Talk:Electric charge

To do:

Charge and Noether's theorem, gauge theories.

Please repair the History section due to vandalization (I'm not familiar enough with Wiki to do this myself right now). —Preceding unsigned comment added by 74.11.107.246 (talk) 00:03, 10 March 2009 (UTC)

There is an inconsistency beetween the introduction who say "Electric charge comes in two types, called positive and negative" and "There is only one kind of electrical charge, and only one variable is required to keep track of the amount of charge" which come later(in Electrification by friction). —Preceding unsigned comment added by 129.241.164.154 (talk) 12:22, 4 February 2011 (UTC)

I'm not sure if this has been actioned but the introduction still says there are two types of electric charge. Surely there is only one type of charge and a anti-charge, charge is from the U(1) part of the Standard Model so don't see how it can have two.Dja1979 (talk) 01:25, 4 November 2012 (UTC)

It is just an attempt to use very simple language, because people reading the article might have no idea what charge or electricity is. If you can think of a better wording, feel free to change it. :-)

I don't suggest using the word "anti-charge" in the second sentence ... I think it would sound like nonsense to a non-physicist. But I'm sure you can think of other wording too. :-) --Steve (talk) 13:12, 4 November 2012 (UTC)

I think the sentence There exist two types of electric charges, called positive and negative. could be replaced by An object can be either positively or negatively charged. or Charge can be either positive or negative.. Ulflund (talk) 13:25, 4 November 2012 (UTC)

Personally I like Charge can be either positive or negative. As an object can neutral as well as positively or negatively charged.Dja1979 (talk) 13:38, 4 November 2012 (UTC)

removed

I removed this also, since amperes are based on coulombs, not the other way around: - Omegatron

One coulomb (6.24 x 10¹⁸ charge carriers) can be defined as the quantity of charge that has passed through the cross-section of a Conductor (material)|conductor carrying one ampere within one second.

Actually no. Last time I checked, the Ampere is considered the fundamental unit, the A in MKSA, with the coulomb being an Ampere-second. -- Decumanus | Talk 22:38, 30 Mar 2004 (UTC)

Hmm... But the coulomb is a specific number of elementary charges, which are certainly a fundamental unit... I guess this needs to be explained, regardless. - Omegatron

You're right. sorry. - Omegatron

No prob. It's certainly counterintuitive in some sense. -- Decumanus | Talk 22:52, 30 Mar 2004 (UTC)

Confusion: the NIST uses the word "fundamental" in an odd way. Certainly the Coulomb is the more fundamental concept, since an Ampere is a *flow* of a certain number of Coulombs per second (you can't have coulombs-per-second without coulombs!) But in NIST terms, "fundamental" refers to a primary, directly-measured calibration standard, versus "derived" standards which are not measured directly. At one time the Coulomb was the "fundamental" standard. IIRC, the Coulomb was measured as a deposition of a certain amount of silver in an electrochemical cell. But Amperes are far easier to measure accurately by measuring the magnetic force between adjacent parallel conductors. So today, the electric current is the "fundamental" standard, and the standard for charge is then derived from the high-precision standard Ampere, rather than being measured directly. - --Wjbeaty 06:28, Feb 17, 2005 (UTC)

Note that since 2019 redefinition of the SI base units the coulomb is defined, and ampere derived from it. Also, the second and speed of light are defined, with the meter derived from them. However, according to the BIPM, meter and ampere are still base units, while coulomb and velocity are derived units. Somehow derived doesn't have the usual meaning. Gah4 (talk) 13:28, 8 December 2021 (UTC)

Removed for confusion

"Before that experiment, charge was ordered in anion at cation, a term introduced by Michael Faraday."

---

Removed for confusion and incompleteness

== Conservation of Charge and Gauge invariance ==A force is said to be conservativ if work done by the force between two point is indep endent of path followed Since the action (what action? perhaps this should be a link to a rare definition of 'action'?) is invariant under gauge transformations (due to the masslessness of the photon), by Noether's theorem the (something) is a conserved quantity associated with it (with what?). Since the langrangian density is

${\mathcal {L}}=-{\frac {1}{4}}{\mathcal {F}}^{ij}{\mathcal {F}}_{ij}+A_{i}J^{i}$

plus other terms that do not involve the electromagnetic interaction, (something). since the contribution to the action by the first term is trivially gauge invariant, we need consider only the second. Under a gauge transformation A_i->A_i+∂_iφ the action is increased by

$\int d^{4}xJ^{\mu }\partial _{\nu }\phi =-\int d^{4}x\phi \partial _{\mu }J^{\mu }$

the only way for this to be satisfied for arbitary φ is if ∂_μJ^μ=0, which is the continuity equation

---

Homework question

anon comment:

Please can someone quickly and briefly explain how you create similar charges for two objects to repel (physically/practically rather than theoretically) Thank you in anticipation, a GCSE student

Try looking at the 'experiments with an electroscope' paragraphs on the Electrometer page.

--Light current 23:23, 9 February 2006 (UTC)

try rubbing glass rod with fur hardly — Preceding unsigned comment added by 49.249.251.101 (talk) 09:42, 6 April 2015 (UTC)

What kind of variable is Q

"Q is a measurement of the charge held by an object."

Q isn't a constant or a unit, and isn't used in an equation on this page. Is this equivalent to saying "l is a measurement of the length of an object"? - Omegatron 00:23, May 31, 2005 (UTC)

Quantized??

What does quantized mean? I keep running into and stumbling over this word!

It means something that isn't continuous in nature but rather, comes in small, discrete packets (quanta). For example, electric charge travels in the form of electrons, protons, etc. and they are individual units; you can't have "half the charge of an electron" or "an eighth of the charge of an electron"; it's either the whole charge or nothing. Such things that come in discrete little bundles are said to be quantized (as in quantities). At the super-ultra-microscopic level, most things are quantized and not continuous. It's only in our macroscopic world that they seem to be continuous because the quanta are so small.

See Quantum mechanics for much, much more.

