Wikipedia talk:WikiProject Physics: Difference between revisions
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::Hi Richard, I noticed that ref #2 returns a missing page. Since you are already on the subject, here is a new link that works http://www.its.caltech.edu/~qoptics/ph135b/Bell-inequalities_v2_r.pdf . Hope this helps! [[User:Almaionescu|Alma]] ([[User talk:Almaionescu|talk]]) 10:15, 23 December 2013 (UTC) Actually maybe I can revise the references and point them to online sources (as many of them are offline sources right now) so you won't waste time with that. What do you think? [[User:Almaionescu|Alma]] ([[User talk:Almaionescu|talk]]) 10:24, 23 December 2013 (UTC) |
::Hi Richard, I noticed that ref #2 returns a missing page. Since you are already on the subject, here is a new link that works http://www.its.caltech.edu/~qoptics/ph135b/Bell-inequalities_v2_r.pdf . Hope this helps! [[User:Almaionescu|Alma]] ([[User talk:Almaionescu|talk]]) 10:15, 23 December 2013 (UTC) Actually maybe I can revise the references and point them to online sources (as many of them are offline sources right now) so you won't waste time with that. What do you think? [[User:Almaionescu|Alma]] ([[User talk:Almaionescu|talk]]) 10:24, 23 December 2013 (UTC) |
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=="{{noredirect|Aeronautics}}"== |
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FYI, {{la|aeronautics}} has been proposed to be merged into [[aviation]], see [[talk:aviation]] -- [[Special:Contributions/65.94.78.9|65.94.78.9]] ([[User talk:65.94.78.9|talk]]) 23:24, 23 December 2013 (UTC) |
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Proton/Neutron structure image
AspaasBekkelund (talk · contribs) has been changing our current images for baryon structure from
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to |
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and
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to |
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Since these would affect a large number of high-visibility articles, I revert them so we could discuss if this was appropriate or not. I don't have any strong qualified opinion either way, although it do think the older image looks nicer. Also if we choose the new version, we should probably update the current image rather than create a new one. Headbomb {talk / contribs / physics / books} 11:39, 14 November 2013 (UTC)
- I had a discussion with my particle physics professor, who says that the images on the left are better to describe a baryon. This is because the quarks directly interact with each other. Truth be told, neither of the images describes what actually happens, but the image on the left is more indicative of the interactions between quarks. In the right image, it gives the impression that the quarks are releasing gluons into a general space, when in fact the quarks are interacting with each other via gluon transfer. Primefac (talk) 13:01, 14 November 2013 (UTC)
- That was my impression as well, although I can't claim much expertise here. I think the y-shape for the gluon is sort of based on the shape of the gluon flux tubes (e.g., see figs in arXiv:hep-lat/0606016 / arXiv:hep-lat/0212024 / arXiv:hep-lat/0401026), but that is a far stretch from saying that the interaction is not quark-gluon-quark, but rather quark-gluon-gluon-quark. Headbomb {talk / contribs / physics / books} 14:00, 14 November 2013 (UTC)
- I will have to defer to experts in the field, about whether the 'delta' formation on the left or the 'y' formation on the right is more accurate. (Although it is my impression that they are both equally bad and there is probably no good way to represent what is actually happening.) I prefer the aesthetics of the right since it is easier to read the letters. However, I do prefer the lighter gray circle with the less distinct boundary since it distracts less from the up and down quarks with their gluon interaction. Further, I don't want to cause more trouble, but shouldn't the gluons have color as well?
This will be a short response since I have to leave soon, but I will come back for more discussions soon. I can agree that the previous image might look nicer, but I don't feel it shows how the gloun flux tubes is connected. Since with a still image it is very hard to represent what's actually happening, I would like to create a .gif instead which will make it easier to show what is happening. Something like what Hank Green has done in this video(starting at 2:30). What are your thoughts on that?
