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"Plasma"

The usage and primary topic of "plasma" is under discussion, see talk:plasma (physics) -- 70.51.46.39 (talk) 05:51, 11 March 2016 (UTC)

Negative mass?

User:Guanghuilin has been editing articles like Momentum, Energy–momentum relation, Kinetic energy, Dark energy, Abraham–Minkowski controversy, Momentum operator, Tachyon, and Faster-than-light.

Is this notable or fringe (or even both)? M∧Ŝc2ħεИτlk 11:27, 23 February 2016 (UTC)

The momentum operator edit is annoying insofar as they just added a section called "self-adjointness" just a few paragraphs below a section we already had about Hermiticity (which means exactly the same thing), and the two redundant sections are contradicting each other.
I don't have access to the newly-added references right now so I can't reconcile them, but will later. --Steve (talk) 13:48, 23 February 2016 (UTC)
I just deleted the section. Even if somebody constructed a quality paper in which it is not self-adjoint, it is not sufficiently notable for this article. Perhaps a separate article based on that paper (if it exists)? That's my opinion. --Guy vandegrift (talk) 16:12, 23 February 2016 (UTC)
Thanks. All the user's edits should probably be checked. M∧Ŝc2ħεИτlk 21:57, 23 February 2016 (UTC)
The claims
look questionable.
Overall, the very concept "negative mass" is already questionable. It may be of theoretical interest, but so far it has never been observed. So the topic must be fringe? M∧Ŝc2ħεИτlk 22:41, 23 February 2016 (UTC)
There is loads of things that are of theoretical interest, have never been observed, and are not fringe. (Gravitational waves up to 14 september 2016 would be one of them). Although negative mass is general problematic, it is not necessarily fringe as a concept. (I have published papers featuring negative mass in the past.) That being said there seems to be some fringe pushing going on here.TR 12:43, 24 February 2016 (UTC)
I didn't mean to imply unobserved concepts are automatically fringe (though it may look that way). Still, I'm not sure why adding modified formulae for negative mass is helpful. If there is an article on negative mass (which there is), then all modified formulae should probably be there in one place, with "see also" links in other articles. M∧Ŝc2ħεИτlk 16:38, 25 February 2016 (UTC)

Tachyons, if they existed, would have imaginary (not negative) mass. 'Exotic matter' as he describes it at Energy-momentum relation#Tachyon and Exotic matter would violate the Lorentz covariance of special relativity. JRSpriggs (talk) 09:59, 24 February 2016 (UTC)

Which is not necessarily a problem when discussing a metamaterial, since Lorentz variance will be broken by the materials rest frame anyway. Weird exotic dispersion relations certainly can occur. TR 12:47, 24 February 2016 (UTC)
Yes, I meant to say "exotic matter" has negative mass, and tachyons have imaginary mass, last post was rushed and unclear. M∧Ŝc2ħεИτlk 16:38, 25 February 2016 (UTC)

Note: I undid ([1]) a new addition of same at Mass–energy equivalence, requesting secondary sources. - DVdm (talk) 10:55, 11 March 2016 (UTC)

Hey, I just noticed that the Negative mass article does not seem to have a link to Effective_mass_(solid-state_physics), which is 100% bona-fide (though not a fundamental property of nature). The use of negative mass in solid state physics is analogous to the use of "tidal forces" or that inertial pseud0-force that throws you to the front of a car when the brakes are on. During an accident you don't really care why you are suddenly thrown into the windshield.--Guy vandegrift (talk) 15:32, 11 March 2016 (UTC)

Blatant violation of manners

I think hijacking a comment of one contributor by an other as demonstrated here, is highly inappropriate and should be dealt with, perhaps up to some formal warning. Purgy (talk) 08:00, 15 March 2016 (UTC)

I don't see any hijacking here. Just Staszek Lem responding to two messages from Asterixf2, adding a remark and moving down another remark, fixing its indentation in the process, going from this to this (compare in two tabs). Seems in line with wp:TPG and wp:THREAD and wp:INDENT example #3. - DVdm (talk) 08:47, 15 March 2016 (UTC)

I apologize for having sloppily misread the insertion of a comment outside of the time line in the history display as highjacking of a previous comment. Purgy (talk) 12:25, 15 March 2016 (UTC)