By the way, you can "sign" your talk postings by including four tildes (~~~~) at the end of your posting. When you press "Save page", the tildes will be converted into your username (or IP address) in a handy Wikilinked format. A timestamp of your edit will also be included.

Atlant 18:12, 14 February 2006 (UTC)

But quarks have 1/3 and 2/3 of the charge of an electron. Maybe something should be mentioned about this.

GoldenBoar 18:11, 6 May 2006 (UTC)

It already is. Have another look at the article. --Heron 21:21, 6 May 2006 (UTC)

more details about the experiment

"This property has been experimentally verified by showing that the charge of one helium nucleus (two protons and two neutrons bound together in a nucleus and moving around at incredible speeds) is the same as two deuterium nuclei (one proton and one neutron bound together, but moving much more slowly than they would if they were in a helium nucleus)."

Which experiment was this? How is it done? - Omegatron 00:26, May 31, 2005 (UTC)

different kinds of discharge

See Talk:Spark_gap#Clarify the difference for some questions I have about the different kinds of discharge. - Omegatron 18:12, Jun 4, 2005 (UTC)

electric charge density

Could someone explain " electric charge density"? Thanks. JDR

It's the quantity of electric charge per unit volume. Units: C/m³. --Heron 14:19, 25 September 2005 (UTC)

Laymen Question

This is a very basic laymen's question. When discussing an electric charge, such as current that travels from a battery to say a light bulb, I have read in general that there is a flow of electrons. Electrons from where? For instance in chemical reactions one can determine from the reaction where the electrons traveled to and from.

Within a given current, where are these electrons coming from?

Thanks, BT

1. Yes, in metals there is a flow of electrons. Keep in mind that in other materials different charged objects can flow, like ions in salt water.
2. The electrons aren't coming from anywhere. They're already there in the metal. The current source is just pushing them in one direction. Think of wires as pipes already filled with water, and you are connecting a pump in a loop of such pipe, pushing the water in a circle. Does that help? — Omegatron 18:23, 9 October 2005 (UTC)

Free and bound charges

Could free and bound charges be added to this article? I'd do it, if I could find better references than I have online. -- Kjkolb 12:15, 26 November 2005 (UTC)

I agree. I'm specifically interested in the "free electric charge density" refered to in gauss's law. Does "free" mean that it doesn't have a corresponding positive charge to neutralize it? It would be very good if this article had a section on both electric charge density and free electric charge - also noting the variable ρ ( rho - free electric charge density) and what it means. Fresheneesz 22:46, 9 February 2006 (UTC)

wow. Looking online for free electric charge density returns links to every freaking copy of the same definition of gauss's law... Everyone a plagiarist... Fresheneesz 22:52, 9 February 2006 (UTC)

Hi guys, I added a sentence about these. For more details follow the links to "Polarization density". Yevgeny Kats 23:06, 9 February 2006 (UTC)

simple definition?

I think it would be nice if at the top of the page, before you got into all of the confusing terms, you had a simpler definition, or at least an example. Because this article is so well written that it is useless to people like me who have no idea what a subatomic particle, ore anything else on the page, is.

Does the history section not answer yor questions in simple language?--Light current 21:58, 19 March 2006 (UTC)

Nowhere in the article does it say what an electrical charge actually *is*, rather it just says how it acts. For instance, a positron is an antimatter version of the electron. It has a "negative charge" but is otherwise identical. So what EXACTLY is different? If neither particle ever came close to another particle to interact with, how would they actually differ? What is the fundamental "thing" that is a charge, in isolation from all interactions and properties? What makes a charge interact, when it does?

The first sentence says it is a property of matter. That is what it is. That is all it is. Constant314 (talk) 01:04, 6 July 2022 (UTC)

What causes it? Since matter did not exist in the early universe, nor did charge, therefore. How did charge get created from energy? 185.13.50.183 (talk) 10:22, 10 May 2024 (UTC)

Unknown. Constant314 (talk) 17:18, 10 May 2024 (UTC)

I suppose we could have a short section about Baryogenesis and Leptogenesis, the origin of charge in models of the early universe. Finding good sources may be difficult. Johnjbarton (talk) 17:39, 10 May 2024 (UTC)

Probably to hypothetical for this article. Maybe add those terms to see also.Constant314 (talk) 18:08, 10 May 2024 (UTC)

My Suggestion for an article

For [1], I suggest that adding some brief deriviation on it.

For instance:

${\mathcal {\,}}I_{output}=-{\frac {dQ_{in}}{dt}}\,$

${\mathcal {\,}}{\vec {J}}\cdot {\vec {dS}}=-{\frac {dQ}{dt}}\,$

${\mathcal {\,}}{\vec {J}}\cdot {\vec {dS}}=-{\frac {\partial {\rho }}{\partial {t}}}{d\tau }\,$

${\mathcal {\,}}\int _{s}{\vec {J}}\cdot {\vec {dS}}=\int _{\tau }-{\frac {\partial {\rho }}{\partial {t}}}{d\tau }\,$

${\mathcal {\,}}\int \int \int \nabla \cdot {\vec {J}}\,d\tau \,=\int \int \int -{\frac {\partial {\rho }}{\partial {t}}}{d\tau }\,$

${\mathcal {\,}}\nabla \cdot {\vec {J}}+{\frac {\partial {\rho }}{\partial {t}}}=0\,$

Charge migration

The section about two types of charge is a little confusing. There is no positive flow per se, it is simply the illusion created by the counter flow of electron vacancies. This section seems somewhat unwieldy User A1 04:35, 9 January 2007 (UTC)

James bond and the symbol q

Hello,

I have reverted the assertion that the symbol Q is related to the character from James bond, a quick search of some journals turns up articles using the symbols that clearly predate the fictional character I will assume at this point that you have simply made this assertion in error, but any further additions along this line may involve further action against your user. Thankyou User A1 05:23, 1 February 2007 (UTC)

1. You did not cite a single source, journal, topic, or person being addressed.
2. where is at least a quotation or exerpt of your selected topic.
3. Q, is #Quanta. it might be a unit of #Watts.
4. Quantum is two things, Photon and\or Hidden StJerome Topic.

