Electrons are round! - Page 1
Forum section: electronics / general

author: G7PSK
author_rank: Super Contributor
timestamp: July 07, 2023, 03:46:58 pm
content: New measurements on roundness of electrons.https://www.sciencenews.org/article/electron-round-new-measurement-matter-physics

author: themadhippy
author_rank: Super Contributor
timestamp: July 07, 2023, 04:30:41 pm
content: I call for equal rights for electrons who wish to identify as triangles.

author: Stray Electron
author_rank: Super Contributor
timestamp: July 07, 2023, 05:19:37 pm
content: Quote from: G7PSK on July 07, 2023, 03:46:58 pmAnd Pie R Squared.

author: xrunner
author_rank: Super Contributor
timestamp: July 07, 2023, 05:21:29 pm
content: Why are they round? Is it due to their gravity?

author: iMo
author_rank: Super Contributor
timestamp: July 07, 2023, 05:52:55 pm
content: Electrons are round because the scientists have to publish some results regularly (while receiving funding for their research from public sources usually)..

author: m k
author_rank: Super Contributor
timestamp: July 07, 2023, 06:34:01 pm
content: Point like objects can't be anything but like round.

author: E-Design
author_rank: Regular Contributor
timestamp: July 07, 2023, 06:40:35 pm
content: Point like objects cant be anything but point like.

author: TimFox
author_rank: Super Contributor
timestamp: July 07, 2023, 06:42:25 pm
content: Don't rely on the headline.The actual research result involved an upper limit on the dipole moment of the electron."Roundness" is not a real technical term in particle physics.

author: Bryn
author_rank: Regular Contributor
timestamp: July 07, 2023, 06:49:57 pm
content: I've always known that electrons are round, just by the diagram below:So this isn't anything new to me

author: Coordonnée_chromatique
author_rank: Frequent Contributor
timestamp: July 07, 2023, 08:05:54 pm
content: "an electric field would exert a torque on them, much as gravity topples an egg standing on its end"The gravity don't have any effect on the electrons shape ?

author: SiliconWizard
author_rank: Super Contributor
timestamp: July 07, 2023, 08:11:49 pm
content: Quote from: themadhippy on July 07, 2023, 04:30:41 pmYeah, what about the right for the Earth to identify as flat though?

author: ejeffrey
author_rank: Super Contributor
timestamp: July 07, 2023, 08:36:20 pm
content: Quote from: themadhippy on July 07, 2023, 04:30:41 pmKnock that shit out. You dont have to crap your nonsense in every thread.

author: m k
author_rank: Super Contributor
timestamp: July 08, 2023, 12:38:04 pm
content: What is solid?If nucleus is expanded to the size of a fist how far are the first two electrons?(estimation of statistical average)

author: Zero999
author_rank: Super Contributor
timestamp: July 08, 2023, 02:35:23 pm
content: Quote from: Bryn on July 07, 2023, 06:49:57 pmThat's wrong. Electrons don't orbit atoms like that.https://en.wikipedia.org/wiki/Atomic_orbital?useskin=vector

author: ebastler
author_rank: Super Contributor
timestamp: July 08, 2023, 05:49:49 pm
content: Quote from: TimFox on July 07, 2023, 06:42:25 pmApparently that's what we get from "Science News -- Independent Journalism since 1921". Looks like the termindependentmeans "We reserve the right to make up our own terminology if it helps with the clicks."

author: SiliconWizard
author_rank: Super Contributor
timestamp: July 08, 2023, 10:34:24 pm
content: Well, the article they cite is this:https://www.science.org/doi/10.1126/science.adg4084Scientific vulgarization has its limits.

author: Haenk
author_rank: Super Contributor
timestamp: July 09, 2023, 08:51:34 am
content: Quote from: Zero999 on July 08, 2023, 02:35:23 pmHumbug. How should that work, since we all know the earth is flat.

author: EPAIII
author_rank: Super Contributor
timestamp: July 10, 2023, 11:28:49 am
content: Round, smound; more important is electrons are yellow.

author: Simon
author_rank: Unknown
timestamp: July 10, 2023, 08:39:43 pm
content: Quote from: Zero999 on July 08, 2023, 02:35:23 pmit's the diagram that is shown to you when you first learn about how electrons distribute in layers, from that you are taught how many holes there are in the outer orbit layer allowing electrons from other atoms to pop in to say hi and thus form chemical bonds. Noble metals have complete layers, hence as on smart alec in my class joked, they don't lower themselves to mix with other elements.

