Talk:Elementary charge

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Comments by WFPM[edit]

If the two fundamental entities existing in the universe are energy and matter, and they are both positive entities, and if an elementary charge is capable of motivating a physical activity of these entities; then how is it that say two negative electrical charges can first change a one charge positive energy activity in one direction into a condition of nonactivity and then secondly into a one charge positive energy activity in the opposite direction?WFPM (talk) 18:28, 17 February 2010 (UTC)

The Milliken and other experiments established that a small particle such as an oil drop could be experimentally determined to have a measurable quantity of reactivity to counteracting gravity and electrostatic force fields that could be quantitatively determined to be proportional to a value of e/m, where the e value is the reactivity to the electrostatic field and the m value is the reactivity to the gravitational force field. This could be refined to include the monitoring of a constant m value particle in an en electrostatic field and determining the minimum incremental values of the electrostatic e value that were noted to occur to the experimental oil drop. These experiments resulted in the establishment of a minimum incremental electrostatic charge value that could occur to a drop, which was assumed to be that contained by a particle named the electron.

So if a particle is falling and acquiring energy from the gravitational field, it can be slowed and even stopped and reversed by an increase in the electrostatic field? But in that case the electrostatic field would have to be the supplier of the energy to the particle. So the e value of the electrostatic field has to be associated with a source of energy sufficient to power the counteracting field.WFPM (talk) 20:46, 17 February 2010 (UTC)

There is no theory on this page, is there even any theory? It would be good to say here if the whole thing is unexplained. I think there's something about the existence of even a single monopole implying quantisation of charge. Maybe the fact that irreps of U(1) can only have integer 'charge' is relevant, I dunno. —Preceding unsigned comment added by (talk) 15:17, 10 October 2010 (UTC)


Elementary charge
Definition: Charge of a proton
Symbol: e
Value in Coulombs:     1.602176487(40)×10-19 C
Elementary charge
Unit system SI, natural units
Unit of electric charge
Symbol e 
Unit conversions
1 e in ... ... is equal to ...
   coulomb    1.602176487(40)-19
   statcoulomb    4.80320427(12)-10

I believe that my box (top) has more relevant information, is more concise, and most importantly is much much easier for a reader to understand. (Entries like "standard", "quantity", "1 e =", etc. are confusing, I had to read the template multiple times to understand what was going on, and I'm an expert.) Sure, it's nice to have a similar and consistent infobox in multiple articles, but it's not a crucial priority. What is a crucial priority is having articles that present information as clearly and successfully as possible. Therefore we should judge the boxes on their own merits, and not automatically prefer the second one because it follows a previously-existing template while the first one does not.

See WP:Disinfobox for a bitter and cynical take on this topic. :-) --Steve (talk) 22:01, 25 October 2010 (UTC)

While I agree that the "official" box is confusing, I have to say that your box here is not much better:

  • it should state somewhere that it is a unit info box
  • unit symbols are not in italic, only quantities are
  • it does not mention the system of units it belongs to
  • it does not mention what "kind of quantity" it is used for
  • it could mention if it is a base unit or a derived unit
  • it should recognize that some units are used in several systems of units
  • it seems to be a "fundamental constant infobox" rather than a "unit infobox"

For those reasons I suggest that 1) we have both infoboxes, since e is both, a fundamental constant as well as a unit, 2) you continue your work on a better "official" unit infobox. I do think it would be useful to have consistent unit infoboxes. Kehrli (talk) 21:38, 26 October 2010 (UTC)