Ui Neil Mahmuod Elmontaser Cidi Almasri Sandage (talk) 11:44, 26 April 2020 (UTC)

Removal of NPOV tag

Hello,

I removed the NPOV tag, as i did not believe that there is any reason for it. If anyone can tell me what the reason was for adding it, please comment. Thanks User A1 04:52, 22 February 2007 (UTC)

Expansion.

Of itself this article is satisfactory, it is only when one reads other articles about the manifestations of electric charge, e.g. displacement current, that one sees the need for a more powerful illumination. I suggest expansion along the following lines.

Charge is a property of fundamental particles only; there are charge-like manifestations e.g. electron holes and ions; they only approximate fundamental charged particles, they are composites.

The term particle is too restrictive. A charged particle comprises its mass and its charge, it is characterised by an electric field that is infinite in extent. If this is appreciated the wave/particle dual nature of an electron is more easily understood; it is easier to understand why electrons passing through adjacent slits interfere with each other, even more so when one remembers that the moving charge generates a magnetic field.

The total charge of a particle is determined by integrating the electric field over any surface that encloses it only, however big. Looked at this way one may consider an electron as being infinitely big! It becomes much clearer why displacement current is the effect produced by a moving charge. May I say that, if the surface integration is changed so that a charge is included that was previously excluded, that charge flow has taken place, and that the corresponding current flow could be vanishingly small?Excitation 20:25, 24 February 2007 (UTC)

several types of electricity

I deleted the line "Matter is actually composed of several kinds of electricity", since it really doesn't make sense. There's only one type of electricity, Coulomb charge. The line went on to mention different types of charged particles, which is correct, but it is misleading to suggest that there are many "kinds" of electricity. (especially when it is only two paragraphs later than the line stating that Faraday discovered that there was only one kind of electricity.) Geoffrey.landis 13:16, 28 June 2007 (UTC)

There is the charged current carried by the W boson, not carried by electrons, but is still the movement of electrical charge. Does that count as another type of electricity? Faraday didn't know about the weak force or W bosons. Gah4 (talk) 19:37, 26 April 2020 (UTC)

Net charge of the universe

What is it? Anyone know? —Preceding unsigned comment added by 88.109.100.75 (talk) 02:22, 10 September 2007 (UTC)

lowercase

Can we clarify the distinction in meaning between Q and q? — Omegatron 02:37, 3 November 2007 (UTC)

Template:Electromagnetism_vs_Template:Electromagnetism2

I think the Electromagnetism template is too long. I created the alternative version shown in this article; see a more extended explanation at Talk:Electrostatics#Template:Electromagnetism_vs_Template:Electromagnetism2. Comments welcome!--DJIndica 17:21, 5 November 2007 (UTC)

Hello?!

it doesnt say what is an electrically charged particle is

somebody please make a page abut it —Preceding unsigned comment added by 68.114.163.103 (talk) 02:18, 27 February 2009 (UTC)

History

History section needs resourcing... Could somebody check the previous edits and make the changes ? I tried undoing uptil the last best version but couldn't... Thanks WikifingHelper (talk) 19:09, 16 March 2009 (UTC)

I restored the History section from this version: [2]. --Kkmurray (talk) 00:50, 17 March 2009 (UTC)

Overview

I think there is a problem with the following statement: "This charge is often zero, because matter is made of atoms, and atoms all have equal numbers of protons and electrons. More generally, in every molecule, the number of anions (negatively charged atoms) equals the number of cations (positively charged atoms)." If all atoms have equal numbers of protons and electrons, then how do we explain anions and cations?? And there are plenty of molecules that have a non-zero charge. for example, most proteins are charged.Pedunculopontine (talk) 19:57, 22 July 2010 (UTC)

units

charge has units of M^(1/2)*L^(3/2)*T^(-1)

M = mass

L = length

T = time

Just granpa (talk) 06:30, 5 March 2012 (UTC)

This is true in Gaussian units, false in SI units. What's your point? --Steve (talk) 13:38, 5 March 2012 (UTC)

The section "Properties"

I think the section "Properties" there is either an error or vandalism. I think, the faster the electricity flows, the more energy you get. The voltage (difference in charge at a wires endpoints) , causes the speed of the electrons flowing through a wire. The section in this article says that the faster the electrons travel, the charge remains the same. I don't believe this to be true. I have proof in the form of another website, though I can't verify the accuracy of it. Though it is a instructional website, so why would it be wrong? The link: http://www.scottaaronson.com/blog/?p=220 Scroll down to the definition of the different properties of electricity, and you will see "Energy", the last sentence of the paragraph explains something in contrast to the section I mentioned which is in this article. I'm not entirely sure, I don't know a lot about electricity, and the "citation needed" tag seems to be a pretty good identification for false information.BSPolice (talk) 23:21, 7 August 2012 (UTC)

What is the origin of electric charge?

Antonquery (talk) 03:03, 16 October 2013 (UTC)

Combination expression

Can this quantity be considered a combination of quantities like length, time, mass or is it independent from these mentioned quantities?--188.26.22.131 (talk) 15:48, 19 January 2015 (UTC)

It is independent. (This talk page is for discussions to improve the article. For physics questions please refer to the Wikipedia reference desk.) Ulflund (talk) 19:18, 19 January 2015 (UTC)

I see this discussion on the dimensional status of this physical quantity. It should be clearly specified in the article that system of units different from SI like cgs consider electric charge a combination of length, mass, time.--86.127.205.100 (talk) 10:05, 21 January 2015 (UTC)

To be removed.

the headline "==Static electricity and electric current==" seems to be awkward and also there is no evidence (I mean with reference ) , so i want to suggest admin to check it. Ishanbull (talk) 13:25, 4 February 2016 (UTC)

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Definition

The first sentence says "Electric charge is the physical property of matter that causes it to experience a force when placed in an electromagnetic field." Wouldn't it be more correct to say "when placed in an electric field"? An electric field can exist without a magnetic component (static) as shown farther down in the article.192.249.47.204 (talk) 19:20, 19 October 2017 (UTC)

Why make the definition narrower? — dukwon (talk) (contribs) 22:46, 19 October 2017 (UTC)

Can it be said more directly (and neutrally)? for example....