Thanks for the feedback - AspaasBekklund (talk) 14:43, 15 November 2013 (UTC)
- Why do you feel its important to illustrate the 'flux tubes'? Do you beleive that the Y configuration has a bigger amplitude than the delta configuration? Perhaps it illustrates confinement better, or helps explain the origin of jets? User:Linas (talk) 22:09, 30 November 2013 (UTC)
I just did a major rewrite of our article on the Wu experiment (which established P-violation) old version. It's a very interesting topic/experiment, but it would be nice if someone could double-check if I got anything wrong/if I muddied the waters. I've trimmed lots of materials and details from the old version, mostly because it was either unclear or had the effect of hiding a forest behind trees (i.e. mundane details). The mechanism and consequences section is the one which I feel needs the most attention from someone who can handle the mathematics of P-violation/weak interaction.
If you have sources for the various [citation needed], feel free to add them. Headbomb {talk / contribs / physics / books} 05:54, 18 November 2013 (UTC)
- Did some copyediting, most relatively non-controversial, but deleted a sentence that seemed vaguely gobbledegook to me:
- "The gamma rays are emitted electromagnetically, and are quickly released from the excited Nickel-60 nucleus."
- What in heck does it mean for gamma decay to occur "electromagnetically"? Thanks. — Preceding unsigned comment added by 173.57.52.219 (talk) 12:43, 24 November 2013 (UTC)
- Gamma rays are photons. Since photons are the mediators of the EM interaction, gamma decay is an EM process. I've restored the sentence. Headbomb {talk / contribs / physics / books} 13:35, 24 November 2013 (UTC)
- Does it add anything to the experimental description to state that emission occurs "electromagnetically"? Is there any non-electromagnetic means for gamma emission to occur? Does it not strike you that the sentence is totally redundant?
- Gamma rays are photons. Since photons are the mediators of the EM interaction, gamma decay is an EM process. I've restored the sentence. Headbomb {talk / contribs / physics / books} 13:35, 24 November 2013 (UTC)
- Note that almost immediately before the statement under question, one reads "The stable nickel nucleus is excited by the reaction and emits two gamma rays (γ)..." So what does the statement under question add except the need for the reader to scratch his head trying to figure out its intent? — Preceding unsigned comment added by 173.57.52.219 (talk) 14:22, 24 November 2013 (UTC)
- The "Experiment" section is unclear. It needs an illustration. Anybody care to make an English version of File:Parity violation principle Wu experiment.jpg so that it can be added to the article? — Preceding unsigned comment added by 173.57.52.219 (talk) 14:12, 24 November 2013 (UTC)
- That gamma decay is an EM process is important because EM does respect P-conservation. This is why comparing beta decay with gamma decay yield information about whether or not beta decay respects P-conservation or not. The information is technically redundant, in that this is obvious to who understands the physics of gamma decay, and know that gamma rays = photons, and that photons mediate the EM interaction. But this needs to be spelled out because this isn't something that's obvious to someone who isn't familiar with particle physics.
- A reworded version of what you've just written would be an excellent addition to this section. 173.57.52.219 (talk) 14:44, 24 November 2013 (UTC)
A quite well-written description of the Goldhaber Experiment is available on the German Wikipedia. Anybody care to take a hand at translating it? 173.57.52.219 (talk) 07:47, 25 November 2013 (UTC)
- It's on my to do list at some point in the mid-to-near future (i.e. before 2015), but one thing at a time. Feel free to create the article yourself btw. If you don't want to register, you can follow WP:AFC. Headbomb {talk / contribs / physics / books} 17:51, 25 November 2013 (UTC)
I find the following statement to be disturbing: "The parity violation observed in this experiment resulted from the W and Z gauge bosons of the weak interaction only interacting with left-handed matter particles and right-handed antimatter particles." Is this statement true for the Z boson? 173.57.52.219 (talk) 08:05, 25 November 2013 (UTC)
- In the case of the Standard Model, the answer would be no since right-handed matter neutrinos simply don't exist. In the case of Standard Model extensions, the answer would depend on the model. One way or another though, the Z boson is not involved in beta-decay at all, so the statement in question seems a bit muddy to me. Stigmatella aurantiaca (talk) 12:05, 28 November 2013 (UTC)