The "diff tool" is far from perfect, so it is an understandable mistake. YohanN7 (talk) 12:38, 15 March 2016 (UTC)

Possible fringe or nonsense at Entropic force

Could someone have a look at what's going on at Entropic force (and Entropic gravity, [[]]) please? A brandnew (?) user Asterixf2 (talk · contribs) is adding poorly sourced fringe, clearly against consensus on talk Talk:Entropic force#MET. See also warnings at [2], now erased. Also seems to sort of retaliate on user talk pages: [3] and [4]. - DVdm (talk) 16:55, 9 March 2016 (UTC)

Please do not misrepresent what actually happened, since I started the discussion on MET (only this was discussed) I have not added this topic again even once to the article and furthermore I have clearly stated twice in discussion Talk:Entropic force#MET that I am giving it a pause. Therefore, writing that I did it "clearly against consensus" is a misrepresentation. Also imo you are not precise enough when talking about changes and you started to diffuse discussion about Talk:Entropic force#MET by writing there about your revert of my changes that were not concerned with MET but you probably failed to notice that (assuming WP:GOODFAITH). Perhaps you should be more careful with your reverts/comments. Please see WP:DONTBITE --Asterixf2 (talk) 18:20, 9 March 2016 (UTC)
Aterixf2, you seem to have learned wikipedian alphabet soup quite well. Now time to read and understand out basic policies about article content. Staszek Lem (talk) 19:55, 10 March 2016 (UTC)
... and about wp:talk page guidelines and changing other people's comments: [5]. - DVdm (talk) 19:58, 10 March 2016 (UTC)
Thank you for escalating my vandalism, especially for the vandalism that you pointed out on my talk page by referring it with this link in this revision on my talk page. I apologize for this severe vandalism. --Asterixf2 (talk) 20:16, 10 March 2016 (UTC)
No problem. Just keep it in mind. From our own talk page we can remove (almost) everything we want, but we don't touch other people's comments on other talk pages. - DVdm (talk) 20:33, 10 March 2016 (UTC)
Thank you for your guidance. Please also see Wikipedia:Avoid the word "vandal" and Wikipedia:Assume good faith. --Asterixf2 (talk) 17:23, 14 March 2016 (UTC)
To get back to the substance here. The phrase 'entropic force' is at best a metaphor. It needs some care and subtlety to unpack it, from someone with deep understanding of the topic. The topic cannot be usefully tackled by editors who are not adequately equipped to deal with it. Better delete the whole article than that.Chjoaygame (talk) 12:20, 14 March 2016 (UTC)
What the hell are you talking about? How is "entropic force" a metaphor? TR 13:02, 14 March 2016 (UTC)
The language of the immediately foregoing comment is unseemly. It does nothing for its credibility. The phrase 'entropic force' is self-avowedly interpretive, not a direct use of the word entropy in its ordinary sense. Broadly speaking, entropy is in contrast with force in the sense of macroscopic thermodynamics. The 'forces' are responsible for quasi-static work, and entropy and temperature together account for dissipated energy transfer. To speak of an 'entropic force' is to directly challenge this. We are witnessing what on the face of it is an attempt by various workers to create a new topic, and source of opportunity for publication, that relies on a metaphoric, even oxymoronic, combination of the words 'entropy' and 'force'. The forces of thermodynamics are primarily macroscopic, not considered in microscopic terms. The article Entropic force discards this basic idea of thermodynamics without a blink. Such is not good Wikipedia editing. The topic is subtle and calls for subtle editing, that so far is not evident the article.Chjoaygame (talk) 02:40, 15 March 2016 (UTC)
An entropic force, is a force that is driven by changes in entropy rather than potential energy. There is no metaphor here. This is fairly standard physics, and there is a vast literature on it. By their very nature entropic forces are always emergent macroscopic phenomena with no direct microscopic interpretation, that does not make them any less real. In the end entropic forces are what allow you to do work using thermal energy. It is your notions of what 'forces' and 'entropy' are that are atypical and antiquated.TR 08:52, 15 March 2016 (UTC)
Agree with TR by and large, although I do think it has a direct microscopic interpretation, in the following sense. If I have stretched a rubber band, most of the random thermal fluctuations in the rubber band are exerting a force that tries to retract the rubber band, while only a small fraction of the random thermal fluctuations are exerting a force that tries to extend the rubber band. When you average over many random thermal fluctuations, there is a net tensile force.
I definitely agree with TR that neither "entropic" nor "force" are metaphorical, and that this concept is an accepted part of mainstream physics and physical chemistry. --Steve (talk) 14:05, 15 March 2016 (UTC)