Electric charge is a property of matter. A force is always present between the charge and an electromagnetic field, when the charge and field interact.

- Avoids the ambiguous "it", which should refer only to charge, but at present can be easily (mis)read as referring to "matter".

- Avoids using "cause", which reflects only one (among several) theoretical positions

- Avoids attributing a psychological state ("experience") to charge, while emphasizing the interactive relation. ("experience a force" invites thinking that the field alone is the source.)

Sdc870 (talk) 23:35, 9 April 2018 (UTC)

Classically, the force is between particles. The field is just a mathematical convenience for computing force, but does not cause force.Constant314 (talk) 08:31, 22 April 2018 (UTC)

@Constant314: Thanks for useful the comment, which inspires a new proposal for the first sentence that tries to honour a point in MOS:FIRST ("the first sentence should tell the nonspecialist reader what, or who, the subject is.") Sdc870 (talk) 18:52, 27 April 2018 (UTC)

Electric charge is the property of matter that underlies the interaction of subatomic particles (e.g., protons, electrons, ions, muons), where these interactions are the source of electrical and magnetic phenomena. Sdc870

underlies doesn't quite seem like the best word, but at the moment I cannot think of anything better. Maybe enables, causes, produces, couples? Constant314 (talk) 20:38, 27 April 2018 (UTC)

Agree that underlies is not the best. How about: "Electric charge is the property of matter that interacts between subatomic particles (e.g., protons, electrons, ions, muons), where these interactions are the source of electrical and magnetic phenomena." Sdc870 (talk) 13:15, 29 April 2018 (UTC)

I guess I like underlies better than that. I suggest we just leave it as is for now. Somebody will come up with the ideal word or phrase. They probably already have the word and are just waiting for us to stop trying. Constant314 (talk) 21:11, 29 April 2018 (UTC)

I suggest something closer to Electric charge is a physical property that determines how an object behaves under the electromagnetic interaction. Macroscopic objects can carry electric charge, so it's not limited to being a property of subatomic particles (I wouldn't generally call ions subatomic, by the way, particularly anions). It's also not limited to being a property of matter. While 'matter' has no strict formal definition, W bosons certainly don't fall under any definition of matter, yet they carry electric charge. A charge of an interaction is generally how susceptible a body is to that interaction. — dukwon (talk) (contribs) 10:27, 30 April 2018 (UTC)

Constant314: Probably you are right. But now I will try again

dukwon: Many valid points. I share your discomfort with matter in this situation. Here is another rough draft aimed at handling a variety of pitfalls.

Electric charge is the fundamental property of all objects (from elementary particles to everyday objects) involved in electrical attraction or repulsion (via electrical forces) to other objects.

Sdc870 (talk) 16:49, 2 May 2018 (UTC)

PROPOSAL and VOTING

I made a correction but it was reverted. Either we change the article on matter, antimatter and bosons or, the definition here will be misleading. According to the article on matter, "the mediators of the electric force (photons) possess energy (see Planck relation) and the mediators of the weak force (W and Z bosons) have mass, but neither are considered matter..." If W bosons are not considered to be matter, the definition should explicitly state that W bosons can also have electric charge. Since 2018, this definition has been shown to be wrong. As User:Dukwon said, W bosons are NOT matter. If matter and antimatter are the same why do we have two separate articles? And even if they can be put together, would it be harmful or beneficial to explicitly point out that antimatter can also have electric charge? If bosons are matter, why so many authors say they are not? At least the definition should read "matter (including antimatter) and W bosons...". But User:Dja1979 decided to keep the wrong version and reverted my edit. I cannot believe that this definition has been incomplete at least for 6 YEARS (since 2018) after more than one contributor expressed that it is not right. If there is disagreement, we can vote. I am confident most people will point out that it is necessary to make sure readers understand what both elementary and composite particles of matter (and antimatter) and W bosons may have electric charge. I used to be able to point my students to Wikipedia articles but the definition here is not taking into account our current knowledge and standard theories. Every time I send a student to read the definition here, I have to tell him that both antimatter and W bosons, in current models, may also feature electric charge. Besides, I added the adverb "electrically" before the adjective neutral as there is also neutral net "color" charge. I have another objection, for instance, it reads that charges are "commonly" carried by electrons and protons "by convention". It is confusing as it makes people think that if the charge is positive, I can, by convention, use a proton. That is wrong. We have to use the actual particle. It may be a proton, a positron, an antimuon, etc. They are not exchangeable. It should read that "by convention, the charge associated to electrons is "negative" and that associated to protons, positive. Other particles are also associated with one or the other type of charge." Besides, the term "ordinary" matter is used without stating what it is. It makes people think only of atoms with electrons and protons. Electric charges have to do with a lot more particles. These statements promote skewed/biased/limited ideas.

My proposal for the first paragraph is:

Electric charge is the physical property of matter (including antimatter) and W bosons that causes them to experience a force when placed in an electromagnetic field. Electric charge can be positive or negative. Like charges repel each other and unlike charges attract each other. An object with an absence of net electric charge is referred to as electrically neutral. By convention, positive charge is associated with certain particles and negative one with others. For instance, in an atom, protons have a positive net charge; and, electrons, a negative one. Early knowledge of how charged substances interact is now called classical electrodynamics, and is still accurate for problems that do not require consideration of quantum effects.

Therefore, I propose we vote on three subjects:

(1)Should the definition be more explicit about antimatter and W bosons featuring also electric charge at the introductory paragraph?

(2)Should the adverb "electrically" be placed in front of the adjective "neutral" at least at the introductory paragraph?

(3)Should we rewrite all the statements about how particles are associated with positive or negative charges throughout the article? .