author: TimFox
author_rank: Super Contributor
timestamp: July 10, 2023, 08:46:13 pm
content: Yes: it's a diagram of atomic shell structure, not an image of the atom.

author: SiliconWizard
author_rank: Super Contributor
timestamp: July 10, 2023, 08:57:07 pm
content: Electrons are just a fantasy anyway.We all know that all there is, a bunch of hugging photons.

author: AndyBeez
author_rank: Frequent Contributor
timestamp: July 10, 2023, 09:03:01 pm
content: I always thought that in the world of quantum physics electrons are probably 'around' - but not certainly. When  there is Quantum Entanglement, the whole shape argument turns into a lava lamp of inseparable possibilities. Except where there is entropy.Shutup you're doing my head in+EDIT Just been asked, if electrons are round, then why are phone batteries flat

author: ebastler
author_rank: Super Contributor
timestamp: July 11, 2023, 06:18:43 am
content: Quote from: AndyBeez on July 10, 2023, 09:03:01 pmOh, that's because the largeratomshave that pancake shape shown in Bryn's diagram above.

author: aetherist
author_rank: Frequent Contributor
timestamp: August 13, 2023, 11:17:11 pm
content: Quote from: SiliconWizard on July 10, 2023, 08:57:07 pmEverything is photons. There is no such thing as a solid little nut (electron) orbiting a nucleus.In an atom, what we have is a photon orbiting a nucleus. Let us name this an elektron. It has a negative charge. It radiates, & radiation needs energy. But, that radiation is little different to ordinary radiation that radiates from every photon all the time for ever. The energy comes from the aether, we dont know how. Elektrons migrating along in a wire give us (a slow) elektricity.When a photon forms a loop (by biting its own tail) then it makes an electron. Electrons have a negative charge. Electrons can sit on & migrate on a surface -- or fly throo space – they give us static charge -- & movement (on a surface)(or through space) gives us (a slow) electricity.The acceleration of an electron needs the input of energy. And apparently the acceleration of an electron needs additional input of energy to replace energy radiated by the acceleration.What standard science calls electricity in a wire is actually due to photons hugging the surface of a wire. Let us name these elektons. Elektons have a negative charge. Elektons propagate at the speed of light, & give us (fast) elekticity.Elektons & elektrons propagate at the speed of light all the time for ever, so in that sense there can be no acceleration of the propagation. But, elektons & elektrons can be made to change course or move or migrate, & i don’t know whether this requires input of energy.And, we have (fast) Elekticity, & (slow) Elektricity, & (slow) Electricity -- 3 kinds.And we can add the ionic form of (slow) electricity, where negative ions migrate -- this needs a new name -- iontricity praps.And we can add the positive ionic form of (slow) electricity, where positive ions migrate -- this needs a new name -- positricity praps.And if in the positricity the positive ions are simply protons then this needs a new sub-name -- protricity praps. So, we have 6 kinds of electricity.

author: TimFox
author_rank: Super Contributor
timestamp: August 13, 2023, 11:46:45 pm
content: Once again, if electricity “hugs the surface” of a wire, then why does the DC conductance (reciprocal of resistance) scale with the cross-sectional area, not the circumference?

author: aetherist
author_rank: Frequent Contributor
timestamp: August 14, 2023, 12:40:38 am
content: Quote from: TimFox on August 13, 2023, 11:46:45 pmInteresting -- are there good measurements?On the other hand -- why are lightning down conductors often flat strap?

author: aetherist
author_rank: Frequent Contributor
timestamp: August 14, 2023, 02:03:04 am
content: Quote from: G7PSK on July 07, 2023, 03:46:58 pmAn electron in an atom is a photon orbiting/hugging the nucleus. Best call this an elektron.We dont know the 3D size/shape/dimensions of a photon(s).And, an elektron would form a loop (the head chasing its tail). And, the loop would trace out a spherical path over time (as the loop wanders), but i daresay that-there sphere might not have a single fixed radius, it might be a fuzzy sphere.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: August 14, 2023, 02:44:40 am
content: Interesting how the dipole moment is conflated with physical shape. I have no idea if an electron has a physical shape, but just for a thought experiment can any of you imagine a perfect sphere of alnico or other magnetic material. In spite of its sphericity it has a strong magnetic dipole.