Please check my "Materials and methods" description. Thanks. 173.57.52.219 (talk) 11:34, 28 November 2013 (UTC)
Cleanup listing out of date
The pages Wikipedia:WikiProject Physics/Cleanup listing, Wikipedia:WikiProject Physics/Taskforces/Acoustics/Cleanup listing, and so on, may have been very useful in their time, but are now three years out of date. The automatically generated CleanupListing fills much the same role and is always nearly up to date. Yet multiple links to the former are prominently displayed on the project page while a link to the latter is tucked away at the bottom. Is it time to get rid of the old pages and display the CleanupListing box more prominently? RockMagnetist (talk) 17:31, 20 November 2013 (UTC)
Another collection of obsolete pages is Wikipedia:Pages needing attention/Classical physics and other lists of pages needing attention. Some have been marked with a {{historical}} tag, but such a tag is really intended for old policies and guidelines (see WP:HISTORICAL). RockMagnetist (talk) 18:43, 20 November 2013 (UTC)
- We could just delete the redundant stuff. Headbomb {talk / contribs / physics / books} 14:46, 24 November 2013 (UTC)
One other issue: on some of the taskforce pages there are new article alerts like this one linking to pages of a blocked user. Can these be replaced by functional alerts, or should they just be deleted? RockMagnetist (talk) 18:26, 28 November 2013 (UTC)
Plasma
I'm not a professional scientist, so someone might review my edit. 2601:8:B500:862:DDBE:B5D5:2AD5:B5CC (talk) 16:18, 27 November 2013 (UTC)
- Your instincts were right. Thanks for your removal of hyperbole! Stigmatella aurantiaca (talk) 17:02, 27 November 2013 (UTC)
- Amazing. That article had an Unreferenced tag dating back to 2008. RockMagnetist (talk) 17:13, 27 November 2013 (UTC)
![](http://upload.wikimedia.org/wikipedia/en/thumb/7/74/Ambox_warning_yellow.svg/48px-Ambox_warning_yellow.svg.png)
The article Universality and Quantum Systems has been proposed for deletion because of the following concern:
- see talk page there...
While all constructive contributions to Wikipedia are appreciated, content or articles may be deleted for any of several reasons.
You may prevent the proposed deletion by removing the {{proposed deletion/dated}}
notice, but please explain why in your edit summary or on the article's talk page.
Please consider improving the article to address the issues raised. Removing {{proposed deletion/dated}}
will stop the proposed deletion process, but other deletion processes exist. In particular, the speedy deletion process can result in deletion without discussion, and articles for deletion allows discussion to reach consensus for deletion. User:Linas (talk) 18:35, 2 December 2013 (UTC)
- I agree that it should be deleted, but it looks like you'll need to propose it again. Waleswatcher (talk) 16:08, 4 December 2013 (UTC)
- Of course, now it will have to be at AfD. RockMagnetist (talk) 16:27, 4 December 2013 (UTC)
A Wikipedia based textbook appears to be the primary textbook for a physics class
Per "Dr. Gavin Buffington, professor and chair of the Department of Physics at Fort Hays State University in Kansas. "I'm using a Boundless (company) textbook this semester in my Engineering Physics I class, and I've been impressed by the quality of content""[2] with this page [3] borrowing heavily from kinematics Congrats to all the Wikipedian authors here! Company states that they will improve attribution going forwards. Doc James (talk ·contribs · email) (if I write on your page reply on mine) 19:00, 6 December 2013 (UTC)
WikiProject Thermodynamics
FYI, there's a proposed wikiproject at Wikipedia:WikiProject Council/Proposals/Thermodynamics that you may be interested in voicing an opinion on. -- 65.94.78.9 (talk) 11:38, 7 December 2013 (UTC)
Notification: Featured Article Review for Stephen Hawking
There are some serious deficiencies which several users have identified in the Stephen Hawking article which was promoted to FA status earlier this year after an FAC that wasn't rigorous. Please feel free to comment and contribute to the debate at Wikipedia:Featured article review/Stephen Hawking/archive1 on whether this article should be delisted and what work needs to be done.--ColonelHenry (talk) 17:07, 7 December 2013 (UTC)
{{Infobox element}}
![](http://upload.wikimedia.org/wikipedia/commons/thumb/2/23/Nuvola_apps_edu_languages.svg/40px-Nuvola_apps_edu_languages.svg.png)
You can remove this notice at any time by removing the {{Talkback}} or {{Tb}} template.