George Rodney Maruri Game (talk) 19:33, 16 June 2023 (UTC)

You sound a little incensed, and this is a bit too much of a wall of text to deal with. I think the process that has been followed in the article edits is adequate. Also keep in mind that terminology is a bit fuzzy: we have no universal definition of "matter". —Quondum 20:01, 16 June 2023 (UTC)

I think that the article was fine before your "correction". Matter used as it was usually includes anti-matter. Constant314 (talk) 21:16, 16 June 2023 (UTC)

I think the disconnect here is macroscopic view versa subatomic view. The current first sentence does not satisfy either view. Charge plates or static kittens are rarely viewed as "matter". Bosons are debatable.

So perhaps the real problem is "matter": to avoid definitions in terms of ambiguous terms.

Here is an alternative:

Electric charge is a physical property inherent in certain elementary particles but manifest in macroscopic objects as electricity.

Also: the second paragraph fails in that it includes "In ordinary matter," but does not follow up with "In ?? matter" or what ever. The reader -- or at least this reader -- scans a few times and leaves frustrated.

HTH Johnjbarton (talk) 22:08, 16 June 2023 (UTC)

I completely disagree. This article, and especially its lead, is addressed to a wide audience. It must make its basic statements with no reference to particles, subatomic matter, and even removing the reference to matter altogether would be good. Remove extraneous stuff, don't try to make it applicable or central when it isn't. —Quondum 00:04, 17 June 2023 (UTC)

I don't see how we can avoid mentioning matter. Constant314 (talk) 01:31, 17 June 2023 (UTC)

In the first sentence of the lead, I expect we can. "... is the physical property of matter that causes matter to ..." is atrocious language use, besides. —Quondum 01:44, 17 June 2023 (UTC)

Ok I've given my proposal for what is minimal, basic information about the subject. Suggestion? Johnjbarton (talk) 01:49, 17 June 2023 (UTC)

Electric charge is the physical property of matter that allows interaction with the electromagnetic force.

or

Electric charge is the physical property of matter that allows coupling with the electromagnetic force. Constant314 (talk) 02:28, 17 June 2023 (UTC)

I think "electromagnetic force" has issues (it seems to be used largely in particle physics, in contradistinction to gravitational, weak and strong forces, and in classical physics, it could be taken to mean the force that results from the action of an electromagnetic field). If we can agree that in this context, "matter" is a general term, and that we will not quibble about artificial (and poorly accepted?) classifications of whether bosons are "matter", it is usable, otherwise we could substitute use "anything" or "objects". Johnjbarton makes a point about macroscopic versus microscopic views; it makes sense to present a purely macroscopic view in the first paragraph, and relate that to the microscopic view in the second. It is actually quite close already (I would accept it as it is with the removal of the "of matter" or the replacement of the second "matter" replacement with "it"). A suggestion "Electric charge is a physical property (*) that results in a force (**) from an ambient electromagnetic field." We could insert (*) "of [anything|matter|an object]" or (**) "on [anything|matter|an object]".

I am not a fan of linking to neutral particle from the first sentence as this article does not explain electrical neutrality in a general sense; Headbomb reinserted it, evidently not seeing my commented removal since a fuller edit comment would have been appropriate in response. —Quondum 11:20, 17 June 2023 (UTC)

I saw your removal, I just disagree with it. That neutral particle is in a sorry state is a case to improve that article, not to remove the link. Headbomb {t · c · p · b} 12:11, 17 June 2023 (UTC)

I prefer electromagnetic force over electromagnetic field because force and charge are fundamental. Force does things. The field is just a mathematical result of F/q. The field is a useful intellectual construct that allows us to computationally ignore action at a distance. On a more fundamental level, charge allows particles to interact with photons, but I don't want that in the lede. The field is an artifice for predicting the average effect of a large number of photons. Constant314 (talk) 12:34, 17 June 2023 (UTC)

I would argue just the opposite: force is artificial and electromagnetic field is fundamental. In the introduction I would prefer electromagnetic field.

Although "force" is a very intuitive concept, it only plays a role in the Newtonian formulation of classical mechanics, where it is used as an auxiliary variable to account for momentum transfer between two objects (e.g. gravity) or between a charged object and the EM field (Lorentz force). Analytical formulations of classical mechanics do not use a concept of force, but instead describe the EM interactions in terms of a coupling between objects and the EM field, the magnitude of which is determined by the charge.

The concept of EM field only looks articial in the static case where you do not have any interesting dynamics of the in the field and can equally well describe the interaction in terms of the Coulomb force. But if you want to account for the momentum and energy conservation in the dynamic case, you have to include the momentum and energy carried by the EM field, so that the field clearly acquires some reality. Besides, EM field is usually understood to be more than just its classical approximation: In QFT, photons are the excitations of the EM field. Jähmefyysikko (talk) 15:31, 17 June 2023 (UTC)

I appreciate your point of view, but I feel like it is at an academic level that is too high for the lede. Even pre-teens have a notion of force. Electromagnetic force is a very general term that includes the idea of Newtonian force, classical electromagnetic fields, photons, QED, QFT. Electromagnetic force is the name for the phenomenon. Those other things, are, as you say, analytical formulations; they are inventions of the human mind used for calculating predictions; they are entities that exist only within the framework of a theory. And yes, the EM field does a good job of accounting for momentum and energy conservation, on the average. It is a very effective manifestation of human imagination. It is so effective, that it is tempting to just go ahead and pretend that the field is physically there.

Feynman says in section 15-4 of The Vector Potential, "a real field is a mathematical function we use for avoiding the idea of action at a distance," and "a “real” field is then a set of numbers we specify in such a way that what happens at a point depends only on the numbers at that point." Notice the underlined words, a real field is nothing but numbers. The value of those numbers and their dynamics are assigned by useful physical theories. Constant314 (talk) 16:06, 17 June 2023 (UTC)

Even a school-grader will have issues with the gross oversimplification in your line of thinking: we do not and cannot measure the electromagnetic field itself in the unit newton. You also misinterpret Feynman. He is choosing words to convey to an uninitiated audience something of what a field is, and is limited in the words that he has available in the context. He did not say that a field is nothing but numbers. The quote says that the field can fully be described by a set numbers at each point, which is exactly how we describe fields in physics. —Quondum 20:24, 17 June 2023 (UTC)

Not sure what you mean with "Even a school-grader will have issues with the gross oversimplification in your line of thinking". My line of thinking is this: only mention the electromagnetic force and say nothing about the field, in the lede.

