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Thursday, December 6, 2018

Flatland

From Wikipedia, the free encyclopedia

Flatland: A Romance of Many Dimensions
Houghton EC85 Ab264 884f - Flatland, cover.jpg
The cover to Flatland, first edition
AuthorEdwin A. Abbott
IllustratorEdwin A. Abbott
CountryUnited Kingdom
GenreMathematical fiction
PublisherSeeley & Co.
Publication date
1884
OCLC2306280
LC ClassQA699
TextFlatland: A Romance of Many Dimensions at Wikisource

Flatland: A Romance of Many Dimensions is a satirical novella by the English schoolmaster Edwin Abbott Abbott, first published in 1884 by Seeley & Co. of London.

Written pseudonymously by "A Square", the book used the fictional two-dimensional world of Flatland to comment on the hierarchy of Victorian culture, but the novella's more enduring contribution is its examination of dimensions.

Several films have been made from the story, including the feature film Flatland (2007). Other efforts have been short or experimental films, including one narrated by Dudley Moore and the short films Flatland: The Movie (2007) and Flatland 2: Sphereland (2012).

Plot

Illustration of a simple house in Flatland.

The story describes a two-dimensional world occupied by geometric figures, whereof women are simple line-segments, while men are polygons with various numbers of sides. The narrator is a square named A Square, a member of the caste of gentlemen and professionals, who guides the readers through some of the implications of life in two dimensions. The first half of the story goes through the practicalities of existing in a two-dimensional universe as well as a history leading up to the year 1999 on the eve of the 3rd Millennium.

On New Year's Eve, the Square dreams about a visit to a one-dimensional world (Lineland) inhabited by "lustrous points". These points are unable to see the Square as anything other than a set of points on a line. Thus, the Square attempts to convince the realm's monarch of a second dimension; but is unable to do so. In the end, the monarch of Lineland tries to kill A Square rather than tolerate his nonsense any further.

Following this vision, he is himself visited by a three-dimensional sphere named A Sphere. Similar to the "points" in Lineland, the Square is unable to see the sphere as anything other than a circle. The Sphere then levitates up and down through the Flatland, allowing Square to see the circle expand and retract. The Square is not fully convinced until he sees Spaceland (a tridimensional world) for himself. This Sphere visits Flatland at the turn of each millennium to introduce a new apostle to the idea of a third dimension in the hopes of eventually educating the population of Flatland. From the safety of Spaceland, they are able to observe the leaders of Flatland secretly acknowledging the existence of the sphere and prescribing the silencing of anyone found preaching the truth of Spaceland and the third dimension. After this proclamation is made, many witnesses are massacred or imprisoned (according to caste), including A Square's brother, B.

After the Square's mind is opened to new dimensions, he tries to convince the Sphere of the theoretical possibility of the existence of a fourth (and fifth, and sixth ...) spatial dimension; but the Sphere returns his student to Flatland in disgrace.

The Square then has a dream in which the Sphere visits him again, this time to introduce him to Pointland, whereof the point (sole inhabitant, monarch, and universe in one) perceives any communication as a thought originating in his own mind (cf. Solipsism):
"You see," said my Teacher, "how little your words have done. So far as the Monarch understands them at all, he accepts them as his own – for he cannot conceive of any other except himself – and plumes himself upon the variety of Its Thought as an instance of creative Power. Let us leave this god of Pointland to the ignorant fruition of his omnipresence and omniscience: nothing that you or I can do can rescue him from his self-satisfaction."
— the Sphere
 
The last sketch in the book.

The Square recognises the identity of the ignorance of the monarchs of Pointland and Lineland with his own (and the Sphere's) previous ignorance of the existence of higher dimensions. Once returned to Flatland, the Square cannot convince anyone of Spaceland's existence, especially after official decrees are announced that anyone preaching the existence of three dimensions will be imprisoned (or executed, depending on caste). Eventually the Square himself is imprisoned for just this reason, with only occasional contact with his brother who is imprisoned in the same facility. He does not manage to convince his brother, even after all they have both seen. Seven years after being imprisoned, A Square writes out the book Flatland in the form of a memoir, hoping to keep it as posterity for a future generation that can see beyond their two-dimensional existence.

Social elements

Men are portrayed as polygons whose social status is determined by their regularity and the number of their sides, with a Circle considered the "perfect" shape. On the other hand, women consist only of lines and are required by law to sound a "peace-cry" as they walk, lest they be mistaken face-to-face for a point. The Square evinces accounts of cases where women have accidentally or deliberately stabbed men to death, as evidence of the need for separate doors for women and men in buildings.