author: TimFox
author_rank: Super Contributor
timestamp: August 14, 2023, 03:33:06 am
content: Quote from: aetherist on August 14, 2023, 12:40:38 amOne of a myriad of sources for resistance of copper wire: do the math.https://commons.wikimedia.org/wiki/File:Copper_cable_resistance.jpgEdit: please ignore the chart in that file, and consult the one cited below.

author: aetherist
author_rank: Frequent Contributor
timestamp: August 14, 2023, 04:08:13 am
content: Quote from: TimFox on August 14, 2023, 03:33:06 amI did the math. That/there chart says that resistance decreases with radius R in a linear way.The circumference of round wire increases in a linear R way with radius.The area of a round wire increases in an RR way.Hence area has nothing to do with resistance.Circumference has everything to do with resistance.

author: Simon
author_rank: Unknown
timestamp: August 14, 2023, 06:14:55 am
content: Quote from: aetherist on August 14, 2023, 04:08:13 amI'll break the forum rules now and tell you that you are a fucking idiot! I don't know what math you are smoking but you are wrong. This is so basic that it is hard to explain to an idiot that will not listen!the area of a circle is r^2*pithe circumference is r*2*piNow if you were not an idiot you would spot the obvious! but you are a fucking idiot!!!You should, if you were not a fucking idiot be able to see that the circumference will increase linearly with the radius while the area increases with the square. Maybe you would like to go down your local electrical store and buy different gauges of wire, then spend more money than you need to to learn basic physics and buy a milliohm meter, or buy so much of that wire in large gauges that it actually registers some ohms on a meter.Now measure them and tell us your results.WARNING: DO NOT post in this thread again until you come back with correct results. Failure to do so will result in instant banning!

author: DavidAlfa
author_rank: Super Contributor
timestamp: August 14, 2023, 06:21:00 am
content: C'mon it's not that hard

author: Simon
author_rank: Unknown
timestamp: August 14, 2023, 06:38:36 am
content: I'm referring to his claim that resistance is proportional to circumference rather than area. No I don't want his explanation, we know it will be bollocks! He has to prove it, in real life, the hard way. That's how scientists do it when they want to defy current understanding, unless of course you just messed up in your latest discovery of a super conductor!

author: aetherist
author_rank: Frequent Contributor
timestamp: August 14, 2023, 07:30:56 am
content: Quote from: Simon on August 14, 2023, 06:14:55 amOk, i have the correct results. I got my results from the link provided by TimFox.A 1.0 mm Cu wire 1000 m long has a resistance of 35 ohmA 10.0 mm Cu wire 1000 m long has a resistance of 3.6 ohm.A 10.0 mm wire has a Xsectional area 100 times that of a 1.0 mm wire.Hence the resistance of a 10.0 mm wire should be 0.35 ohm based on Xsection area.And the resistance of a 10.0 mm wire should be 3.5 ohm based on circumference.So, my circumference theory has an "error" of 0.1 ohm.But your area theory has an error of 3.15 ohm.

author: 2N3055
author_rank: Super Contributor
timestamp: August 14, 2023, 08:37:12 am
content: Quote from: aetherist on August 14, 2023, 07:30:56 amThat table is simply wrong. Here is one that is correct:https://www.engineeringtoolbox.com/copper-aluminum-conductor-resistance-d_1877.htmlResistance scales with cross section area. That is not some stupid theory, that is proven fact. If you don't trust scientists, follow the money.Copper is sold by weight which is a cross section area x length x specific weight of copper. People would be VERY UNHAPPY with the price of cables if the current capacity was linear with diameter....

author: aetherist
author_rank: Frequent Contributor
timestamp: August 14, 2023, 12:58:46 pm
content: Quote from: 2N3055 on August 14, 2023, 08:37:12 amYes, that table says that resistance/area is constant -- for DC i suppose, solid circular.And for sure that is a problem for my elekton (photon) elekticity (hugging the surface of a wire).But i did not want to argue about elektons.I didnt even want to argue about electrons -- ie re the topic that electrons are round.I wanted to point out that there is no such thing as a hard little nutty electrons orbiting a nuclei -- i reckon that what we have is photons (elektrons) orbiting & hugging nuclei.And leave it at that. Bearing in mind that the nature of the atom & electrons has a long history of contrary ideas.