Of course, the second law of thermodynamics always has some statistical microscopic interpretation. By "no direct microscopic interpretation" I simply meant that there is no property at level of the individual microstates that would tell you that the macroscopic force exists. This only becomes apparent after averaging over the ensemble (and is dependent on the density of states on that ensemble).TR 14:42, 15 March 2016 (UTC)
It seems DVdm and Staszek Lem need to seriously re-read of WP:BITE. Looking at the edit history I see a clear case of a new editor providing clearly good faith (and fairly good quality) contributions, that is getting pounced upon be two very experienced editors that should have handled the situation much better, and at this stage should offer their apology for there rather rash misjudgement of the situation. Of course that is my humble opinionTR 13:14, 14 March 2016 (UTC)
This was my first message to this user. No response. And no response until after a 3RR warning following a third level warning. Did I misjudge this link as nonsense? - DVdm (talk) 13:31, 14 March 2016 (UTC)
Instead of initiating a BRD cycle on the talk page you proceeded straight to issuing warnings, which is the opposite of being welcoming. Although you are right that that link is nonsense most of his other edits to the entropic force page appear good. Note that after the addition of that link was reverted twice he never re-added it. Yet, you persisted in blanket reverting his edits, without ever entering into discussion on the talk page. Note that he also never broke 3RR.
The evidence here is that you massively over reacted to a new editor that was trying to be constructive. Instead if aggressively issuing a succession of boiler plate warnings, it probably would have been much more constructive if you simply started a talk page thread. (It would have been even better if he would have started a thread after the first revert, but he's new and you have been around for ages.)TR 15:38, 14 March 2016 (UTC)
Fair enough. My ages-old nonsense allergy made a bit overwary and needlessly suspicious. Asterixf2, I owe you an apology. I am sorry for the biting. Timothy, thanks for your effort. - DVdm (talk) 15:59, 14 March 2016 (UTC)
This is very simple DVdm. My response, contrary to what you suggest, was to create a discussion on talk page just after your first revert in which you suggested to do so. Later, you were reverting other changes not related to this link. I am getting tired of your misrepresentations. I have never added again MET section to the article after creating discussion on talk page. --Asterixf2 (talk) 17:14, 14 March 2016 (UTC)
sighTR 17:29, 14 March 2016 (UTC)
User Staszek Lem have just deleted, in my opinion, valuable content from the article. Deleted sections were not created by me, but they were there for around 3 years (I have checked history) and the deleted content was not about MET that is discussed on talk page. In my opinion this was a valuable content. Definitely of interest to someone researching 'entropic forces' and with due weight as they were in a section 'controversial'. Diff: Removal of 'other forces' by Staszek Lem.
Also I would like to point out again that the concept was previously subtly ridiculed by its content. Therefore content created by some editors violated wp:npov and wp:notcensored. --Asterixf2 (talk) 17:56, 14 March 2016 (UTC)
The content was deleted per WP:FRINGE. It does not matter how long bad content sits in the article. My explanation was in article talk page, ignored by Asterixf2, as follows: due weight of fringe theories is judged by its coverage in independent sources, not by opinions of wikipedians. See Wikipedia:Fringe theories: " For a fringe view to be discussed in an article about a mainstream idea, reliable sources must discuss the relationship of the two as a serious and substantial matter.". See Wikipedia:Fringe theories#Unwarranted promotion of fringe theories for more detail. Staszek Lem (talk) 18:31, 14 March 2016 (UTC)
It does matter. If it was there for 3 years there was a kind of consensus. Independently of that, you do not have consensus to delete this content. WP:NOCONSENSUS In deletion discussions, a lack of consensus normally results in the article, page, image, or other content being kept.. Last but not least, I am really surprised that you state that I have ignored sth. --Asterixf2 (talk) 20:50, 14 March 2016 (UTC)
Staszek Lem reverted now my revert of his deletion of "Other forces" in "Controversial" - subsection that was there 3 years. I am confused. Shouldn't he get consensus for deletion in such case? What are the guidelines? --Asterixf2 (talk) 21:12, 14 March 2016 (UTC)
You do not need consensus to delete dubious text. I cited you a clear guideline in this respect, twice. Staszek Lem (talk) 21:35, 14 March 2016 (UTC)
Yes, you do not need consensus to delete dubious text, but once your BOLD deletion was FIRST REVERTED you should discuss. In my opinion, that is what both Wikipedia:BOLD, revert, discuss cycle and WP:NOCONSENSUS In deletion discussions, a lack of consensus normally results in the article, page, image, or other content being kept say. --Asterixf2 (talk) 17:32, 15 March 2016 (UTC)

