Talk:Mass–energy equivalence/GA3

GA Review

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Reviewer: AhmadLX (talk · contribs) 17:10, 7 April 2021 (UTC)

Misc.

• "Rest mass, also called invariant mass, is the mass that is measured when the system is at rest." --> "...that is measured in the rest frame"? "is at rest" is not clear enough.
• "which is on the order of 10¹⁹ joules for a mass of one kilogram.": 10¹⁷ joules I suppose. [somebody fixed this already]
• "Due to this principle, the mass of the atoms that come out of a nuclear reaction is less than the mass of the atoms that go in, and the difference in mass shows up as heat and light with the same equivalent energy as the difference." There is nothing preceding this sentence that would warrant "Due to this principle". First state, with reference, that mass and energy are interconvertible and that such conversion is quantified by this equation.
• "In analyzing these explosions, Einstein's formula can be used with E as the energy released and removed, and m as the change in mass." This "in these explosions" is childish language. Moreover, not all nuclear reactions are "explosions". This looks like part of a high school assignment submission.
• "In relativity, all the energy that moves with an object..." Energy "moves" with an object? Replace with something like "all the energy contained by an object".
• "Because the relativistic mass is exactly proportional to the relativistic energy, relativistic mass and relativistic energy are nearly synonymous; the only difference between them is the units". This is treated in a bit more detail down below (in section Relativistic mass). Should be removed from here.
• There is significant overlap of content b/w Relativistic mass and Conservation of mass and energy. Should be combined into one section and repetition removed.
• "For closed systems made up of many parts, like an atomic nucleus, planet, or star, the relativistic energy is given by the sum of the relativistic energies of each of the parts, because energies are additive in these systems. If a system is bound by attractive forces, and the energy gained in excess of the work done is removed from the system, then mass is lost with this removed energy." I find this contradictory. First sentence says energy of, say, a nucleus is sum of its constituents. The latter says the opposite.
• "Such conversions between types of energy happen in nuclear weapons, in which the protons and neutrons in atomic nuclei lose a small fraction of their original mass, though the mass lost is not due to the destruction of any smaller constituents." Do protons and neutrons really lose mass? Are you saying that the nucleons making up the daughter nuclei are lighter than those of the parent? Also, "though the mass lost is not due to the destruction of any smaller constituents" bit contradicts the preceding part of the sentence anyway.
• Section "Efficiency" should be renamed, as efficiency is very misleading. Does the equation have an associated efficiency? Also, the discussion under it is basically potential total conversion. It should be made a sub-section of "Applications" and could then be named something like "Potential applications", or "Total conversion of mass into energy" etc.

Sourcing and citations

• A lot of stuff is uncited (para 1 of Description, last lines in Mass in special relativity, entire section Massless particles, a couple things in Composite systems, whole first para and more than half of the second para in Relation to gravity, a couple lines in the last para of Efficiency, some points in Extension for systems in motion, Application to nuclear physics, Practical examples, Developments prior to Einstein, and it goes). Citations are required for technical stuff. Only obvious claims don't need citations. If this is not addressed, the nom will fail.

• "though experiments have shown an object's gravitational mass depends on its total energy and not just its rest mass.^{[citation needed]}" Please have a look into the provided rationale.

• "As it is just another name for the energy, ... as opposed to relativistic mass.[12][13]" Neither source (on the cited page) supports this claim. I think you've cited wrong page numbers.

Copyvio

Earwigs' shows a couple matches, but they are to be disregarded (see below). So copyvio is okay.

• This blog has copied material from Wikipedia without attribution. Material on Wikipedia predates the blog publication date-July 26, 2014.
• Match with this Stanford page is basically paper names, technical terms and some common phrases (e.g. "the speed of light", "Equivalence of Mass and Energy", "kinetic energy", "Standard Model" etc.).
• Match with this page is to be disregarded. Although no date of the publication of the page is given, examination of the page shows that the dudes doing homework certainly copied material from Wikipedia without attribution.
• Other matches are insignificant and are basically like the Stanford page match.

Broadness Okay.

Images

All fine. A couple points added below for the record.

• File:Einstein - Time Magazine - July 1, 1946.jpg : Valid fair use rationale has been provided on the file page.
• File:E mc 2 IMG 0859.jpg : Source unknown, but I am willing to accept the PD claim, given it is so old.

