Talk:Antimatter

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"common matter" instead of "ordinary matter"?

The article uses the term "ordinary matter" but this term is confusing because it is often used to refer to atomic matter. Isn't the term "common matter" a less-ambiguous term for matter that is not antimatter? DavRosen (talk) 22:43, 30 May 2018 (UTC) antiantimatter Sci09272 (talk) 19:44, 7 December 2021 (UTC)

Opening lines: "microscopic numbers"

What exactly does it mean "microscopic numbers of antimatter particles are generated daily at particle accelerators"? Microscopic? Surely all particles are microscopic? Or the numbers are exceedingly small? Which would surely be a confusing colloquialism given the subject? Can't make sense of it. Cheers. — Preceding unsigned comment added by 2A02:C7D:93D0:3600:1152:49BB:185A:23DB (talk) 15:29, 7 December 2018 (UTC)

Intriguing possibility re. antimatter lack of abundance

Hi, as its essentially been discounted that antimatter behaves much differently than matter in a gravitational field many of the assumptions on which the "antimatter moving back in time" hypothesis originally proposed by Feynman can be modified to include a simpler mechanism.

Its possible that at some level another mechanism may prevent "anti-stars" being stable therefore explaining the lack of antimatter clusters in the visible Universe, one such mechanism may well be that the weak nuclear force is different for antimatter. The side effect of this would be that elements that are not currently stable would be if they contained only anti-particles and this could be detected by measuring spectra from non-stellar regions of the Universe thus proving this hypothesis.

This can actually be tested: experiments have generated anti-helium and it behaves in a very similar way to normal helium. I wondered a little while back if antimatter could be the "spark" that initiated the first stars and could account for some anomalies in CMB. Also recent experiments show a distinct difference in the predicted versus actual behavior of positronium "atoms" suggesting that the Standard Model may require some adjustment.

References

Merge with Antiparticle

The following discussion is closed. Please do not modify it. Subsequent comments should be made in a new section. A summary of the conclusions reached follows.

Don't merge. It's been three months, and no support for a merger appeared, time to close this. Tercer (talk) 07:52, 22 April 2021 (UTC)

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There is no real distinction between the terms antimatter and antiparticle(s), and the overlap between these two articles already is huge (e.g. both explained annihilation, both explain the production and detection of positrons, antiprotons and antineutrons, both explain the capture of positrons and antiprotons to form antihydrogen, etc. 81.107.39.90 (talk) 23:35, 16 January 2021 (UTC)

I don't know, antihydrogen is clearly on topic for antimatter, but not really for antiparticle. Tercer (talk) 10:28, 18 January 2021 (UTC)

Antihydrogen is also clearly on topic for antiparticle, antiparticle does not just mean fundamental antiparticles. In addition the antiparticle article already discusses antihydrogen just like the antimatter article. 81.107.39.90 (talk) 13:50, 18 January 2021 (UTC)

I would respectfully disagree. The Antiparticle article clearly focuses on subatomic particles and provides significant mathematical treatment of the subject. Antimatter is a non-mathematical treatment and does discusses antimatter at the atomic level. While there is some overlap, they are both long articles and that seems a natural division. So I'd keep them separate.--agr (talk) 14:00, 18 January 2021 (UTC)

The antiparticle article doesn't really contain anything about subatomic antiparticles that isn't already contained in the antimatter article. The only part of the antiparticle article that isn't already covered in the antimatter article is the "Properties" and "Quantum field theory" and "Dirac hole theory" sections, which is a fairly large portion of the article, but none of them are specific to fundamental antiparticles and all of which should be on the antimatter article anyway (Even if antimatter only referred to composite antiparticles not fundamental, which it does not). Everything that is specific to fundamental antiparticles in the antiparticle article, is already in the antimatter article. 81.107.39.90 (talk) 14:10, 18 January 2021 (UTC)