Possible historical oversight on quark discoverers

Please comment at Talk:Quark#André_Petermann. This concerns a potentially a major historical oversight when it comes to who proposed the existence of quarks. Headbomb {talk / contribs / physics / books} 15:31, 18 March 2016 (UTC)

Cryo-scanning electron microcopy

I started an article, now a draft, on Cryo-scanning electron microscopy, but it was rejected because I left a note for the reviewer to upload an image. I used to do this when Wikipedia first moved to AFC, and started not allowing IPs to create articles, and it worked well, but now it seems it is just button pushers at AFC, and this did not work the last couple of times.

Would someone at this project please upload a CC Plos ONE image to Commons to add to the article? Figure 6 from http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0113336, with the image caption, "Cryo-scanning electron microscopy was used to capture this micrograph of the laticifers or latex producing cells in the leaves of a Campanula glomerata plant." I found some better ones, but I just wanted an image to start the article.

If you upload the image, I will add it to the article, or you can. As there was nothing wrong with the article it should be moved to mainspace soon enough whether you choose to or not. A little additional editing would not hurt, though. There are plenty of great on-line sources.

Thanks for your help. 2600:380:985F:CE86:907F:40C4:452D:8F8F (talk) 14:54, 13 March 2016 (UTC)

Just taking the picture from the article may not be ok for copyright reasons. You have to check the license first. It is also questionable if a separate article is needed at all. There is already a rather similar test includes under scanning electron microscope#Biological_samples.--Ulrich67 (talk) 20:08, 19 March 2016 (UTC)

Heisenberg and spin waves

This edit has just categorised these under Category:Werner Heisenberg. Is that justified? They're not one of Heisenberg's better known discoveries, but then nor are they my field. Thoughts?

I have concerns mostly because of the new editor bulk-creating categories like this, who has a strong behavioural similarity to a problematic sockmaster, Europefan. Much of the trouble there was due to a serious disregard for accuracy or sourcing when pushing his agenda. Andy Dingley (talk) 11:37, 22 March 2016 (UTC)

Thanks for letting us know. It looks like the addition has been reverted and I agree with the reversion. There are spin waves in the Heisenberg model (quantum) (and in many other spin models), but these are typically not called Heisenberg spin waves. Hence Heisenberg couldn't be considered a defining characteristic of spin waves. --Mark viking (talk) 19:54, 22 March 2016 (UTC)

Category:Optical devices and Category:Optical instruments

Category:Optical devices has been proposed to be merged into Category:Optical instruments; for the discussion, see Wikipedia:Categories_for_discussion/Log/2016_March_21#Category:Optical_devices -- 70.51.46.39 (talk) 06:03, 24 March 2016 (UTC)

Need to roll-back edits

Someone with the authority to roll-back multiple edits should look at 96.230.106.141 (talk · contribs · WHOIS) who has been removing valuable information with excuses such as that action is not angular-momentum therefore one should not mention that they have the same units. JRSpriggs (talk) 17:04, 24 March 2016 (UTC)

Three articles for reference
The articles do not state that angular momentum and action, and torque and energy, have the same unitsare the same or related quantities. The IP assumes the articles are. M∧Ŝc2ħεИτlk 17:31, 24 March 2016 (UTC)

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Strange things at Minimum total potential energy principle

Holiness? By increasing the world's debt (i.e., the world's synergy) the bankers are indeed "doing God's job" ? Can someone please have a look at what this IP (first as 89.110.16.26, now as 89.110.1.39) is doing here? I have reverted the most obvious and gave some warnings, but I'm afraid this is not going to help much. This could use some more eyes and hands. Thx. - DVdm (talk) 20:33, 22 March 2016 (UTC)