author: TimFox
author_rank: Super Contributor
timestamp: August 14, 2023, 02:04:50 pm
content: Sorry about the wrong values in the table I linked (one of many that pops up on Google).I was looking for one in straight metric units, without practical wire gauges, and did not re-calculate the values myself.Note that no one holds the "solar system" model of the atom to be appropriate any more, except graphic artists.Quantum mechanics is a difficult topic, but it is past the "hand waving" state.In atoms, spectroscopy is an advanced and accurate field of study: the early successes of quantum theory explained the spectra of light interaction with atoms.Further work in quantum electrodynamics included the incredibly accurate calculation of the Lamb Shift, which gives the "fine-structure constant" to within 1 ppm of the measured value.Since the Lamb Shift in hydrogen is a microwave frequency, it can be measured with high precision.Trigger warning: heavy mathematics.https://en.wikipedia.org/wiki/Lamb_shiftIf you want to contribute to a field where there are still unsolved questions, look at recent (g-2) measurements for the muon.

author: aetherist
author_rank: Frequent Contributor
timestamp: August 14, 2023, 02:16:19 pm
content: Quote from: TimFox on August 14, 2023, 02:04:50 pmThe atom is unsolved (but my elektrons help). Electricity is unsolved (but my elektons help). Quantum theory is a model -- & we need good models -- but models dont explain anything -- models give us numbers only.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: August 14, 2023, 02:27:52 pm
content: Quote from: aetherist on August 14, 2023, 12:40:38 amIt does -- at AC.Wait, you again? God damnit.Well, Tim has his answer at least. You were never looking for answers so it doesn't matter.Tim

author: Nominal Animal
author_rank: Super Contributor
timestamp: August 14, 2023, 03:25:19 pm
content: Quote from: 2N3055 on August 14, 2023, 08:37:12 amAgreed. And that table is easily reproduced using the simple steady-state DC conductor model, where resistance \$R\$ is a function of length \$\ell\$ and cross-sectional area \$A\$ at conductivity of \$\sigma = 58 \text{ S}/\mu\text{m} = 58 \times 10^6 \text{ S}/\text{m}\$ or equivalently resistivity \$\rho = 1/\sigma = 17 \text{ n}\Omega \cdot \text{m}\$ (for soft solid copper),$$R(\ell, A) = \frac{\ell}{\sigma A} = \frac{\ell \rho}{A}$$or for a round single-strand wire of radius \$r\$,$$R(\ell, r) = \frac{\ell}{\sigma \pi r^2} = \frac{\ell \rho}{\pi r^2}$$where the unit \$S\$ refers to siemens, \$[ \text{S} ] = [ \Omega^{-1} ]\$.One way to verify this in practice would be to measure the resistance of different shapes but constant amounts of liquid mercury. Its conductivity is only about a sixtieth of that of copper, but that just means you don't need stupid amounts of mercury or an unrealistically precise ohmmeter. You do need to control the temperature precisely, because that significantly affects the conductivity.For solids, one could use gallium, which melts at a very low temperature, but is a bit more conductive than mercury. Melt it to reshape it, then cool down to the precise measurement temperature (for example, at freezing point of water at a constant atmospheric pressure), to get each data point. An important point to remember is that even trace amounts of certain elements will significantly change the conductivity, so mixing the shapes instead of going from one extreme to the other is important to alleviate the drift in the results because of contamination.Of course, all that has already been done by many, many people, and the results are in agreement with the above model.

author: TimFox
author_rank: Super Contributor
timestamp: August 14, 2023, 03:46:43 pm
content: In lieu of a model (for systems too small or too large for direct observation) that gives quantitative results which can be compared with experiment, one could use the method used by Muppet Laboratories (on an ancient episode of The Muppet Show).https://muppet.fandom.com/wiki/The_GermSince germs are too small for humans to examine directly, instead of using a microscope to visualize the germ the lab used a drop of "germ enlarger" to increase the size of the germ to roughly human size, whereupon it decided to examine Beaker, the long-suffering lab assistant.

