Talk:Charge conservation

something wrong

I think there's some mistake in the Mathmatics derivation section. the "dq" in the $I={\frac {dq}{dt}}$ means charge over the bound of the V in the period "dt".So We can't just think q means the charge remains in the V,otherwise we make a mistake that we think charge like ping-pongs and the total amount remains the same.That is just what we want to prove.

Yes,we can use this derivation to prove the last equation is correct,but we don't prove the law because we just use the law in our derivation!Through the derivation we just know the last equation is one of the expressions of the natural law.

In the derivation we don't use any Physics knowledge except for some definitions. Maybe we'd better write something else(not that misunderstanding)in this section.For example,use Maxwell's equations to "prove" the law. —Preceding unsigned comment added by 222.29.46.239 (talk) 08:52, 7 March 2010 (UTC)[reply]

I think the integral at the start of the derivation is a colsed surface integral in order to define a volume. Is this true? — Preceding unsigned comment added by 129.12.24.211 (talk) 09:15, 22 April 2016 (UTC)[reply]

Simpler explanation

If no one objects I would like to add a simpler explanation of charge conservation, in the introduction, for the general reader. Ti-30X (talk) 00:27, 21 May 2009 (UTC)[reply]

The introductory explanation is already simple. I suppose I had something else in mind, like a history of charge conservation, or how and when it was first articulated, and its importance to present day physics. Something like that. Ti-30X (talk) 14:43, 1 July 2009 (UTC)[reply]

Great additions

Just wanted to congratulate David C Bailey on his great additions to the article. The excellent Franklin quote, the desperately needed section on experimental evidence, and especially the supporting citations. Its a much-improved article now. Cheers! --Chetvorno^TALK 09:09, 25 November 2010 (UTC)[reply]

'testable consequences of gauge in variance'

In the 'Connection to Gauge invariance' section I am a little troubled by the fact that it implies that gauge invariance has 'testable consequences'. This, to my knowledge, completely misses the point as gauge invariance is in fact a 'fake symmetry' - its a redundancy that we introduce into a field theory but it is not a necessity.

Assessment comment

The comment(s) below were originally left at Talk:Charge conservation/Comments, and are posted here for posterity. Following several discussions in past years, these subpages are now deprecated. The comments may be irrelevant or outdated; if so, please feel free to remove this section.

One can't derive conservation of charge. It's a law of nature. The only thing that has been derived in this article is the continuity equation, which applies equally to hydrodynamics, etc., and is merely one way of writing charge conservation. It's so misleading that it should be taken out.151.204.71.183 (talk) 19:21, 31 May 2008 (UTC)TR[reply]

Last edited at 19:21, 31 May 2008 (UTC). Substituted at 11:16, 29 April 2016 (UTC)

Absolute statements

The article says:

Simple arguments rule out some types of charge nonconservation. For example, the magnitude of the elementary charge on positive and negative particles must be exactly equal. Ordinary matter contains equal numbers of positive and negative particles, protons and electrons, in enormous quantities. If the elementary charge on the electron and proton were even slightly different, all matter would have a large electric charge and would be mutually repulsive.

I don't think it's any useful in science to make such absolute statements. Suppose, hypothetically speaking, that there was a 10^-100 e difference between electron and proton charge. Then, this would amount to less than one extra elementary charge in the whole of observable universe, and such a discrepancy would obviously not be observable. It's more accurate that both direct experiments and the fact that macroscopic objects and celestial bodies don't have a significant electric charge give a very strict limit on this difference. (According to particle data group, the upper limit on the difference between electron and positron charge is on the order of 10^-8 e, between proton and antiproton 10^-10 e, between proton and electron about 10^-21 e, and likewise for the upper limit on neutron charge. [1] [2]) - Mike Rosoft (talk) 07:33, 26 March 2017 (UTC)[reply]

I agree. Added tolerance to statement. --Chetvorno^TALK 08:51, 26 March 2017 (UTC)[reply]

When I said "the fact that macroscopic objects and celestial bodies don't have a significant electric charge", I should have also added the fact that they are stable in the first place. (For an extreme example, see the thought experiment: What if your body somehow lost 1% of its electrons? [3] To put it simply, it would have had a rather disastrous effect on both you and the Earth itself.) In any case, the claim that there's a 10^-100 e difference between electron and proton charge is an obvious example of Russell's teapot. It can't really be disproven, but there's no reason to believe it's true, and the theory says that the charge is exactly the same (just with an opposite sign). - Mike Rosoft (talk) 11:10, 26 March 2017 (UTC)[reply]

Reorganized introduction

- The previous version (from 3 Aug 2017) started with a false statement -- about charge not being created and destroyed, which was contradicted later in the text. Have changed the opening sentence -- which also aligns better with the discussion of charge conversation in the Electric Charge#Conservation_of_electric_charge article.
- Tried to reorganise/restructure the introduction so that common topics were brought together, which were separated in different parts.
- created a separate history section and moved relevant text there
- moved formal mathematical part in the introduction into the mathematical section
Sdc870 (talk) 00:46, 31 March 2018 (UTC)[reply]