I got the article semi'd for a week at WP:RPP. Right now I think the article is WP:WEIGHTed incorrectly but there's nothing wrong or irrelevant to physics in it right now. --Izno (talk) 13:01, 25 March 2016 (UTC)
All the recent edits seem to come a familiar St.-Petersburg source. See:
Article is now temporarily semi-protected by AlexiusHoratius. Content restored by Izno and David.moreno72, thx.
I had sort of a chat with current ip 89.110.8.55 (talk · contribs) at my talk: User talk:DVdm#Minimum total potential energy principle
Looks like long term abuse. - DVdm (talk) 13:14, 25 March 2016 (UTC)
Yeah, I agree, this is an LTA. --Izno (talk) 13:47, 25 March 2016 (UTC)
By the way, Izno, part of what you removed here, was accidentally reinserted by David.moreno72 here. You might want to re-re-re-remove . - DVdm (talk) 13:32, 25 March 2016 (UTC)
And now I've nuked a bit more. --Izno (talk) 13:47, 25 March 2016 (UTC)
Nuked? You are more like a rotten puffball than a nuke:
—89.110.8.55 (talk) 13:53, 25 March 2016 (UTC)
I don't even know what that looks like. A tribble? --Izno (talk) 14:04, 25 March 2016 (UTC)
The edits in the end seems unrelated to the topic of Minimum total potential energy principle anyway. When a star loses mass, does it move from a state of minimum total potential energy, to another state of minimum total potential energy. No. The formula (which was slightly wrong anyway), is for Gravitational Potential Energy, which, yes, decreases over a stars lifetime. When this gravitational potential energy reaches close to a minimum, snd so reaches minimum total potential energy, is when the star has collapsed to form a neutron star. The problem with the edits as I see it is that they became disruptive. How many times did it take to get a citation? Too many. And the citation that was provided https://books.google.co.uk/books?id=msZMEvEpxG8C&pg=PA29#v=onepage&q&f=false did not mention Minimum total potential energy whatsoever, but was instead about gravitational potential energy, a different topic, which btw is represented on two different Wikipedia pages. The edits would have been better suited to the gravitational potential energy page. The other problem is when the editor said 'You will never become an administrator)' in the edit comment. That sort of behaviour is appalling, and I doubt there will be any good faith after that. David.moreno72 (talk) 14:08, 25 March 2016 (UTC)
At the end of a star's evolution, its nuclear binding energy becomes ever less negative and eventually becomes zero. How is it compatible with the minimum total potential energy principle? The answer is simple: when we are talking about the total potential energy, we are talking about the gravitational potential energy. All other forms of potential energy are transiently concomitant and can be ignored. —89.110.8.55 (talk) 14:34, 25 March 2016 (UTC)
I had a look at the edits that izno removed. A google search as a reference??? Where have I seen that before?? Oh that's right, here http://en.wiki.x.io/w/index.php?title=Gravity&diff=711516152&oldid=711515856 And they are ALSO talking about gravitational potential energy. Also from Saint Petersburg. A coincidence? Or a sock? My bet is on a sock. David.moreno72 (talk) 14:26, 25 March 2016 (UTC)
Yes, see Wikipedia sockpuppets of Antichristos and Suspected Wikipedia sockpuppets of Antichristos. - DVdm (talk) 14:36, 25 March 2016 (UTC)
Since the universe is holographic, you guys are just a few of my seven-plus billion socks. —89.110.8.55 (talk) 14:47, 25 March 2016 (UTC)
Spi case filed. - DVdm (talk) 14:58, 25 March 2016 (UTC)
There is nothing to investigate. The universe is holographic, and you guys are my stinking socks. —91.122.3.230 (talk) 15:44, 25 March 2016 (UTC)

"Dynamic instability"

Dynamic instability has been nominated for deletion at RFD -- 70.51.46.39 (talk) 03:27, 29 March 2016 (UTC)

Guidelines about living scientists

See Wikipedia_talk:WikiProject_Biography/Science_and_academia#guidelines_about_living_scientists--Alexmar983 (talk) 04:57, 30 March 2016 (UTC)

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