In the world of Flatland, classes are distinguished by the "Art of Hearing", the "Art of Feeling", and the "Art of Sight Recognition". Classes can be distinguished by the sound of one's voice, but the lower classes have more developed vocal organs, enabling them to feign the voice of a Polygon or even a Circle. Feeling, practised by the lower classes and women, determines the configuration of a person by feeling one of its angles. The "Art of Sight Recognition", practised by the upper classes, is aided by "Fog", which allows an observer to determine the depth of an object. With this, polygons with sharp angles relative to the observer will fade more rapidly than polygons with more gradual angles. Colour of any kind is banned in Flatland after Isosceles workers painted themselves to impersonate noble Polygons. The Square describes these events, and the ensuing class war at length.

The population of Flatland can "evolve" through the "Law of Nature", which states: "a male child shall have one more side than his father, so that each generation shall rise (as a rule) one step in the scale of development and nobility. Thus the son of a Square is a Pentagon, the son of a Pentagon, a Hexagon; and so on".

This rule is not the case when dealing with isosceles triangles (Soldiers and Workmen) with only two congruent sides. The smallest angle of an Isosceles Triangle gains thirty arc minutes (half a degree) each generation. Additionally, the rule does not seem to apply to many-sided Polygons. For example, the sons of several hundred-sided Polygons will often develop fifty or more sides more than their parents. Furthermore, the angle of an Isosceles Triangle or the number of sides of a (regular) Polygon may be altered during life by deeds or surgical adjustments.

An equilateral triangle is a member of the craftsman class. Squares and Pentagons are the "gentlemen" class, as doctors, lawyers, and other professions. Hexagons are the lowest rank of nobility, all the way up to (near) Circles, who make up the priest class. The higher-order Polygons have much less of a chance of producing sons, preventing Flatland from being overcrowded with noblemen.

Only regular Polygons are considered until chapter seven of the book when the issue of irregularity, or physical deformity, became considered. In a two dimensional world a regular polygon can be identified by a single angle and/or vertex. To maintain social cohesion, irregularity is to be abhorred, with moral irregularity and criminality cited, "by some" (in the book), as inevitable additional deformities, a sentiment with which the Square concurs. If the error of deviation is above a stated amount, the irregular Polygon faces euthanasia; if below, he becomes the lowest rank of civil servant. An irregular Polygon is not destroyed at birth, but allowed to develop to see if the irregularity can be "cured" or reduced. If the deformity remains, the irregular is "painlessly and mercifully consumed."

As a social satire

In Flatland Abbott describes a society rigidly divided into classes. Social ascent is the main aspiration of its inhabitants, apparently granted to everyone but strictly controlled by the top of the hierarchy. Freedom is despised and the laws are cruel. Innovators are imprisoned or suppressed. Members of lower classes who are intellectually valuable, and potential leaders of riots, are either killed, or promoted to the higher classes. Every attempt for change is considered dangerous and harmful. This world is not prepared to receive "Revelations from another world".

The satirical part is mainly concentrated in the first part of the book, "This World", which describes Flatland. The main points of interest are the Victorian concept of women's roles in the society and in the class-based hierarchy of men. Abbott has been accused of misogyny due to his portrait of women in Flatland. In his Preface to the Second and Revised Edition, 1884, he answers such critics by emphasizing that the description of women was satirizing the viewpoints held, stating that the Square:
was writing as a Historian, he has identified himself (perhaps too closely) with the views generally adopted by Flatland and (as he has been informed) even by Spaceland, Historians; in whose pages (until very recent times) the destinies of Women and of the masses of mankind have seldom been deemed worthy of mention and never of careful consideration.
— the Editor

Critical reception

Although Flatland was not ignored when it was published, it did not obtain a great success. In the entry on Edwin Abbott in the Dictionary of National Biography, Flatland is not even mentioned.

The book was discovered again after Albert Einstein's general theory of relativity was published, which brought to prominence the concept of a fourth dimension. Flatland was mentioned in a letter entitled "Euclid, Newton and Einstein" published in Nature on 12 February 1920. In this letter Abbott is depicted, in a sense, as a prophet due to his intuition of the importance of time to explain certain phenomena:
Some thirty or more years ago a little jeu d'esprit was written by Dr. Edwin Abbott entitled Flatland. At the time of its publication it did not attract as much attention as it deserved... If there is motion of our three-dimensional space relative to the fourth dimension, all the changes we experience and assign to the flow of time will be due simply to this movement, the whole of the future as well as the past always existing in the fourth dimension.
— from a "Letter to the Editor" by William Garnett. in Nature on February 12, 1920.
The Oxford Dictionary of National Biography now contains a reference to Flatland.

