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"Veritasium" (YT) - "The Big Misconception About Electricity" ?
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aetherist:

--- Quote from: TimFox on March 11, 2022, 09:43:30 pm ---Heaviside's solution for cables led further to the development of continuous transmission lines.
These are rather important things to understand in connection with speed of electrical information transmission.
--- End quote ---
Heaviside found it easy to avoid the elephant in his room re the insulation paradox re the speed of electrical information transmission koz in his coaxial cables the insulation filled the whole space tween the core & the sheath.
But the elephant emerges when we have ordinary (non-coax) wires with thin layers of insulation.
At which time the speed of light in the thin layer of insulation trumps the speed of light in the air which fills over 99% of the space.

Yes, Heaviside would have been impressed with my electons (ie photons hugging the wire). At least he would be impressed after i explained what a photon was. But i wouldn’t have to explain aether, he knew about aether.

I would have to explain that in the modern era Einsteinists don’t believe in aether, & that Einsteinist's had taken over science. Actually i wouldn’t need to explain much, koz Heaviside knew about Einsteinist's when Heaviside died in 1925, & i feel sure that Heaviside thort that STR & GTR were krapp, but Heaviside would have been shocked that Einsteinist's took over in the late 1920's, especially after Einstein died in 1955, & he would have been shocked that the Einsteinian Mafia were still in control in the 2020's.
adx:
Belated and somewhat patchy or even redundant-ish reply, but here goes:


--- Quote from: HuronKing on March 10, 2022, 05:35:06 pm ---There is a degree of 'leap-frogging' between experimentalists (sometimes this includes the engineers) and theoreticians. For example, we knew about the photoelectric effect before Einstein's paper on it. And some physicists (namely Planck) were already toying around with the idea of discrete quanta. But I'd make a strong argument that this singular statement by Einstein changed the world,

--- Quote ---Energy, during the propagation of a ray of light, is not continuously distributed over steadily increasing spaces, but it consists of a finite number of energy quanta localised at points in space, moving without dividing and capable of being absorbed or generated only as entities.
--- End quote ---

Of course it wasn't immediately accepted - new experiments were needed to verify this interpretation. But, it predicted the effects of Compton Scattering. And this explanation of the photoelectric effect not only underpinned quantum mechanics (the basis for transistors) but also gave basis for the engineering of image sensors, phototelegraphy, etc etc.

--- End quote ---

On one hand yes, a basis. But what is a basis? Theoretical? Foundational? Occupational?

Selenium cells were in use 30 years before that, and in futuristic 'practical' applications like the photophone in the same year as Einstein's paper:
https://en.wikipedia.org/wiki/File:Ernst_Ruhmer,_Technical_World_cover_(1905).jpg

These cells were also apparently in use as rooftop PV solar in 1884:
https://en.wikipedia.org/wiki/Charles_Fritts
(Although I am a bit sceptical of the references because some claim it was thermopile based - Wikipedia isn't always right.)

It's a weak argument to say that the subsequent quantum theory gave basis for extant devices and applications - even if those applications later benefited enormously. Just because it was noticed and described, doesn't mean it works any different at any time. The theory becomes a guide for unchanging empirical behaviour, once people are on its scent. I don't accept that this 'scent' is academic theory, except in special cases where it is.

I accept the leap-frogging effect, I accept the greater advances, I even accept that a technology could stall at some point without the theory. But I can't accept that the latter is unavoidable, and I think that things like Wikipedia articles which begin and end on the equations are a disservice to the field(s).


--- Quote from: HuronKing on March 10, 2022, 05:35:06 pm ---Your example of the iPhone is not an example of an advancement in physics. No new laws or phenomena were discovered or predicted by its creation. Quite the contrary - the iPhone is a culmination of the application of many diverse phenomena well-established and predicted by physics.

--- End quote ---

The latter is what I meant. That the iPhone doesn't definitively owe its existence to predictions of physics and academic process, unless you want to take the position that any one link in the chain could be undone if it wasn't for some glorious crystal of theory (like Maxwell's equations, say, or something which 'makes' fets work especially at 5nm). People tend to push through those kinds of things if they can see a way past. Or if you want to say we wouldn't have the iPhone today, which is obvious.

I certainly don't want to say physics had no part or is dead. The only thing I want to target is this (I assume) taught notion that science begat physics begat engineering that doesn't seem to exist outside of academia and governmental ivory towers. The commercial world is completely indifferent to that, and simply assumes that physics is one of the parts of engineering.

