Wikipedia:Reference desk/Archives/Miscellaneous/2017 September 10

= September 10 =

Chess central checkmate 2 Queens hypothetical
If White has 2 Queen's and King vs Black King is it possible to get a checkmate with the Black King on one of the central squares (E4, E5, D4 or D5)? (Mobile mundo (talk) 00:07, 10 September 2017 (UTC))


 * Yes, for example black's king at D4, white's king at D6, one queen in the 3rd row and one in the 4th row is one mate position. It's pretty straightforward for white to force this position.--Wikimedes (talk) 01:02, 10 September 2017 (UTC)
 * However Black can forestall the checkmate by . Blooteuth (talk) 12:35, 10 September 2017 (UTC)
 * When I played tournament chess and was in a losing position I would resign before I was checkmated.  Most players would do the same.   Unfortunately, on one occasion when I was offered a draw I didn't accept and went on to lose, which lost me a cup as it was awarded on a player's percentage over the season. 2A00:23C1:3180:B601:FC37:C608:7C91:52D6 (talk) 12:52, 10 September 2017 (UTC)

Pictures of film posters
I understand that most posters of films released in the past few decades are copyrighted. What I am curious about however is this: if I took a picture of a film's poster, DVD cover, etc. could I release the picture that I personally took, in the public domain? PanagiotisZois (talk) 14:40, 10 September 2017 (UTC)
 * No, “if you take a picture, you are making a reproduction and that is a copyright violation,” Prof. Sprigman said. NYT. C0617470r (talk) 17:51, 10 September 2017 (UTC)
 * Son of a bitch. Oh well, irregardless, thank you for the clarification. :) PanagiotisZois (talk) 22:49, 10 September 2017 (UTC)
 * You can photograph whatever you like, for personal use, at least in the USA, and if it's out in public view. Not necessarily so, inside a museum, or in other countries. And unless a country honors "freedom of panorama", you can't post it here. ←Baseball Bugs What's up, Doc? carrots→ 01:55, 11 September 2017 (UTC)
 * (Courtesy link added by 2606:A000:4C0C:E200:E47B:CDC9:8A2E:CA14 (talk) 02:28, 11 September 2017 (UTC))
 * Just so that I can make my case specifically clear: I'm talking about the cover of a German DVD that I bought in Germany, and from what I saw, Germany does have freedom of panorama. Taking all those things into consideration. Could I publish the picture in the public domain / upload it here? — Preceding unsigned comment added by PanagiotisZois (talk • contribs)
 * No, freedom of panorama only covers architectural and three-dimensional art works (sculptures etc.). Flat works of art are not usually covered.  -- Jayron 32 12:34, 11 September 2017 (UTC)
 * Fair use is a doctrine originating in the law of the United States that permits limited use of copyrighted material without having to first acquire permission from the copyright holder. English Wikipedia includes non-free image files such as film posters under fair use doctrine, for which editors should follow this rationale guideline. A typical case is Wikipedia's rationale for use of the "Titanic" poster art that mentions reduced image resolution, use in critical commentary of the film, and unavailability of an adequate free content replacement. Furthermore (but not a general legal advice), a US court has concluded that the publicity materials for The Wizard of Oz and Gone with the Wind, as well as for the Tom & Jerry short films, are in the public domain. Blooteuth (talk) 14:24, 11 September 2017 (UTC)
 * Just to spell it out so that it's obvious, the USA's copyright laws changed in the 70s. The legal arguments from the Wizard of Oz case wouldn't work on posters created after the mid 70s. ApLundell (talk) 14:31, 11 September 2017 (UTC)
 * Actually Commons:Commons:Freedom of panorama claims Germany does have FOP for 2D art works. But it requires a permanent installation and public display, one or both of which are probably not going to apply to a film poster or DVD cover. Note in the case of the Wikimedia Commons, while FOP content where the work is probably not covered under US FOP law is currently allowed, it's not guaranteed this will continue, see Commons:Template:Not-free-US-FOP and Commons:Commons:Freedom of panorama. We can't give legal advice here, if you want non legal advice specifically relating to uploading content to the wikimedia commons, it's probably best to seek help there since that's where you're likely to find people used to what normally happens on commons. Nil Einne (talk) 16:58, 12 September 2017 (UTC)