Adaptations and parodies

Numerous imitations or sequels to Flatland have been created. Examples include:

In film

In literature

Books and short stories inspired by Flatland include:

Popular culture

Physicists and science popularizers Carl Sagan and Stephen Hawking have both commented on and postulated about the effects of Flatland. Sagan recreates the thought experiment as a set-up to discussing the possibilities of higher dimensions of the physical universe in both the book and television series Cosmos, whereas Hawking notes the impossibility of life in two-dimensional space, as any inhabitants would necessarily be unable to digest their own food.

Flatland features in The Big Bang Theory episode "The Psychic Vortex", when Sheldon Cooper declares it one of his favourite imaginary places to visit.

It also features in the Futurama episode "2-D Blacktop", when Professor Farnsworth's adventures in drag racing lead to a foray of drifting in and out of inter-dimensional spaces.

The main antagonist of Gravity Falls, Bill Cipher, is hinted to hail from a world like Flatland, describing the inhabitants of his dimension as "flat minds in a flat world with flat dreams" and responding to inquiries about his origins on Reddit that "EDWIN ABBOTT ABBOTT HAS A DECENT IDEA."

On the series The Orville, episode "New Dimensions", Captain Ed Mercer references Flatland and its theme of social hierarchy in response to both the discovery of a two-dimensional anomaly in space, as well as his and another colleague's questionable promotions through the ranks.

In the episode of the series The Problem Solverz "Zoo Cops", Flatland is described by Dorkface as A 2-Dimensional world where everyone is flat like a sticker. The world is also home to TuxDog's 2D Doppelgänger FlatDog.

Materials science in science fiction

From Wikipedia, the free encyclopedia
 
Materials science in science fiction is the study of how materials science is portrayed in works of science fiction. The accuracy of the materials science portrayed spans a wide range – sometimes it is an extrapolation of existing technology, sometimes it is a physically realistic portrayal of a far-out technology, and sometimes it is simply a plot device that looks scientific, but has no basis in science. Examples are:
  • Realistic case: In 1944, the science fiction story "Deadline" by Cleve Cartmill depicted the atomic bomb. The properties of various radioactive isotopes are critical to the proposed device, and the plot. This technology was real, unknown to the author.
  • Extrapolation: In The Fountains of Paradise, Arthur C. Clarke wrote about space elevators - basically long cables extending from the Earth's surface to geosynchronous orbit. These require a material with enormous tensile strength and light weight. Carbon nanotubes are strong enough in theory, so the idea is plausible; while one cannot be built today, it violates no physical principles.
  • Plot device: An example of an unsupported plot device is scrith, the material used to construct Ringworld, in the novels by Larry Niven. Scrith possesses unreasonable strength, and is unsupported by physics as it is known, but needed for the plot.
Critical analysis of materials science in science fiction falls into the same general categories. The predictive aspects are emphasized, for example, in the motto of the Georgia Tech's department of materials science and engineering – Materials scientists lead the way in turning yesterday's science fiction into tomorrow's reality. This is also the theme of many technical articles, such as Material By Design: Future Science or Science Fiction?, found in IEEE Spectrum, the flagship magazine of Institute of Electrical and Electronics Engineers.

On the other hand, there is criticism of the unrealistic materials science used in science fiction. In the professional materials science journal JOM, for example, there are articles such as The (Mostly Improbable) Materials Science and Engineering of the Star Wars Universe and Personification: The Materials Science and Engineering of Humanoid Robots.

Examples

In many cases, the materials science aspect of a fictional work was interesting enough that someone other than the author has remarked on it. Here are some of these examples, and their relationship to the real world materials science usage, if any. 