OK I should clarify: My proposal is not a "unit infobox", it's a "just plain infobox" intended for the top of the article. :-) I suppose it's OK to also have a "unit infobox" somewhere in the article, but I think the box should be labeled at the top: e as a unit of charge. Otherwise people would naturally assume it's a box about e in general, e the physical constant.
I don't think it's actually necessary to have a "unit infobox" at all, but I'm not really opposed as long as the title is changed. I'm putting it in for now... :-) --Steve (talk) 22:33, 26 October 2010 (UTC)
Again, I agree with you on most accounts. A unit infobox should definitely be labeled as such. I also think that the property fundamental constant is more important that the property unit. I still think that it might be useful to have a standardized infobox for units. This will increase the consistency of Wikipedia and will also assure that the terminology is in line with official metrology standards. Unfortunately the current unit infobox does a poor job in this respect. Kehrli (talk) 08:39, 27 October 2010 (UTC)

different values for the elementary charge!!![edit]

There seem to be different values. Only the last 3 digits differ: The article about Coulomb, the alternative infobox on the talk page and my calculator say, that the elementary charge is My formula sheet, and the current wikipedia article say its . And my stupid textbook says which is just plain dumb ...

Elementary Charge, Absolute Value of Electron Charge[edit]

It is not correct when this page says that the elementary charge is defined as the charge of a proton. It is defined as the absolute value of the electron charge. The absolute value of electron charge is equal to the charge of a proton, however that is not how it is defined, and possibly in the future when more accurate measurements are made the absolute value of electron charge may end up being slightly different to the proton charge, and then it would not be equal to it. — Preceding unsigned comment added by (talk) 11:26, 16 January 2014 (UTC)

Sometimes "q" instead of "e"[edit]

The symbol is sometimes "q" instead of "e". See Boltzmann_constant#Role_in_semiconductor_physics:_the_thermal_voltage. This should be mentioned. Andries (talk) 12:06, 20 April 2014 (UTC)

SI to adopt Elementary Charge as determining Ampere[edit]

In 2018, the SI org CIPM is planning to discard the ampere-balance, and instead use Quantity of Electricity (in the form of the elementary charge,) to determine the Ampere. Be prepared to add a bit about this in a couple years. — Preceding unsigned comment added by (talk) 22:45, 22 May 2016 (UTC)

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What on earth is HEP meant to mean? Even Google doesn't know, and wiki doesn't ... The given value 0.30282212088 happens to be and not merely this is a real tragedy ... Thus the 1 HEP C. Right? Ra-raisch (talk) 21:07, 12 August 2017 (UTC)