author: Njk
author_rank: Frequent Contributor
timestamp: August 14, 2023, 03:57:05 pm
content: Quote from: TimFox on August 13, 2023, 11:46:45 pmLet's keep in simple: because when enough time is provided, the electricity penetrates inside, to make more intimate bond with the wire.

author: TimFox
author_rank: Super Contributor
timestamp: August 14, 2023, 04:03:56 pm
content: Quote from: Njk on August 14, 2023, 03:57:05 pmEven simpler: at DC the charge carriers move through the entire cross section of the conductor.

author: gnuarm
author_rank: Super Contributor
timestamp: August 14, 2023, 04:07:09 pm
content: Quote from: TimFox on July 07, 2023, 06:42:25 pmI'm confused. How could the electron have a dipole moment? It consists of no constituent parts. It is a primitive particle. To have a dipole moment, it would need two opposite charges, separated by a distance. Is someone proposing the electron is not primitive? Or do I misunderstand what a dipole moment is?

author: TimFox
author_rank: Super Contributor
timestamp: August 14, 2023, 04:12:40 pm
content: Quote from: gnuarm on August 14, 2023, 04:07:09 pmIn the basic models, the electron’s dipole moment is zero, but more complicated models suggest a very small moment. Recent experiments are looking for a tiny moment to test these theories, which could indicate a less primitive particle. In the popular press, this was called “roundness”.When looking for very small possible effects such as this, a negative result is usually expressed as an “upper limit”: the effect must be smaller than this value.

author: Simon
author_rank: Unknown
timestamp: August 14, 2023, 04:40:43 pm
content: Quote from: aetherist on August 14, 2023, 07:30:56 amgood lord, heaven knows how I correctly worked out harness lengths in my previous career particularly when I had to calculate the length of cable required to supply a load that was more sensitive than most to voltage drop on a 24V system. I must have been on magic mushrooms at the time and was obviously helped by the fairies..... Or I used my understanding of current and correct physics.

author: vad
author_rank: Frequent Contributor
timestamp: August 14, 2023, 06:30:34 pm
content: Quote from: gnuarm on August 14, 2023, 04:07:09 pmThe currently accepted theory, known as the standard model, postulates that the electron is an elementary particle without any internal constituents. The experiment have confirmed this theory on a smaller scale than ever before.Whether the standard model is accurate, and whether elementary particles lack a geometric shape at even smaller scales is unknown. Alternative theories might surface if future experiments reveal finer structures within elementary particles.Physics differs from climate “science”. In physics, room for doubt exists, and there are always alternative theories. Experimental physicists always try to find anomalies that cannot be explained by theories.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: August 14, 2023, 06:53:21 pm
content: Quote from: Simon on August 14, 2023, 06:14:55 amSo.... we're waitingTim

author: SiliconWizard
author_rank: Super Contributor
timestamp: August 14, 2023, 07:26:56 pm
content: Damn, I woke the beast!Entertaining though.

author: BILLPOD
author_rank: Frequent Contributor
timestamp: August 14, 2023, 07:39:36 pm
content: Quote from: Stray Electron on July 07, 2023, 05:19:37 pm

author: aetherist
author_rank: Frequent Contributor
timestamp: August 14, 2023, 11:06:53 pm
content: Quote from: Njk on August 14, 2023, 03:57:05 pmYes, i like that. U of course are referring to the standard AC explanation, & i suspect that Tim's original linked table is for AC.But i am liking your explanation in regard to my hugging elekton elekticity. Bearing in mind that i agree that there is an electron electricity in a wire (which i describe as hugging elektron elektricity)(here hugging the nuclei).But i did not intend to say any more re my hugging elektons. But then i saw your comment which is in line with my thinking, that (fast) elekton elekticity is "when enough time is provided" "penetrates inside" to give us (slow) elektricity.And, re other comments re the correctness of present engineering equations etc, i am happy with present equations, my ideas dont change any of that.But, our present equations are simply simple models, that give good numbers -- they dont explain anything.

author: aetherist
author_rank: Frequent Contributor
timestamp: August 14, 2023, 11:15:11 pm
content: Quote from: vad on August 14, 2023, 06:30:34 pmIts simple. All is photons, the elementary quasi particle.Photons make elementary particles.But, in an atom, we dont have elementary particles orbiting a nucleus -- we have photons orbiting the nucleus.Photons have mass. Photons have momentum. Photons have inertia. And so do orbiting photons in an atom.And, orbiting photons have all of the qualities of the (silly) orbiting electrons.