FYI, there's a request to change {{elementbox}} at WPCHEMISTRY. See Wikipedia talk:WikiProject Chemistry#chembox for the discussion -- 65.94.78.9 (talk) 20:25, 7 December 2013 (UTC)
WP:CHEESE editor on neutron magnetic moments.
There's some IP (193.231.19.53 (talk · contribs)) ranting on and on about the "Rutherford model" (i.e. that the neutron is made of a proton + electron) on various nuclear magnetic moment-related pages (Talk:Neutron magnetic moment, Talk:Quark, Talk:Magnetic moment and a few others), claiming that the quark model isn't established and that the jury's still out there on the composition of neutrons. The remarks and arguments closely mirror those of the pseudoscience peddled by Ruggero Santilli (and in articles about the so-called "Rutherford-Santilly" model of the neutron) and collaborators, although the IP claims to never have heard of these people. Some help would be appreciated. Headbomb {talk / contribs / physics / books} 15:54, 10 December 2013 (UTC)
- Rutherford's article from 1920 concerning prediction of a neutron has been brought to my attention long before the recent mention of someone like Santilli by Headbomb. If someone like Santilli considers worth buiding upon Rutherford's hypothesis, that is an entirely different aspect.--193.231.19.53 (talk) 10:09, 17 December 2013 (UTC)
- There are a fair number of arguments that show that a neutron cannot be made of a proton+electron. Consider the following:
- Decay of a neutron yields a proton, electron, and an electron anti-neutrino. Now, maybe you could argue that the protron and electron are somehow "stuck together" in the neutron, but surely you agree that nothing can possibly confine the neutrino to the neutron? Remember, neutrinos are perfectly capable of penetrating light years of matter.
- Even the notion that a proton and electron could stick together is flakey, because of the Heisenberg uncertainty principle. It is quite simply inconceivable that an electron can be confined to the volume of a neutron.
- The electron is not subject to the strong force, so it can not be made to "stick" to the proton. Electromagnetic associations of protons and electrons are known as "hydrogen atoms".
- These arguments show that the electron and anti-neutrino could not have pre-existed as neutron constituents. The only explanation that makes sense is that the electron and the anti-neutrino were created during the decay event. Do you need more proof? I got more proof.
- Stigmatella aurantiaca (talk) 00:00, 18 December 2013 (UTC)
- As for arguments relating to the magnetic moment, see SSM Wong (1998), "Magnetic Dipole Moment of the Baryon Octet", Introductory Nuclear Physics, § 2.8, pp. 48ff, ISBN 978-0471239734 (or any other intro to nuclear physics textbook, really).Headbomb {talk / contribs / physics / books} 03:10, 18 December 2013 (UTC)
- There are a fair number of arguments that show that a neutron cannot be made of a proton+electron. Consider the following:
- My 1.5 cents, I think the best—read: the only—way to handle cheese amateurs is not to engage in any technical argument whatsoever. Technical arguments always bounce. That cheese astronomer is a lot dumber than the amateur. Just politely point to wp:V, wp:secondary sources and wp:BURDEN when you refer to what they are supposed to do in article space, and to wp:TPG and WP:NOTFORUM for article talk pages. When they keep at it, ignore the talk page chat and issue user talk page warnings {{uw-chat1}} up to {{uw-chat4}}. - DVdm (talk) 16:43, 10 December 2013 (UTC)
- At this point, I doubt that doing this myself would be productive. A third party is needed, as far as warning and so on goes. Headbomb {talk / contribs / physics / books} 16:55, 10 December 2013 (UTC)
- I have seen this discussion and I have to repeat what I have posted on neutron talk page: The discussion is not about wether or not neutron is made of quarks. A more cautious phrasing is needed and concerns the explanatory power of structure models formulated over the time since the prediction and discovery of the neutron.--188.26.22.131 (talk) 11:25, 16 December 2013 (UTC)
- Has anyone any objection to the above proposal of a more cautious wording?--193.231.19.53 (talk) 10:00, 17 December 2013 (UTC)
- I have seen this discussion and I have to repeat what I have posted on neutron talk page: The discussion is not about wether or not neutron is made of quarks. A more cautious phrasing is needed and concerns the explanatory power of structure models formulated over the time since the prediction and discovery of the neutron.--188.26.22.131 (talk) 11:25, 16 December 2013 (UTC)
- First party seems to somehow have got the message. - DVdm (talk) 11:09, 12 December 2013 (UTC)
- At this point, I doubt that doing this myself would be productive. A third party is needed, as far as warning and so on goes. Headbomb {talk / contribs / physics / books} 16:55, 10 December 2013 (UTC)
Somewhat related are related to Aabrucadubraa (talk · contribs), also a Santilli advocate. This time pushing for Magnecules and "IsoRedshift" (Santilli's take on the Hubble Law). Headbomb {talk / contribs / physics / books} 15:11, 14 December 2013 (UTC)
