of a loss.
Frankly, this is a tired tread, recycling the same old pseudo-scientific conjectures over and over.

 

[ben m]

It got moved to AAH, but Farsight's last post (which ctamblyn quotes) announced

a) He was bailing out of the thread because it's become repetitive.
b) He thinks none of his questions have been answered seriously
c) He still thinks the "electromagnetic field" has simple field lines; i.e., he still thinks it's a vector field.

This is all nonsense, of course. He's bailing out of the thread because there was no longer the slightest hope of escaping the embarrassment of defending his self-contradictions. (He bailed out of the Early Universe thread in the same way---right after his self-contradicting baloney got quoted back at him, he decided he had "said his piece") His questions were answered; what he means is that he didn't get the answers he was fishing for. (AKA "Gosh, Farsight, you're right, your vague incredulity about the photon-tennis explanation has clearly invalidated QED entirely.") And the electromagnetic field does not have "lines"; vector fields can have lines, tensors cannot, and Farsight doesn't have the math training to understand what that means.

 

[Perpetual Student]

It got moved to AAH, but Farsight's last post (which ctamblyn quotes) announced

a) He was bailing out of the thread because it's become repetitive.
b) He thinks none of his questions have been answered seriously
c) He still thinks the "electromagnetic field" has simple field lines; i.e., he still thinks it's a vector field.

This is all nonsense, of course. He's bailing out of the thread because there was no longer the slightest hope of escaping the embarrassment of defending his self-contradictions. (He bailed out of the Early Universe thread in the same way---right after his self-contradicting baloney got quoted back at him, he decided he had "said his piece") His questions were answered; what he means is that he didn't get the answers he was fishing for. (AKA "Gosh, Farsight, you're right, your vague incredulity about the photon-tennis explanation has clearly invalidated QED entirely.") And the electromagnetic field does not have "lines"; vector fields can have lines, tensors cannot, and Farsight doesn't have the math training to understand what that means.

Exactly!

 

[The Man]

Thanks for pointing this out, ben m.
Here we have Farsight saying:

and then he goes on to talk about corotating vortices repelling, but when I point out that corotating magnetic fields around currents in wires cause them to attract suddenly it's

It's even in the same page of the thread.

I think that is a critical part of his problem edd. The fact that is is purportedly the magnetic component of the field that carries the non-radial contributions. Yet when the magnetic component dominates to provided the very type of magnetic field he depicts (current in a wire) the 'co-rotating fields repel' assertion evidently doesn't hold. We also have that very inclusion of the current in a wire field as opposed to the characteristic traits of a dipole field. Who's non-radial components would (by virtue of having the two poles) curve one way on one side and the other way on, well, the other. Farsight, by making his vortex spin one way for one charge and the opposite way for the opposite charge, is indeed attempting to establish an electromagnetic mono-pole.

 

[DeiRenDopa]

Here you go, since I had a spare minute at a capable box.
[qimg]http://s30.postimg.org/fkin3jsnl/figure_1.png[/qimg]

Don't take any notice of field lines springing up out of nowhere. That's a figment of the plotting library trying to keep line density ~ constant. All field lines start and stop on the particle at the origin.

As discussed previously, two sets of vectors to express the 4 components of the tensor that are in this particular plane (chosen so that the dipole points in the y direction).

Very cool, edd!

Are there special pairs of orthogonal planes, in which the combined field looks similarly cool, visually?

So, this thread could have been sooo much shorter, if only someone had posted an image like this, several years ago?

 

[Turgor]

Very cool, edd!

Are there special pairs of orthogonal planes, in which the combined field looks similarly cool, visually?

So, this thread could have been sooo much shorter, if only someone had posted an image like this, several years ago?

well it's essentially a picture that looks like what ben m described in post #3

 

[DeiRenDopa]

Very cool, edd!

Are there special pairs of orthogonal planes, in which the combined field looks similarly cool, visually?

So, this thread could have been sooo much shorter, if only someone had posted an image like this, several years ago?

well it's essentially a picture that looks like what ben m described in post #3

True.

But no one actually produced such an image/picture, until very recently (as far as I know).

It would seem that, for Farsight, the logic of a visual image carries far more weight than all the words about tensors and vectors (the formulae etc don't count; they have zero impact, as is clear).