Good Article review progress box

Criteria: 1a. prose () 1b. MoS () 2a. ref layout () 2b. cites WP:RS () 2c. no WP:OR () 2d. no WP:CV () 3a. broadness () 3b. focus () 4. neutral () 5. stable () 6a. free or tagged images () 6b. pics relevant () Note: this represents where the article stands relative to the Good Article criteria. Criteria marked are unassessed

Hi, I hope to have time to work on this in the next week or so, I have not been on here in a while and am behind. So I agree with a lot of your points, the main deal is that I was a relatively new editor to the page and it didn't seem appropriate for me to gut everything, so I had to pick and choose which things I really needed fixed and I left the other stuff for others to deal with. Also, I am sure there are several references that need to be added in, especially when it comes to things like the history section, but overall, please see WP:Scientific citation guidelines which states that statements such as "A frustrated spin glass may have a large ground state degeneracy." require no citation because they are "widely known among people familiar with a discipline". Most of the stuff you mention needs citations is known to all physicists and therefore does not need a citation; it can in fact be referenced to any introductory physics book, but there is no need for Wikipedia editors to suggest which of these introductory textbooks is best for the reader, that is a job for reddit. As I said, I will read everything over and try to work on it soon, it has been months though, so it may take a bit. Footlessmouse (talk) 05:07, 11 April 2021 (UTC)

@Footlessmouse: excited to see you've taken up this core article. I've done some gnoming to help this nomination along (hopefully). I've got a few additional comments:

• A water molecule weighs a little less (...): this paragraph is quite long for what it tries to explain. Can you shorten it?
• There were several further developments (...) this paragraph is difficult to read to due all it's double-lined equations. Maybe you can use the / as a division sign instead.
• In footnote 5, a unit is needed: Cp of 25.9
• Otto Hahn's experimental results -> Hahn hasn't been introduced. Even though Meitner had fled to Sweden at this point, she was still heavily involved in the design of the experiment, so given all credit to Hahn is probably not fair.

I've not looked into the specifics of the citations, but when not to cite includes the 'laypersons' familiar with a discipline. As a physics graduate with a different specialization, I fall in that category, so can give a second opinion on the matter if you want. FemkeMilene (talk) 17:54, 11 May 2021 (UTC)

Thanks Femkemilene for the comments. I hope they get addressed. I should add that the policy page has not been cited correctly. The page does not say that "frustrated glass" bit does not need citation. It says that it, and any other similar thing, does need citation. The only difference here is that a single citation per paragraph should suffice (if the paragraph contains only such common knowledge). Given that, a text-book reference, which according to Footlessmouse is no big deal to find, should be added to the end of each paragraph. Where things are not so common knowledge, denser citations will be required. AhmadLX-(Wikiposta) 20:13, 11 May 2021 (UTC)

I was unaware of Wikipedia:Scientific citation guidelines, talking instead about Wikipedia:When to cite, which says: Subject-specific common knowledge: Material that someone familiar with a topic, including laypersons, recognizes as true. Example (from Processor): "In a computer, the processor is the component that executes instructions." Either way, I've not looked into sourcing for this article. FemkeMilene (talk) 20:49, 11 May 2021 (UTC)

• @Femkemilene: Hi. Would you mind carrying this review from here? I don't see myself being active again this year :/ Thank you :) AhmadLX-(Wikiposta) 10:54, 30 May 2021 (UTC)

  A shame you're taking a wikibreak. Hope you're coming back soon :). I can take over this review. As it's going quite slow, I hope my own business won't slow the review.

  User:footlessmouse: you've not been active since April 11. Are you planning to pick this up again? FemkeMilene (talk) 17:10, 30 May 2021 (UTC)

  User:footlessmouse: I will fail the article due to not meeting prose and maybe original research if I don't hear from you soon. I would really like for this article to become GA, so hope you nominate again if you're too busy now. FemkeMilene (talk) 13:54, 13 June 2021 (UTC)

Review FM

Good Article review progress box

Criteria: 1a. prose () 1b. MoS () 2a. ref layout () 2b. cites WP:RS () 2c. no WP:OR () 2d. no WP:CV () 3a. broadness () 3b. focus () 4. neutral () 5. stable () 6a. free or tagged images () 6b. pics relevant () Note: this represents where the article stands relative to the Good Article criteria. Criteria marked are unassessed

Prose:

• Maybe you can split 'Einstein's equation written' into a section on 'cultural impact'? The subsection title is unclear to me.

Reliable sources

• I'm a bit worried about the quantity of primary sources cited. Ideally, you'd like more modern secondary sources. If this were a FA nomination, this wouldn't fly, but the standards at GA are lower. Can you convince me that the alternative version has due weight?
• Is In Einstein's more physical, as opposed to formal or mathematical, point of view, there was no need for fictitious masses. He could avoid the perpetual motion problem because, on the basis of the mass–energy equivalence, he could show that the transport of inertia that accompanies the emission and absorption of radiation solves the problem. Poincaré's rejection of the principle of action–reaction can be avoided through Einstein's E = mc2, because mass conservation appears as a special case of the energy conservation law. all cited to Einsteins paper: again, a modern source would be preferable.
• Note 5 needs a citation.