Regarding Feynman, I think I am right on. He says, "a “real” field is then a set of numbers." He doesn't say that a field is something that can be described by numbers. He says a field is numbers. Constant314 (talk) 23:14, 17 June 2023 (UTC)

I too think that you are taking Feynman out of context. The chapter is about vector potential and what he is arguing is that the vector potential is as real as the magnetic field, not that the EM field would not be a physical field.

But sure, academically, we can remove the EM field from the physical picture (by "integrating out the photons") and use a complicated retarded potential to describe the force between electrons. This would mean that we we would regard the manifestations of the EM field such as photons, radio waves and light as physically nonexistent. It is perhaps not the most natural way of thinking.

And I am not arguing for the existence of the classical field, but the underlaying quantum field, so its hard to see the relevance of the comment about average values. Jähmefyysikko (talk) 11:01, 18 June 2023 (UTC)

Yes, Feynman's context is a discussion about the vector potential. But he does not limit the discussion to the vector potential. He says that (paraphrasing) real fields are numbers. That is all he says. You may argue that he didn't tell the whole story. I am pressed for time at the moment, but later today, I have three more references, some that sort of support your point of view. Constant314 (talk) 15:12, 19 June 2023 (UTC)

In physics, everything is modeled with mathematics. Some of the mathematical models seem robust enough that we assign a rather subjective element of reality to them. A force is also only a set of numbers, so there is no difference to a field in this sense.

Re-reading Feynman here, what he really is saying is that we should think of a field as "real" (his quotation marks) only if it does not involve action-at-a-distance. Considering Aharonov-Bohm experiment, he claims that the vector potential fits the bill, but the magnetic field does not, and we should regard vector potential as more fundamental. Jähmefyysikko (talk) 16:48, 19 June 2023 (UTC)

"In physics, everything is modeled with mathematics. Some of the mathematical models seem robust enough that we assign a rather subjective element of reality to them." - I agree with that. We absolutely do that. Sometimes, it leads us to wrong conclusions.

"A force is also only a set of numbers, so there is no difference to a field in this sense." Perhaps this is the heart of our disagreement. You perhaps are using a narrow definition of force. Electromagnetic force, in the sense I intend to use it, is a for the name of the phenomenon. I would also be satisfied with electromagnetic interaction or even electromagnetic phenomena if that is more agreeable. Constant314 (talk) 22:42, 19 June 2023 (UTC)

When you take away the field, the electromagnetic force (in the broad sense) reduces to a set of forces (in the narrow sense) which are functions of the positions of the charges: mere numbers.

So this is not the disagreement. The disagreement is in whether the EM field and its excitations such as light exist. It relates to whether momentum and energy are conserved. In your picture, when a photon is emitted, its momentum and energy vanish from this world, only to re-emerge later when it is absorbed. There is no momentum and energy conservation even in the classical limit. That is a high price to pay for no gain. Jähmefyysikko (talk) 05:25, 20 June 2023 (UTC)

Furthermore, his no-action-at-a-distance criterion clearly invalidates the "reality" of the a force acting from distance without a mediating field.

I am insisting on talking about the context here, since I do not think you can use Feynman's possible authority without acknowledging his intended meaning. Jähmefyysikko (talk) 17:41, 19 June 2023 (UTC)

"Furthermore, his no-action-at-a-distance criterion clearly invalidates the "reality" of a force acting from distance without a mediating field." - That is a logical error. A real field does not eliminate force at a distance. A real field only allows you to ignore force at a distance in your calculation, if you have the value of the real field at the point at which you wish to calculate. Real fields don't do anything except facilitate computation.

"I am insisting on talking about the context here, since I do not think you can use Feynman's possible authority without acknowledging his intended meaning." - None of us is competent to determine Feynman's intended meaning, although I agree that he was certainly making the case the vector potential was a real field whereas the magnetic field failed to be a real field. I do believe that Feynman meant all real fields are numbers when we said "a “real” field is then a set of numbers". Constant314 (talk) 22:58, 19 June 2023 (UTC)

To me the lead sentence needs to help readers decide: "ooo...electric charge! tell me more" or "that electric charge, got it". We have an entire article to delve in to aspects. The sentence doesn't have to have matter or electromagnetism or solve all problems, IMO.

How about:

Electric charge is the physical quantity of electricity. Johnjbarton (talk) 14:44, 17 June 2023 (UTC)

I don't like that. Matter needs to be mentioned. Headbomb {t · c · p · b} 20:48, 17 June 2023 (UTC)

I agree. Constant314 (talk) 23:14, 17 June 2023 (UTC)

Revised version of lead section

I accepted the challenge to be bold and spent some time trying to reorganize and refine the lead section. I have not deleted any content from the previous version, but I have tried to organise it better, remove some redundancy, elaborate a few points, and address various problems noted here in Talk, including (a) the 2012 discussion on one vs. two types of charge and the inconsistency with the later text, (b) the 2006 request for a simple definition, (c) 2006 query about ‟quantized” and (d) the 2017/8 discussion about the first sentence. Also added a few source citations. Will be happy to explain various choices. No doubt it can be improved….

Meanwhile -- I wonder (casually) if the lead section should be so long? -- given that the "Overview" explains (often better) many of the things in the lead section! Here is the lead section from October 2008. Not bad for a "short" introduction.

Electric charge is a fundamental conserved property of some subatomic particles, which determines their electromagnetic interaction. Electrically charged matter is influenced by, and produces, electromagnetic fields. The interaction between a moving charge and an electromagnetic field is the source of the electromagnetic force, which is one of the four fundamental forces.