Name Source Uses Related real use
Aluminium Star Trek In the film Star Trek IV: The Voyage Home, Scotty gave instructions for the creation of the fictional material transparent aluminum. Sapphire is an aluminium oxide (Al2O3), is transparent, and used as window material in some scientific applications. In real life, scientists have announced a plastic as strong as steel, but transparent.
Beryllium Galaxy Quest, The Shadow The starship NSEA Protector is powered by large spheres of beryllium. Also, beryllium is needed for the creation of a bomb and found by investigating the metal components of a supposed "beryllium coin" in The Shadow (1994). Critics have noted this similarity. Beryllium's use in these fictional applications may arise from its actual use in some types of nuclear bombs.
Calcium carbonate Stargate SG-1 When made in suitable rocks such as calcium carbonate oxygen is produced as a by-product during the formation of Crystal tunnels by the Tokra allowing time to set up life support. There is serious thought of extracting oxygen from moon rocks for life support and propulsion. NASA has sponsored a prize (MoonROx) for the first working prototype.
Cobalt Apocalyptic fiction such as The Moon is Green, "Exhibit Piece", and On the Beach. The 5.27 year half life of radioactive 60Co is short enough to produce intense radiation, but long enough for it to disperse world-wide, and impractical to wait in shelters for it to decay. This combination of properties makes a cobalt bomb an excellent doomsday weapon. The science here is realistic. Fortunately, cobalt bombs have remained in the domain of science fiction.
Dilithium Star Trek Dilithium is fictionally used as shorthand for an extremely complex and hard crystalline structure (2(5)6 dilithium 2(:)l diallosilicate 1:9:1 heptoferranide), which occurs naturally on some planets. When placed in a high-frequency electromagnetic field, magnetic eddies are induced in its structure which keep charged particles away from the crystal lattice. This prevents it from reacting with antimatter when so energized, because the antimatter atoms never actually touch it. Therefore, it is used to contain and regulate the annihilation reaction of matter and antimatter in a starship's warp core, which otherwise would explode from the uncontrolled annihilation reaction. Though low-quality artificial crystals can be grown or replicated, they are limited in the power of the reaction they can regulate without fragmenting, and are therefore largely unsuitable for warp drive applications. Due to the need for natural dilithium crystals for interstellar travel, deposits of this material are a highly contested resource, and as such dilithium crystals have led to more interstellar conflict than all other reasons combined. In reality dilithium describes a biatomic gas.
Duralumin various The Marvel Comics character Captain America wears a suit of light weight duralumin mail beneath his costume for added protection. A duralumin briefcase was featured in the game Resident Evil: Code Veronica.
The name of the fictitious alloy duranium used in the Star Trek universe is basically a take-off of duralumin.
Duralumin is a rather old aluminum alloy with unexceptional properties by modern standards. Furthermore, other metals such as titanium are much stronger and about the same weight.
Einsteinium The Tashkent Crisis In William Craig's Cold War novel, einsteinium-119 is used to build a nuclear warhead into the casing of a Colt .45 pistol. This element possesses isotopes with very low critical masses. Values as low as 32 grams have been reported in the literature. However, an isotope of Einsteinium with an atomic weight of 119 is unrealistic - real-life mass numbers range from 245 to 257. 
Carbon, as Fullerenes and Carbon nanotubes The Fountains of Paradise, many others
In real life, fullerenes and nanotubes have rather exceptional mechanical, electrical, and thermal properties. See, for example Potential applications of carbon nanotubes.
Hard water The Flash comics Electrically charged hard water was the item that gave the first Flash (Jay Garrick) his superspeed. However, critics and even the authors realized this was unlikely, and his origin was retconned into heavy water. Heavy water, or water made with deuterium, has some high tech uses, including use a moderator in nuclear reactors. Hard water, on the other hand, is just water with lots of dissolved minerals.
Helium-3 films Moon and Iron Sky, video game Anno 2205, novels Luna: New Moon, Morning Star, Red Rising, and others. Several science fiction works have featured helium-3 extraction on the moon, including Moon, Iron Sky, Anno 2205, and Luna: New Moon. Morning Star features helium-3 mining on Phobos (a moon of Mars), while the novel Red Rising features helium-3 extraction from Mars itself. The helium-3 is valuable since it can be used to power fusion Materials on the Moon's surface contain helium-3 at concentrations on the order of between 1.4 and 15 ppb in sunlit areas, and may contain concentrations as much as 50 ppb in permanently shadowed regions. A number of people, starting with Gerald Kulcinski in 1986, have proposed to mine lunar regolith.
Hydrogen-4 The Mouse That Roared This isotope of hydrogen is referred to as Quadium and powers a thermonuclear doomsday device called the Q-bomb, which is captured by the Duchy of Grand Fenwick. Hydrogen-4 really exists, but it is very unstable with a lifetime of about 2 x 10−22 seconds. The other more stable isotopes of hydrogen, deuterium and tritium, are really used in hydrogen bombs.