author: TimFox
author_rank: Super Contributor
timestamp: August 14, 2023, 11:32:32 pm
content: How do the orbiting photons in your model (not yet substantiated) explain the Zeeman and Stark effects of external magnetic and electric fields on the atomic spectra?(BTW, I haven't done the calculations yet but I guess that the erroneous wire table I linked was in terms of mm2, the common wire size in metric-speaking countries, rather than mm diameter, since I have had technical conversations with foreign engineers who used "mils" or "mm" as an abbreviation for area.)

author: aetherist
author_rank: Frequent Contributor
timestamp: August 15, 2023, 12:01:11 am
content: Quote from: TimFox on August 14, 2023, 11:32:32 pmI am an Engineer not a physicist, & i dont know enuff about that kind of stuff.I go along with most of what physicist JG Williamson says -- he says that photons orbit a nucleus.A hugging photon has charge & orbit etc etc, like a (silly) electron. Hence i dont see how orbiting photons should have any special problem (compared to silly electrons).Light is photons confined in one dimension -- no nett charge (in the far field).Elekticity is photons confined in two dimensions -- have negative charge.Elektrons is photons confined in three dimensions -- have negative charge.

author: vad
author_rank: Frequent Contributor
timestamp: August 15, 2023, 01:06:01 am
content: Quote from: aetherist on August 14, 2023, 11:15:11 pmNay, atoms are made of cheese. Lighter atoms are made of fresh, unprocessed varieties, such as ricotta. Atoms of heavier elements up until iron are made of stretched curd varieties, such as mozzarella. The heaviest atoms are made of Swiss-type cheese.

author: gnuarm
author_rank: Super Contributor
timestamp: August 15, 2023, 02:45:12 am
content: Quote from: Simon on August 14, 2023, 04:40:43 pmI once worked at a place where there were rumors of a guy who not only was stupid, but had no idea just how stupid he was. This was a beltway bandit, where we would either build systems for the government, or sometimes simply provide direct support.The story of this guy goes that he was in a meeting where they were picking the location of new antennas to be installed. Different people gave a few opinions. Then this guy, we'll call him Floyd, chimes in that we should put the antenna at the bottom of the hill. Everyone had a laugh, then Floyd continued. He said the antenna should be a the bottom of the hill, so that they would collect the electrons as they ran down the hill. Another good laugh. But, Floyd wasn't laughing! He was being serious!Another time, Floyd and some other guys were doing a facility survey to prepare for installation of equipment in a room. It's basically measuring the space, making sure there was enough AC, electricity, etc. One of the team members was calculating the floor area, length times width. Floyd said he was doing it wrong. It's length divided by width. The guy asked him what he was talking about. Floyd's reasoning was, "How many quarters in a dollar? How many quarters in two dollars? See?"It's hard to argue with someone like that.

author: TimFox
author_rank: Super Contributor
timestamp: August 15, 2023, 02:48:39 am
content: It's like playing chess with a pigeon: First, he flaps his wings and knocks over the pieces, then he takes a dump on the board, finally he flies home and brags that he won the game.

author: EPAIII
author_rank: Super Contributor
timestamp: August 15, 2023, 09:08:41 am
content: Actually, since electrons are best described by quantum theory which uses what is called a wave function that describes the probability of finding any individual electron at any given point in the universe and since that implies that each individual electron can actually and truly be at any given point in the universe when that wave function is made to collapse, then the shape of an electron, if it can indeed be said to have any shape at all, would be the shape of the universe itself.And since we don't actually know what the shape of the universe itself is, we do not know what the shape of an electron is. Not really!