HEP is High energy physics, or particle physics the field that relies on quantum field theory where rationalized Lorentz–Heaviside units are used, in their naturalized form. Charge is not an independent dimension, as in Gaussian cgs units, so ε0=1; and if you did not wish to naturalize the units, use plain ones, as here. In most of the world of particle physics, these are the units used on account of their simplicity, elegance, and, you guessed it!, naturalness. If you wish, I could add a link to Lorentz-Heaviside, but please do not perpetrate plain wrong formulas in WP, which will only end up confusing more readers with inconsistencies and absurdities. Cuzkatzimhut (talk) 23:35, 12 August 2017 (UTC)
@Cuzkatzimhut: ok, I think a link to High-energy physics would be more appropriate. The dimension should be given with 1. Since most readers won't be familiar with HEP or LH-cgs, there should be more respect for SI, I am not bothered about non-metric systems popular in the US and UK. Most pages comparing or explaining the unit systems are grotty in this respect, lacking conversion tables, leaving constants . CODATA is a paragon and guideline in this respect. In this case here, the conversion factors MeV and fm are missing in the given unit: √ℏc/MeVfm) Ra-raisch (talk) 09:49, 13 August 2017 (UTC)
but even calculating and not the given value of 0.30282212088. I see no way of leaving ε0 without introducing Z, RK or other constants. Ra-raisch (talk) 10:36, 13 August 2017 (UTC)
I'm sorry, but you appear to be having a philosophical problem with Lorentz-Heaviside units, or cgs ones, and this is not a forum. Perhaps talking to a physicist in person, or reading up on HEP might help. As stated repeatedly, the elementary charge is a dependent quantity, defined as in absolutely any units for ħc you may prefer. It is not in the units. Units are all interconvertible. HEP physicists, for 3/4 of a century, have been choosing to keep ħc in mind and insert it in the final answers handed over to engineers at the last moment. It is not rocket science. Please do not insert wrong formulas in the articles.Cuzkatzimhut (talk) 13:40, 13 August 2017 (UTC)
Well I don't like it that's true, but that is not the point. Your conversion is not(!) SI. No hidden factors bearing in mind! √4παℏc) = 5.3843840002589234e-14 m√N whereas e = 1.6021766208e-19 C. I think your rocket would miss the mars by wrong direction, dealing with manufacturers calculating in SI. And that is the guilty of the scientist not the manufacturer's. And as I said, wiki is not a platform of scientists but of ordinary people, using everyday language, measures and understanding. I found the correct conversion but you didn't like it: C. (ℏ=1.054571800e-34 Js, ε=8.85418781762039e-12 F/m).
C and in SI and not merely √ℏc) = 1.7780682553250995e-13 m√N. So using √ℏc) may be correct in HEP but not in SI. Ra-raisch (talk) 15:03, 13 August 2017 (UTC)
The Vacuum permittivity ε0 is necessary in all conversions to Coulombs, and perhaps you wish to devote your energies in that article. HEP physicists think of it as part of the definition of the Coulomb, in essence. If you convert to Coulombs squared, of course you will need it. But that is the beauty of the L-H system, that it never has to consider these conversions. It ends up measuring energies, times, momenta, etc... units linked to Newtons, Joules, seconds, etc... if you wished to talk to an engineer. Perhaps at the heart of this misunderstanding is the misplaced expectation that particle scattering will result in quantities involving Coulombs, as opposed to energies, angles, times... You never have to go there. I don't see why a layman would wish to go there, as some part of a notional fantasy, rockets and all. Cuzkatzimhut (talk) 16:37, 13 August 2017 (UTC)
I did not invent the equation g=e/sw, it is ridiculous in my eyes since g does not react with e. But the conversion of units is a completely different question. At least we agree at last, that ε must not be neglected in the conversion. That is all I said from the beginning, this was exactly what I requested, nothing more! ... so probably g=e/sw is to be understood by converting e(SI) to e(HEP) and taking g as a unit by itself. But how can these be compared by sw ... ok that is leading somewhere else. Ra-raisch (talk) 18:03, 13 August 2017 (UTC)
We only agree that ε must never be neglected in the conversion to Coulombs, part of whose definition it really is, but this is a conversion that I explained is not needed and has little point to it. By contrast, the standard picture involves SI units, Newtons, meters, ... that are used in their MeV, fm avatars. Indeed, g is the mother of all quantities, and, e is a derived quantity; this is at the heart of Electroweak unification: this is what we now know, but we did not in 1966 .. it suddenly all made sense, at last... Cuzkatzimhut (talk) 18:47, 13 August 2017 (UTC)
good, back to the article: 1) I understood now that √ℏc) is just the equation used in HEP in place of a unit and not to be taken for a conversion to/from SI. I guess this is confusing for anybody not familiar with HEP. I am not sure though how to clearify this in the expression, but may-be like this: √ℏc)[HEP]. 2) A little more explanations could/should be given in the page of HEP. 3) On the now linked page (LH-units), HEP is not mentioned at all. Ra-raisch (talk) 19:59, 13 August 2017 (UTC)
OK, I did something for a start. Your point that they had to be showcased up front in the L-H article is a good one. (Personally, I believe the string theory sentence there is correct but pompously silly--I would not object to it disappearing.) Here, my gut reaction is precisely to prevent going through metrology and systems of units, etc... The point of the box is to give the reader a quick tablet of reliable facts. Cuzkatzimhut (talk) 20:28, 13 August 2017 (UTC)
beautiful Ra-raisch (talk) 21:50, 13 August 2017 (UTC)