 

[Farsight]

Turning light into matter

There's been some science news stories about a Nature Photonics paper A photon–photon collider in a vacuum hohlraum. See the report from Imperial:

Scientists discover how to turn light into matter after 80-year quest:

"Imperial physicists have discovered how to create matter from light - a feat thought impossible when the idea was first theorised 80 years ago. In just one day over several cups of coffee in a tiny office in Imperial’s Blackett Physics Laboratory, three physicists worked out a relatively simple way to physically prove a theory first devised by scientists Breit and Wheeler in 1934..."

You can also google on "turning light into matter", but note that some of the reports are a little sensationalist, as if this is something totally novel. It isn't, see this report which also refers to SLAC and pair production:

Experiment to Turn Light Into Matter : Discovery News

Note the the bit that says "matter was first created out of pure energy in 1997 at the Stanford Linear Accelerator Center". However even that is arguably incorrect, see pair production, and read this about Patrick M.S. Blackett in 1933. It's the Blackett lab at Imperial for a reason. The general idea has been around for even longer than that. You can trace it back to 1704 and Newton's Opticks. See query 30 where Newton said "Are not gross bodies and light convertible into one another?" Matter is converted into light in something as simple as a fire. Not much, but that that's what E=mc² is all about of it. If you could collect all the ash and smoke and weigh it, it would weigh just a little but less than the original coal. It's somewhat similar for an atom bomb, where the conversion rate is about 0.1%, and similar again for matter-antimatter annihilation where the conversion rate is 100%. The inverse of this is the pair production which is "turning light into matter". Also see two photon physics on Wikipedia:

"Two-photon physics, also called gamma–gamma physics, is a branch of particle physics that describes the interactions between two photons. If the energy at the center of mass system of the two photons is large enough, matter can be created..."

Note thought that the article says "From quantum electrodynamics it can be found that photons cannot couple directly to each other". That's wrong. Pair production doesn't occur because pair production occurs, instead two photons interact. Recognition of this is the arguably the most important aspect of this news. It may lead to an important advance in physics.

 

[ben m]

There's been some science news stories about a Nature Photonics paper

Good for them. They take standard, well-known, well-tested quantum physics and use it to guide the design of a clever experiment. But the most surprising thing is ...

That's wrong. Pair production doesn't occur because pair production occurs, instead two photons interact. Recognition of this is the arguably the most important aspect of this news. It may lead to an important advance in physics.

... that Farsight wants to complain about mainstream QED again, and tell you about his photon model again, because the last time he told us about it (what, ten pages ago?) was so successful.

Oh, wait, no, that's not surprising at all.

 

[Reality Check]

Yes - standard quantum physics followed by the Farsight's usual ignorance of QED and even physics in general !
The fantasy that the release of chemical energy in fires is the release of nuclear energy (E=mc²)!
"If you could collect all the ash and smoke and weigh it," then it would weigh more than the original coal because the carbon is oxidized - the coal "absorbs" oxygen from the atmosphere. If you burn coal in an closed system then there is no change in weight.

Quote mining (lying about) Wikipedia remains bad: http://en.wikipedia.org/wiki/Two-photon_physics

From quantum electrodynamics it can be found that photons cannot couple directly to each other, since they carry no charge, but they can interact through higher-order processes. A photon can, within the bounds of the uncertainty principle, fluctuate into a charged fermion–antifermion pair, to either of which the other photon can couple. This fermion pair can be leptons or quarks. Thus, two-photon physics experiments can be used as ways to study the photon structure, or what is "inside" the photon

The relevant criticism of that article is the missing word "function" in "photon structure function".

The usual and irrelevant rant about pair production does not change the results of QED !

 

[BowlOfRed]

The fantasy that the release of chemical energy in fires is the release of nuclear energy (E=mc²)!

I didn't follow that from earlier. That doesn't seem to be a fantasy to me. Nuclear reactions aren't special in that regard. They are just so much more energetic that the mass differences can be measured, yes?

 

[ben m]

If you burn coal in an closed system then there is no change in weight.

Not sure quite what you're getting at, but there are several right and/or wrong interpretations and I think you have the wrong one.