Claims that "physics had to come before technology" can be made arbitrarily, eg fax machines might have stepper motor drivers, image sensor chips and even lasers. But when it's said that optical fax existed in the late 1800s, those claims need adjustment. They might still be correct, but it doesn't have much meaning.

Re Heaviside, he usually is called a physicist, but before that was recognised, he was shunned by just about any institution (but not person) that could exist. He was an electrician (possibly more in line with an electrical engineer today). Patenting the coaxial cable sounds awfully like engineering to me. So do eschewing some mathematical rigour, and getting into spats with an ignorant boss. And so on. My point being that this distinction can be imaginary (or perhaps arbitrary).

Denying physics would be completely silly, but I don't think that's what I'm saying. It's certainly not what I want to suggest or portray.
Alex Eisenhut:
What property of electons and aether give the same size bare wire made of different metals have different resistance?
aetherist:

--- Quote from: Alex Eisenhut on March 13, 2022, 03:51:02 pm ---What property of electons and aether give the same size bare wire made of different metals have different resistance?
--- End quote ---
Good question.
Naturally to give a good answer i had to firstly see (understand) how old (electron) electricity answered the question.
After that it was a good idea to see how new (electon) electricity compared, point by point.
Straight away i hit a snag, i had trouble understanding the old (electron) electricity Wiki explanation for resistance.

https://en.wikipedia.org/wiki/Electrical_resistivity_and_conductivity
In metals.
[000 ] Like balls in a Newton's cradle, electrons in a metal quickly transfer energy from one terminal to another, despite their own negligible movement.
[00 ] A metal consists of a lattice of atoms, each with an outer shell of electrons that freely dissociate from their parent atoms and travel through the lattice. This is also known as a positive ionic lattice.[10]
[0 ] This 'sea' of dissociable electrons allows the metal to conduct electric current.
[1 ] When an electrical potential difference (a voltage) is applied across the metal, the resulting electric field causes electrons to drift towards the positive terminal.
[2 ] The actual drift velocity of electrons is typically small, on the order of magnitude of meters per hour. However, due to the sheer number of moving electrons, even a slow drift velocity results in a large current density.[11]
[3 ] The mechanism is similar to transfer of momentum of balls in a Newton's cradle[12]
[4 ] but the rapid propagation of an electric energy along a wire is not due to the mechanical forces,
[5a ] but the propagation of an energy-carrying electromagnetic field [5b] guided by the wire.
[6 ] Most metals have electrical resistance.  [7] In simpler models (non quantum mechanical models) this can be explained by replacing electrons and the crystal lattice by a wave-like structure. [8] When the electron wave travels through the lattice, the waves interfere, which causes resistance. [9] The more regular the lattice is, the less disturbance happens and thus the less resistance.
[10 ] The amount of resistance is thus mainly caused by two factors. [11] First, it is caused by the temperature and thus [12] amount of vibration of the crystal lattice. Higher temperatures cause bigger vibrations, [13] which act as irregularities in the lattice.
[14 ] Second, the purity of the metal is relevant as a mixture of different ions is also an irregularity.
[15 ] The small decrease in conductivity on melting of pure metals is due to the loss of long range crystalline order. [16] The short range order remains and strong correlation between positions of ions results in coherence between waves diffracted by adjacent ions.

[000 ] says that electrons transfer energy, via bumping.
[0 ] says that a metal can conduct electric current.
[1 ] says that electons drift koz of an electric voltage field.
[3 ] says the mechanism is similar to bumping. What mechanism? Voltage? Drift? Transfer of energy? Who knows!
[4 ] is confusing. It says that [4a] bumping does not propagate electric energy along a wire. Or, [4b] it says that bumping does not produce the rapid propagation seen of electric energy along a wire. Or [4c] perhaps both.
[5a ] is a killer. Just when u were getting used to words like Newton cradle electron drift wire electric energy conduction voltage field etc, it suddenly foists on us an energy carrying em field. [5b] guided by the wire. Where is this field? In the wire? On the wire? Around the wire? Is this energy electric energy? Does the field carry the energy? Or is the energy in the field? In other words duz the field possess the energy or does it simply transmit it, or perhaps both?
[6 ] to [16] tell us that resistance is due to irregularities inside the wire. Good, i was starting to panic.