Sdc870 (talk) 20:24, 21 April 2018 (UTC)

Sdc870, thank you for your many contributions. The vast majority of your contributions I believe are good. Also, your most recent addition to this article appears to have added 3 references. However, you also added a citation needed tag to your own addition in the lead section of this article, which makes me think you are doubtful of your own work. Because your most recent addition was +2190 bytes, I have a hard time sifting through everything and discriminating the good from the bad. Please make smaller changes and discuss them first, unless you are VERY sure that you are correct about everything. Thanks. Brian Everlasting (talk) 00:19, 22 April 2018 (UTC)

@Brian Everlasting: Happy to discuss. (was uncertain about how to proceed - sought advice, which led to my bold action). Also happy to make small increments -- but should I propose them here first? -- or just make them directly as edits in the lead section? To start: my proposals in relation to the first paragraph are:

• change the first sentence to: "Electric charge is a property of matter that underlies electromagnetic interaction." (Some of the reasons are discussed in the topic previous to this one)
• Add a sentence that makes "matter" more precise: "Electric charge is carried by subatomic particles (such as protons, electrons, ions, muons)."
• Move the "unit" discussion to the bottom of the section.
• About "citation needed" -- I was just referring to a point in the "to do" section on the top of this talk page. I did not have a good reference, but I believe the point is valid.
• Some small adjustment in the discussion about positive and negative charge (with source) and another source about what charge is.

I could try to make these changes in two or three steps/edits. Sdc870 (talk) 01:29, 22 April 2018 (UTC)

charge

Properties should be there of charge, In a different heading - jarvis12ka4@gmail.com Ironman12ka4 (talk) 04:14, 31 May 2018 (UTC)

proposal to remove section

Does the section "The role of charge in electrostatics" provide any information that does not already appear in the "Overview" section? If not, then I would propose to eliminate it, or to integrate it with the "Overview" section. Sdc870 (talk) 10:51, 10 October 2018 (UTC)

Sounds reasonable to me.Constant314 (talk) 16:08, 10 October 2018 (UTC)

2019_redefinition_of_the_SI_base_units

It seems to me that, at least the definition of Faraday, changes with 2019_redefinition_of_the_SI_base_units. Probably some other things on this page. Gah4 (talk) 19:44, 11 June 2019 (UTC)

CURRENT ELECTRICITY

topic:current electricity'''

sub-topic:current flowing through battery/source question:when ever battery or any other source is applied to the circuit, current start flowing through it because number of positive and negative charges are not equal.So the question is why the number of positive and negative charges are not equal? 182.182.238.250 (talk) 03:27, 5 September 2020 (UTC)ahtishamsaleem8158@gmail.com. 8:26,05 september2020.

Hi. Wikipedia is not a question and answer forum. You might try Quora or some other forum. Constant314 (talk) 05:20, 5 September 2020 (UTC)

Omitted edit comment on "modern" terminology

I inadequately commented my removal of In modern practice, the phrase "amount of charge" is used instead of "quantity of charge" in my edit. The sentence is, to start with, is a misquote of Modern practice is to use the phrase "amount of electricity" rather than "quantity of electricity", which appears in a side note of an appendix of the 8th SI Brochure, which gives Resolution 12 of the 11th CGPM, 1960. This side note has been retained in the appendix of the 9th SI Brochure, but we could conjecture that this is rather dated and was retained only as an editorial oversight, given that the brochure itself has completely removed both phrases from its text, replaced by "electric charge" except in the historical appendix with the note. The evolution of the term may be seen from the progression of the phrase in the table of derived units in the editions of the brochure:

4th SI Brochure (1981): "quantité d'électricité"

5th SI Brochure (1985): "electric charge, quantity of electricity"

6th SI Brochure (1991): "electric charge, quantity of electricity"

7th SI Brochure (1998): "electric charge, quantity of electricity"

8th SI Brochure (2006): "electric charge, amount of electricity"

9th SI Brochure (2019): "electric charge"

I find this ngram illuminating. Given that the quoted reference seems to out of step with true "modern" use, retaining the sentence in even a corrected form seemed (to me) to be somewhat pointless. 172.82.46.195 (talk) 15:28, 24 July 2022 (UTC)

Some sources and quotes about the physical existence of the field

• Richard Feynman The Vector Potential. In section 15-4,

• "A real field is a mathematical function we use for avoiding the idea of action at a distance."
• "A “real” field is then a set of numbers we specify in such a way that what happens at a point depends only on the numbers at that point."

Comment: Feynman does not say that a real field is something that can be represented by numbers. He says that a real field is numbers.

• John David Jackson

"It [the electric field] is a vector function of position, denoted by E."

Comment: A vector function is just an ordered set of numbers. This is all Jackson says.

• Edward M. Purcell

"Is it [the electric field] something real or is it merely a name for a factor in an equation ... since it works, it doesn't make any difference."

Comment: You can assume that the electric field is something real and I can assume that it is nothing, but numbers attached to points in space, and we will both get the right answer. If you assume that the field acts in anyway different from numbers attached to points in space, you will get a wrong answer.

• David J. Griffiths

"I encourage you to think of the field as a real physical entity ... I can't tell you, then, what a real field is -- only how to calculate it and what it can do for you once you've got it."

Comment: Griffiths likes to think of the field as physical. Many people also think that. But he is not going to tell you that it is physical, because he cannot. He cannot give you any reason to believe that the field is anything other than numbers attached to points in space. But notice the words he uses. He can tell you what the numbers that you calculate can be used for, but he does not say that he can tell you what the field does. Numbers cannot do anything. If Griffiths could tell you anything that the field does, that numbers attached to points in space cannot do, then he would have evidence of the field being physical.

Constant314 (talk) 02:38, 20 June 2023 (UTC)

Again, for context: both Griffiths[3] and Purcell[4] are discussing electrostatics here and introducing the electric field for the first time.