author: Nominal Animal
author_rank: Super Contributor
timestamp: August 15, 2023, 10:52:30 am
content: Quote from: TimFox on August 14, 2023, 11:32:32 pmIt matches the \$R(\ell, A) = \ell \rho / A\$ exactly, when "gauge" is area in square millimeters, \$\ell\$ is length in meters, and resistivity were \$\rho = 35.2 \text{ n}\Omega \cdot m\$.It seems the table has several errors, not just using "gauge" and "mm" for cross-sectional area. For example, the resistivity of copper is around \$\rho = 17 \text{ n}\Omega \cdot m\$ (depends on the copper alloy and structure, hardened/non-annealed copper tends to have a slightly higher resistivity/lower conductivity), so it looks like the author erroneously halved the area, as in "\$A = \pi r^2 / 2\$" –– which is a common error when confusing radius and diameter \$D = 2 r\$ and thus \$A = \pi r^2 = \pi (D/2)^2 = \pi D^2/4\$.Understandable errors, but horribly annoying when taken as correct. I, too, were bamboozled for a second, before I checked some of the stated resistances (which obviously did not match the known correct and measured values). And the edits to this post were because I was again bamboozled when investigating how the factor of 2 error came to be.

author: Psi
author_rank: Super Contributor
timestamp: August 15, 2023, 11:10:35 am
content: This seems relevant.

author: Nominal Animal
author_rank: Super Contributor
timestamp: August 15, 2023, 11:35:09 am
content: I'm sad, because there are no Pallas cats inPallas, Finland. None at nearby Ylläs, either.I will now get my coat (it's still hanging at the bar), and go ask ifI can has Cheezburger.

author: Simon
author_rank: Unknown
timestamp: August 15, 2023, 11:55:34 am
content: Quote from: aetherist on August 15, 2023, 12:01:11 amOK, so we are done, you say you don't know what you are talking about but keep talking....

author: Simon
author_rank: Unknown
timestamp: August 15, 2023, 11:57:08 am
content: Quote from: gnuarm on August 15, 2023, 02:45:12 amPoint taken,

author: gnuarm
author_rank: Super Contributor
timestamp: August 15, 2023, 01:13:10 pm
content: Quote from: EPAIII on August 15, 2023, 09:08:41 amMaybe I missed an important post somewhere, but my understanding is an electron is a fundamental particle. That means it can have no structure. How would it have any shape, other than a point?If you wanted, I suppose you could make an argument that it's an infinitesimally small sphere. But as soon as you do that, you could extrapolate it to be shaped like a chair or anything else.What's wrong with just saying it's a point with no particular shape? Did someone already mention this?

author: gnuarm
author_rank: Super Contributor
timestamp: August 15, 2023, 01:16:39 pm
content: Quote from: Simon on August 15, 2023, 11:55:34 amThat's very rude. He is saying that he doesn't understand all the details, but he believes what he reads of what others say about the subject. Is that ok with you?

author: radiolistener
author_rank: Super Contributor
timestamp: August 15, 2023, 01:17:09 pm
content: Quote from: TimFox on August 14, 2023, 11:32:32 pmcross section area in mm2is commonly used for high power electricity, such as mains lines, power cable between mains socket and high power equipment, etc. When you deal with more precise electronics, for example hand made RF inductors, transformers, in these area diameter in mm is commonly used...For example bobbins with copper wire for inductors and transformers are marked with mm diameter. I don't remember bobbins which was marked with cross sectional area in mm^2.

author: gnuarm
author_rank: Super Contributor
timestamp: August 15, 2023, 01:39:36 pm
content: Quote from: radiolistener on August 15, 2023, 01:17:09 pmI can't recall specifics, but when I look for info on wires, I seem to recall the use of terms which are not properly electronic. It's as if the electrical world tossed out all the info on units and just invented their own. So, I think there is a unit they use for area, which reads like a linear unit, circular mils, perhaps? This gets shorted to just mils in tables. Maybe that's also true for mm?

author: TimFox
author_rank: Super Contributor
timestamp: August 15, 2023, 01:50:02 pm
content: Quote from: gnuarm on August 15, 2023, 01:13:10 pmYes, the usual understanding is that the electron is a fundamental particle with no structure.The experiment discussed in the ill-titled article is testing that understanding, and reported an upper bound to the dipole moment, meaning that they found zero moment (as expected) and that their experiment could be quantified by that bound.