- Commented here. There's another somewhat similar case with LCcritic's length contraction criticisms. - DVdm (talk) 15:40, 14 December 2013 (UTC)
Promotion of World Scientific books
Two users Garuda0001 (talk · contribs) and Philipphilip0001 (talk · contribs) have been adding a bunch of books from World Scientific to our articles over the past year or so. On face values these seem like appropriate materials, but there have been highly-questionable additions (such as [4]), and since there clearly is a conflict of interest going on (all sources were from World Scientific) there is definitely something fishy here. I think I've reverted all of it, but feel free to go through the articles and make sure I purged it all (or reinstate whatever material you consider appropriate, provided you confirm its relevance / factual accuracy).
This really was a pain to clean up, given it's been in our articles for so long, and that single edits on their own do not look problematic. So keep an eye out for these two / similar users / WP:BEANS in the future.Headbomb {talk / contribs / physics / books} 10:33, 12 December 2013 (UTC)
File:Weak_Decay_(flipped).svg ... featured pic?
![](http://upload.wikimedia.org/wikipedia/commons/thumb/4/4b/Weak_Decay_%28flipped%29.svg/220px-Weak_Decay_%28flipped%29.svg.png)
I've been mulling over submitting this picture showing quark decays / CKM matrix coefficients for a featured picture. Does anyone here have any concern about it's accuracy / usefulness / anything? Note that we also have File:Quark weak interactions.svg which conveys similar information. Headbomb {talk / contribs / physics / books} 01:27, 14 December 2013 (UTC)
- I agree that the diagram is a well thought out and informative illustration of the CKM matrix. I think it is superior to File:Quark weak interactions.svg because it shows the mass scale and the direction of the transitions. I like the plot, but if you are looking for possible criticism... Someone trying to make sense of this would need to know what u, d, s, ... W represented. Stylistically, the Most/Least likely annotations are too small to easily read, at least at the thumbnail size. There is space at the top of the plot to make those annotations a bit larger without crowding the central digraph. --Mark viking (talk) 17:59, 14 December 2013 (UTC)
- I agree completely about the legend and the text size, Mark. I'll be happy to make that change. I'll also be happy to add a legend, if you don't think it would make it too "busy". My only concern there would be that we don't necessarily want to define everything on the graph (MeV, c, e, etc). Not exactly sure where (if anywhere) such a line should be drawn. As an aside, thank you Headbomb for making that colour adjustment for me. I realised that I misunderstood your request after you made that tweak. It was a pleasure working with you on the illustration. Niamh (talk) 00:51, 19 December 2013 (UTC)
- A good caption is all-important for submitting a scientific illustration such as this to Wikipedia:Featured picture candidates. Without a good caption, most of the regular denizens of that group would not know what to make of the illustration and would greet it with a stunned silence. Having successfully midwifed a couple of scientific illustration candidates through the Featured Picture process
and watched several favorites of mine emerge stillborn, I cannot overstress the need to make its importance evident to the layman. Stigmatella aurantiaca (talk) 02:21, 19 December 2013 (UTC)
- A good caption is all-important for submitting a scientific illustration such as this to Wikipedia:Featured picture candidates. Without a good caption, most of the regular denizens of that group would not know what to make of the illustration and would greet it with a stunned silence. Having successfully midwifed a couple of scientific illustration candidates through the Featured Picture process
- I agree completely about the legend and the text size, Mark. I'll be happy to make that change. I'll also be happy to add a legend, if you don't think it would make it too "busy". My only concern there would be that we don't necessarily want to define everything on the graph (MeV, c, e, etc). Not exactly sure where (if anywhere) such a line should be drawn. As an aside, thank you Headbomb for making that colour adjustment for me. I realised that I misunderstood your request after you made that tweak. It was a pleasure working with you on the illustration. Niamh (talk) 00:51, 19 December 2013 (UTC)
Consciousness causes collapse
Please note the Consciousness causes collapse article is up for deletion under the name Wikipedia:Articles for deletion/Quantum mind–body problem.—Machine Elf 1735 07:06, 17 December 2013 (UTC)
Addressing articles' comprehensibility problems
Some articles have comprehensibility problems. For a non-expert it's difficult - sometimes impossible - to tell which is the current status of the research/concept or to which theory does the concept belong. To clarify what I mean, I will give two examples.
