Talk:Plasma (physics)

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I want to edit the math equations in this article so that they display correctly. For whatever reason all of the equations are not rendering correctly.

For Example: this is the code for an equation directly from the source of the article: $${\displaystyle \alpha ={\frac {n_{i}}{n_{i}+n_{n}}},}$$ It renders like this: $ {\displaystyle \alpha ={\frac {n_{i{n_{i}+n_{n}}},} $

I would like to fix this please. If not me than someone else.

}} viv (talk) 21:49, 27 July 2024 (UTC)

The equation renders just fine for me. Maybe try a different web browser/clean the cache/etc. In any case, do you see a mistake in the latex math code? If not, how are you going to fix it? Evgeny (talk) 08:20, 28 July 2024 (UTC)

 Not done: Everything is rendering correctly for me as well. PianoDan (talk) 17:15, 8 August 2024 (UTC)

I apologize, it must be on my end somehow, I checked out equations on another Physics page. Really sorry about that, we can close this. Ill troubleshoot my rendering of the wiki, it usually doesn't have an issue rendering latex code but I have had issues with how Latex code was integrated into wikimedia sites before. viv (talk) 20:30, 12 August 2024 (UTC)

Explanation: The word "plasma" was not used until Langmuir coined it. So although plasma has been observed since the dawn of time, any observation of it in any the laboratory would qualify for consideration as it being "identified".

Faraday's major systematic study of arcs, sparks and lowered pressure glows was published in Michael Faraday (1838) "VIII. Experimental researches in electricity. — Thirteenth series.," Philosophical Transactions of the Royal Society of London, 128 : 125-168. https://books.google.com/books?id=ypNDAAAAcAAJ&pg=PA125#v=onepage&q&f=false

That was long before Crookes or Langmuir. So the following is false:

"Plasma was first identified in laboratory by Sir William Crookes." and should be replaced with a statement like

"Michael Faraday studied the light observed in electrical discharges in air and some other gases at atmospheric and lowered pressures. [reference Michael Faraday (1838) "VIII. Experimental researches in electricity. — Thirteenth series.," Philosophical Transactions of the Royal Society of London, 128 : 125-168. https://books.google.com/books?id=ypNDAAAAcAAJ&pg=PA125#v=onepage&q&f=false]

The following is true and worth retaining but it is not the first laboratory study

Crookes presented a lecture on what he called "radiant matter" to the British Association for the Advancement of Science, in Sheffield, on Friday, 22 August 1879.[13]

The start of the section about Langmuir is also false because of Faraday's (and Crookes') work. and should be replaced by

'Irving Langmuir and his colleagues in the 1920s conducted extensive experimental and theoretical studies of low pressure ionized gases in the 1920s; and introduced the term "plasma" as a description of ionized gas in 1928:[14]

   Except near the electrodes, where there are sheaths containing
   very few electrons, the ionized gas contains ions and electrons in
   about equal numbers so that the resultant space charge is very
   small. We shall use the name plasma to describe this region
   containing balanced charges of ions and electrons.

Lewi Tonks and Harold Mott-Smith, both of whom worked with Langmuir in the 1920s, recall that Langmuir first used the term by analogy with the blood plasma.[15][16] Mott-Smith recalls, in particular, that the transport of electrons from thermionic filaments reminded Langmuir of "the way blood plasma carries red and white corpuscles and germs."[17] ' Ihhutch (talk) 15:38, 24 November 2025 (UTC)

Oops! The second "in the 1920s" was accidental repetition and should be deleted from my suggestion. Ihhutch (talk) 15:41, 24 November 2025 (UTC)

No, observation is not the same as identification. One can observe a phenomenon without actually understanding it's something principally new. I am not certain that Crookes' observations can be qualified as as identification, but Faraday's for sure couldn't. If you believe otherwise, please quote specific text. Evgeny (talk) 10:50, 25 November 2025 (UTC)

I gave the Faraday reference. Which is a long detailed account of his observations of visible light and its spatial configuration when discharges between two electrodes are observed. Crookes' observations, though at lower pressure were basically of the same type as Faraday's.

The electron had not even been discovered when they were writing, so neither of them had much understanding of the phenomenon. In no sense had either of them "identified" the underlying mechanism. They were both reporting phenomena, observed systematically. It is often misleading to talk about something being "first identified". This is a prime case. Crookes made important studies; but so did Faraday, 39 years earlier. My intention is to correct the misleading assertion of who first "identified" plasma, and replace it with documented facts, rather than disputable claims of priorities. Ihhutch (talk) 13:54, 25 November 2025 (UTC)

The discovery of electron is not really relevant here. Just as it wasn't for the discovery of various phenomena of electromagnetism. My point is that producing a kind of plasma in the laboratory doesn't substitute for realization that it's a principally different form of matter with many phenomena specific just to it. Lighting a candle is also producing a (weakly ionized) plasma - its flame. And this has been done zillion of times in various laboratories.

As I mentioned, I'm not strongly attached to the opinion that Crookes "identified" plasma. If there is a consensus that Crookes and Faraday basically did (and understood) the same, I'd rather then mention neither instead of both. Evgeny (talk) 14:36, 25 November 2025 (UTC)

I think it would be fair to say that Crookes (perhaps first) called plasma the fourth state of matter. So my suggestion is that the first two paragraphs ought to be:

"

Michael Faraday studied the light observed in electrical discharges in air and some other gases at different pressures. [reference Michael Faraday (1838) "VIII. Experimental researches in electricity. — Thirteenth series.," Philosophical Transactions of the Royal Society of London, 128 : 125-168. https://books.google.com/books?id=ypNDAAAAcAAJ&pg=PA125#v=onepage&q&f=false]

William Crookes investigated related discharges at even lower pressure, which his improved vacuum technique enabled him to reach. He summarized the work in a lecture to the British Association for the Advancement of Science, in Sheffield, on Friday, 22 August 1879 entitled "Radiant Matter", calling it the "fourth state of matter".[13]

"

[Sorry I don't know yet how to do footnote references in wikipedia. It would make sense to have links to the Wikipedia articles: Michael Faraday, William Crookes, and the Crookes Tube] Ihhutch (talk) 22:03, 25 November 2025 (UTC)

OK, reading Crookes' lecture carefully, I now realized it was in fact Faraday who first used the "fourth state of matter" term - and as early as in 1819. Thank you for insisting, I'll update the section. Evgeny (talk) 09:48, 27 November 2025 (UTC)

I have started a new topic on your edited version since this exchange is getting long.

Broadly your edit contains claims unsupported by what references you give. Ihhutch (talk) 15:36, 28 November 2025 (UTC)