Anyhow, Wiki says that energy is transferred by electrons, & it says that energy is not transferred by electrons.
Wiki says that voltage makes electrons drift, & it says that bumping makes electrons drift, & (i think) that it says that drift makes voltage. However, (i think that) Wiki duznt say that drift makes bumping (phew)(i was starting to panic).

Wiki says that silver has the best conductivity, & some metals are worse by a factor of 10 (lets call such a metal Tendium). This sounds bad for electons.
Old (electron) electricity can of course say that the factor of 10 is due to irregularities in the metal/wire.
New (electon) electricity (being on the surface of a wire) needs to do some fast talking.
I suppose that the simplest answer is that the irregularities in the thin skin of the wire is much the same as the irregularities deeper in the wire.
But why would electons (ie photons) be slowed by irregularities in the skin of the wire?
Problem 1.   If Tendium has 10 times the resistance, it has 10 times the heat loss, & perhaps it should have 1/10th the speed of electricity. But i think that the speed of electricity is much the same in/on/for every metal (is it?).
The problem for electons is that extra resistance of a wire & extra heat loss duznt slow the speed of electricity along the wire.

Problem 2.   Does a photon passing through glass heat the glass? I think not (or perhaps it duz). But the photon is slowed by glass.
A photon (electon) passing along a wire heats the wire, but it is not slowed. Whats going on? Still thinking.

Problem 3.   An electon passing along an insulated wire heats the wire at the same rate as a non-insulated wire, yet the speed of electricity is say 2c/3.
Problem 4.   Shouldn’t the heating be 3/2 times the heating for a bare wire?
Problem 5.   Shouldn’t the extra ½ of heat be in the insulation? Is it? Still thinking.

My new (electon) electricity says that electons can saturate the surface of a wire. No more electons can fit on the surface, unless the voltage is increased.
Electons have a negative charge, hence they would tend to jump onto a surface & distribute on a surface much like free surface electrons might. Except that at equilibrium electrons might be static, whereas electons are always propagating at the speed of light (they are photons)(albeit semi confined, hugging the wire).

Problem 6.   Electons are a surface dweller, hence u would think that doubling the dia of a wire would halve the resistance. If doubling the dia results in a ¼ resistance then electons are in trouble.  For DC current.

New (electon) electricity is a work in progress. I need to find the boxes [problems], & then i need to work out how to tick the boxes.
adx:

--- Quote from: aetherist on March 13, 2022, 10:07:27 pm ---[5a ] is a killer. Just when u were getting used to words like Newton cradle electron drift wire electric energy conduction voltage field etc, it suddenly foists on us an energy carrying em field. [5b] guided by the wire. Where is this field? In the wire? On the wire? Around the wire? Is this energy electric energy? Does the field carry the energy? Or is the energy in the field? In other words duz the field possess the energy or does it simply transmit it, or perhaps both?

--- End quote ---

I agree. The description is completely opaque at this point. I don't accept any argument that the only way of explaining it jumps to mathematical at this point. If the phenomenon is a physical phenomenon, it can be described without discontinuity, otherwise a leap to mathematics could be called "hand-waving" at some level similar to "trust us, this is how the theory works, and it does". Whether our minds wish to find that description "intuitive" or not is another matter. This is not a popularity contest, as far as I am concerned the theory works and should be describable.


--- Quote from: aetherist on March 13, 2022, 10:07:27 pm ---I suppose that the simplest answer is that the irregularities in the thin skin of the wire is much the same as the irregularities deeper in the wire.
But why would electons (ie photons) be slowed by irregularities in the skin of the wire?

--- End quote ---

That doesn't work if the surface is plated with a highly conductive metal, eg silver on steel. The resistance except at very high frequencies (skin effect) is that of the bulk steel wire.


--- Quote from: aetherist on March 13, 2022, 10:07:27 pm ---Problem 2.   Does a photon passing through glass heat the glass? I think not (or perhaps it duz). But the photon is slowed by glass.

--- End quote ---

Consider a transmission line, lumped model is ok. Energy propagates via transfer between Ls and Cs. Adding resistance doesn't fundamentally slow that.


--- Quote from: aetherist on March 13, 2022, 10:07:27 pm ---Problem 6.   Electons are a surface dweller, hence u would think that doubling the dia of a wire would halve the resistance. If doubling the dia results in a ¼ resistance then electons are in trouble.  For DC current.

--- End quote ---

Well spotted.
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