- Supersymmetry is a long article. Huge. It is however not obvious how does SUSY apply to SM, to string theory and more important what was the motivation for introducing the concept. Some references in current status are as old as 2009 and by no means can someone properly understand how the theory is impacted by the results (negative that is) from CERN or LUX. There is a good strong motivation for introducing this extension and at the same time SUSY's feathers are ruffled; both things should stand out on the page.
- Tachyons are related to SUSY and yet there is no indication in the article. Moreover, the references point them out to be synonym with inconsistency in the theory, without stating which theory (I found it to be - for example - bosonic string d=26 and not - for example - relativity, how someone less informed may be inclined to believe). And no, it's not obvious nor self-explanatory. One can say that tachyons are not an important concept, but I will argue that an ill-understood idea tends to become important.
The point here is Wikipedia is supposed to be useful for the keeping the general public informed, not confused. And the effort for fixing this cannot be taken by a single editor (I, for one, am in). Who else would be interested in such a task? Can you think of ways to improve this situation? What we can do would be to methodically revise the introductions of these articles and add tags like 'belongs to standard model and string theory'. Also state why is the concept important, what problem does it fix, with which theory does it conflict and how, as these are the most important barebone characteristics. Such an introduction would provide coordinates to map the concept over the existing knowledge. I also think it may be suitable to make the 'current status' more visible by - for example - moving it to the beginning of the article. Looking for your thoughts. (I address this here because the quality control talk page is last dated Jan 2013 and no-on ever replied to that statement) (talk) Alma 20:37, 20 December 2013 (UTC)
- I think that Alma's concerns are justified. The disorganization and confusion results results from the writing of many different editors, often with bees in their bonnets who may reluctant to accept changes to their work. I wish him the best in his attempts to improve the situation. Xxanthippe (talk) 05:13, 21 December 2013 (UTC).
Excimer lamp
Can somebody clear this sentence up and add it to the article? An excimer lamp (or excilamp) is a source of ultraviolet light producing by spontaneous emission of excimer (exciplex) molecules. Robert (talk) 23:13, 21 December 2013 (UTC)
The article on Bell's Theorem has been an enormous mess for a long time. I just started doing some cleaning up but a major rewrite is needed. Maybe it is a good time to do this? The usual controversies are somewhat abated at the moment. It needs a concerted effort by a lot of reasonably well-informed people, who are not in the first place motivated by a particular (minority?) point of view on the topic. Richard Gill (talk) 11:39, 22 December 2013 (UTC)
- What flaw(s) do you see as requiring a complete rewrite of the article? --Mark viking (talk) 23:43, 22 December 2013 (UTC)
- Hi Richard, I noticed that ref #2 returns a missing page. Since you are already on the subject, here is a new link that works http://www.its.caltech.edu/~qoptics/ph135b/Bell-inequalities_v2_r.pdf . Hope this helps! Alma (talk) 10:15, 23 December 2013 (UTC) Actually maybe I can revise the references and point them to online sources (as many of them are offline sources right now) so you won't waste time with that. What do you think? Alma (talk) 10:24, 23 December 2013 (UTC)
FYI, Aeronautics (edit | talk | history | protect | delete | links | watch | logs | views) has been proposed to be merged into aviation, see talk:aviation -- 65.94.78.9 (talk) 23:24, 23 December 2013 (UTC)