Lead DC Universe Superman's X-Ray vision is unable to penetrate lead. Additionally, kryptonite radiation can be blocked by this material. Daxamites are highly susceptible to lead poisoning.
X-rays are indeed strongly attenuated, though not completely blocked, by lead. Lead poisoning is a very real effect.
Lysine Jurassic Park In the film Jurassic Park, the dinosaurs have their DNA modified so that they cannot produce lysine and must be supplied with it by the park's feeding system; otherwise they will eventually die. This is a security measure to prevent the creatures from spreading if they ever escaped into the outside world. In the book, the dinosaurs escape and survive by eating things rich in lysine such as soybeans and lentils. Real-life biological experiments use this mechanism. However, lysine is a poor choice since most modern animals (including humans) cannot synthesize it either, but thrive by including it in their diet.
Moscovium ("Element 115") urban myths, UFO conspiracy theory culture, Dark Reign, X-COM series, others In the world of UFO conspiracy theory culture during the 1980s and 1990s, Bob Lazar asserted that moscovium functioned as a gravity wave generator for UFOs, being "stepped up" (excited) to livermorium by proton bombardment, and that livermorium's decay products would include gravitons, or "a pure gravity wave" (no quantification of the gravitic field). In the X-COM series, in reference to this kind of UFO theory, "element 115" is known as elerium-115 or just elerium.
A stable isotope of "element 115" occurs in the game Dark Reign.
A stable isotope of "Element 115" powered the "Back Step" time machine system in the American television series Seven Days. An accidental environmental contamination once caused a large number of congenital disorders.
Element 115 is featured in the Call of Duty: Black Ops subseries in the "Nazi Zombies" game mode, where it is referred to as Divinium. In the game, Divinium is used for multiple purposes, such as powering weapons, teleporters, liquid drinks known as "Perk-a-Colas", special gumballs known as "Gobblegum", and even creating the zombies themselves.
In Tomb Raider III, "Element 115" is one of the four pieces of meteorite rock acquired by Lara Croft during the course of the game. The element can shoot powerful turquoise blasts, and can also be used to speed up and personally alter evolution, even evolving an already developed life form.
In the 2016 tenth season of the television show The X-Files, the episode "My Struggle" features a triangular, levitating aircraft built from alien technology. When Fox Mulder asks a scientist how the aircraft could turn invisible, the scientist states "Element 115: Ununpentium," apparently obtained from the alien spacecraft crash site at Roswell, New Mexico in 1947.
There is considerable scientific speculation about the possibility of stable elements in the Island of stability. However, moscovium has been produced by two different groups, and is highly unstable, alpha decaying in less than a second to nihonium, element 113.
Neutronium various An extremely dense material made entirely of neutrons, it is theorized to be the main constituent of neutron stars, held together by its own gravity. Authors build space ships out of it and attribute to it various desirable qualities as armor, structural material, etc. Under the immense pressure of the neutron star's gravity, the atoms at the surface form a material roughly 1013 times as dense as earth iron and at least 10 billion (1010) times as strong as earth steel and which might be incorporated into a composite material in the same way as nanotubes. Neutronium is actually expected to decompose messily at any reasonable pressure.
Perfluoropropyl furan (oxygenated perfluorocarbon for liquid breathing) The Abyss A mysterious (unnamed?) breathable liquid is used as the oxygen-carrying atmosphere in a deep-sea diving suit. A real lab rat is "drowned" in a beaker of the liquid, but overcoming initial panic, swims around quite happily. Critics have noted this as an example of an implausible science fiction effect that is really possible. Although applications for humans are limited to artificial respiration systems (e.g. LiquiVent), mice have survived prolonged submersions in liquid fluorocarbons in which the solubility of oxygen is very high. When the animal is returned to dry land, the liquid vaporizes from its lungs and it can again breathe air.
Polonium various In Sold to Satan by Mark Twain, Satan's body of radium is cloaked in a protective skin of polonium. Polonium makes a very poor protective coating – at just above room temperature, it evaporates into air in a short time.
Rhodium Jack Williamson's The Humanoids Rhodium and metals next to it in the periodic table can be used to harness "rhodomagnetism", a force similar to electromagnetism. This force has truly spectacular properties – it propagates instantaneously, can fission any heavy element, and deforms the space-time continuum, enabling faster-than-light communication and travel. Rhodomagnetism is also mentioned in passing in Fredric Brown's What Mad Universe. However, this has been derided by critics as "sheerest gobbledygook". Rhodium is a member of the platinum group of metals, which has useful but not spectacular properties.