The parts you describe in antiparticle that are not part of antimatter comprise most of the antiparticle article. And their tone is much more technical than antimatter's content. The antimatter article defines it as "... matter that is composed of the antiparticles..." That is a distinction that most physicists would be comfortable with, I believe. Also antiparticle is about 20k in size and antimatter 70k. Those are both reasonable sizes for Wikipedia articles. Combined they would approach the 100k limit that is considered unwieldy. See WP:Merge. So again, I don't think a merge is warranted.--agr (talk) 17:30, 18 January 2021 (UTC)

Combining wouldn't result in that much of an increase in size, as again a large part of the antiparticle article is already contained in the antimatter article. I agree the antiparticle article's tone is more technical, I don't see why that is a reason not to merge. All of the technical description in the antiparticle tone describes antimatter. If you were looking for a technical description of antimatter, and you found yourself on the antimatter article, you should expect to find it, not have it on another page for a synonymous term. There's nothing in the antiparticle article that shouldn't be in the antimatter article. If the articles were called something along the lines of "antimatter - technical" and "antimatter - non technical" this would make sense, but as it is no-one that finds themselves on the antimatter page looking for a technical description of antimatter is going to realise they need to go to the antiparticle page to get a technical description of antimatter, they're just going to think this content does not exist on wikipedia. And vice versa anyone looking for a non technical description of antiparticles that ends up on the antiparticle page aren't going to realise they need to go to the antimatter page to get a non technical description of antiparticles. 81.107.39.90 (talk) 00:35, 19 January 2021 (UTC)

The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

Reverse Matter?

Would reverse matter not more fit as definition for this atomic systems? 2A02:AA11:9102:3D80:94D9:4928:F250:4A62 (talk) 17:31, 4 April 2022 (UTC)

Two Problems with the article

1} Conceptual history section, para 2: "differed from the modern concept of antimatter in that it possessed negative gravity." Umm, while they have been working on it since 2016, the ALPHA-g experiment only ran preliminary tests in 2018 before CERN was shut down for its upgrade, and only now (2022) has beam come back on. They are still a long way from publishing their results. Until that time, we will not have demonstrated that antimatter actually falls down in gravity (however extremely likely that would be).

2) Section Artificial production, subsection Antihydrogen atoms, para. 1: "it had successfully brought into existence nine hot antihydrogen atoms by implementing the SLAC/Fermilab concept". What "SLAC/Fermilab concept"? There is no mention of this in the main antihydrogen wiki article linked from the subsection title, either, though it seems likely this is a reference to the text there "using a method first proposed by Charles Munger Jr, Stanley Brodsky and Ivan Schmidt Andrade." This all needs some clarification. 2001:56A:F0E9:9B00:2511:25BE:32B9:C4C2 (talk) 02:19, 22 November 2022 (UTC)JustSomeWikiReader

Odd sentence that appears out of place

In the first paragraph it says: "Antimatter —- it’s a visionary substance that you will see in your human computer vision like a hologram when you are contacted by God." I don't think that's what antimatter is. 195.59.7.254 (talk) 10:57, 5 December 2022 (UTC)

It isn't. Somebody had just added that sentence, I removed it. Tercer (talk) 11:22, 5 December 2022 (UTC)

Irrelevant citation [20]

The last paragraph of the Antimatter#Conceptual_history section claims that the Feynman-Stueckelberg interpretation says that antiparticles behave like normal particles traveling backward in time. I believe this is correct, but the source [20] isn't relevant to this claim. To give you an idea, it has none of the words "feynman", "stueckelberg", or "backward". It's about relative amounts of matter and antimatter in the universe, which is different topic. (There is one mention of "time reversal" in the introduction, referring to a different phenomenon, which may be the source of the confusion, or maybe someone just accidentally cited the wrong source). 2002:62B9:EB03:1:DA22:6020:6328:5E1F (talk) 23:43, 22 June 2024 (UTC)

"Anti universe" listed at Redirects for discussion

The redirect Anti universe has been listed at redirects for discussion to determine whether its use and function meets the redirect guidelines. Readers of this page are welcome to comment on this redirect at Wikipedia:Redirects for discussion/Log/2024 August 11 § Anti universe until a consensus is reached. Web-julio (talk) 02:51, 11 August 2024 (UTC)