Have a deep view into what people are curious about.

🔗 Mathematics

The 15-puzzle (also called Gem Puzzle, Boss Puzzle, Game of Fifteen, Mystic Square and many others) is a sliding puzzle that consists of a frame of numbered square tiles in random order with one tile missing. The puzzle also exists in other sizes, particularly the smaller 8-puzzle. If the size is 3×3 tiles, the puzzle is called the 8-puzzle or 9-puzzle, and if 4×4 tiles, the puzzle is called the 15-puzzle or 16-puzzle named, respectively, for the number of tiles and the number of spaces. The object of the puzzle is to place the tiles in order by making sliding moves that use the empty space.

The n-puzzle is a classical problem for modelling algorithms involving heuristics. Commonly used heuristics for this problem include counting the number of misplaced tiles and finding the sum of the taxicab distances between each block and its position in the goal configuration. Note that both are admissible, i.e. they never overestimate the number of moves left, which ensures optimality for certain search algorithms such as A*.

🔗 Disaster management 🔗 Medicine 🔗 China 🔗 Food and drink 🔗 Medicine/Toxicology 🔗 Taiwan

Gutter oil (Chinese: 地沟油; pinyin: dìgōu yóu, or 餿水油; sōushuǐ yóu) is oil which has been recycled from waste oil collected from sources such as restaurant fryers, grease traps, slaughterhouse waste and fatbergs.

Reprocessing of used cooking oil is often very rudimentary; techniques include filtration, boiling, refining, and the removal of some adulterants. It is then packaged and resold as a cheaper alternative to normal cooking oil. Another version of gutter oil uses discarded animal parts, animal fat and skins, internal organs, and expired or otherwise low-quality meat, which is then cooked in large vats in order to extract the oil. Used kitchen oil can be purchased for between $859 and $937 per ton, while the cleaned and refined product can sell for $1,560 per ton. Thus there is great economic incentive to produce and sell gutter oil.

It was estimated in 2011 that up to one in every ten lower-market restaurant meals consumed in China is prepared with recycled oil. As Feng Ping of the China Meat Research Center has said: "The illegal oil shows no difference in appearance and indicators after refining and purification because the law breakers are skillful at coping with the established standards."

Some street vendors and restaurants in China and Taiwan have illegally used recycled oil unfit for human consumption for the purposes of cooking food, leading to a crackdown against such establishments by the Chinese and Taiwanese governments.

Gutter oil is an acceptable raw ingredient for products that are not for human consumption, such as soap, rubber, bio-fuel, and cosmetics.

🔗 Plants 🔗 Psychoactive and Recreational Drugs 🔗 Altered States of Consciousness 🔗 South America

Ayahuasca is a South American (pan-Amazonian) psychoactive brew used both socially and as ceremonial spiritual medicine among the indigenous peoples of the Amazon basin. It is a psychedelic and entheogenic brew commonly made out of the Banisteriopsis caapi vine, the Psychotria viridis shrub or a substitute, and possibly other ingredients. A chemically similar preparation, sometimes called "pharmahuasca", can be prepared using N,N-Dimethyltryptamine (DMT) and a pharmaceutical monoamine oxidase inhibitor (MAOI), such as isocarboxazid. B. caapi contains several alkaloids that act as MAOIs, which are required for DMT to be orally active. Ayahuasca is prepared in a tea that, when consumed, causes an altered state of consciousness or "high", including visual hallucinations and altered perceptions of reality.

The other required ingredient is a plant that contains the primary psychoactive, DMT. This is usually the shrub P. viridis, but Diplopterys cabrerana may be used as a substitute. Other plant ingredients often or occasionally used in the production of ayahuasca include Justicia pectoralis, one of the Brugmansia (especially Brugmansia insignis and Brugmansia versicolor, or a hybrid breed) or Datura species, and mapacho (Nicotiana rustica).

🔗 Books 🔗 The KLF

The Manual (How to Have a Number One the Easy Way) is a 1988 book by "The Timelords" (Jimmy Cauty and Bill Drummond), better known as The KLF. It is a step-by-step guide to achieving a No.1 single with no money or musical skills, and a case study of the duo's UK novelty pop No. 1 "Doctorin' the Tardis".

🔗 Physics 🔗 Astronomy 🔗 Chemistry 🔗 Water 🔗 Astronomy/Solar System

Superionic water, also called superionic ice or ice XVIII, is a phase of water that exists at extremely high temperatures and pressures. In superionic water, water molecules break apart and the oxygen ions crystallize into an evenly spaced lattice while the hydrogen ions float around freely within the oxygen lattice. The freely mobile hydrogen ions make superionic water almost as conductive as typical metals, making it a superionic conductor. It is one of the 19 known crystalline phases of ice. Superionic water is distinct from ionic water, which is a hypothetical liquid state characterized by a disordered soup of hydrogen and oxygen ions.