Room temperature superconductors Ringworld and many others In science fiction, superconductors that operate at ambient temperature and pressure are used to levitate massive objects without use of power, and revolutionize many technologies, among them power transmission and energy storage. The idea is not absurd; there are serious academic conferences that examine how this might be achieved. In particular, it is very difficult to state categorically that room temperature superconductivity is impossible, since there is currently no theory to explain how high temperature superconductors (which still require cooling much below room temperature) work.
Selenium Ghostbusters, Evolution, I, Robot, Lexx In the film Ghostbusters, the site of the climactic final battle against Gozer takes place on the Ivo Shandor building which earlier in the film is stated as being “cold-riveted girders, with cores of pure selenium.” The building itself is used as an antenna to draw surrounding psychokinetic energy in order to bring Gozer into our world. The protagonists of the film Evolution use hundreds of gallons of Head & Shoulders shampoo (which they say contains selenium) to defeat the titular alien menace. Critics have noted the method of picking selenium as a poison is less than scientific.
In the book I, Robot, in the story "Runaround", selenium is used on Mercury to generate power, and to protect Gregory Powell and Michael Donovan from the heat of the Mercurian sun.
In the Lexx episode "Twilight," Stanley Tweedle becomes ill due to a selenium deficiency. He is eventually cured with a dose of dandruff shampoo.
Selenium is used with bismuth in brasses to replace more toxic lead. There is no reported use in girders. Head & Shoulders shampoo actually uses a zinc-based active ingredient, while Selsun Blue, Extra Strength Head & Shoulders, and many other brands of anti-dandruff shampoo do contain selenium sulfide.
Photo-sensitivity of selenium was discovered in the 19th century. It is really used in some types of photocells, but many alternatives are available today.
Strontium The Bionic Woman, Strontium Dog, Fallout 3 In an episode of The Bionic Woman, Jamie Summers battles a computerized complex bent on destruction. Although it does not contain a real bomb, it is to be destroyed by a military strontium bomb. The bounty hunting mutants of Strontium Dog attribute their deformities and freakish powers to strontium-90 contained in the fallout of atomic wars.
In the video game Fallout 3, one of the consumable items is called the "Nuka-Cola Quantum", which supposedly gets its unique properties from the addition of strontium-90 in its formula.
A dirty bomb containing strontium-90 is a potential terrorist weapon.
Thallium Protector and other Larry Niven works set in Known Space In these works, humans are derived from another race, in which human-like beings are the juvenile form of a smarter and tougher adult, the Pak Protector. The transformation between the forms is triggered by a virus. These beings establish an Earth colony, but the virus requires significant amounts of thallium oxide in the environment. Since the Earth does not have enough thallium, the virus dies out, and humans then evolved from the juvenile form. Critics have noted this cannot explain the similarity of DNA in humans and much older life forms on Earth. Niven's use is plausible but fictional. The same effect occurs in vitamin deficiency.
Thorium Robert A. Heinlein's novels, Star Wars, others Robert A. Heinlein envisioned thorium as being a spacecraft fuel of the near future Earth shown in Rocket Ship Galileo and Have Space Suit—Will Travel, and of the more advanced space-traveling civilization described in his novel Citizen of the Galaxy. This use is also seen in the Master of Orion series of video games. Thorium is also used as a highly explosive material in the game Star Wars: Knights of the Old Republic II.
A Soviet doomsday device in Stanley Kubrick's film Dr. Strangelove employs "Cobalt Thorium G".
In the game World of Warcraft, thorium is a workable metal mined from rock deposits that are greenish in color.
The DSiWare game "Thorium Wars" envisions a future "era of peace and prosperity" powered by thorium which is shattered when "Thorions—a super species of Thorium-based machines" turn against mankind.
Thorium can be used in nuclear reactors, and is much more abundant than uranium. This technology has been tested at a fairly large scale in reactors such as the THTR-300.
Tin foil various conspiracy theorists, Signs Supposedly, one can protect oneself against mind-control rays (government, alien, corporation, etc.) by wearing a tin-foil hat. In the movie Up, Up and Away, tin foil acts as kryptonite for the superheroes.
In current times, the material known as tin foil is made of aluminium, not tin. This matters little for the intended use since both are conductive and ductile metals.
Tin foil, or any conductive metal, can block electromagnetic waves (see Faraday cage). However, the effectiveness of the tin foil hat as electromagnetic shielding for stopping radio waves is greatly reduced by it not being a complete enclosure. Measurements of various tin foil hat designs indicate relatively little attenuation, and even enhanced response at some frequencies.
Zinc Protector (novel) and other works by Larry Niven set in Known Space Crystal zinc is the material from which fusion drive tubes are made. It is not explained what property of zinc is utilized, or why zinc is the best material for this application. There are some nuclear interactions that only happen in crystalline materials. For example, the Mössbauer effect, affecting gamma ray absorption and emission, has been observed in zinc crystals.