If you have a one mole of C and one mole of O2 and turn it to one mole of CO2, its fermion content, baryon number, etc. etc. etc. are the same; it emits light/heat and the C+O2 system weighs approximately the same as the CO2 system. The energy is was not nuclear, it's chemical.

If you have a batch of C + O2 and turn it to CO2, well, you've changed the binding energy of a bunch of chemical bonds. Binding energy contributes to mass (a hydrogen atom weighs 13.7 eV/c^2 less than the sum of an electron and a proton). One mole of CO2 does weigh less than one mole of C and one mole of O2. The difference is about 390 kJ/c^2 or 4 nanograms per mole.

On the other hand, if you have a mole of C and a mole of O2 in a thermodynamically isolated box, and you burn it; inside the box you turn the C+O2 into the (390 ng lighter) CO2, but the resulting CO2 is hot and its extra kinetic energy is part of the mass of the box, so the mass of the box doesn't change.

However, I think you were (erroneously) disagreeing with interpretation #2.

 

[Reality Check]

Not sure quite what you're getting at, but there are several right and/or wrong interpretations and I think you have the wrong one.

My interpretation was about a thermodynamically isolated box, so the mass of the box does not change.

BowlOfRed also raises an issue about "weighing" the difference in a non-thermodynamically isolated box. Theoretically possible but AFAIK not practically possible.

 

[ben m]

My interpretation was about a thermodynamically isolated box, so the mass of the box does not change.

If true, this was obscured by your attempt to contrast chemical energy with nuclear energy. In a thermodynamically-isolated box, nuclear decays etc. don't change the box mass either.

 

[lpetrich]

Note thought that the article says "From quantum electrodynamics it can be found that photons cannot couple directly to each other". That's wrong. Pair production doesn't occur because pair production occurs, instead two photons interact. Recognition of this is the arguably the most important aspect of this news. It may lead to an important advance in physics.

Photons don't have direct interactions with each other. Period. Full stop.

There is absolutely zero evidence that they do, and Farsight's claimed evidence is successfully accounted for in other ways. Let's see how two photons and two electrons interact (positron = electron here).

I'll show how one does the calculations.

(Process rate or cross section) ~ (phase-space factor) * |interaction amplitude|²
The "phase-space factor" is a sum over final momenta. Strictly speaking, that's infinite, but it is canceled out by the final wavefunction getting diluted to zero. So one does this calculation in a box, a finite-sized region, and one finds that the box falls away from the final result.

Interaction amplitude ~ (final wavefunction) . (interaction terms) . (initial wavefunction)

For two photons and two electrons, one calculates their amplitude by multiplying:

• photon 1 wavefunction (vertex 1)
• photon 2 wavefunction (vertex 2)
• electron 1 wavefunction (vertex 1)
• electron 2 wavefunction (vertex 2)
• electron propagator (vertex 1, vertex 2)
• interaction vertex 1 (photon 1, electron 1, electron propagator)
• interaction vertex 2 (photon 2, electron 2, electron propagator)

and adding a repeat of that calculation with the two photons (or the two electrons) interchanged. In the () is what other item(s) that an item is connected to.

The electron propagator is for a virtual electron. A propagator is the strength of inserting a particle in one position and removing it from another position.

This interaction amplitude applies to all these processes:

• electron + photon -> electron + photon
• 2 electrons -> 2 photons
• 2 photons -> 2 electrons

where electrons include ordinary electrons and positrons.

 

[Farsight]

Photons don't have direct interactions with each other. Period. Full stop.

Photons do have direct interactions with each other. That's why this work is important.

...that Farsight wants to complain about mainstream QED again...

I'm pointing out an obvious problem. The given explanation says pair production occurs because pair production occurs. That's wrong. You know it's wrong. Well done for pointing out that RC was wrong by the way.

The fantasy that the release of chemical energy in fires is the release of nuclear energy (E=mc2)!

It's not "nuclear energy", and nor is it a fantasy. You burn something, light is released, and what you've got is a radiating body. Now, what happens to a radiating body? I know, let's take a look at Einstein's E=mc² paper. He wrote L rather than an E, and he said this:

"If a body gives off the energy L in the form of radiation, its mass diminishes by L/c²."