Let me also give you a quote: "For static problems, the “action-at-a-distance” and field points of view are completely equivalent. The true superiority of the field approach becomes evident only when we turn to time-dependent problems. In that context, we will see that fields can exist quite independently of the presence or absence of charged particles. We will endow them with properties like energy, linear momentum, and angular momentum and treat them as dynamical objects with the same mechanical status as the particles." (Zangwill, Modern electrodynamics, p.34) Jähmefyysikko (talk) 07:19, 20 June 2023 (UTC)

And Jackson is not so agnostic about the existence of electromagnetic field either: (Jackson p.3)

"Second, electromagnetic fields can exist in regions of space where there are no sources. They can carry energy, momentum, and angular momentum and so have an existence totally independent of charges and currents. In fact, though there are recurring attempts to eliminate explicit reference to the fields in favor of action-at-a-distance descriptions of the interaction of charged particles, the concept of the electromagnetic field is one of the most fruitful ideas of physics, both classically and quantum mechanically." Jähmefyysikko (talk) 11:38, 20 June 2023 (UTC)

I agree with your comment that Griffiths and Purcell are discussing electrostatics. However, I believe that their comments were intended to be general. Reasonable people can disagree.

I agree entirely with the quote from Jackson. I am not trying to eliminate the field from the article, only the first paragraph.

As for Zangwill, I must deconstruct the quoted material.

• "fields" -- Not sure what he means by plural. If he means that, for example, the electromagnetic field and the gravitational field are two fields, then I agree.
• "fields can exist quite independently of the presence or absence of charged particles" -- I absolutely agree. Yes, numbers attached to points in space can exist without charged particles. They may be zero, but they are still numbers.
• "We will endow them with properties like energy, linear momentum, and angular momentum" -- I agree. Even Feynamn says that it is pragmatic to do so.
• "treat them as dynamical objects with the same mechanical status as the particles." I am going to have to more context. It depends on exactly what he means by particles. If he means that the EM field has the same mechanical status as a photon, then I am fine with that. If he means that the EM field has the same mechanical status as a pebble, then I would need more explanation. I don't think that we need particles in the first paragraph either.

Constant314 (talk) 16:15, 20 June 2023 (UTC)

Seems to me that you both have some great material for a section in electric field. Perhaps "Reality of electric fields" or "Interpretation of electric fields", at or near the end of the article.

I know it will be a challenge to adopt neutral language on a topic you seem to have personal commitment to, but I think it would a valuable contribution, addressing a question many readers may have. The questions of science are just as important as the answers. Johnjbarton (talk) 16:01, 20 June 2023 (UTC)

That would not belong in this article, which is about electric charge. Besides, articles are not places for analyses of positions of interpretation when positions in the literature are unclear. As we can see, two editors can read wildly different things into exactly the same sources. —Quondum 16:15, 20 June 2023 (UTC)

I agree with that. After the smoke clears, I only desire for the article is that the first paragraph not mention any theoretical constructs such as fields or photons. I would find any of the following statements to be agreeable:

• Charge is the property of matter that allows it to experience electromagnetic phenomena.
• Charge is the property of matter that allows it to experience electromagnetic effects.
• Charge is the property of matter that allows it to experience the electromagnetic force [I take force in this use as the common term that includes all electromagnetic phenomena].
• Charge is the property of matter that allows it to participate in the electromagnetic interaction.
• Charge is the property of matter that allows it to interact electromagnetically with other charged matter.

Is it possible that we could agree on one of those statements? Constant314 (talk) 16:28, 20 June 2023 (UTC)

Charge is the property assigned to matter to explain its response to electromagnetic interactions. Johnjbarton (talk) 17:01, 20 June 2023 (UTC)

That is agreeable to me. Constant314 (talk) 20:23, 20 June 2023 (UTC)

Scientific disagreements are part of the world just as much as the results of experiments or their interpretation. An encyclopedia should cover disagreements using the same criteria it uses for covering other topics. We have entire pages devoted to such topics, eg Interpretations of quantum mechanics. Johnjbarton (talk) 16:54, 20 June 2023 (UTC)

I disagree. That is just mumbo-jumbo that says nothing. And while we have articles that cover scientific disagreements, this article is not one of them. The lead should give a clear, mainstream perspective. —Quondum 17:07, 20 June 2023 (UTC)

Please re-read my comment. It said: " some great material for a section in electric field."

I agree the lead should give a clear mainstream perspective such as any one of the several I have suggested in various replies.

Please don't characterize my suggestions as mumbo-jumbo. Johnjbarton (talk) 19:41, 20 June 2023 (UTC)

Sorry, I missed that; I guess it could be discussed there. And look, no disrespect to you intended. Let me put my thoughts more explicitly: I find that the suggestion seems circular, since "electromagnetic interaction" is precisely the interaction of charge and the field (except that the word "field "seems to be what you are trying to avoid, so should we define, circularly, or that these "electromagnetic interactions" are the response of charges to "electromagnetic interactions"?) —Quondum 21:18, 20 June 2023 (UTC)

I advocate a phenomenological first sentence: one that relies on observations rather than interpretation.

"Field" is an interpretation. My "interaction" was intended to be a catchall for "things that happen". Maybe there are better words, but I think we can't go wrong with expressing the concept in terms of observations.

There is nothing wrong with circularity, when reflects reality. Historically "charge" has a long, very long, tortuous and circular history. Consider |"Vitreous and Resinous electricity". Most of the work is by comparison, and thus naturally circular. To the present day we think we know so much, but really, negative charge is just circularly defined as opposite positive charge. Johnjbarton (talk) 23:46, 20 June 2023 (UTC)

We should not present incomplete accounts of the past when a modern mainstream approach is self-consist and non-circular. This approach does not shy away from the reality of the electromagnetic field. —Quondum 00:00, 21 June 2023 (UTC)

I agree. I want to connect charge with some common term (like force, response, interaction, effect) for all EM phenomena rather than jargon (like field or photon). Constant314 (talk) 00:21, 21 June 2023 (UTC)

'field' and 'photon' are not jargon. They are real, concrete, things that exist. Dismissing photons as jargon is like saying electrons or protons are jargon, thus can't be mentioned. Headbomb {t · c · p · b} 00:48, 21 June 2023 (UTC)

It is jargon to a nineth grade reader. Of course, they are jargon. Constant314 (talk) 01:05, 21 June 2023 (UTC)

References