Carbon nanothread

From Wikipedia, the free encyclopedia
 
A carbon nanothread (informally “diamond” nanothread) is a sp3-bonded, one-dimensional carbon crystalline nanomaterial. The tetrahedral sp3-bonding of its carbon is similar to that of diamond. Nanothreads are only a few atoms across, more than 20,000 times thinner than a human hair. They consist of a stiff, strong carbon core surrounded by hydrogen atoms. Carbon nanotubes, although also one-dimensional nanomaterials, in contrast have sp2-carbon bonding as is found in graphite.

Synthesis

Nanothreads are synthesized by compressing liquid benzene to extreme pressure of 20 GPa (around 200,000 times the pressure at the surface of the Earth), and then slowly relieving that pressure. The mechanochemical synthesis reaction can be considered a form of organic solid state chemistry. The benzene chains form extremely thin, tight rings of carbon that are structurally similar to diamonds. Researchers at Cornell University have traced pathways from benzene to nanothreads, which may involve a series of organic [4+2] cycloaddition reactions along stacks of benzene molecules, followed by further reaction of unsaturated bonds. Recently synthesis of macroscopic single crystal arrays of nanothreads hundreds of microns in size has been reported. The order and lack of grain boundaries in single crystals is often very desirable because it facilitates both applications and characterization. In contrast, carbon nanotubes form only thin crystalline ropes. Control of the rate of compression and/or decompression appears to be important to the synthesis of polycrystalline and single crystal nanothreads. Slow compression/decompression may favor low energy reaction pathway(s). If the synthesis pressure for nanothreads can be reduced to 5 to 6 GPa, which is the pressure used for synthesis of industrial diamond, production on the large scale of >106 kg/yr would be possible.

The formation of nanothread crystals appears to be guided by uniaxial stress (mechanical stress in a particular single direction), to which the nanothreads consistently align. Reaction to form the crystals is not topochemical, as it involves a major rearrangement from a lower symmetry monoclinic benzene crystal to a higher symmetryhexagonal nanothread crystal. Topochemical reactions generally require commensuration between the periodicities and interatomic distances between reactant and product. The distances between benzene molecules with van der Waals separations between them must shrink by 40% or more as the short, strong covalent carbon-carbon bonds between them form during the nanothread synthesis reaction. Such large changes in geometry usual break up crystal order, but the nanothread reaction instead creates it. Even polycrystalline benzene reacts to form macroscopic single crystal packings of nanothreads hundreds of microns across. Topochemical solid state reactions such as the formation of single crystal polydiacetylenes from diacetylenes usually require a single crystal reactant to form a single crystal product.

The impetus for the formation of a hexagonal crystal appears to be the packing of circular cross section threads. The details of how it is possible to transform from a monoclinic benzene crystal to a hexagonal nanothread crystal are not yet fully understood. Further development of the theory of the effect of pressure on reactions may help.

Organic synthesis efforts towards polytwistane nanothreads have been reported.

Rotating polytwistane, a prototypical nanothread structure. Black atoms are carbon. Light grey atoms are hydrogen.
 
Polytwistane crystal viewed down its hexagonal c axis. Black atoms are carbon and pink atoms are hydrogen. The length of the threads is going into the page, showing their circular cross section and hexagonal packing that (experimentally) extends over hundreds of microns in crystals. The outline of the hexagonal unit cell is shown in blue. These crystals exfoliate into bundles of nanothreads.

History

Diamond threads were described by Arthur C. Clarke in his novel The Fountains of Paradise in 1979. Nanothreads were first investigated theoretically in 2001 by researchers at Penn State University and later by researchers at Cornell University. In 2014, researchers at Penn State University created the first sp3-carbon nanothreads in collaboration with Oak Ridge National Laboratory and the Carnegie Institution for Science. Prior to 2014, and despite a century of investigation, benzene was thought to produce only hydrogenated amorphous carbon when compressed. As of 2015, threads at least 90 nanometers in length had been created (compared to .5 meters for CNTs).

Structure

Since “diamond nanothreads” are sp3-bonded and one-dimensional they are unique in the matrix of hybridization (sp2/sp3) and dimensionality (0D/1D/2D/3D) for carbon nanomaterials.

Assuming a topological unit cell of one or two benzene rings with at least two bonds interconnecting each adjacent pair of rings, 50 topologically distinct nanothreads have been enumerated. 15 of these are within 80 meV/carbon atom of the most stable member. Some of the more commonly discussed nanothread structures are known informally as polytwistane, tube (3,0), and Polymer I. Polytwistane is chiral. Tube (3,0) can be thought of as the thinnest possible thread that can be carved out of the diamond structure, consisting of stacked cyclohexane rings. Polymer I was predicted to form from benzene at high pressure.

Although there is compelling evidence from two dimensional X-ray diffraction patterns, transmission electron diffraction, and solid-state nuclear magnetic resonance (NMR) for a structure consisting of hexagonally packed crystals of 6.5 Angstrom diameter nanothreads with largely (75 to 80%) sp3-bonding, the atomic structure of nanothreads is still under investigation. Nanothreads have also been observed by transmission electron microscopy.