author: TimFox
author_rank: Super Contributor
timestamp: August 15, 2023, 01:52:22 pm
content: Quote from: radiolistener on August 15, 2023, 01:17:09 pmFrom a table posted by a wire manufacturer: "The most common method of referring to conductor sizes uses the cross-sectional area, expressed in mm². The following AWG metric conversion table converts AWG to mm and inches, and also lists the cross sectional area (mm2)."https://www.elandcables.com/the-cable-lab/faqs/faq-what-is-the-conversion-between-awg-and-the-metric-system

author: TimFox
author_rank: Super Contributor
timestamp: August 15, 2023, 03:44:14 pm
content: Quote from: gnuarm on August 15, 2023, 01:39:36 pmAn American conventional unit (inch based) for wires is the "circular mil", which is defined as the area of a circle that is one mil in diameter, where one mil = 0.001 inch.It is often found in design rules or rules-of-thumb for recommended current density in transformer windings, etc., in amperes per circular mil.The American "AWG" gauges for wires, typical for "gauges", is a logarithmic measurement rather than linear measurement, where a difference of 3 in AWG is close to a factor of 2 in area: AWG 20 is 1,022 cir mil and AWG 17 is 2,048 cir mil in area.My mnemonic is that AWG 10 is 0.1019 inch diameter, close to 1/10 inch.For very large wires, larger than AWG 0 (sometimes called 1/0) = 0.3249 inch diameter or 106,000 cir mil area, the conventional series proceeds to multiple 0's: 00 (2/0), 000 (3/0), and 0000 (4/0).Thereafter the amusing abbreviation "MCM" for "thousand circular mils" (as in the ancient Roman numeral M = 1000, not the modern mega).I first ran into this when observing the installation of a new electrical box fed by "250 MCM" wire (0.5 inch diameter), the next size up from AWG 0000 at only 212,000 cir mil area.Now, the skin depth of copper at 60 Hz is approximately 8.5 mm = 0.335 inch (depending on alloy), so one reaches diminishing returns in AC resistance per price of copper for solid copper wires above that diameter.I believe that the maximum copper wire diameter in that series is 2000 MCM (1.414 in = 36 mm diameter).

author: AVGresponding
author_rank: Super Contributor
timestamp: August 15, 2023, 04:48:22 pm
content: There's a certain laziness in referring to the size of cables in mm2by just using "mils". I have to confess I am sometimes guilty, as are all my colleagues, from time to time...

author: TimFox
author_rank: Super Contributor
timestamp: August 15, 2023, 05:47:59 pm
content: Quote from: AVGresponding on August 15, 2023, 04:48:22 pmAs I have mentioned elsewhere, I fell into a technical misunderstanding when a UK engineer asked me if "4 mil" wire were adequate for a power connection, and I thought he meant 4 mm diameter instead of 4 mm2.I did a rough calculation based on my mnemonic that AWG 10 was 0.1 inch diameter, knowing that the current rating of AWG 10 is 30 A.edit: corrected typo

author: radiolistener
author_rank: Super Contributor
timestamp: August 15, 2023, 06:57:02 pm
content: Quote from: TimFox on August 15, 2023, 01:50:02 pmin reality no one knows what is electron and if it exists at all, we just using different physics models that can predict behavior in some cases, but there is no model which explains all details about electron. Some models represents electron as particle, some model represents it as wave, but we don't know what is it exactly

author: TimFox
author_rank: Super Contributor
timestamp: August 15, 2023, 07:24:24 pm
content: I have had experience with electrons in vacuum (CRTs, particle accelerators, vacuum tubes, radioactive beta decay) and know that they exist.In my view of physics, "particle" and "wave" are mathematical descriptions of the behavior of entities, analogous to billiard balls and ocean waves in much larger macroscopic contexts, that quantum mechanics' rules dictate how to calculate their properties and motion.Note that "model" and "theory" are not bad things (like in the vulgar usage "just a theory") in science.In this particular discussion, the experiment is testing models that assume no structure (zero moment).In another recent experiment, measurement of (g-2) in muons (heavier leptons with short lifetime) tests if the currently accepted "standard" model accurately models the interaction of the muon with a host of other particles (real and virtual) buzzing around it.

author: Wallace Gasiewicz
author_rank: Super Contributor
timestamp: August 15, 2023, 09:41:42 pm
content: I think we need to be more sensitive about the issue. Do electrons perceive themselves as "round"?? Is this a deprecatory appellation?? We need to let the electrons self identify as what they choose to be and not be so judgemental.What about the electrons in "transition"?? How should we address them?? Trans electrons do important work in things like LEDs.We should be more aware of their personal identity and not just call them what we think they are.