While theorized for decades, it was not until the 1990s that the first experimental evidence emerged for superionic water. Initial evidence came from optical measurements of laser-heated water in a diamond anvil cell, and from optical measurements of water shocked by extremely powerful lasers. The first definitive evidence for the crystal structure of the oxygen lattice in superionic water came from x-ray measurements on laser-shocked water which were reported in 2019.

If it were present on the surface of the Earth, superionic ice would rapidly decompress. In May 2019, scientists at the Lawrence Livermore National Laboratory (LLNL) were able to synthesize superionic ice, confirming it to be almost four times as dense as normal ice and black in color.

Superionic water is theorized to be present in the mantles of giant planets such as Uranus and Neptune.

🔗 Biography 🔗 Africa 🔗 Japan 🔗 Japan/History 🔗 Japan/Biography

Yasuke (variously rendered as 弥助 or 弥介, 彌助 or 彌介 in different sources) was a man of African origin who served as a retainer under the Japanese daimyō Oda Nobunaga. In 1579, Yasuke arrived in Japan in the service of Italian Jesuit missionary Alessandro Valignano, Visitor of Missions in the Indies, in India.

Yasuke is thought by some to have been the first African that Nobunaga had ever seen and he was one of the many Africans to have come with the Portuguese to Japan during the Nanban trade. He was also present during the Honnō-ji Incident, the forced suicide of Nobunaga at the hands of his samurai general Akechi Mitsuhide on 21 June 1582.

🔗 Computer Security 🔗 Computer Security/Computing

Zombie Zero is an attack vector where a cyber attacker utilized malware that was clandestinely embedded in new barcode readers which were manufactured overseas.

It remains unknown if this attack was promulgated by organized crime or a nation state. Clearly there was significant planning and investment in order to design the malware, and then embed it into the hardware within the barcode scanner. Internet of things (IoT) devices may be similarly preinstalled with malware that can capture the network passwords and then open a backdoor to attackers. Given the high volume of these devices manufactured overseas high caution is to be exercised before placing these devices on corporate or government networks.

🔗 Central Asia 🔗 Mining 🔗 Central Asia/Turkmenistan 🔗 Turkmenistan

The Darvaza gas crater (Turkmen: Garagum ýalkymy), also known as the Door to Hell or Gates of Hell, or, officially, the Shining of Karakum, is a burning natural gas field collapsed into a cavern near Darvaza, Turkmenistan. The floor and especially rim of the crater is illumined by hundreds of natural gas fires. The crater has been burning for an unknown amount of time, as how the crater formed and ignited remains unknown.

🔗 Electronics 🔗 Electrical engineering

The trancitor as the combined word of a "transfer-capacitor" is to be considered as another active-device category besides the transistor as a "transfer-resistor". As observed in the table shown, four kinds of active devices are theoretically deduced. Among them, trancitors are missing to be the third and fourth kinds, whereas transistors, such as bipolar junction transistor (BJT) and field-effect transistor (FET), were already invented as the first and second kinds, respectively. Unlike the transistor switching the current at its output (i.e., current source), the trancitor transfers its input to the voltage output (i.e., voltage source), so an inverse relationship with each other.

🔗 Department of Fun

An article about or described by any of the following can be safely assumed to fit into the set of unnecessary articles:

1. You, your family, or the organization you work for.
2. Your band, which has only sold 47 copies of its one album. Even if you think it will sell 48. Or maybe 49! Or, if you get really lucky, you can pay off the record store owner so that he may buy one and your sales will have gone up to fifty!!! Keep dreamin', brotha.
3. Your imaginary friend or your imaginary friends that don't even exist.
4. The religion, language or even country that you made up with your friends in school one day.
5. The street you live on, unless it is on a Monopoly board. But since it is highly unlikely that you live on a Monopoly game board, we suggest that you not even try.
6. Any one of the 16 distinct regions in the Pokémon video game series or lieking mudkipz, or hering dat someon lieks mudkipz. Remember, not everyone is a Pokémon fanatic.
7. A stunt or trick only you have ever attempted, probably unsuccessfully.
8. Any movie you made yourself which has never been seen by more people at one time than can fit in your basement. Even if you have a really big basement.
9. Individual songs that have never been released as a single nor seen radio play, unless they're twenty minutes long or have led to a phone number becoming unusable or even have questioned the essence of music itself.
10. "(Anything) in popular culture." Anything at all.
11. Likewise "Hysterical Realism in the Works of (insert neither hysterical nor realistic author here)".
12. Your dormitory, university residence, or any suite therein.
13. Stuff nobody but that guy who changes his Spock ears more often than his underpants cares about, or the equivalent thereto. For example, a song about a custom map of a video game, unless you are famous and the song managed to release as a single.
14. Anything about which you cannot be buggered to write one complete sent
15. Subjects that cannot be studied, or the knowledge of which amounts only to the fact that it pertains to another topic. A favourite line from a movie or catchy lyric, a potent phrase used in argument, juicy facts of interest to fans, a punch-line or zinger; these are all very interesting, but usually all that can be informatively written about topic "X" is: "X is a _______ found in _______."
16. Just about everything listed on Wikipedia:Millionth topic pool.
17. For that matter, Wikipedia:Millionth topic pool.
18. Anything about your cat or dog and how cute it is (or your hamster, degu, or chinchilla).
19. Exploding Whales, or indeed Exploding Wales, or even Exploding Wales. Or blowing up any other animals, for example, exploding mice, or even exploding Velociraptor, for that matter. Most things that implode are pretty much off the list too, with a few exceptions.
20. Anything written under the influence of recreational substances or while tired and emotional.
21. An article about another article, written after the use of aforementioned substances.
22. A fork of an existing article for the sole purpose of adding some humor.
23. The weather in London. Not even a redirect. (Wowee).
24. Your guild in World of Warcraft or similar time wasters. Just because you have no life a personally fascinating hobby doesn't mean you get to tell the world about it. And don't write about this guy in your guild who wiped your raid, either.
25. Something you just saw on YouTube and, possibly, laughed at.
26. Something you just put on YouTube.
27. An article that haz badly grammar and/or speelling. Including, bad punctuation!!
28. Any meme, no matter how popular or important.
29. Anything you don't know the title of.
30. Your wiki or blog. It's probably not internationally famous. If it is, well go ahead, but let's face it; your blog of cute cats is not internationally famous (three readers is not fame).
31. Your new invention or research paper that will change the world. It will undoubtedly fail.
32. Anything about your cat named Bubba or your dog named Max. No one cares. Trust us.
33. Your nomination for the Noble (or even Nobel) Peace Prize.
34. Anything about how you were abducted by aliens.
35. An article on the dream you had last night. No matter how long you describe it, it will never be interesting: Even if dreaming that you were the inventor of the chalk board who had to overcome obstacles from the evil book binding lobbyists deeply moved you to tears upon waking up.
36. An article on the person that knocked on your door while you was writing the article about your dream last night, causing you to forget about the dream (but I’ll be honest, I feel for you).
37. An article about Wikpiedia, Wikipaedia, Wiokipedia, Wikipeedia, Wikipeadia, or any other Wikis that appear to be Wikipedia but aren't.
38. An article about the media response to the Wikipedia article about the barely notable thing that shouldn't even have an article (recursivity has its limits, even here).
39. The difference between Hoagy Carmichael and Stokely Carmichael.
40. An entry promoting your hilarious web series about Wikipedia.
41. Recreating this dumb list.
42. Anything about hashtags. #IHateHashtags
43. Anything about how fat you are or how much weight you're losing (trust us; no one cares).
44. Headlight flashing – I know, it's preposterous, even for Wikipedia. But when you're done laughing and/or crying, follow the link. It really exists.
45. Assumptions about the conclusions of scientific publications that you have seen the titles of, but not read.
46. Your self-published book.
47. McGannahan Skjellyfetti.
48. An article about your friend's latest selfie. Or, for that matter, selfie stick. They are banned in most places anyway.
49. Lists of times at which commercial breaks occurred during a sporting event.
50. Your personal opinions about your boyfriend or girlfriend.
51. An article on discussing the differences between you and your close friends. It does not matter to most people in the world.
52. An article about how Tyson Foods is run by a bunch of chicken fuckers because the main article is protected from vandalism by the legions of Internet trolls.
53. Yet another list of Google doodles.
54. A new sex position that you and your boys theory-crafted one night.
55. Times Scooby-Doo has defied the laws of reality.
56. A list of celebrity couples names for couples that you wish would get together but as of now haven't.
57. Your stupid esoteric programming language you made up to 'test the boundaries of computer programming language design'.
58. Any article related to odorous gas clouds, but particularly smelly farts.
59. Your youtube channel, unless you have millions of fangirls.
60. Your opinion and/or fascination about outer space, even if there are lots of unusual exoplanets out there. Yes, we know. They're weird. No need to tell us that.
61. Your opinion on time traveling to have dinner with the members of Bone Symphony or Bone Thugs-n-Harmony or Boney M. or The Right Honourable Bonar Law
62. The time you laughed about someone eating a red 5-pound gummy skull while wearing a jetpack while driving a limousine at 5 a.m. on a Tuesday in August 2018.
63. An article that uses templates to perform math for no apparent reason besides your entertainment
64. Your anus and how it had very good funny time with girl.
65. The time you laughed at someone living in Fortnite (Chapter 1), even though I get that they were eaten by a Black hole. Oh well, they came back!
66. Posting a video of yourself saying the n-word.
67. Posting an image of yourself falling off the Burj Khalifa.
68. Singing any Cardi B song.
69. Posting 69 (nice) useless messages made by bored editors of Wikipedia.
70. Your low-effort school play of "How the Grinch Stole Christmas!"
71. A list of times you pinged @everyone on your Discord server.