Nanothreads have also been classified by their degree of saturation. Fully saturated degree 6 nanothreads have no double bonds remaining. Three bonds form between each pair of benzene molecules. Degree 4 nanothreads have a double bond remaining from benzene and thus only two bonds formed between each pair of benzene molecules. Degree 2 have two double bonds remaining. Unless otherwise specified the term nanothread is assumed to refer to a degree six structure. 

NMR has revealed that nanothread crystals consist of both degree 6 and degree 4 threads. Moreover, spin diffusion experiments show that the sections of the threads that are fully saturated degree 6 must be at least 2.5 nm long, if not longer. NMR also shows that no second hydrocarbon or carbon phase is present in nanothread crystals. Thus all of the sp2 carbon is either in degree 4 nanothreads or small amounts of aromatic linker molecules, or even smaller amounts of C=O groups. NMR provides the chemical structural information necessary to refine syntheses towards pure degree 6 nanothreads.

Carbon nitride nanothreads

Pyridine compressed slowly under pressure forms carbon nitride C5H5N nanothread crystals. They exhibit the six-fold diffraction "signature" of nanothread formation. NMR, chemical analysis and infrared spectroscopy provide further evidence for the synthesis of nanothreads from pyridine. Pyridine nanothreads incorporate significant amounts of nitrogen directly into their backbone. In contrast sp2 carbon nanotubes can only be doped with a small amount of nitrogen. A wide range of other functionalized nanothreads may be possible.

Properties

Every type of nanothread has a very high Young's modulus (stiffness). The value for the strongest type of nanothread is around 900 GPa compared to steel at 200 GPa and diamond at over 1,200 GPa. The strength carbon nanothreads may rival or exceed that of carbon nanotubes (CNTs). Molecular dynamics simulations have indicated a stiffness on the order of carbon nanotubes (approx. 850 GPa) and a specific strength of approx. 4 × 107 N·m/kg.

Much as graphite exfoliates into sheets and ultimately graphene, nanothread crystals exfoliate into fibers, consistent with their structure consisting of stiff, straight threads with a persistence length of ~100 nm that are held together with van der Waals forces. These fibers exhibit birefringence, as would be expected from their low dimensional character. In contrast, most polymers are much more flexible and often fold into crystalline lamella rather than forming into crystals that readily exfoliate.

Modeling suggests certain nanothreads may be auxetic, with a negative Poisson ratio. The thermal conductivity of nanothreads has been modeled. Modeling indicates their Bandgaps are tunable with strain over a wide range.

Potential applications

Nanothreads can be thought of essentially as "flexible diamond". The extremely high specific strength predicted for them by modeling has attracted attention for applications such as space elevators and would be useful in other applications related to transportation, aerospace, and sports equipment. They may uniquely combine extreme strength, flexibility, and resilience. Chemically substituted nanothreads may facilitate load transfer between neighbors through covalent bonding to transfer their mechanical strength to a surrounding matrix. Modeling also suggests that the kinks associated with Stone-Wales transformations in nanothreads may facilitate interfacial load transfer to a surrounding matrix, making them useful for high strength composites. In contrast to carbon nanotubes, bonds to the exterior of nanothreads need not disrupt their carbon core because only three of the four tetrahedral bonds are needed form it. The “extra” bond usually formed to hydrogen could be instead be linked to another nanothread or another molecule or atom. Nanothreads may thus be thought of as "hybrids" that are both hydrocarbon molecules and carbon nanomaterials. Bonds to carbon nanotubes require their carbon to change from near planar sp2-bonding to tetrahedral sp3-bonding, thus disrupting their tubular geometry and possibly weakening them. Nanothreads may be less susceptible to loss of strength through defects than carbon nanotubes. Thus far the extreme strength predicted for carbon nanotubes has largely not been realized in practical applications because of issues with load transfer to the surroundings and defects at various length scales from that of atoms on up.

Exfoliation into individual nanothreads may be possible, facilitating further functionalization and assembly into functional materials.

The carbon core of nanothreads is very stiff relative to the backbone of conventional polymers. They should thus be able to precisely orient molecular functions attached along their length (by substitution of hydrogen) relative to each other and to heteoatoms or unsaturated bonds in their backbone. These features may enable biological applications, for example. Defects, functional groups, and/or heteroatoms incorporated either into or exterior to the backbone of nanothreads with controlled orientation and distance between them may allow for robust, well controlled fluorescence. Doping and incorporation of heteroatoms such as nitrogen or boron into the nanothread backbone may allow for enhanced conducting or semiconducting properties of nanothreads that allow for application as photocatalysts, electron emitters, or possibly superconductors. 

Modeling suggests carbon nanothread resonators exhibit low dissipation and may be useful as chemical sensors that can detect very small mass changes.

Equality (mathematics)

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