Black holes
What threat does the earth face from black holes? Could there be some lurking out there that could quite rapidly appear? Maybe small-ish ones, perhaps the size of the moon that we can't / havent detected? — Preceding unsigned comment added by 80.195.5.225 (talk) 22:33, 10 September 2017 (UTC)
 * The article Primordial black hole includes some information indirectly relevant to your questions. Be careful when you discuss "size": do you mean physical dimensions or mass? a black hole the mass of our Moon would, for example, have a 'diameter' of around one tenth of a millimeter (per our Black hole article): black holes smaller than this should evaporate via Hawking radiation rather than grow larger by accretion of mass. {The poster formerly known as 87.81.230.195} 2.122.61.201 (talk) 02:52, 11 September 2017 (UTC)


 * None. None whatsoever. In terms of dangers to the Earth from astronomical bodies, everything is a point mass, and there's nothing remotely special about black holes versus any other wandering mass we might stumble across. A stellar-mass black hole transiting the solar system will probably kill us all by disrupting planetary orbits, because any stellar mass transiting the solar system will probably kill us all by disrupting planetary orbits. A stellar-mass black hole five light years away will have zero effect on the Earth, because stellar masses five light years away have zero effect on the Earth. Switch things to a black hole with an active accretion disk throwing hard radiation around and the answer might be different &mdash; but we know where those are because they're radiating loudly; they're not (figuratively) "black". &mdash; Lomn 19:22, 11 September 2017 (UTC)
 * To be pedantic, I think there's speculation that nearby star systems can perturb things in the Oort cloud, sometimes sending them careening into the inner Solar System, but yes, the general point is correct. Black holes aren't magic. They're just very dense objects. The standard thought experiment is to suppose the Sun were replaced with a black hole of equivalent mass. Earth would merrily continue orbiting the black hole just as it orbits the Sun now, since it's way outside where the black hole's event horizon would be. It would just be really cold and dark. For more, here's Crash Course Astronomy's episode on black holes. --47.138.161.183 (talk) 07:35, 12 September 2017 (UTC)


 * More answers to this question. —Tamfang (talk) 06:40, 15 September 2017 (UTC)

Island cemeteries


The cemeteries at several Chesapeake Bay island communities all have some unusual features — casket-sized rectangular features covering much or most of the cemetery. See the following locations: What are they? Structural supports to enable placement of further caskets on top, given the islands' limited room for burials? Caps to prevent the casket opening or floating off in a flood? I've seen big flat structures in a mainland cemetery (see the background of File:Vardeman-Holmes-Stephenson Cemetery.jpg in Kentucky, for example), but only a few times at most, they're merely flat slabs in place of a vertical headstone (not behind it, as here), and they never dominate the cemetery as in any of these island cemeteries. The Tangier article only mentions the cemeteries in passing, remarking on cemetery overcrowding, and the other three articles don't mention cemeteries at all. Nyttend (talk) 23:48, 10 September 2017 (UTC)
 * 37.82694°N, -75.99222°W at Tangier (pictured)
 * 37.96778°N, -76.02333°W at Tylerton
 * 37.995°N, -76.03333°W at Ewell
 * 37.97528°N, -76.04167°W at Rhodes Point
 * These are burial vaults; in places with a high water table or with dangers of flooding, they may, by design, not fully be underground. -- Jayron 32 11:34, 11 September 2017 (UTC)
 * The highest elevation on Tangiers is 6ft above sea level so putting someone "6 feet under" will pose some difficulties. Rmhermen (talk) 11:47, 11 September 2017 (UTC)


 * And here are some of those "difficulties" elsewhere: Coffins and Buried Remains Set Adrift by Hurricanes Create a Grisly Puzzle. "A coffin showed up on the lawn of Dr. Bryan Bertucci, the coroner of St. Bernard Parish. And later, a parish resident informed Dr. Bertucci that he found the remains of his grandmother, still wearing her pink gown, out of her grave in a local cemetery". Alansplodge (talk) 12:53, 11 September 2017 (UTC)